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Sample records for cerro atajo catamarca

  1. Chatkalita, nekrasovita y otros minerales del grupo de la estannita de Veta María Eugenia, Cerro Atajo, Catamarca Chatkalita, nekrasovita y otros minerales del grupo de la estannita de veta María Eugenia, Cerro Atajo, Catamarca

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    M. F. Márquez-Zavalía

    2007-06-01

    Full Text Available En veta María Eugenia, Cerro Atajo, Catamarca, se encontró una asociación de minerales de estaño integrada por: chatkalita Cu6Fe2+Sn2S8, nekrasovita Cu26V2(Sn,As,Sb6S32, colusita Cu26V2(As,Sn,Sb6S32, kësterita Cu2(Zn,FeSnS4 y estannoidita Cu8(Fe,Zn3Sn2S12. Estos minerales, incluidos en watanabeíta, están acompañados principalmente por pirita, esfalerita, calcopirita, tetraedrita, bornita y galena; aikinita, enargita, luzonita, marcasita, arsenopirita y pirrotina participan como minerales accesorios. Chatkalita se presenta en agregados irregulares de hasta 40 µm, asociados con kësterita y estannoidita, es de color rosa-anaranjado claro, birreflectante y anisótropa, con colores de polarización pardos; su composición química (% en peso es: S=29,76-30,37, Fe=4,53-7,92, Cu=39,13-43,21, Zn=0,75-5,53, As=0,19- 2,42, Sn=15,27-20,50 y Sb=0,00-0,32. Nekrasovita es isótropa, de color pardo con leve tinte rosa-violáceo y está asociada con estannoidita; su composición química es: S=30,29-30,63, Fe=3,41-4,75, Cu=44,26-45,70, Zn=0,56-1,00, As=4,18-4,71, Sn=12,53-13,64 y Sb=0,71- 0,77. Colusita es pardo amarillenta, isótropa, se presenta como parches irregulares y cintas discontinuas en tennantita; su composición química es: S=30,59-30,74, Fe=2,18-3,58, Cu=47,22-48,13, Zn=0,21-0,64, As=6,38-6,61, Sn=9,04-9,33 y Sb=0,49-1,66. Kësterita es pardo grisácea, con débil birreflectancia y anisotropía y colores de polarización pardos, a menudo se presenta bordeada por chatkalita; su composición química es: S=28,68-29,14, Fe=1,98-2,14, Cu=31,06-32,51, Zn=9,03-11,57 y Sn=26,39-27,03. Estannoidita es de color castaño, pleocroica (castaño-rosado a pardo-grisáceo y anisótropa con colores de polarización pardos y pardo-amarillentos, ocurre en parches irregulares y como bandas bordeando tennantita; su composición química es: S=29,11-29,83, Fe=8,45-10,30, Cu=38,05-41,01, Zn=3,18-4,90, y Sn=15,84-18,94. La reflectividad y dureza de pulido de

  2. Chatkalita, nekrasovita y otros minerales del grupo de la estannita de Veta María Eugenia, Cerro Atajo, Catamarca

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    M. F. Márquez-Zavalía

    2007-06-01

    Full Text Available En veta María Eugenia, Cerro Atajo, Catamarca, se encontró una asociación de minerales de estaño integrada por: chatkalita Cu6Fe2+Sn2S8, nekrasovita Cu26V2(Sn,As,Sb6S32, colusita Cu26V2(As,Sn,Sb6S32, kësterita Cu2(Zn,FeSnS4 y estannoidita Cu8(Fe,Zn3Sn2S12. Estos minerales, incluidos en watanabeíta, están acompañados principalmente por pirita, esfalerita, calcopirita, tetraedrita, bornita y galena; aikinita, enargita, luzonita, marcasita, arsenopirita y pirrotina participan como minerales accesorios. Chatkalita se presenta en agregados irregulares de hasta 40 µm, asociados con kësterita y estannoidita, es de color rosa-anaranjado claro, birreflectante y anisótropa, con colores de polarización pardos; su composición química (% en peso es: S=29,76-30,37, Fe=4,53-7,92, Cu=39,13-43,21, Zn=0,75-5,53, As=0,19- 2,42, Sn=15,27-20,50 y Sb=0,00-0,32. Nekrasovita es isótropa, de color pardo con leve tinte rosa-violáceo y está asociada con estannoidita; su composición química es: S=30,29-30,63, Fe=3,41-4,75, Cu=44,26-45,70, Zn=0,56-1,00, As=4,18-4,71, Sn=12,53-13,64 y Sb=0,71- 0,77. Colusita es pardo amarillenta, isótropa, se presenta como parches irregulares y cintas discontinuas en tennantita; su composición química es: S=30,59-30,74, Fe=2,18-3,58, Cu=47,22-48,13, Zn=0,21-0,64, As=6,38-6,61, Sn=9,04-9,33 y Sb=0,49-1,66. Kësterita es pardo grisácea, con débil birreflectancia y anisotropía y colores de polarización pardos, a menudo se presenta bordeada por chatkalita; su composición química es: S=28,68-29,14, Fe=1,98-2,14, Cu=31,06-32,51, Zn=9,03-11,57 y Sn=26,39-27,03. Estannoidita es de color castaño, pleocroica (castaño-rosado a pardo-grisáceo y anisótropa con colores de polarización pardos y pardo-amarillentos, ocurre en parches irregulares y como bandas bordeando tennantita; su composición química es: S=29,11-29,83, Fe=8,45-10,30, Cu=38,05-41,01, Zn=3,18-4,90, y Sn=15,84-18,94. La reflectividad y dureza de pulido de

  3. Los granitos peraluminosos de las Sierras de Vinquis, Cerro Negro y Zapata (Sierras Pampeanas, provincia de Catamarca, Argentina

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    Medina, M. E.

    1992-12-01

    Full Text Available The studied plutons are close to several batholiths of this region, as Sierra de Mazán and other, but with some mineralogical peculiarities. The magmatic cordierite, common in proximate places, is scarce, as sillimanite, while the andalusite is very rare, with few tourmaline. Fluorite and allanite are also typical accasories only in the granites of the Sierra de Zapata. All plutons are peraluminous of potassic tendency, with cortical affinity.The interpretation of the geochemical values distinguishes between granites of different maturity, emplaced under a predominant influence of active margin for Cerro Negro and Vinquis, while the batholith of Zapata has, below these concepts, a marked feature of within plate.The mineralogical associations suggest that the granites of Cerro Negro and Vinquis were emplaced to pressures of 2 kb or less and temperature of 650º C, while the granites of Zapata had done under conditions of lesser pressure, between 1.5 and 2.0 kb and lower temperature, 600-650º C.A grandes rasgos, los plutones estudiados tienen semejanzas con otros del entorno regional, tal como los de la Sierra de Mazán, pero con peculiaridades mineralógicas. La cordierita magmática, que en lugares próximos es muy abundante, es aquí escasa, al igual que la sillimanita, mientras que la andalucita es muy rara y la turmalina poco frecuente. La fluorita y allanita son accesorios comunes y de cierta abundancia sólo en los granitos de la Sierra de Zapata.Todos los plutones son peralumínicos y de tendencia potásica, con neta afinidad cortical. El estudio estadístico de datos geoquímicos seleccionados, permite diferenciar agrupaciones que tienen un reflejo satisfactorio en los plutones caracterizados, por encima de las variaciones de facies. La interpretación de los valores geoquímicos distingue granitos de desigual madurez, emplazados bajo una influencia predominante de margen activo o intraplaca de características continentales, en

  4. Análisis paleoambiental y procedencia de los depósitos en el extremo suroeste de la sierra de Aconquija, provincia de Catamarca

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    Claudia Inés Galli

    2012-12-01

    Full Text Available Se realizó el estudio de facies y petrografía de los depósitos sedimentarios y volcaniclásticos-sedimentarios expuestos en la zona de cerro Atajo, cerro Blanco y alrededores del río Capillita, provincia de Catamarca, con el fin de analizar los paleoambientes sedimentarios y la proveniencia de los mismos. Estos comprenden bancos rojos depositados por sistemas fluviales correspondientes a la Formación Hualfin (Eoceno-Mioceno inferior? y acumulaciones clásticas, volcaniclásticas y depósitos volcánicos primarios intercalados, del Complejo Volcánico Farallón Negro (Mioceno superior- Plioceno. La asociación de facies de la Formación Hualfin está caracterizada por el desarrollo de una sucesión de formas de lecho predominantemente arenosas, en menor medida, barras gravosas conformando un sistema fluvial entrelazado arenoso poco profundo perenne. Las muestras analizadas de la Formación Hualfin corresponden a arenitas cuarzosas, derivadas principalmente del resultado de la erosión de rocas graníticas y gnéisicas con elevados porcentajes de cuarzo, que muestran proveniencias de interior cratónico y orógeno reciclado cuarzoso. El paleoambiente de los depósitos del Complejo Volcánico Farallón Negro evoluciona desde un sistema fluvial de río entrelazado distal areno dominado a uno de sistema fluvial entrelazado gravoso asociado a flujos de gravedad, para culminar en un sistema fluvial entrelazado gravoso somero. En estos depósitos se han podido diferenciar de base a techo: wackes cuarzosas, con proveniencias de orógeno reciclado que habría derivado del basamento; wackes líticas, con alto porcentaje de fragmentos líticos volcánicos de basaltos y con proveniencia de arco no disectado. Wackes feldespáticas, con altos porcentajes de plagioclasa y en menor medida clastos de andesitas, producto del cambio composicional del aporte volcánico.

  5. Nuevas citas de Asteraceae para la provincia de Catamarca (Argentina) New records of Asteraceae for the province of Catamarca (Argentina)

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    Susana E. Freire; Bayón, Néstor D.; Daniel A. Giuliano; Luis Ariza Espinar; Sáenz, Alcides A.; Claudia Monti; Gustavo Delucchi

    2011-01-01

    Se mencionan los siguientes nuevos registros de Asteráceas para la provincia de Catamarca, Argentina: Baccharis acaulis, B. boliviensis var. latifolia, B. flexuosa, B. glutinosa var. angustissima, B. stenophylla (Tribu Astereae), Eupatorium patens var. tomentosum (Tribu Eupatorieae), Cosmos bipinnatus, C. peucedanifolius var. peucedanifolius, Helianthus annuus (Tribu Heliantheae), Gamochaeta erythractis, G. longipedicellata, Gnaphalium lacteum, Tessaria integrifolia var. integrifolia (Tribu I...

  6. Evolución tectónica andina entre las Sierras de Hualfín, capillitas y extremo sur de Aconquija, provincia de Catamarca

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    Raúl Seggiaro

    2014-12-01

    Full Text Available Las Sierras Pampeanas septentrionales están integradas por bloques de basamento cristalino basculados por fallas de rumbo NE-SO, que forman parte del lineamiento de Aconquija o de Tucumán. Las unidades cenozoicas, dispuestas en los valles intramontanos que separan las sierras de Capillitas, Hualfín y Aconquija, presentan relaciones de inconformidad sobre el basamento y registran cuatro sucesivos eventos deformacionales andinos. El primer evento deformacional presenta estratos de sincrecimiento asociados a fallas normales en la Formación Hualfín. Durante el segundo evento, la Formación Hualfín fue intensamente plegada y erosionada previamente a la depositación del Complejo Volcánico Farallón Negro. El tercer evento, de carácter transtensivo, se registra en el Compelo Volcánico Farallón Negro con fallas normales y discordancias progresivas. Este evento es coincidente con la irrupción del vulcanismo en la cuenca. A los fines de analizar la cinemática de la cuarta y última etapa de deformación se realizaron mediciones de indicadores cinemáticos a lo largo de fallas regionales y estructuras menores, con resultados que reflejan desplazamientos dextrales transpresivos. Los desplazamientos correspondientes a esta etapa estarían asociados a la elevación de las sierras y el emplazamiento de cuerpos subvolcánicos, algunos de los cuales como los de cerro Atajo, Capillitas y Agua Rica entre otros, son de interés económico. La tectónica transpresiva, aún vigente, se registra en fallas activas asociadas a avalanchas y flujos de detritos provenientes de las laderas de las sierras.

  7. Seismological studies at Cerro Prieto

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    Majer, E.L.; McEvilly, T.V.; Albores, A.; Diaz, S.C.

    1980-01-01

    A radio-telemetered 12-station seismographic network was operated in a dense-array configuration over the Cerro Prieto field as shown in Fig. 1. Horizontal and vertical 4.5-Hz geophones were deployed with interstation distances of order 1 km in a multi-purpose survey for microearthquake occurrence and possible anomalies in P- and S-wave velocities and attenuation associated with the field. Although data obtained thus far are limited, attenuation and velocity studies at Cerro Prieto show anomalies related to the production area. This suggests that these data might be useful for delineating the field boundaries. 16 refs.

  8. Overview of Cerro Prieto studies

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    Lippmann, M.J.

    1983-01-01

    The studies performed on the Cerro Prieto geothermal field, Mexico, since the late 1950's are summarized. Emphasis is given to those activities leading to the identification of the sources of heat and mass, the fluid flow paths, and the phenomena occurring in the field in its natural state and under exploitation.

  9. Catálogo de hongos gasteroides (Basidiomycota de Catamarca, Argentina Catalogue of gasteroid fungi (Basidiomycota from Catamarca, Argentina

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    María Marta Dios

    2011-06-01

    Full Text Available Se realiza un listado de los hongos gasteroides de la provincia de Catamarca (Argentina basado en la bibliografía hasta abril de 2010. En total aparecen citadas 43 especies distribuidas en 2 órdenes, 4 familias y 13 géneros. El número de especies catalogadas es relativamente baja pero este número probablemente se incremente cuando se estudien las zonas aún no muestreadas como son las regiones fitogeográfícas de la Puna y las Yungas.A compiled check list of gasteroid fungi of Catamarca Province (Argentina was made. It was based on literature records, available until April 2010. There were 43 species of fungi distributed in 2 orders, 4 families and 13 genera. The number of species recorded in this area was relatively poor but it is likely to increase with the study of unexplored areas not yet surveyed as the phytogeographical regions of the Puna and Yungas.

  10. Nuevas citas de Asteraceae para la provincia de Catamarca (Argentina New records of Asteraceae for the province of Catamarca (Argentina

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    Susana E. Freire

    2011-06-01

    Full Text Available Se mencionan los siguientes nuevos registros de Asteráceas para la provincia de Catamarca, Argentina: Baccharis acaulis, B. boliviensis var. latifolia, B. flexuosa, B. glutinosa var. angustissima, B. stenophylla (Tribu Astereae, Eupatorium patens var. tomentosum (Tribu Eupatorieae, Cosmos bipinnatus, C. peucedanifolius var. peucedanifolius, Helianthus annuus (Tribu Heliantheae, Gamochaeta erythractis, G. longipedicellata, Gnaphalium lacteum, Tessaria integrifolia var. integrifolia (Tribu Inuleae, Chuquiraga ruscifolia (Tribu Mutisieae, Senecio crepidifolius, S. subulatus var. subulatus, Xenophyllum incisum var. incisum (Tribu Senecioneae. Se citan además el hábitat de los taxones y las provincias fitogeográficas que integran. Se propone una nueva combinación, Baccharis glutinosa Pers. var. angustissima (DC. Giuliano.The following Asteraceae are mentioned for the province of Catamarca: Baccharis acaulis, B. boliviensis var. latifolia, B. flexuosa, B. glutinosa var. angustissima, B. stenophylla (Tribe Astereae, Eupatorium patens var. tomentosum (Tribe Eupatorieae, Cosmos bipinnatus, C. peucedanifolius var. peucedanifolius, Helianthus annuus (Tribe Heliantheae, Gamochaeta erythractis, G. longipedicellata, Gnaphalium lacteum, Tessaria integrifolia var. integrifolia (Tribe Inuleae, Chuquiraga ruscifolia (Tribe Mutisieae, Senecio crepidifolius, S. subulatus var. subulatus, Xenophyllum incisum var. incisum (Tribe Senecioneae. The habitat and phytogeographic provinces of the taxa are mentioned. The following new combination is proposed: Baccharis glutinosa Pers. var. angustissima (DC. Giuliano.

  11. Geothermal drilling in Cerro Prieto

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    Dominguez A., Bernardo

    1982-08-10

    The number of characteristics of the different wells that have been drilled in the Cerro Prieto geothermal field to date enable one to summarize the basic factors in the applied technology, draw some conclusions, improve systems and procedures, and define some problems that have not yet been satisfactorily solved, although the existing solution is the best now available. For all practical purposes, the 100 wells drilled in the three areas or blocks into which the Cerro Prieto field has been divided have been completed. Both exploratory and production wells have been drilled; problems of partial or total lack of control have made it necessary to abandon some of these wells, since they were unsafe to keep in production or even to be used for observation and/or study. The wells and their type, the type of constructed wells and the accumulative meters that have been drilled for such wells are summarized.

  12. The Structure at Sierra Ambato, Catamarca, Argentina: A New Meteorite Impact Site?

    Science.gov (United States)

    Acevedo, R. D.; Rocca, M.; Alonso, R.; Rabassa, J.; Ponce, J. F.

    2012-09-01

    A new possible impact crater was discovered in Catamarca Province: the structure at Sierra Ambato (28º 03" 23.22” S, 66º 03" 11.06” W), located at Sierras Pampeanas (3,500 m.a.s.l). It has 1.0 km in diameter.

  13. El yacimiento de estaño Vil Achay, Catamarca

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    Ana S. Fogliata

    2004-03-01

    Full Text Available El yacimiento de estaño Vil Achay está ubicado en el flanco suroriental de la sierra de Fiambalá, provincia de Catamarca. Las rocas más antiguas aflorantes son anfibolitas pertenecientes al Gabro Fiambalá de edad ordovícica. Están intruidas por el granito El Salto de posible edad carbonífera. En las cercanías del contacto entre ambas unidades aflora un dique granítico emplazado en las anfibolitas, portador de la mineralización. La alteración hidrotermal en el dique granítico corresponde a albitización y greisenización. La mineralización (casiterita se encuentra diseminada en el dique. Existen sectores con mayor concentración de casiterita controlados por fracturas subverticales cerca del contacto oeste del dique. Se identificó la siguiente secuencia mineral: casiterita, magnetita, wolframita (escasa, calcopirita, pirita, covelina, calcosina, hematita, limonita, malaquita y azurita. El granito El Salto es meta a peraluminoso, postectónico, enriquecido en Rb, Nb, Y y Sn. La distribución de las tierras raras muestran fuerte fraccionamiento en tierras raras pesadas y relativo en tierras raras livianas. Tal fraccionamiento es indicativo de la actividad de los aniones de F en los fluidos mineralizantes. La gran actividad del F en los fluidos es responsable de la mineralización de Sn en greisen. Se propone que el depósito forma parte de un sistema tipo greisen abierto rico en F durante el estadio tardío magmático hidrotermal genéticamente relacionado con el granito El Salto.

  14. El yacimiento de estaño Vil Achay, Catamarca The Vil Achay tin deposit of Catamarca, Argentina.

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    Ana S. Fogliata

    2004-03-01

    Full Text Available El yacimiento de estaño Vil Achay está ubicado en el flanco suroriental de la sierra de Fiambalá, provincia de Catamarca. Las rocas más antiguas aflorantes son anfibolitas pertenecientes al Gabro Fiambalá de edad ordovícica. Están intruidas por el granito El Salto de posible edad carbonífera. En las cercanías del contacto entre ambas unidades aflora un dique granítico emplazado en las anfibolitas, portador de la mineralización. La alteración hidrotermal en el dique granítico corresponde a albitización y greisenización. La mineralización (casiterita se encuentra diseminada en el dique. Existen sectores con mayor concentración de casiterita controlados por fracturas subverticales cerca del contacto oeste del dique. Se identificó la siguiente secuencia mineral: casiterita, magnetita, wolframita (escasa, calcopirita, pirita, covelina, calcosina, hematita, limonita, malaquita y azurita. El granito El Salto es meta a peraluminoso, postectónico, enriquecido en Rb, Nb, Y y Sn. La distribución de las tierras raras muestran fuerte fraccionamiento en tierras raras pesadas y relativo en tierras raras livianas. Tal fraccionamiento es indicativo de la actividad de los aniones de F en los fluidos mineralizantes. La gran actividad del F en los fluidos es responsable de la mineralización de Sn en greisen. Se propone que el depósito forma parte de un sistema tipo greisen abierto rico en F durante el estadio tardío magmático hidrotermal genéticamente relacionado con el granito El Salto.The Vil Achay tin deposit is located on the south-eastern flank of Sierra de Fiambalá in the province of Catamarca. The oldest exposed rocks are amphibolites of the Fiambalá Gabbro (Ordovician, intruded by the El Salto Granite of possible Carboniferous age. Within the amphibolites, near the contact between the two units, is a mineralized granitic dyke, exhibiting hydrothermal alteration (albitization and greisenization. Cassiterite is disseminated in the

  15. Geohydrology of the Cerro Prieto geothermal aquifer

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    Sanchez R, J.; de la Pena L, A.

    1981-01-01

    The most recent information on the Cerro Prieto geothermal aquifer is summarized, with special emphasis on the initial production zone where the wells completed in the Alpha aquifer are located. These wells produce steam for power plant units 1 and 2. Brief comments also are made on the Beta aquifer, which underlies the Alpha aquifer in the Cerro Prieto I area and which extends to the east to what is known as the Cerro Prieto II and Cerro Prieto III areas. The location of the area studied is shown. The Alpha and Beta aquifers differ in their mineralogy and cementing mineral composition, temperatures, and piezometric levels. The difference in piezometric levels indicates that there is no local communication between the two aquifers. This situation has been verified by a well interference test, using well E-1 as a producer in the Beta aquifer and well M-46 as the observation well in the Alpha aquifer. No interference between them was observed. Information on the geology, geohydrology, and geochemistry of Cerro Prieto is presented.

  16. Recent activities at the Cerro Prieto field

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    Alonso, E. H.; Dominguez, A.B.; Lippmann, M.J.; Manon, M.A.; Schroeder, R.C.; Witherspoon, P.A.

    1978-01-01

    The purpose of this paper is to describe some of the latest activities of interest to reservoir engineers at the Cerro Prieto geothermal field. Special emphasis is given to the wells drilled in 1978 for exploration purposes and to provide steam to the existing and future power plants. The present power output is 75MW. Two additional 37.5MW units are scheduled to go on line in March and May 1979, while the total generating capacity at Cerro Prieto will reach about 400MW in 1985. Additional information is available in a number of papers in References 1 and 2.

  17. Material progress at Cerro Prieto, Mexico

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    Mercado, A.M.

    1978-01-01

    A brief general description is presented about the principal problems observed on the materials used in the Cerro Prieto geothermal project. These include those problems that have been observed in drill pipes, well casing separation equipment and conduction pipes for geothermal water and steam as well as the problems observed in geothermal power plant materials.

  18. Exploration and development of Cerro Prieto

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    Teilman, M.A.; Cordon, U.J.

    1981-01-01

    A brief retrospective of the exploration and field model development at Cerro Prieto are presented. Representative field models are presented for each of the work phases. These models demonstrate how the concept of the field evolved - from a small 2 km/sup 2/ area with a relatively unknown reservoir configuration - to a geothermal resource area over 20 km/sup 2/ where the hydrothermal processes and structural environment are being studied in detail. A model integrating information from these studies was developed.

  19. Caracterización de manantiales del departamento Ancasti en la provincia de Catamarca (Argentina)

    OpenAIRE

    Denim, Pablo; l Instituto Nacional de Tecnología, Estación Experimental Agropecuaria Catamarca, Ruta 33- Km 4,5. Valle Viejo, Catamarca, Argentina.; Cano, Laura; Instituto Nacional de Tecnología, Estación Experimental Agropecuaria Catamarca, Ruta 33- Km 4,5. Valle Viejo, Catamarca, Argentina.; Castro, Ornella; l Instituto Nacional de Tecnología, Estación Experimental Agropecuaria Catamarca, Ruta 33- Km 4,5. Valle Viejo, Catamarca, Argentina.

    2015-01-01

    Las poblaciones de la provincia de Catamarca, Argentina no tienen acceso al agua o el acceso es muy precario. Entre estas poblaciones se encuentran las de El Huayco, El Arbolito y El Puesto Nuevo, en el departamento Ancasti, donde cada familia y una escuela de la zona poseen su propia vertiente. En estos lugares se realizaron obras de captación de agua, a fin de que cada familia y la escuela tengan disponibilidad de este recurso. Con el objetivo de conocer la calidad del agua de abastecimient...

  20. Prospecciones arqueológicas en Andalgalá (Catamarca: resultados y perspectivas Archaeological Surveys In Andalgalá, Catamarca: Results And Prospects

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    Inés Gordillo

    2010-12-01

    Full Text Available En el presente trabajo damos a conocer los resultados de las investigaciones realizadas en la región de Andalgalá (Catamarca, Argentina. Tras una discusión de los antecedentes en el área y un planteo de los lineamientos metodológicos empleados, presentamos el análisis del material cerámico y arquitectónico recuperado y relevado durante las prospecciones, incorporando información de colecciones arqueológicas. Los resultados sugieren procesos complejos para el área, donde confluyen estilos cerámicos adscriptos a diversas regiones y períodos. La muestra analizada no permitió detectar una circunscripción espacial de las ocupaciones, ya que en los sectores recorridos el material cerámico es temporalmente diagnóstico del Formativo en adelante. Asimismo, observamos ciertas tendencias que pueden servir como hipótesis para trabajos futuros. Sobre la base de la evidencia analizada proponemos una historia ocupacional tentativa y remarcamos el intenso dinamismo que la domina.In this paper we present the results of investigations conducted in the Andalgalá Region, Catamarca, Argentina. After a discussion of previous research in the area and an outline of the methodology employed, we present the results of ceramics analysis, architectural evidence retrieved and recorded during systematic surveys, and data from archaeological collections. The results suggest a complex occupational history of the area, where ceramic styles from different periods and regions converge. The sample did not allow us to identify the spatial limits of the different occupations, as in all areas surveyed the ceramic material is temporally diagnostic from the Formative period on. Nevertheless, we detected some tendencies that may serve as hypotheses for future research. On the basis of the evidence analyzed, we propose a tentative occupational history and note the intense dynamism that dominated the area.

  1. Incidence of social resistance in provincial mining legislation. The cases of Córdoba and Catamarca (2003-2008

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    Lucas Christel

    2013-11-01

    Full Text Available During the last decade in Argentina, the growth of open pit mining has faced strong social resistance and provincial laws prohibiting such activity. This work aims to analyse the ways in which the different subnational political regimes and economic systems impact upon the possibility of incidence of social resistance on provincial mining legislation, looking at the cases of Cordoba and Catamarca.

  2. Apellidos, familias y linajes moleculares: el caso de Azampay, Catamarca Sobrenomes, famílias e linhagens moleculares: o caso de Azampay, Catamarca Surnames, Families and Molecular Lineages: the Case of Azampay, Catamarca

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    Virginia Ramallo

    2011-12-01

    Full Text Available En todas las sociedades se encuentran múltiples maneras de clasificar la ascendencia y descendencia de cada persona. Además de los vínculos establecidos desde el nacimiento y de los adquiridos, las relaciones de parentesco tienen un correlato biológico que permite definir linajes. Se emplearon técnicas de análisis molecular para caracterizar el perfil genético de la comunidad de Azampay, Catamarca. Los objetivos fueron establecer porcentajes y aportes diferenciales de componentes americanos y extra-americanos en esta población con mezcla génica, reconstruir su historia migratoria y cotejar los linajes moleculares con genealogías basadas en registros oficiales y relatos orales. Entre los haplogrupos masculinos, 88 % tuvieron procedencia foránea, mientras que 100% de los antepasados femeninos fueron amerindios. La migración laboral es una estrategia económica establecida, estando la crianza de nietos a cargo de sus abuelos. Es la vía de introducción de nuevos linajes moleculares, sin registrar siempre un correlato en la cantidad de apellidos.Em todas as sociedades humanas encontran-se diversas maneiras de classificar a ascendência e descendência de cada pessoa. Além das ligações estabelecidas no nascimento e das adquiridas ao longo da vida, as relações familiares têm um correlato biológico que permite definir linhagens. Nosso trabalho apresenta resultados obtidos por meio de técnicas de análise molecular visando caracterizar o perfil genético da atual comunidade de Azampay, Catamarca. Os objetivos principais foram determinar os diferentes componentes e aportes das linhagens americanss e extra-americanos nesta população mestiça, reconstruir a história migratória y comparar essas linhagens moleculares com as genealogias basadas em registros oficiais e histórias orais. Entre os haplogrupos masculinos, 88% tiveram origem forânea, enquanto que 100% dos antepassados femininos foram ameríndios A migração laboral

  3. Geologic model of the Cerro Prieto geothermal field

    Science.gov (United States)

    Halfman, S. E.; Howard, J. H.; Vonderhaar, S. P.

    1982-09-01

    One of the tasks under the Mexican-American cooperative agreement is the comprehensive geologic study of the Cerro Prieto geothermal field. Using logs from over seventy deep wells as the basic source of information on the subsurface geology, a working model of the Cerro Prieto geothermal field is developed.

  4. TECNOLOGÍA DE CAZA EN LA QUEBRADA DE ANTOFALLA, DEPARTAMENTO ANTOFAGASTA DE LA SIERRA, CATAMARCA / Hunting technology in the Antofalla Valley, Antofagasta de la Sierra Department, Catamarca.

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    Enrique Alejandro Moreno

    2011-12-01

    Full Text Available Las prácticas de cacería de camélidos silvestres han sido relevantes para la reproducción de las poblaciones humanas en los Andes Centro-Sur durante los últimos 12000 años aproximadamente. Para la materialización de esta práctica, son relevantes las armas utilizadas para poder dar muerte a las presas pretendidas. Una alternativa para interpretar el tipo de arma es a través de la información obtenida del análisis de las puntas de proyectil líticas registradas mediantes metodologías disciplinarias. Como caso de estudio utilizamos los datos obtenidos de la prospección intensiva y sistemática desarrollada en la quebrada de Antofalla, ubicada en el Departamento Antofagasta de la Sierra, Provincia de Catamarca, Argentina. Para evaluar las características de esta tecnología nos centraremos en tres grandes aspectos: las características tecno-morfológicas de estos instrumentos, la asignación a distintos tipos de armas y sus posibles asignaciones cronológicas, los espacios donde fueron registrados estos especímenes, en relación con las características de los paisajes cinegéticos.   Palabras clave: Tecnología; cacería; camélidos; armas; paisaje.   Abstract The hunting practice of wild camelids has been relevant for the reproduction of human populations in the South Central Andes for the last 12000 years. An important aspect for the materialization of this practice, are the weapons used in order to kill the alleged preys. In this paper we shall introduce the different weapons used by human populations, mainly, through the information obtained from the analysis of of lithic projectile points. As a case study we will retake the information obtained from the intensive and systematic prospection developed at the Antofalla ravine, located in the Departamento Antofagasta de la Sierra, Provincia de Catamarca. In order to evaluate the features of this technology, we will focus on three aspects: the techno-morphological characteristics

  5. ZOOARQUEOLOGÍA DE LA ALDEA FORMATIVA DE PALO BLANCO (TINOGASTA, CATAMARCA, ARGENTINA / Zooarchaeology of the formative village of Palo Blanco (Tinogasta, Catamarca, Argentina

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    Juan Pablo Miyano

    2015-12-01

    Full Text Available En el presente trabajo se abordan los conjuntos arqueofaunísticos de la localidad arqueológica de Palo Blanco recuperados en intervenciones realizadas en la década de 1960 y en la década de 2000. Esta localidad se encuentra emplazada en el sector norte del bolsón de Fiambalá (Tinogasta, Catamarca y se compone de varios núcleos habitacionales de distribución dispersa, predominantemente rectangulares y con muros de tapia. Su ocupación no fue sincrónica y se extiende desde el siglo III al siglo X A.D. La tendencia en el aprovechamiento de recursos faunísticos identificada fundamentalmente a partir del abordaje de los conjuntos de dos núcleos habitacionales sugiere que los camélidos fueron el principal recurso de origen animal utilizado en la aldea, en donde se encontraron especies tanto domesticadas (Lama glama como silvestres (Vicugna vicugna. Además, la presencia predominante de camélidos subadultos sugiere una estrategia de pastoreo vinculada al aprovechamiento de recursos primarios como carne, médula y grasa. Los resultados a los que se arribaron permiten profundizar en el conocimiento de las actividades económicas de los grupos humanos que habitaron la aldea de Palo Blanco a lo largo del primer milenio de la era. AbstractIn this paper we approach the archaeofaunistic remains recovered during excavations of the archeological locality of Palo Blanco in the decades of 1960 and 2000. Palo Blanco is located in the north sector of the Bolsón of Fimabalá area (Tinogasta, Catamarca and it is composed of several rectangular shaped dwellings with tapia-style walls and dispersed distribution. The period of occupation of the village was between the third and tenth century A.D. although the dwellings were not inhabited synchronously. The identified tendency in the exploitation of faunal resources indicates that the camelids were the main resources. Osteometric studies show that domestic and wild camelids (Lama glama and Vicugna vicugna

  6. Cacao 3 (Cc 3, Arte rupestre del formativo temprano en Antofagasta de la Sierra, Catamarca, Argentina

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    Alvaro Rodrigo Martel

    2004-01-01

    Full Text Available En el presente trabajo hemos abordado el estudio de la producción del arte rupestre del sitio Cacao 3 –Cc3- (Antofagasta de la Sierra, Catamarca con relación a las prácticas socioculturales de grupos agropastoriles del periodo Formativo Temprano en la Puna meridional argentina, haciendo hincapié en el emplazamiento del sitio y su asociación contextual con las demás evidencias arqueológicas conocidas para el área de estudio y estableciendo las relaciones entre las manifestaciones rupestres de Cc3 con las de otros sitios, a nivel micro y macrorregional, a través de indicadores estilísticos

  7. Arqueología virtual aplicada al sitio Villavil, Catamarca, Argentina

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    Julieta Lynch

    2014-10-01

    Full Text Available En este trabajo se presenta los resultados de los trabajos de relevamiento realizados en el sitio arqueológico Villavil. El mismo se encuentra en la región norte del valle de Hualfín, Catamarca, Argentina. Esta región estuvo habitada por poblaciones humanas desde tiempos tempranos hasta la llegada incaica y la posterior conquista española. A partir del registro del sitio con estación total se aplicaron programas de realidad virtual con el fin de proporcionar un conjunto más completo de datos al momento de la interpretación de la funcionalidad intrasitio, para momentos previos y posteriores a la llegada incaica en esta región del Noroeste Argentino.

  8. Catamarca: Peripheral periphery. Locus of en unciation and peripheral context construction

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    Silvia Carina Valiente

    2012-01-01

    Full Text Available This paper seeks to question the construction of the Argentine north-west, of Catamarca and particularly of Santa María, through time, as peripheral areas from the hegemonic viewpoint. We will problematize, from the standpoint of the coloniality of power, the way time periods are fragmented from a locus of enunciation which could be defined as Colonialist-Capitalist-Neoliberal, which has become hegemonic since the conquest of America. First it was the Colonial period, later on it was the development of Capitalism, and as of late it is within Neoliberalism that this locus has enabled an expropriation dynamics, in the present times, which is linked with the mega-mining that, during the past two decades, has stressed the region's peripheral status. This dynamics, understood as the continuation of a pattern of colonial power, has operated shaping territories, subjectivities and nature, to which we will also add the way time is fragmented

  9. Composición corporal en escolares de la provincia de Catamarca, Argentina

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    Lomaglio, Delia Beatriz

    2005-01-01

    Full Text Available Por primera vez se estimó la composición corporal de niños en edad escolar de la provincia de Catamarca, utilizando las ecuaciones propuestas por Gurney y Jellife (1973, Siri (1961 y Slaughter et al (1988 fundamentadas en la estima de la densidad corporal y los pliegues adiposos subcutáneos. También se calcularon otros parámetros nutricionales como el IMC y diversas relaciones que reflejan la distribución del perfil de grasa. La muestra fue de 5497 niños y niñas entre 5 y 15 años de edad, de siete departamentos provinciales. Las mediciones fueron realizadas entre 1980 y 2000, lo que facilitó, además, un análisis secular de la variabilidad de los parámetros estudiados. Los resultados obtenidos se han contrastado con los correspondientes a otros grupos humanos previamente estudiados con idéntica metodología. Por lo que respecta en concreto al sobrepeso y obesidad calculado a partir de los criterios de Cole et al (2000 cabe mencionar que la prevalencia de ambas condiciones malnutritivas es considerablemente inferior a la registrada hasta el momento para la mayoría de los países latinoamericanos utilizando protocolos basados en el IMC. Concretamente la proporción actual es en Catamarca de un 7% de sobrepeso y un 2% de obesidad, habiéndose observado que la tendencia secular al aumento de ambas condiciones, ha sido muy leve en los últimos veinte años.

  10. Pobreza y trasnformaciones económicas en Catamarca y Tucumán (1980-2002

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    Osatinsky, Ariel

    2009-01-01

    Full Text Available In the beginning of the 21st century Catamarca and Tucumán were showing important differences in social and economic level. While the first, with a more reduced and tradicional productive structure, had the less percentage of poor homes in the whole “Norte Grande Argentino”, Tucumán suffered major levels of poverty, being its economy the most developed of the north of the country. Having in mind that the poverty is intimately related to the economy, the present article is trying to analyze the characteristics of the poverty in Tucumán and Catamarca in 2001, and to investigate about the relations which existed between the differential levels of privation in both provinces and the transformations which suffered their respective productive structures in the last decades of the 20th century.

  11. Los marsupiales (Mammalia del Mioceno Superior de la Formación Cerro Azul (Provincia de La Pampa, Argentina

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    Visconti, G.

    2000-04-01

    first lower molar. Microtragulus rusconii (Argirolagida, Argirolagidae is generalized with respect to the other species of this genus in having a less reduced talonid in the m4, and shows closer affinities with M. catamarcensis than with M. reigi. Hyperdidelphys, Lutreolina, Thylatheridium, Achlysictis, and, probably Microtragulus, are common taxa with those of the Valle de Santa María and Puerta de Corral Quemado, in Catamarca province (northwestern Argentina. On the contrary, Pliolestes and Zygolestes constitute exclusive taxa of Cerro Azul Fm. for central Argentina during the Huayquerian Age. The marsupial association recovered from levels of Cerro Azul Fm. is the most abundantly recorded from Upper Miocene levels in South America. Its taxonomic composition confirms previous hypotheses on the important faunal turnover that happened in this continent, as a consequence of the environmental changes occurred since the medial Miocene.Se describe la asociación de marsupiales sudamericanos fósiles de edad Huayqueriense (Mioceno tardío más completa hasta ahora conocida. Los ejemplares fueron exhumados de varias localidades fosilíferas nuevas del centro y norte de la provincia de La Pampa (Argentina central, en sedimentos asignables a la Formación Cerro Azul: Bajo Giuliani, Quehué, Telén, El Guanaco y Laguna Chillhué. El conjunto de las sedimentitas loessoides analizadas en los diferentes afloramientos de esta formación indica la existencia de depósitos lacustres en la base, a los que suprayacen niveles eólicos, ambos con evidencias pedogenéticas. El análisis de estas sedimentitas en cada una de las localidades estudiadas, permitió correlacionarlas en un perfil integrado de la Formación Cerro Azul. Esta formación es correlacionable con la «Formación Epecuén», al menos en la localidad Salinas Grandes de Hidalgo y, probablemente, con los términos superiores de la Formación Arroyo Chasicó. Los marsupiales fósiles exhumados representan la casi

  12. Parabolic trough Project in Cerro Prieto, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lentz, A.; Cadenas, R.; Almanza, R.; Martinez, I.; Ruiz, V.

    2006-07-01

    Federal Electricity Commission (CFE), the most important electricity Company in Mexico wants to install a parabolic trough row in the Cerro Prieto Geothermal field. Cerro Prieto (CP) is the most important geothermal field in Mexico; this area has the highest levels of irradiance in the country. The levels of irradiance make it feasible to set up a solar collector field in the geothermal field to build a hybrid system in order to increase the steam and electricity production. There are several alternative in the hybrid system, depending where the solar field place is located. Two new options are presented in this paper. The first one uses water from the condenser in DSG with the solar field and steam is separated in the first separator. The second option (DSG), the steam produced is separated in an expansion vessel; the water is reinjected in the solar field and the steam goes to the turbine. This project plans to install an experimental facility to research and learning about the technology, CFE main objective will be the electricity generation; using steam from solar collectors using the existing turbines in CPIV; the second objective is to instruct the workers in the operation of the real facility. The third objective is to study the geothermal flow in the absorbers in Direct Steam Generation (DSG), which has salt and silica dissolved, and look for a possible solution for steam generation. The geothermal facilities have considerable experience using the brine flow, so it is not considered an impediment in the solar-geothermal hybrid system. (Author)

  13. Seismological studies at the Cerro Prieto field, 1978 - 1982

    Science.gov (United States)

    Majer, E. L.; McEvilly, T. V.

    1982-10-01

    Varied seismological studies were conducted to determine the static and dynamic properties of the Cerro Prieto geothermal field. Sought were the relation of wave propagation characteristics and microearthquake activity to such features as production boundaries, recharge zones, heat sources, fluid strata, lithology and structure. Discussed are the results of the studies carried out since 1978 in light of the current knowledge of the Cerro Prieto field. Also included are interpretations of the reflection surveys carried out in the immediate production areas.

  14. Soria 2: Apuntes sobre un sitio Formativo en el valle de Yocavil (Catamarca, Argentina Soria 2: Notes on a formative site in the yocavil valley (Catamarca Province, Argentina

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    Valeria Palamarczuk

    2007-12-01

    Full Text Available En este trabajo se presenta información preliminar sobre el sitio arqueológico Soria 2 de la localidad de Andalhuala Banda, correspondiente al Período Temprano en el sur del valle de Yocavil, provincia de Catamarca, Argentina. Un fechado marca un momento de la ocupación inicial del sitio en 1940 + 80 años radiocarbónicos AP, dato particularmente interesante por tratarse de uno de los pocos contextos de carácter doméstico conocidos hasta el momento para los inicios del primer milenio en el sur de Yocavil que han podido ser fechados. La excavación permitió reconocer dos recintos cuyos trazados eran parcialmente visibles en superficie. Dentro de estos se definió un piso de gran espesor con abundante material cerámico, lítico y faunístico, que presentaba diversos rasgos como un fogón, varios agujeros de poste y un pozo de basura -que contenía, entre otros muchos materiales, los restos de un hornillo de pipa cerámica-. Se hallaron también dos entierros primarios de neonatos en ollas de tipo doméstico y el entierro secundario de un párvulo, presentando ajuar. Este aporte junto con futuros trabajos en la zona permitirá bosquejar aspectos de la vida cotidiana de las sociedades agropastoriles tempranas en la región que permanecen esquivos al conocimiento actual.This report presents preliminary information on the Early Period archaeological site of Soria 2 in the locality of Andalhuala Banda in the south of Yocavil Valley ( Catamarca Province, Argentina. A radiocarbon date of 1940 ± 80 radiocarbon years BP marks one moment of the initial site occupation. This information is particularly revealing as it represents one of the few successfully dated domestic-use contexts that dates to the beginning of the first millennium in the south of Yocavil. Through excavation it was possible to identify two occupation units that were only partially detectable on the surface due to poor visibility. A thick and rich stratum was defined within these

  15. Hábitos alimentarios de adultos mayores de dos regiones de la Provincia de Catamarca, Argentina Older adults' eating habits in two regions of Catamarca, Argentina

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    MA Cornatosky

    2009-12-01

    Full Text Available Este trabajo describe los hábitos alimentarios en una población de adultos mayores de la Región Este (RE y Región Oeste (RO de la provincia de Catamarca, Argentina. Estudio epidemiológico, descriptivo y transversal en una muestra aleatoria (n=135 de adultos mayores (60-79 años de ambos sexos. Para recolectar la información sobre hábitos alimentarios se construyó un cuestionario de frecuencia de consumo de alimentos (CFCA cualitativo de una serie seleccionada de alimentos protectores y de riesgo, asociados a ECNT. La frecuencia se categorizó en: Nula; Alta ; Moderada y Baja. La diferencia entre frecuencia de consumo de alimentos se cuantificó mediante el cálculo de proporciones con nivel de significación de 0,01.Para el tratamiento de los datos se empleó el paquete estadístico SPSS ( Statistical Package for the Social Science para Windows versión 10,0 e InfoStat versión 2009 p Se observó que la población de la RO realiza una elección de alimentos más saludables, caracterizada por una mayor variedad y frecuencia de consumo diario de alimentos "protectores" con capacidad antioxidante, que el visto en el colectivo de la RE. Los alimentos de "riesgo", ricos en carbohidratos simples y grasas saturadas, mostraron frecuencias de consumo similares entre ambas poblaciones. Los resultados no expresarían evidencias suficientes para relacionarlos independientemente con morbimortalidad por ECNT. Se ha postulado que los hábitos alimentarios adquiridos durante la infancia persisten en la edad adulta; sin embargo resulta particularmente importante, difundir que los adultos mayores adopten prácticas alimenticias y estilos de vida que minimicen el riesgo adicional de mala salud y potencien las perspectivas de un envejecimiento activo y saludable.This work describes the eating habits of an older adult population in the Eastern region (ER and Western region (WR of Catamarca, Argentina. It is an epidemiologic, descriptive and transversal study

  16. Evaluation of geologic characteristics at Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.H.; Halfman, S.E.; Vonder Haar, S.P.

    1981-01-01

    Computerized well-log analysis of Cerro Prieto has led to the identification of a relatively large and irregular low-density volume extending from near the surface in the vicinity of Laguna Volcano to greater depths toward the northeast. This low-density volume is located about a plane of symmetry of a self-potential anomaly and a group of northeast trending active faults. The presence of a volume of relatively high-density rock has been recognized at shallow depths in the initially developed part of the resource. It is believed to be due to minerals deposited by cooled, rising geothermal brine. Storativity calculated from well logs at the south end of the western part of the field shows acceptable comparison with storativity calculated from well tests. The amount of fluid produced from the field during the period 1973-1977 is greater than the amount in situ calculated from the completed interval thicknesses. Because this part of the field is still producing today, fluid must be recharging this part of the field.

  17. La pobreza y su relación con los problemas de empleo en Catamarca y Tucumán, Argentina, a fines del siglo xx

    OpenAIRE

    Ariel Osatinsky

    2013-01-01

    En 2001 Catamarca era la provincia con menores niveles de pobreza de todo el norte argentino. Por el contrario en Tucumán, cuya economía era la más dinámica de la región, era mayor el porcentaje de hogares pobres. Teniendo en cuenta que entre los procesos económicos y la pobreza existe un fuerte vínculo, y que las dificultades laborales son un componente importante en dicha relación, en este artículo se analiza de qué manera los menores niveles de pobreza en Catamarca fueron consecuencia de q...

  18. Diatomeas (Bacillariophyceae de Ambientes Acuáticos de Altura de la Provincia de Catamarca, Argentina II Diatoms (Bacillariophyceae from high altitude aquatic environments of Catamarca Province in Argentina. II

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    Nora I. Maidana

    2006-07-01

    Full Text Available En esta contribución al conocimiento de las diatomeas de humedales de altura, se analizaron 14 muestras pertenecientes a distintos cuerpos de agua de la Provincia de Catamarca (Argentina, entre los 2420 y 4240 m s. n. m. Se identificaron 208 taxones infragenéricos de los cuales 90 son nuevas citas para la Provincia de Catamarca. Se mencionan por primera vez para Argentina los géneros: Frankophila y Microcostatus y las especies: Achnanthes thermalis var. rumrichorum Lange-Bertalot; Amphora mira Krasske; Brachysira atacamae Hustedt; Frankophila similioides Lange-Bertalot & Rumrich; Gomphonema punae Lange-Bertalot & Rumrich; Haloroundia speciosa Diaz & Maidana; Luticola mollis Lange-Bertalot& Rumrich; Mastogloia atacamae Hustedt; Microcostatus andinus Lange-Bertalot & Rumrich; Navicula atacamana Patrick; Navicula parinacota Rumrich & Lange-Bertalot; Planothidium chilense (Hustedt Lange-Bertalot; Staurosira pseudoconstruens (Marciniak Lange-Bertalot; Surirella chilensis var constricta Hustedt y Surirella wetzellii Hustedt. Además se propone una nueva combinación: Ulnaria ulna var. constricta.In this research focusing the diatoms of high topographic wetlands, 14 samples of different freshwater bodies (between 2,420 and 4,240 m a. s. l. were studied. Two hundred and eight infrageneric taxa were identified, 90 of them are new records for the Catamarca province. The genera: Frankophila and Microcostatus and the species Achnanthes thermalis var. rumrichorum Lange-Bertalot; Amphora mira Krasske; Brachysira atacamae Hustedt; Frankophila similioides Lange-Bertalot & Rumrich; Gomphonema punae Lange-Bertalot & Rumrich; Haloroundia speciosa Diaz & Maidana; Luticola mollis Lange-Bertalot & Rumrich; Mastogloia atacamae Hustedt; Microcostatus andinus Lange-Bertalot& Rumrich; Navicula atacamana Patrick; Navicula parinacota Rumrich & Lange-Bertalot; Planothidium chilense (Hustedt Lange-Bertalot; Staurosira pseudoconstruens (Marciniak Lange-Bertalot; Surirella

  19. [Weight-for-age percentile curves for the population of Catamarca province (Argentina)].

    Science.gov (United States)

    López Barbancho, Diego; Terán de Frutos, José Manuel; Candelas González, Nieves; Díaz de Luna, María Cristina; Marrodán Serrano, María Dolores; Lomaglio, Delia Beatriz

    2014-09-12

    Introducción: La evaluación del desarrollo fetal y del peso al nacimiento es un objetivo prioritario en el ámbito de la epidemiología nutricional y de la salud pública. En la actualidad, la Organización Mundial de la Salud (OMS) no dispone de curvas específicas de peso al nacimiento para las distintas semanas gestacionales al considerar que las características socioeconómicas, ecológicas y étnicas de los distintos grupos humanos influyen en sus propios patrones de crecimiento. Objetivo: La presente investigación desarrolla las curvas percentilares de peso por edad gestacional para las poblaciones residentes en la provincia de Catamarca. Métodos: El procesamiento de los datos se llevó a cabo con el programa SPSS y para la posterior realización de las curvas percentilares se utilizó el programa LMS Chart Maker pro, a partir de un total de 22.576 nacimientos ocurridos entre 1994 y 2003. Discusión y conclusiones: Dichas curvas posibilitarán en el futuro una mejor valoración del desarrollo intrauterino y del peso de los recién nacidos en esta región del Noroeste de Argentina.

  20. Transport of Cerro Hudson SO2 clouds

    Science.gov (United States)

    Doiron, Scott D.; Bluth, Gregg J. S.; Schnetzler, Charles C.; Krueger, Arlin J.; Walter, Louis S.

    The Cerro Hudson volcano in southern Chile (45.92°S, 73.0°W) emitted large ash and sulfur dioxide clouds on August 12-15, following several days of minor activity [Global Volcanism Network Bulletin, 1991]. The SO2 clouds were observed using (preliminary) near real-time data from the Total Ozone Mapping Spectrometer (TOMS) as they encircled the south polar region. The injection of SO2 into the stratosphere has essentially created a gigantic chemical tracer that could provide new insights into the wind patterns and seasonal circulation around the Antarctic region.around the Antarctic region. The TOMS instrument, on board the National Aeronautic and Space Administration's Nimbus 7 satellite, measures the ratio of backscattered Earth radiance to incoming solar irradiance in the ultraviolet spectrum. Although originally designed to measure ozone, it was later discovered that the TOMS instrument could also detect and quantify SO2 [Krueger, 1985]. After this discovery, measurements from TOMS were examined for SO2 emissions for all recorded volcanic eruptions since Nimbus-7 was launched in October 1978, and current data are analyzed as new eruptions occur. The satellite is in a polar, Sun-synchronous orbit so that it crosses the equator at local noon and observes the whole sunlit Earth in approximately 14 orbits each day. Total column amounts of SO2 are determined that represent the amount of gas affecting the reflection of ultraviolet light through a column of the atmosphere from the satellite to the reflecting surface, Earth, given in terms of milli atmospheres centimeter (1000 milli atm cm = a gas layer 1-cm thick at STP). The mass of SO2 is calculated by integrating over the cloud area to obtain a volume, then converting to tons.

  1. Los diques comendíticos de Papachacra (Catamarca: magmatismo peralcalino en sierras Pampeanas orientales The comenditic dikes from Papachacra (Catamarca: peralkaline magmatism in Eastern Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    Fernando Colombo

    2010-03-01

    Full Text Available En Papachacra (Provincia de Catamarca, NO de Argentina hay un plutón compuesto por varios tipos diferentes de granitoides de tipo A con afinidad alcalina. Las rocas más tardías son riolitas peralcalinas (comenditas, que forman diques de hasta 50 cm atravesando el granito biotítico El Portezuelo, el cual está genéticamente desvinculado. Tienen textura porfírica y están compuestas por fenocristales de feldespato potásico (Or97-98 Ab2-3 y egirina (Ac94-98 en una mesostasis afanítica de cuarzo, feldespato potásico, albita, egirina y anfíbol litífero relacionado a la flúor-ferro-leakeíta. Los minerales accesorios son ilmenita, magnetita, óxidos del grupo del pirocloro, epidoto rico en tierras raras, zircón intersticial, monacita- (Ce y un óxido de Nb-Y-Fe no identificado. El contenido de SiO2 varía entre 68,28 y 69,33%, con muy bajo Mg, Ca, Ba, Sr y Eu, y altas concentraciones de Nb (399-409 ppm, Ta (16-34 ppm, Th (46-84 ppm, Y (101-192 ppm, Zn (280-320 ppm, Ga (42-47 ppm y especialmente Zr (2324-3000 ppm. Las comenditas se intruyeron durante un evento magmático anorogénico. Un estudio isotópico (Rb-Sr de reconocimiento hecho a rocas relacionadas indica una edad de 295 + 8 Ma, con una relación 87Sr/86Sr inicial cercana a 0,7041, lo que apunta a una fuente del manto sublitosférico o la base de la corteza inferior. Estas rocas pertenecen a la clase A1 de granitos de tipo A, sugiriendo un origen relacionado a rifting o a puntos calientes, y sus relaciones de elementos trazas muestran afinidades con fundidos relacionados a basaltos de islas oceánicas. En este sentido son diferentes de todos los granitos de tipo A post-devónicos descriptos en Sierras Pampeanas Orientales.In Papachacra (Catamarca Province, NW Argentina there is a pluton composed of several different A-type granitoids that show alkaline affinities. The latest rocks are peralkaline rhyolites (comendites, which form dikes up to 50 cm thick cross-cutting the

  2. Indicadores nutricionales en la población infanto-juvenil de Antofagasta de la Sierra, Catamarca

    OpenAIRE

    Lomaglio, Delia Beatriz; Jalil-Colomé, J.; Lejtman, N.

    2003-01-01

    Antofagasta de la Sierra está ubicada en el NO de la provincia de Catamarca en la región de Puna, a alturas superiores a 3000 metros sobre el nivel del mar. Con el objeto de conocer el estado nutricional de la población infanto- juvenil se obtuvieron las medidas de peso y estatura, las que fueron convertidas a puntajes z y se calcularon los índices P/E, T/E y P/T. Los índices nutricionales fueron comparados con las tablas del NCHS. Se observó prevalencia alta de baja talla y prevalencia... de...

  3. Espacio de asentamiento y campos visuales en la arqueología del Valle de Ambato, Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    Susana Assandri

    2010-10-01

    Full Text Available Aguada culture in Ambato valley, Catamarca, acquires a particular manifestation observed spatially by the large number and variety of settlement units by their external characteristics such as location in relation to land and water resources, and its internal characteristics. It attempts to advance in spatial analysis; we had focused on the internal characteristics of the structures built in the Valley, to deepen their relations with their geographical space as a spatial manifestation of the relationship between humans and their environment. The proposal is that through the analysis of visibility, each of the structures, contribute to the knowledge of the factors contributing to its location in the field.

  4. Crecimiento y nutrición de la población infanto-adolescente de Azampay (Catamarca)

    OpenAIRE

    Padula, Gisel; Tobisch, Alejandro C.; Salceda, Susana Alicia

    2004-01-01

    A partir de 1995 se constituyó un grupo multidisciplinario, que desarrolló sus investigaciones en la localidad de Azampay (Catamarca), abordando el estudio integral de la problemática bio-socio-cultural de las comunidades actuales y arqueológicas con el objetivo de caracterizar procesos de largo plazo. La elección de la localidad de Azampay se realizó en función de su claro rol estratégico a nivel arqueológico, como proveedor de alimentos durante el Período de Desarrollos Regionales, así como...

  5. Del valle al cerro: el sitio del Cerro Zapotecas durante el Epiclásico

    OpenAIRE

    Salomón Salazar, María Teresa

    2008-01-01

    El objetivo de esta tesis es definir qué tipo de asentamiento era el Cerro Zapotecas durante el periodo Epiclásico (600-900 d.C.), ubicado a escasos tres kilómetros de Cholula. Los antecedentes de investigación en este sitio lo señalan como un centro focal de las actividades del valle de Puebla-Tlaxcala durante la transición del Clásico al Posclásico. Esta investigación llevó a cabo un nuevo recorrido de superficie con el cual se documentó la composición arquitectónica y ...

  6. Geophysical monitoring at the Cerro Prieto geothermal field

    Science.gov (United States)

    Wilt, M.; Zelwer, R.; Majer, E. L.

    1982-09-01

    A program of reservoir monitoring at the Cerro Prieto geothermal field using surface geophysical methods with the objective of observing changes resulting from production is described. The three methods used, dipole-dipole resistivity, precision gravity, and passive seismic monitoring, are discussed.

  7. EL CAMINO DEL INKA EN EL SECTOR CENTRAL DE LA PROVINCIA DE CATAMARCA: ACTUALIZACIÓN Y PERSPECTIVAS

    Directory of Open Access Journals (Sweden)

    Reinaldo Andr\\u00E9s Moralejo

    2012-01-01

    Full Text Available Este trabajo tiene como objetivo presentar las últimas investigaciones referentes a la vialidad incaica en el valle del Río Quimivil y en el interfluvio montañoso de la Sierra de Zapata de la provincia de Catamarca. La metodología empleada consistió en el reconocimiento empírico de los caminos y sus componentes asociados, ya sean sitios o asentamientos, materiales en superficie, elementos constitutivos del paisaje, entre otros. El sitio El Shincal ha sido tomado como asentamiento-eje a partir del cual se separan dos caminos Inkas, uno en dirección al Valle de Abaucán por la Cuesta de Zapata, y otro en dirección a los campos agrícolas de Las Vallas a través del valle del Río Quimivil. De esta forma es posible incorporar nuevas rutas de comunicación en este sector de la provincia de Catamarca y comenzar a establecer los vínculos sociales interregionales para el momento de expansión incaica.

  8. Variación regional del crecimiento y estado nutricional: Catamarca

    Directory of Open Access Journals (Sweden)

    Lomaglio, Delia Beatriz

    2005-01-01

    Full Text Available La descripción y el análisis del crecimiento humano han ocupado gran parte de las investigaciones de antropobiólogos, médicos y biólogos humanos, entre otros. En Argentina si bien se dispone de información de prevalencias de malnutrición, existe dificultad en la comparación debido a que en la mayor parte de los casos hay disparidad en las técnicas y/o metodologías empleadas. El objetivo del presente trabajo es analizar el estado nutricional de la población de Catamarca a fin de disponer de elementos diagnósticos que permitan su contrastación con otras provincias argentinas. Peso corporal (kg. y talla (cm. fueron medidos en una muestra de 3328 escolares (1827 varones y 1501 mujeres. Con los datos obtenidos se analizaron los indicadores Peso/Edad (P/E, Peso/Talla (P/T, Talla/Edad (T/E e Indice de Masa Corporal (IMC. La prevalencia de cada indicador se calculó siguiendo los puntos de corte recomendados por la OMS: para bajo P/E, T/E y P/T se utilizó el percentilo 5, para sobrepeso (S el intervalo percentilar 85-95 (>P85 IMC P95. Los resultados obtenidos indicaron las siguientes prevalencias totales: Desnutrición: 24,88%, Bajo P/E: 9,19%, Baja T/E: 9,35%, Bajo P/T: 5,86%, S: 9,58% y O: 4,36%. Los resultados obtenidos indican que, de acuerdo a la OMS, la población evaluada pertenece a un grupo de prevalencia baja tanto para Bajo P/E como para Baja T/E, siendo moderados los porcentajes de sobrepeso y obesidad.

  9. Los diques comendíticos de Papachacra (Catamarca: magmatismo peralcalino en sierras Pampeanas orientales

    Directory of Open Access Journals (Sweden)

    Fernando Colombo

    2010-03-01

    Full Text Available En Papachacra (Provincia de Catamarca, NO de Argentina hay un plutón compuesto por varios tipos diferentes de granitoides de tipo A con afinidad alcalina. Las rocas más tardías son riolitas peralcalinas (comenditas, que forman diques de hasta 50 cm atravesando el granito biotítico El Portezuelo, el cual está genéticamente desvinculado. Tienen textura porfírica y están compuestas por fenocristales de feldespato potásico (Or97-98 Ab2-3 y egirina (Ac94-98 en una mesostasis afanítica de cuarzo, feldespato potásico, albita, egirina y anfíbol litífero relacionado a la flúor-ferro-leakeíta. Los minerales accesorios son ilmenita, magnetita, óxidos del grupo del pirocloro, epidoto rico en tierras raras, zircón intersticial, monacita- (Ce y un óxido de Nb-Y-Fe no identificado. El contenido de SiO2 varía entre 68,28 y 69,33%, con muy bajo Mg, Ca, Ba, Sr y Eu, y altas concentraciones de Nb (399-409 ppm, Ta (16-34 ppm, Th (46-84 ppm, Y (101-192 ppm, Zn (280-320 ppm, Ga (42-47 ppm y especialmente Zr (2324-3000 ppm. Las comenditas se intruyeron durante un evento magmático anorogénico. Un estudio isotópico (Rb-Sr de reconocimiento hecho a rocas relacionadas indica una edad de 295 + 8 Ma, con una relación 87Sr/86Sr inicial cercana a 0,7041, lo que apunta a una fuente del manto sublitosférico o la base de la corteza inferior. Estas rocas pertenecen a la clase A1 de granitos de tipo A, sugiriendo un origen relacionado a rifting o a puntos calientes, y sus relaciones de elementos trazas muestran afinidades con fundidos relacionados a basaltos de islas oceánicas. En este sentido son diferentes de todos los granitos de tipo A post-devónicos descriptos en Sierras Pampeanas Orientales.

  10. El extremo rico en As de la serie jordanita-geocronita de Mina Capillitas, Catamarca

    Directory of Open Access Journals (Sweden)

    M.F. Márquez-Zavalía

    2006-06-01

    Full Text Available Jordanita, Pb14As6S23, el extremo rico en As de la serie jordanita-geocronita, fue encontrado en veta Bordón, en mina Capillitas, un depósito epitermal vetiforme de metales preciosos y básicos, ubicado en la ladera oriental de la sierra de Capillitas, Catamarca. Se presenta asociado a esfalerita, marcasita y galena en cristales anhedrales, equidimensionales y en agrupaciones microcristalinas de hasta 5 mm; es frágil y su dureza es ~3. Bajo el microscopio de polarización y observándolo con luz reflejada, es un mineral blanco con débil birreflectancia y pleocroismo (blanco brillante a blanco con leve tonalidad grisácea, con dureza de pulido menor que la de esfalerita y poder reflector alto, similar al de galena. La jordanita tiene anisotropía distintiva; sus colores de polarización, en aire, son verde azulado y violeta con suave tonalidad ocrácea. Su composición química, expresada en porcentaje en peso (min-máx-promedio es: S: 17,20-18,49-17,84; As: 10,32-11,44-10,88, Pb: 70,60-71,46-71,03 y Sb: 0,00%. La fórmula estructural, calculada en base a 43 átomos por celda unidad, es: Pb14.20As5.80S23.00. La jordanita tiene simetría monoclínica y grupo espacial P21/m; sus líneas de difracción de rayos X más intensas son: (dÅ, hkl, I/Io: 2,287, 1 12 1, 100; 1,819, -1 17 1, 80; 3,17, 2 6 0, 60; 2,111, -2 1 4, 50. Los parámetros de su celda unidad, refinados a partir de datos de difractogramas de polvo usando CELREF, son: a = 8,933 (2 Å, b = 31,869 (4 Å, c = 8,458 (1 Å, ß = 117,17°, V = 2131 (1 Å3.

  11. Brine treatment test for reinjection on Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Hurtado, R.; Mercado, S.; Gamino, H. (Departamento de Geotermia, Division de Fuentes de Energia, Instituto de Investigaciones Electricas, Justo Sierra y Herreros Sur 2098-Altos C.P. 21020, Mexicali, B.C. (MX))

    1989-01-01

    Reinjection of disposal brine from the Cerro Prieto Geothermal Power Plant System is attractive mainly because, on top of solving the brine disposal problem, it may significantly contribute to extend the reservoir useful lifetime, through thermal and hydraulic recharge. Because the high concentration of colloidal silica in the disposal brine, laboratory and pilot plant tests were conducted in order to develop the brine treatment process. Addition of 20-40 mg/1 lime to flashed and aged brine for 10-20 minutes yields a clarified brine relatively low in suspended solids (10-30 mg/1) when the over flow rate is 38.5 1/min-m/sup 2/. 1.1 mills/kWh was the estimated cost for treatment of 800 kg/s of separated brine from the Cerro Prieto I power station.

  12. Criteria for determining casing depth in Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Olivas M., H.M.; Vaca S., J.M.E.

    1982-08-10

    On the basis of geological data obtained during drilling and its relation to electric logs, together with the problems that arose when drilling through formations until the production zone was reached, it is possible to establish the most suitable manner to line a well and thus formulate an optimum casings program. The main criteria to be taken into consideration in preparing such a program and its application in the drilling of wells programmed in Cerro Prieto to optimize and economize such drilling and achieve suitable techniques for well completion are presented. The criteria are based on the characteristics of the Cerro Prieto field and on casing design factors, as well as a experience gained during drilling in such a field.

  13. El ajuar como indicador de la presencia Inka en el Cementerio Aguada Orilla Norte (Provincia de Catamarca Grave Goods As Indicators Of Inka Presence In Aguada Orilla Norte Cementery, Catamarca Province

    Directory of Open Access Journals (Sweden)

    Reinaldo A. Moralejo

    2010-12-01

    Full Text Available En este trabajo se presenta la descripción del ajuar de cuatro enterratorios provenientes del sitio arqueológico Cementerio Aguada Orilla Norte (Belén, Catamarca. Dichos ajuares conforman la colección Benjamín Muñiz Barreto del Museo de La Plata. La metodología empleada consistió en la descripción morfológica y decorativa de las piezas que conforman cada uno de los ajuares; y en la revisión de las libretas de campo de la colección mencionada. A partir de estos análisis se determinó que tres de los cuatro enterratorios se encuadran cronológicamente en el período Inka (1471-1536 dC y que cada uno de ellos posee objetos estilísticamente diferentes pertenecientes a diversos grupos culturales del NOA. Sin embargo, el cuarto ajuar, que se encuentra por debajo de uno de los anteriores, posee piezas pertenecientes a grupos culturales preinkaicos.This paper describes the grave goods from four burials found at the archaeological site of Aguada Orila Norte Cemetery, Belén, Catamarca. The grave goods belong to the Benjamin Muñiz Barreto collection, housed at the Museum of La Plata. The methodology employed consisted in describing the morphology and decoration of the pieces that make up each set of grave goods, as well as going through the field notes related to the collection. The results of the analyses indicate that three of the four burials are chronologically within the Inka period (AD 1471-1536 and all posses objects that differ in style, belonging therefore to various cultural groups from NOA (Northwestern Argentina. The fourth burial, however, which was located below one of the other three, contains pieces from pre-Inkan cultural groups.

  14. ESPACIO DE ASENTAMIENTO Y CAMPOS VISUALES EN LA ARQUEOLOGÍA DEL VALLE DE AMBATO, CATAMARCA, ARGENTINA / Settlement space and visual fields in the archeology of Ambato valley, Catamarca, Argentina.

    Directory of Open Access Journals (Sweden)

    Susana Assandri

    2010-12-01

    Full Text Available La cultura Aguada en el Valle de Ambato, Catamarca, adquiere una manifestación particular que se observa a nivel espacial por la gran cantidad y variedad de las unidades de asentamiento, tanto por sus características externas, como emplazamiento en el terreno y relación con recursos hídricos, como por sus características internas. En este trabajo se intenta avanzar en el análisis espacial, que habíamos enfocado en las características internas de las estructuras construidas en el Valle, para ahondar en la relación de éstas con su espacio geográfico, como una de las manifestaciones espaciales de las relaciones entre los seres humanos y su ambiente.La propuesta es que a través del análisis de la visibilidad, de cada una de las estructuras, genere un aporte al conocimiento de los factores que contribuyen a su emplazamiento en el terreno. Palabras Clave: Aguada; análisis espacial; visibilidad; estructuras; emplazamiento. AbstractAguada culture in Ambato valley, Catamarca, acquires a particular manifestation observed spatially by the large number and variety of settlement units by their external characteristics such as location in relation to land and water resources, and its internal characteristics.  It attempts to advance in spatial analysis; we had focused on the internal characteristics of the structures built in the Valley, to deepen their relations with their geographical space as a spatial manifestation of the relationship between humans and their environment.  The proposal is that through the analysis of visibility, each of the structures, contribute to the knowledge of the factors contributing to its location in the field. Keywords: Aguada, spatial analysis, visibility, structures, location.

  15. Open file data on the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Lippman, M.J.; Aguirre, B.D.; Wollenberg, H.A.; Witherspoon, P.A.

    1977-04-01

    Some of the unpublished data presently available on open file at the Lawrence Berkeley Laboratory are listed and described. In addition, in the files are a number of internal memoranda of the Commission Federal de Electricidad of Mexico (CFE) on chemical characteristics of the produced fluids and incrustations; published papers on Cerro Prieto and the geologic setting of the Salton Trough; and data on the hydrogeology of the Mexicali Valley. (MHR)

  16. Dating thermal events at Cerro Prieto using fission track annealing

    Energy Technology Data Exchange (ETDEWEB)

    Sanford, S.J.; Elders, W..

    1981-01-01

    Data from laboratory experiments and geologic fading studies were compiled from published sources to produce lines of iso-annealing for apatite in time-temperature space. Fission track ages were calculated for samples from two wells at Cerro Prieto, one with an apparently simple and one with an apparently complex thermal history. Temperatures were estimated by empirical vitrinite reflectance geothermometry, fluid inclusion homogenization and oxygen isotope equilibrium. These estimates were compared with logs of measured borehole temperatures.

  17. Early mineralization at Cerro de Pasco (central Peru) revisited

    OpenAIRE

    Rottier, Bertrand; Casanova, Vincent; Fontboté, Lluis; Kouzmanov, Kalin; Alvarez, Hugo; Bendezú, Ronner

    2013-01-01

    The large Cerro de Pasco Cordilleran base metal deposit in central Peru is located on the eastern margin of a Middle Miocene diatreme-dome complex. A striking characteristic is the presence of a N-S trending massive funnel-shape pyrite-quartz replacement ore body that contains pyrrhotite pipes grading outwards to lead-zinc replacement bodies, along the eastern contact of the diatreme-dome complex. Earlier workers interpreted the pyrrhotite pipes as postdating the pyritequartz body. This study...

  18. Estratigrafia e estrutura do Cerro do Jarau: nova proposta

    Directory of Open Access Journals (Sweden)

    Joana Paula Sánchez

    Full Text Available A estrutura do Cerro do Jarau está localizada no Estado do Rio Grande do Sul, nas proximidades de Quarai, divisa com o Uruguai. É uma estrutura circular de aproximadamente 8 km de diâmetro, cujos dados geológicos apontam para uma origem por impacto meteorítico. Está situada na Bacia do Paraná e compreende uma área de afloramento de arenitos na porção central, circundada por basaltos da Formação Serra Geral. Nos trabalhos publicados, o arenito da porção central é interpretado como pertencente à Formação Botucatu, soerguido em meio aos basaltos da Formação Serra Geral, correspondendo, para muitos autores, a uma feição dômica. O objetivo do presente trabalho é apresentar novos dados sobre a estratigrafia e estrutura do Cerro do Jarau, que mostram que os arenitos estão estrutural e estratigraficamente sobrepostos aos basaltos e ambas unidades exibem mergulhos centrípetos. A estrutura do Cerro do Jarau é, portanto, uma bacia com a porção central rebaixada, e não um domo como antes admitido.

  19. Current state of the hydrothermal geochemistry studies at Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Fausto L, J.J.; Jimenez S, M.E.; Esquer P, I.

    1981-01-01

    The current state of hydrothermal geochemistry studies being carried out at the field are reported. These studies are based on the results of chemical analysis of water samples collected during 1979 and 1980 at the geothermal wells of the area known as Cerro Prieto I, as well as from those located in the Cerro Prieto II and Cerro Prieto III areas, some of which have only recently started flowing. Data are presented on the chemical variations of the main chemical constituents dissolved in the waters, as well as on the Na/K and Na-K-Ca chemical relations and the temperatures calculated from them and from SiO/sub 2/. Fluid recharge into the reservoir and its direction of flow are interpreted from isotherm contour maps of the field prepared from Na/K and Na-K-Ca geothermometry and from concentration contour maps of some of the main chemical constituents. Well M-43 is discussed as an example of a well affected by well completion problems in its production casing. Its behavior is explained on the basis of the chemical characteristics of the produced water. The chemical changes that have taken place in some of the wells during production are explained by correlating the chemistry with the production mechanisms of the well (steam-water production rates).

  20. Correlation between precision gravity and subsidence measurements at Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Zelwer, R.; Grannell, R.B.

    1982-10-01

    Precision gravity measurements were made in the region of the Cerro Prieto geothermal field at yearly intervals from 1977 to 1981 to assess the feasibility of using gravity to determine subsurface reservoir changes with time. The extent of mass recharge in response to the continued production of fluids from this field was studied. Changes in gravity and ground elevation were observed throughout the region for the period of observation. Results indicate that the largest changes observed were the result of the Magnitude 6.1 (Caltech) Victoria earthquake of 8 June 1980. The epicenter of this earthquake was located 25 km southeast of the field on the Cerro Prieto Fault, which bounds the field on the southwest. Subsidence of up to 55 cm was measured east of the power plant, in the region between the northern end of the Cerro Prieto Fault and the southern end of the Imperial Fault. This area has been postulated to be the site of an active spreading center or pull-apart basin, and has been characterized by a high level of seismic activity during the last 10 years. Minor subsidence and small related gravity changes for the period preceeding the Victoria earthquake suggest that in spite of large fluid production rates, the reservoir is being almost completely recharged and that a measurable increase in subsurface density may be taking place. The results of measurements of horizontal ground motions made in this area are discussed in relation to the gravity and subsidence observations.

  1. Microfossils from Cerro Prieto geothermal wells, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, M.L.; Haar, S.V.

    1982-08-10

    To aid in a paleonenvironmental and age reconstruction of the Cerro Prieto reservoir system, 59 samples of well cuttings were analyzed for microfossils. The cuttings were obtained at depths from 351 to 3495m in 14 geothermal wells in the Cerro Prieto field, Baja California, Mexico. Foraminifera was found in 6 samples, ostracodes in 19 samples and mannoplankton as coccoliths in 24 samples. Other groups, such as molluscus, insects, fish skeletal parts, and plant material were occasionally present. Detailed interpretations at this time cannot be made because of poor preservation of samples. This is primarily due to causes: dissolution by geothermal fluids that reach 350/sup 0/C, and the extensive mixing of filled Cretaceous forms (reworked from the Colorado Plateau region) with Tertiary species during drilling. Further studies of ostracodes and foraminifera from colder portions of the wells are needed. The abundant and well-preserved ostracodes indicate marine to backish water inviroments that correspond in part, to lagoonal or estuarine facies. The presence of the mid-Tertiary (15-m.y.-old) marine foraminifera, Cassigerinela chipolensis, in wells M-11 and M-38, 350 to 500m deep, is perplexing. These are not laboratory contaminates and, as yet have not been found in the drilling mud. If further studies confirm their presence at Cerro Prieto, established ideas about the opening of the Gulf of California and about Pacific Coast mid-Tertiary history will need to be rewritten.

  2. Correlation between precision gravity and subsidence measurements at Cerro Prieto

    Science.gov (United States)

    Zelwer, R.; Grannell, R. B.

    1982-10-01

    Precision gravity measurements were made in the region of the Cerro Prieto geothermal field at yearly intervals from 1977 to 1981 to assess the feasibility of using gravity to determine subsurface reservoir changes with time. The extent of mass recharge in response to the continued production of fluids from this field was studied. Changes in gravity and ground elevation were observed throughout the region for the period of observation. Results indicate that the largest changes observed were the result of the Magnitude 6.1 (Caltech) Victoria earthquake of 8 June 1980. The epicenter of this earthquake was located 25 km southeast of the field on the Cerro Prieto Fault, which bounds the field on the southwest. Subsidence of up to 55 cm was measured east of the power plant, in the region between the northern end of the Cerro Prieto Fault and the southern end of the Imperial Fault. This area has been postulated to be the site of an active spreading center or pull-apart basin, and has been characterized by a high level of seismic activity during the last 10 years.

  3. Microfossils from Cerro Prieto geothermal wells, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, M.L.; Vonder Haar, S.

    1980-01-01

    To aid in a paleoenvironmental and age reconstruction of the Cerro Prieto reservoir system, 59 samples of well cuttings were analyzed for microfossils. The cuttings were obtained at depths from 351 to 3495 m in 14 geothermal wells in the Cerro Prieto field, Baja California, Mexico. We found foraminifera in 6 samples, ostracodes in 19 samples, and nannoplankton as coccoliths in 24 samples. Other groups, such as molluscs, insects, fish skeletal parts, and plant material were occasionally present. Detailed interpretations are not possible at this time because of poor preservation of samples. This is primarily due to causes: dissolution by geothermal fluids that reach 350{sup 0}C, and the extensive mixing of filled Cretaceous forms (reworked from the Colorado Plateau region) with Tertiary species during drilling. Further studies of ostracodes and foraminifera from colder portions of the wells are needed. The abundant and well-preserved ostracodes indicate marine to brackish water environments that correspond, in part, to lagoonal or estuarine facies. The presence of the mid-Tertiary (15-My-old) marine foraminifera, Cassigerinela chipolensis, in wells M-11 and M-38, 350 to 500 m deep, is perplexing. These are not laboratory contaminates and, as yet, have not been found in the drilling mud. If further studies confirm their presence at Cerro Prieto, established ideas about the opening of the Gulf of California and about Pacific Coast mid-Tertiary history will need to be rewritten.

  4. Panama Canal Zone. Cerro Tigre, Fort Gulick, Gamboa Met Van No. 1.

    Science.gov (United States)

    The report contains the following meteorological data collected at sites within Fort Gulick and Cerro Tigre , Panama during December 1970: Atmospheric precipitation; Atmospheric temperature; Wind; Atmospheric pressure.

  5. La pobreza y su relación con los problemas de empleo en Catamarca y Tucumán, Argentina, a fines del siglo xx

    Directory of Open Access Journals (Sweden)

    Ariel Osatinsky

    2013-01-01

    Full Text Available En 2001 Catamarca era la provincia con menores niveles de pobreza de todo el norte argentino. Por el contrario en Tucumán, cuya economía era la más dinámica de la región, era mayor el porcentaje de hogares pobres. Teniendo en cuenta que entre los procesos económicos y la pobreza existe un fuerte vínculo, y que las dificultades laborales son un componente importante en dicha relación, en este artículo se analiza de qué manera los menores niveles de pobreza en Catamarca fueron consecuencia de que su población resultó menos afectada que la tucumana por las transformaciones productivas regresivas y los problemas de empleo del periodo.

  6. Seismotectonics of the Cerro Prieto Geothermal Field, Baja California, Mexico.

    Science.gov (United States)

    Rebollar, C. J.; Reyes, L. M.; Quintanar, L.; Arellano, J. F.

    2002-12-01

    We studied the background seismic activity in the Cerro Prieto geothermal field (CPGF) using a network of 21 digital stations. Earthquakes are located below the exploitation area of the CPGF, between 3 and 12 km depth, within the basement. Earthquakes follow roughly a N30°E trend perpendicular to the Cerro Prieto fault. This activity is located on a horst-like structure below the geothermal field and coincides with the zone of maximum subsidence in the CPGF. Two earthquake swarms occurred along the SE-NW strike of the Cerro Prieto fault and in the neighborhood of the Cerro Prieto volcano. Magnitudes range from -0.3 to 2.5. A Vp/Vs=1.91 ratio of the activity below the volcano suggests a water-saturated medium and/or a partial-melt medium. We calculated 76 focal mechanisms of individual events. On June 1 and September 10, 1999, two earthquakes of Mw 5.2 and 5.3 occurred in the basement at depths of 7.4 and 3.8 km below the CPGF. Maximum peak accelerations above the hypocenter ranged from 128.0 to 432.0 cm/s2. Waveform modeling results in a fault geometries given by strike=236°, dip=60°, rake=-58° (normal) and strike=10°, dip=90°, rake=159° (right lateral strike-slip) for the June and September events. Observed triangular source time function of 0.7 seconds and a double source with a total duration of 1.9 seconds for the June and September events were used to calculate the synthetics seismograms. Static stress drops and seismic moments for the June and September events are: Δ\\sigma=82.5 MPa (825 bars), Mo= 7.65x1016 Nm (7.65x1023 dyne-cm) and Δ\\sigma=31.3 MPa (313 bars) and Mo=1.27x1017 Nm (1.27x1024 dyne-cm). These stress drops are typical of continental events rather than stress drops of events originated in spreading centers. We concluded from the focal mechanisms of the background seismicity and June and September 1999 events, that a complex stress environment exits in the CPGF due to the continual thinning of the crust in the Cerro Prieto basin.

  7. Atmospheric conditions at Cerro Armazones derived from astronomical data

    Science.gov (United States)

    Lakićević, Maša; Kimeswenger, Stefan; Noll, Stefan; Kausch, Wolfgang; Unterguggenberger, Stefanie; Kerber, Florian

    2016-04-01

    Aims: We studied the precipitable water vapour (PWV) content near Cerro Armazones and discuss the potential use of our technique of modelling the telluric absorbtion lines for the investigation of other molecular layers. The site is designated for the European Extremely Large Telescope (E-ELT) and the nearby planned site for the Čerenkov Telescope Array (CTA). Methods: Spectroscopic data from the Bochum Echelle Spectroscopic Observer (BESO) instrument were investigated by using a line-by-line radiative transfer model (LBLRTM) for the Earth's atmosphere with the telluric absorption correction tool molecfit. All observations from the archive in the period from December 2008 to the end of 2014 were investigated. The dataset completely covers the El Niño event registered in the period 2009-2010. Models of the 3D Global Data Assimilation System (GDAS) were used for further comparison. Moreover, we present a direct comparison for those days for which data from a similar study with VLT/X-Shooter and microwave radiometer LHATPRO at Cerro Paranal are available. Results: This analysis shows that the site has systematically lower PWV values, even after accounting for the decrease in PWV expected from the higher altitude of the site with respect to Cerro Paranal, using the average atmosphere found with radiosondes. We found that GDAS data are not a suitable basis for predicting local atmospheric conditions - they usually systematically overestimate the PWV values. The large sample furthermore enabled us to characterize the site with respect to symmetry across the sky and variation with the years and within the seasons. This technique of studying the atmospheric conditions is shown to be a promising step into a possible monitoring equipment for the CTA. Based on archival observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile and of the Cerro Armazones Observatory facilities of the Ruhr Universität Bochum.Full Table 1

  8. Connected magma plumbing system between Cerro Negro and El Hoyo Complex, Nicaragua revealed by gravity survey

    Science.gov (United States)

    MacQueen, Patricia; Zurek, Jeffrey; Williams-Jones, Glyn

    2016-11-01

    Cerro Negro, near León, Nicaragua is a young, relatively small basaltic cinder cone volcano that has been unusually active during its short lifespan. Multiple explosive eruptions have deposited significant amounts of ash on León and the surrounding rural communities. While a number of studies investigate the geochemistry and stress regime of the volcano, subsurface structures have only been studied by diffuse soil gas surveys. These studies have raised several questions as to the proper classification of Cerro Negro and its relation to neighboring volcanic features. To address these questions, we collected 119 gravity measurements around Cerro Negro volcano in an attempt to delineate deep structures at the volcano. The resulting complete Bouguer anomaly map revealed local positive gravity anomalies (wavelength 0.5 to 2 km, magnitude +4 mGal) and regional positive (10 km wavelength, magnitudes +10 and +8 mGal) and negative (12 and 6 km wavelength, magnitudes -18 and -13 mGal) Bouguer anomalies. Further analysis of these gravity data through inversion has revealed both local and regional density anomalies that we interpret as intrusive complexes at Cerro Negro and in the Nicaraguan Volcanic Arc. The local density anomalies at Cerro Negro have a density of 2700 kg m-3 (basalt) and are located between -250 and -2000 m above sea level. The distribution of recovered density anomalies suggests that eruptions at Cerro Negro may be tapping an interconnected magma plumbing system beneath El Hoyo, Cerro La Mula, and Cerro Negro, and more than seven other proximal volcanic features, implying that Cerro Negro should be considered the newest cone of a Cerro Negro-El Hoyo volcanic complex.

  9. Exploration and development of the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Lippmann, M.J.; Goldstein, N.E.; Halfman, S.E.; Witherspoon, P.A.

    1983-07-01

    A multidisciplinary effort to locate, delineate, and characterize the geothermal system at Cerro Prieto, Baja California, Mexico, began about 25 years ago. It led to the identification of an important high-temperature, liquid-dominated geothermal system which went into production in 1973. Initially, the effort was undertaken principally by the Mexican electric power agency, the Comision Federal de Electricidad (CFE). Starting in 1977 a group of US organizations sponsored by the US Department of Energy, joined CFE in this endeavor. An evaluation of the different studies carried out at Cerro Prieto has shown that: (1) surface electrical resistivity and seismic reflection surveys are useful in defining targets for exploratory drilling; (2) the mineralogical studies of cores and cuttings and the analysis of well logs are important in designing the completion of wells, identifying geological controls on fluid movement, determining thermal effects and inferring the thermal history of the field; (3) geochemical surveys help to define zones of recharge and paths of fluid migration; and (4) reservoir engineering studies are necessary in establishing the characteristics of the reservoir and in predicting its response to fluid production.

  10. Precision gravity studies at Cerro Prieto: a progress report

    Energy Technology Data Exchange (ETDEWEB)

    Grannell, R.B. (California State Univ., Long Beach); Kroll, R.C.; Wyman, R.M.; Aronstam, P.S.

    1981-01-01

    A third and fourth year of precision gravity data collection and reduction have now been completed at the Cerro Prieto geothermal field. In summary, 66 permanently monumented stations were occupied between December and April of 1979 to 1980 and 1980 to 1981 by a LaCoste and Romberg gravity meter (G300) at least twice, with a minimum of four replicate values obtained each time. Station 20 alternate, a stable base located on Cerro Prieto volcano, was used as the reference base for the third year and all the stations were tied to this base, using four to five hour loops. The field data were reduced to observed gravity values by (1) multiplication with the appropriate calibration factor; (2) removal of calculated tidal effects; (3) calculation of average values at each station, and (4) linear removal of accumulated instrumental drift which remained after carrying out the first three reductions. Following the reduction of values and calculation of gravity differences between individual stations and the base stations, standard deviations were calculated for the averaged occupation values (two to three per station). In addition, pooled variance calculations were carried out to estimate precision for the surveys as a whole.

  11. Hydrocarbons emissions from Cerro Prieto Geothermal Power Plant, Mexico

    Science.gov (United States)

    Navarro, Karina; Navarro-González, Rafael; de la Rosa, José; Peralta, Oscar; Castro, Telma; Imaz, Mireya

    2014-05-01

    One of the most important environmental issues related to the use of geothermal fluids to generate electricity is the emission of non-condensable gases to the atmosphere. Mexico has one of the largest geothermal plants in the world. The facility is located at Cerro Prieto, Baja California, roughly 30 km south of Mexicali and the international boundary between Mexico and United States. The Cerro Prieto power plant has 13 units grouped on four individual powerhouses. Gas samples from 9 units of the four powerhouses were collected during 4 campaigns conducted in May-July, 2010, February, 2012, December, 2012, and May, 2013. Gas samples from the stacks were collected in 1000 ml Pyrex round flasks with Teflon stopcocks, and analyzed by gas chromatography-mass spectrometry. Methane was the most abundant aliphatic hydrocarbon, with a concentration that ranged from less than 1% up to 3.5% of the total gas mixture. Normal alkanes represented the second most abundant species, and displayed a decreasing abundance with increasing carbon number in the homologous series. Isoalkanes were also present as isobutane and isopentane. Cycloalkanes occurring as cyclopentane and cyclohexane, were detected only at trace level. Unsaturated hydrocarbons (alkenes and alkynes) were not detected. Benzene was detected at levels ranging from less than 1% up to 3.4% of the total gas mixture. Other aromatic hydrocarbons detected were toluene, and xylenes, and were present at lower concentrations (

  12. Characterization of pottery from Cerro de Las Ventanas, Zacatecas, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-del-Rio, H.; Mireles-Garcia, F. [Unidad Academica de Estudios Nucleares, UAZ, Zacatecas (Mexico); Mendez-Cardona, R.Y. [Unidad Academica de Antropologia, UAZ, Zacatecas (Mexico); Nicolas-Caretta, M. [INAH Delegacion Zacatecas (Mexico); Coordinacion de Ciencias Sociales y Humanidades, UASLP, Fracc. Talleres, SLP (Mexico); Speakman, R.J. [Museum Conservation Inst., Smithsonian Institution, Suitland, MD (United States); Glascock, M.D. [Research Reactor Center, Univ. of Missouri, Columbia, MO (United States)

    2009-09-15

    With the aim of classifying prehispanic pottery from Cerro de Las Ventanas site, Juchipila, Zacatecas, Mexico, instrumental neutron activation analysis (INAA) was used to analyze ceramic samples at the University of Missouri Research Reactor Center. Thirty-two chemical elements were measured: Al, As, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Ti, Th, U, V, Yb, Zn, and Zr. Two multivariate statistical methods, cluster analysis and principal component analysis, were performed on the dataset to examine similarities between samples and to establish compositional groups. The statistical analyses of the dataset suggest that the pottery samples form a unique chemically homogeneous group, with the exception of one pottery sample. The compositional data were compared to an existing Mesoamerican ceramic database. It was found that the newly generated data fit best with data from a previous chemical analysis of pottery from the Malpaso Valley. However, despite the apparent similarity, pottery samples from the site of Cerro de Las Ventanas represent a new and unique chemical fingerprint in the region. (orig.)

  13. Macros y atajos para el traductor

    OpenAIRE

    José Luis Heredero

    2007-01-01

    Sin necesidad de recurrir a los productos comerciales de ayuda a la traducción que se han ido generalizando en muchas grandes empresas y organizaciones, el traductor independiente puede ver considerablemente facilitado su trabajo si sabe explotar las muchas posibilidades que brindan Visual Basic y otros lenguajes poco conocidos de dominio público. Se presentan aquí varias macros de Word y pequeñas aplicaciones desarrolladas en los últimos años para acelerar tanto las búsquedas de términos —ba...

  14. A large eruption convulsed in prehistoric times an extensive area of Catamarca, Southern Central Andes, NW Argentina

    Science.gov (United States)

    Fernandez-Turiel, Jose-Luis; Ratto, Norma; Perez-Torrado, Francisco-Jose; Rodriguez-Gonzalez, Alejandro; Rejas, Marta; Lobo, Agustin

    2016-04-01

    Geomorphological, stratigraphical, mineralogical and chemical characteristics of many recent 30-160 cm ash deposits occurring at the Bolsón de Fiambalá in Catamarca, NW Argentina, allow their correlation. This lithostratigraphic unit is named Fiambalá Ash and it is uncovered or covered by colluvial deposits and present-day aeolian deposits, reworked products of the primary fall deposits. The grain size of these ash deposits is gritty rather than silty. They are nearly unique among regional ashes in containing hornblende phenocrysts. In addition, they are made up of glass (subangular blocky shards), feldspars, biotite, and quartz; magnetite, ilmenite, apatite and titanite are scarce. The glass is rhyolitic (˜75 to 79 % m/m SiO2; ˜3 to 4 % m/m Na2O; ˜3 to 5 % m/m K2O; 1 to 2 % m/m CaO; normalized to 100 %). On the other hand, in northern margins of Fiambalá basin, extensive remnants of fines-poor pumiceous debris flows and hyperconcentrated sandflow deposits as thick as 10 m are exposed on the walls of the river gorges, where the base is usually covered, e.g., Chuquisaca River. There is no significant unconformity or intercalation of other materials, thus suggesting rapid emplacement after a single eruptive event. A preliminary age of Fiambalá Ash based on archaeological studies bracket it between 1400-1270 and 1270-980 cal a BP (OxCal 4.2.4, SHCal13, 2 sigma). The geographical distribution, the geomorphological features observed in satellite images and the information on the main trends of the stratigraphy, the abundance of hornblende and biotite in the younger proximal ash fall deposits, ignimbrites and lava-domes of the Nevado Tres Cruces complex, favours this edifice as the strongest candidate to be the source of the Upper Holocene pyroclastic deposits found in the Fiambalá basin. The archaeological records seem to evidence the abrupt environmental and societal changes associated with this major eruption. Significant areas of Catamarca were likely

  15. Indicadores nutricionales en la población infanto-juvenil de Antofagasta de la Sierra, Catamarca

    Directory of Open Access Journals (Sweden)

    Lomaglio, Delia Beatriz

    2003-01-01

    Full Text Available Antofagasta de la Sierra está ubicada en el NO de la provincia de Catamarca en la región de Puna, a alturas superiores a 3000 metros sobre el nivel del mar. Con el objeto de conocer el estado nutricional de la población infanto- juvenil se obtuvieron las medidas de peso y estatura, las que fueron convertidas a puntajes z y se calcularon los índices P/E, T/E y P/T. Los índices nutricionales fueron comparados con las tablas del NCHS. Se observó prevalencia alta de baja talla y prevalencia... de bajo peso. Si bien es conocido el efecto de la hipoxia de alturas extremas sobre el crecimiento, en el caso de Antofagasta de la Sierra se asocian otros factores, en general presentes también en otras poblaciones de altura, como condiciones sanitarias, socio-económicas y nutricionales deficitarias y que dificultan el análisis.

  16. A review of progress in understanding the fluid geochemistry of the Cerro Prieto geothermal system

    Science.gov (United States)

    Truesdell, A.H.; Nehring, N.L.; Thompson, J.M.; Janik, C.J.; Coplen, T.B.

    1984-01-01

    Fluid geochemistry has played a major role in our present understanding of the Cerro Prieto geothermal system. Fluid chemical and isotopic compositions have been used to indicate the origin of water, salts and gases, original subsurface temperature and fluid flow, fluid-production mechanisms, and production-induced aquifer boiling and cold-water entry. The extensive geochemical data and interpretations for Cerro Prieto published from 1964 to 1981 are reviewed and discussed. Fluid geochemistry must continue to play an important role in the further development of the Cerro Prieto field. ?? 1984.

  17. Progress on the biphase turbine at Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Cerini, D.; Hays, L.; Studhalter, W. [Douglas Energy Company, Placentia, CA (United States)

    1997-12-31

    The status of a Biphase turbine power plant being installed at the Cerro Prieto geothermal field is presented. The major modules for the power plant are completed except for a back pressure steam turbine. The power plant will be started in April 1997 with the Biphase turbine alone followed by the addition of the steam turbine module two months later. The current power plant performance level is 2780 kWe due to a decline in the well. An increase in power output to 4060 kWe by adding the flow from another well is planned. The addition of five Biphase power plants with a total power output of 21.2 megawatts is described.

  18. Geochemical evidence of drawdown in the Cerro Prieto geothermal field

    Science.gov (United States)

    Truesdell, A.H.; Manon, M.A.; Jimenez, S.M.E.; Sanchez, A.A.; Fausto, L.J.J.

    1979-01-01

    Some wells of the Cerro Prieto geothermal field have undergone changes in the chemistry of fluids produced which reflect reservoir processes. Pressure decreases due to production in the southeastern part of the field have produced both drawdown of lower chloride fluids from an overlying aquifer and boiling in the aquifer with excess steam reaching the wells. These reservoir changes are indicated by changes in fluid chloride concentrations, Na/K ratios and measured enthalpies and by comparisons of aquifer fluid temperatures and chloride concentrations calculated from enthalpy and chemical measurements. Fluid temperatures have not been greatly affected by this drawdown because heat contained in the rock was transferred to the fluid. When this heat is exhausted, fluid temperatures may drop rapidly. ?? 1979.

  19. The origin of the Cerro Prieto geothermal brine

    Science.gov (United States)

    Truesdell, A.H.; Thompson, J.M.; Coplen, T.B.; Nehring, N.L.; Janik, C.J.

    1981-01-01

    The Cerro Prieto geothermal brine may have originated from mixing of Colorado River water with seawater evaporated to about six times its normal salinity. This mixture circulated deeply and was heated by magmatic processes. During deep circulation, Li, K, Ca, B, SiO2 and rare alkalis were transferred from rock minerals to the water, and Mg, SO4, and a minor quantity of Na were transferred to the rock. Similar alteration of seawater salt chemistry has been observed in coastal geothermal systems and produced in laboratory experiments. After heating and alteration the brine was further diluted to its present range of composition. Oxygen isotopes in the fluid are in equilibrium with reservoir calcite and have been affected by exploitation-induced boiling and dilution. ?? 1981.

  20. Reservoir engineering studies of the Cerro Prieto geothermal field

    Science.gov (United States)

    Goyal, K. P.; Lippmann, M. J.; Tsang, C. F.

    1982-09-01

    Reservoir engineering studies of the Cerro Prieto geothermal field began in 1978 under a five-year cooperative agreement between the US Department of Energy and the Comision Federal de Electricidad de Mexico, with the ultimate objective of simulating the reservoir to forecast its production capacity, energy longevity, and recharge capability under various production and injection scenarios. During the fiscal year 1981, attempts were made to collect information on the evolution history of the field since exploitation began; the information is to be used later to validate the reservoir model. To this end, wellhead production data were analyzed for heat and mass flow and also for changes in reservoir pressures, temperatures, and saturations for the period from March 1973 to November 1980.

  1. Geothermal emissions data base: Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, S.R. (comp.)

    1978-04-01

    A new database subset on the gaseous emissions from the Cerro Prieto geothermal field is presented. Properties and states of the reservoir fluid such as flow rates, wellhead pressure, and enthalpy are included in the file along with the well name and constituent measurement. This subset is the result of an initial screening of the data covering 1967 to 1969, and new additions will be appended periodically to the file. The data are accessed by a database management system as are all other subsets in the file. Thereby, one may search the database for specific data requirements and print selective output. For example, one may wish to locate reservoir conditions for cases only when the level of the constituent exceeded a designated value. Data output is available in the form of numerical compilations such as the attached, or graphical displays disposed to paper, film, or magnetic tape.

  2. Deforestación y actividades productivas en los valles del oeste de La Rioja y Catamarca : desde mediados del siglo XIX hasta la actualidad

    OpenAIRE

    Rojas, Facundo; Prieto, María del Rosario; Villagra, Pablo; Álvarez, Juan

    2014-01-01

    Se describe y explica el proceso de deforestación del área ocupada por los bosques de algarrobo en el oeste de La Rioja y Catamarca, a partir de mediados de siglo XIX hasta la actualidad. Este proceso estuvo asociado al desmonte del bosque nativo y a los cambios de uso del suelo originados por diferentes y sucesivos procesos socio– económicos, que tuvieron como actividades emergentes la minería, el ferrocarril y la demanda de product...

  3. Diagnóstico socio-ambiental para un desarrollo sustentable de la Puna Meridional Argentina, Localidad de Antofagasta de la Sierra, Catamarca

    Directory of Open Access Journals (Sweden)

    Liliana M. Manzi

    2008-05-01

    Full Text Available Se presenta un diagnóstico socio-ambiental realizado en la comunidad de Antofagasta de la Sierra, Provincia de Catamarca, Argentina, siendo tomados en consideración las unidades sociales de producción, los rebaños, las pasturas disponibles y los patrones de uso y tenencia de la tierra. Se pretende identificar y evaluar la incidencia del actual uso del espacio sobre el medio natural y discutir las iniciativas oficiales de desarrollo económico para este sector de la Puna argentina.

  4. LA MATERIALIDAD DE LA HISTORIA: EL CASO DE LA CONSTRUCCIóN DEL CAMINO POR VILLAVIL A TUCUMAN EN EL SIGLO XIX (DEPARTAMENTO ANDALGALÁ, CATAMARCA

    Directory of Open Access Journals (Sweden)

    Norma Ratto

    2009-12-01

    Full Text Available Within the elaboration of the study of Archeological Impact of the detour of Villavil’s mineral pipeline of Minera Alumbrera Ltd. (Departamento Andalgalá, Catamarca, different type of architectural evidence was documented and registered. Gathering orally transmitted information from local inhabitants of Villavil and also from the analysis of historical sources regarding road construction, it is interpreted that material remains belong to a road built in the XIXth Century, to achieve communication between the cities of Andalgalá and Tucumán. The construction work was interrupted by a catastrophic flood of Villavil River, destroying mostly of the road and causing its relocation.

  5. Results from two years of resistivity monitoring at Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Wilt, M.J.; Goldstein, N.E.

    1981-01-01

    Dipole-dipole resistivity measurements for the combined purposes of reservoir delineation and resistivity monitoring were first made at Cerro Prieto in 1978 and have continued on an annual basis since then. Two 20 km long dipole-dipole lines with permanently emplaced electrodes at one kilometer spacings were established over the field area; one of these lines is remeasured annually. Resistivity measurements are taken using a 25 kW generator capable of up to 80A output and a microprocessor controlled signal averaging receiver; this high power-low noise system is capable of highly accurate measurements even at large transmitter-receiver separations. Standard error calculations for collected data indicate errors less than 5% for all points, but 95% confidence intervals show error limits about 2 to 4 times higher. Analysis of collected data indicate little change in the apparent resistivity of the upper 300 m over the field production zone and that in this section measurements are relatively insensitive to the annual rainfall cycle. Apparent resistivity increases were observed over the older producing zone at Cerro Prieto at depths of 1 km and greater. Large zones of decreasing apparent resistivity were observed flanking the zone of increases on both sides. The increase in apparent resistivity in the production region may be due to an increasing fraction of steam in the reservoir resulting from a production related decline in reservoir pressure. Alternatively the increases may be the result of fresh water influx from the Colorado River. The zone of declining resistivity flanking the area of increase may be due to the movement of saline waters into the reservoir region as a result of the pressure decline. Quantitative modeling of observed changes is impractical owing to the high uncertainty in estimating apparent resistivity changes and the nonuniqueness of models.

  6. El urbanismo Inka y su vinculación con mesoclimas en el sitio "El Shincal de Quimivil" (Provincia de Catamarca, Argentina Inka urbanism associated with mesoclimatic conditions at the site "El Shincal de Quimivil" (Catamarca province, Argentina

    Directory of Open Access Journals (Sweden)

    Aylen Capparelli

    2006-12-01

    Full Text Available Los Inkas gestionaron el ambiente, de las distintas regiones que ocuparon, sobre la base tanto de sus conocimientos astronómicos -solares y lunares- como de aquellos referidos a la ecología y calendario agrícola -del maíz en especialde cada región. La producción excedente de una población se redistribuía luego en base a un sistema de almacenaje propio de este Estado. Dentro de este marco, se propone que el conocimiento de la diversidad de hábitats, y de los factores ecológicos a ellos asociados, les sirvió a los Inkas para planificar y garantizar el buen funcionamiento de cada unidad arquitectónica en cada centro administrativo. Por lo tanto, el objetivo principal de este trabajo es determinar si existe alguna vinculación entre las distintas condiciones mesoclimáticas que se encuentran en el lugar de implantación del sitio Inka El Shincal de Quimivil (Catamarca, Argentina y la distribución espacial de tres sectores arquitectónicofuncionales diferentes (almacenaje, habitacional, cultivo y un testigo (plaza. Se analizaron en forma univariada y multivariada 6 variables climáticas. Por sus altos valores de déficit de saturación de vapor del aire (DS, capacidad evaporante del aire y temperatura del suelo, el sector de almacenaje resultó el sector más propicio para lograr el secado y la preservación de los granos. El sector habitacional, mostró bajos DS y capacidad evaporante en primavera y verano, lo que contribuyó a condiciones más confortables bajo las elevadas temperaturas de esas estaciones. El sector cultivos, tuvo baja capacidad evaporante durante días con Zonda, y su mesoclima generalmente moderado, es el que más se ajusta a los requerimientos agroecológicos del maíz.The Inkas managed the environment of the different regions they occupied based on their astronomical and agroecological knowledge, especially in relation to maize. Surplus production was redistributed through a well developed storage system. Within

  7. EFFECTS OF LOCALIZED AQUIFER BOILING ON FLUID PRODUCTION AT CERRO PRIETO.

    Science.gov (United States)

    Truesdell, Alfred H.; D'Amore, Franco; Nieva, David

    1984-01-01

    Localized aquifer boiling in the shallow two-phase reservoir of Cerro Prieto has produced excess steam and increased electrical output. Unfortunately it has also caused near-well mineral deposition that has decreased permeability and fluid flow. Inflow of cold water has limited the extent of aquifer boiling and permeability loss. The deeper reservoir at Cerro Prieto may need injection of cold water to decrease boiling and prevent loss of production. Refs.

  8. Geochemistry of igneous rocks from the Cerro Prieto geothermal field, northern Baja California, Mexico

    Science.gov (United States)

    Herzig, C. T.

    1990-08-01

    Fractional crystallization of basaltic magma, derived from an oceanic affinity source region present beneath the Salton Trough and emplaced into a pull-apart basin of this continental rift regime, produced a tholeiitic suite of hypabyssal rocks consisting of basalt, andesite and dacite within the Cerro Prieto geothermal field, located in northern Baja California, Mexico. Higher light-rare-earth-element abundances for a basalt from the Cerro Prieto geothermal field in comparison to basalts from the Gulf of California and the East Pacific Rise suggest partial assimilation of crustal materials into the parental magmas generated beneath the Salton Trough. The crustal contaminant may be present near the surface today in the form of granitoids of the Peninsular Ranges batholith, at deeper levels as hydrothermally altered materials near the base of the Salton Trough, or may be a relict feature of Tertiary subduction contained within the upper mantle beneath the Salton Trough. The Sr isotopic compositions of dacites from the nearby Cerro Prieto volcano range from 0.7029 to 0.7036, indicating an oceanic affinity source for these rocks. The suite of hypabyssal rocks of tholeiitic affinity present within the Cerro Prieto geothermal field, related by fractional crystallization, link the dacite volcano of Cerro Prieto to gabbroic plutons inferred to exist beneath the Cerro Prieto geothermal field.

  9. Parasitosis intestinales en relación con la cultura higiénica de poblaciones rurales de Catamarca.

    Directory of Open Access Journals (Sweden)

    Monferrán, M. C.

    2003-01-01

    Full Text Available Los estudios realizados sobre prevalencia de parasitosis intestinales humanas en comunidades urbanas y rurales en la provincia de Catamarca, revela altos índices. Las causas son múltiples, entre las que se encuentran factores ecológicos y sociales. Las condiciones climáticas imperantes en una zona geográfica resultaran favorables o no a la presentación de algunas parasitosis como por ejemplo las geohelmintiasis.Se atribuye igual importancia a la educación, vivienda, alimentación, recursos económicos, falta de higiene, contaminación ambiental, etc.. Se realizan estudios de prevalencia de parasitosis intestinales en pobladores de dos regiones climáticamente diferentes de nuestra provincia como son los Dptos. La Paz y Paclín detectándose en algunas comunidades índices altos de hasta el 81 %.También se ha notado la influencia climática regional sobre la distribución de las parasitosis intestinales .En La Paz, existe un predominio de las protozoosis y en Paclín las geohelmintiasis son frecuentes y diversas. Las parasitosis detectadas estarían relacionadas en un alto grado a la denominada cultura higiénica, pues las prácticas de la higiene individual y familiar, la deposición de sus excretas, la convivencia con animales domésticos, el manejo de sus rebaños, son costumbres regionales que se han transmitido por generaciones e influyen notablemente en la difusión y la conservación de estos altos índices de parasitosis intestinales en detrimento de la salud de los habitantes.

  10. Evidence of recent deep magmatic activity at Cerro Bravo-Cerro Machín volcanic complex, central Colombia. Implications for future volcanic activity at Nevado del Ruiz, Cerro Machín and other volcanoes

    Science.gov (United States)

    Londono, John Makario

    2016-09-01

    In the last nine years (2007-2015), the Cerro Bravo-Cerro Machín volcanic complex (CBCMVC), located in central Colombia, has experienced many changes in volcanic activity. In particular at Nevado del Ruiz volcano (NRV), Cerro Machin volcano (CMV) and Cerro Bravo (CBV) volcano. The recent activity of NRV, as well as increasing seismic activity at other volcanic centers of the CBCMVC, were preceded by notable changes in various geophysical and geochemical parameters, that suggests renewed magmatic activity is occurring at the volcanic complex. The onset of this activity started with seismicity located west of the volcanic complex, followed by seismicity at CBV and CMV. Later in 2010, strong seismicity was observed at NRV, with two small eruptions in 2012. After that, seismicity has been observed intermittently at other volcanic centers such as Santa Isabel, Cerro España, Paramillo de Santa Rosa, Quindío and Tolima volcanoes, which persists until today. Local deformation was observed from 2007 at NRV, followed by possible regional deformation at various volcanic centers between 2011 and 2013. In 2008, an increase in CO2 and Radon in soil was observed at CBV, followed by a change in helium isotopes at CMV between 2009 and 2011. Moreover, SO2 showed an increase from 2010 at NRV, with values remaining high until the present. These observations suggest that renewed magmatic activity is currently occurring at CBCMVC. NRV shows changes in its activity that may be related to this new magmatic activity. NRV is currently exhibiting the most activity of any volcano in the CBCMVC, which may be due to it being the only open volcanic system at this time. This suggests that over the coming years, there is a high probability of new unrest or an increase in volcanic activity of other volcanoes of the CBCMVC.

  11. Hydrogeophysics and Water Balance of Cerro Prieto Dam, NE Mexico

    Science.gov (United States)

    Yutsis, V.; de León Gómez, H.; Masuch Oesterreich, D.; Izaguirre, F.

    2007-05-01

    The geographical location of the State of Nuevo Leon, due to its physiographic features, has temperate and arid climate; undeveloped drainage, low precipitations, and high evapotranspiration rates, as well as rapid demographic growth. The hydrological data of the Pablillo basin, registered in the hydrometric station Cerro Prieto, showed an annual precipitation from 415 up to 1130 mm/a , the mean evaporation of 705 mm/a (up to 2460 mm/a in 1996). The maximum water storage of the Cerro Prieto reservoir is 395 millions m3 which corresponds to a water level of 295 meters. However, this level was reached only three times after the dam's construction. By the end of June 2006 the water level was at 276.2 m which corresponds to a water volume of about 127,806,300 m3 which is less than a third of maximum storage. Analysis of hydrological data showed sufficient misbalance between water recharge (by rain, river flow) and loss due to evaporation, filtration, extraction, discharge, etc. 160 gravity reading points, 400 onshore magnetic field readings as well as about 250 offshore magnetic points were carried out. The standard corrections as instrumental drift, latitude, elevation, IGRF, etc. were applied to obtained data. Data procession includes Fourier transformation, wavelength filters, upward continuation, vertical and horizontal derivates, etc. As a result a 2D geological-geophysical models and 3D maps were elaborated. The general trend of the magnetic field reduced to a pole is NW - SE on which background anomalies of northeast trend are obviously traced. The general trend of the gravity field received as a result of our works is the same. However, local magnetic and residual gravity anomalies have mosaic character and, being morphologically extended in a NE direction, grouped in chains of northwest trend. Potential data interpretation allows assuming a series of the superficial fractures focused in a NE direction, perpendicular (NW-SE) to the general deep fault. The

  12. Investigating the subsurface connection beneath Cerro Negro volcano and the El Hoyo Complex, Nicaragua

    Science.gov (United States)

    Venugopal, Swetha; Moune, Séverine; Williams-Jones, Glyn

    2016-10-01

    Cerro Negro, the youngest volcano along the Central American Volcanic Belt (CAVB), is a polygenetic cinder cone with relatively frequent basaltic eruptions. The neighbouring El Hoyo complex, of which Las Pilas is the dominant edifice, is a much larger and older complex with milder and less frequent eruptions. Previous studies have suggested a deep link beneath these two closely spaced volcanoes (McKnight, 1995; MacQueen, 2013). Melt inclusions were collected from various tephra samples in order to determine whether a connection exists and to delineate the features of this link. Major, volatile, and trace elemental compositions reveal a distinct geochemical continuum with Cerro Negro defining the primitive endmember and El Hoyo representing the evolved endmember. Magmatic conditions at the time of melt inclusion entrapment were estimated with major and volatile contents: 2.4 kbar and 1170 °C for Cerro Negro melts and 1.3 kbar and 1130 °C for El Hoyo melts with an overall oxygen fugacity at the NNO buffer. Trace element contents are distinct and suggest Cerro Negro magmas fractionally crystallise while El Hoyo magmas are a mix between primitive Cerro Negro melts and residual and evolved El Hoyo magma. Modelling of end member compositions with alphaMELTS confirms the unique nature of El Hoyo magmas as resulting from incremental mixing between Cerro Negro and residual evolved magma at 4 km depth. Combining all available literature data, this study presents a model of the interconnected subsurface plumbing system. This model considers the modern day analogue of the Lemptégy cinder cones in Massif Central, France and incorporates structurally controlled dykes. The main implications of this study are the classification of Cerro Negro as the newest conduit within the El Hoyo Complex as well as the potential re-activation of the El Hoyo edifice.

  13. Detailed microearthquake studies at the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Majer, E.L. (Lawrence Berkeley Lab., CA); McEvilly, T.V.

    1981-01-01

    There appears to be an increase in seismic activity within the Cerro Prieto production zone since early 1978. The microearthquake activity is now more or less constant at a rate of 2 to 3 events per day. The b-values within the field are significantly higher inside the production zone than are those for events on faults outside of the production region. The earthquakes seem to be controlled by the Hidalgo fault, although slight clustering was observed in the center of the main production region. The earthquakes within the production zone may reflect the reservoir dynamics associated with heat and mass withdrawal. Mechanisms such as volume change, thermal stresses and weakening of materials associated with boiling (i.e., phase changes, dissolution) may all be responsible for the increased seismic activity. Although a small reinjection program has started, the pressure drawdown conditions existing within the field would imply that increased pore pressure resulting from the injection activities is not responsible for the increased seismic activity.

  14. Evolution of the Cerro Prieto reservoirs under exploitation

    Energy Technology Data Exchange (ETDEWEB)

    Truesdell, A.H.; Lippmann, M.J. [Lawrence Berkeley National Lab., CA (United States); Puente, H.G. [Comision Federal de Electricidad, Mexicali (Mexico)

    1997-07-01

    The Cerro Prieto Geothermal field of Baja California (Mexico) has been under commercial production to generate electricity since 1973. Over the years, the large amount of Geothermal fluids extracted (at present about 12,000 tons per hour) to supply steam to the power plants has resulted in a reduction of pressures, changes in reservoir processes, and increased flow of cooler groundwater into the geothermal system. The groundwater recharging the reservoir moves horizontally through permeable layers, as well as vertically through permeable fault zones. In addition, the supply of deep hot waters has continued unabated, and perhaps has increased as reservoir pressure decreased. Since 1989, this natural fluid recharge has been supplemented by injection which presently amounts to about 20% of the fluid produced. Changes in the chemical and physical characteristics of the reservoir fluids due to the drop in pressures and the inflow of cooler groundwaters and injectate have been detected on the basis of wellhead data. These changes point to reservoir processes like local boiling, phase segregation, steam condensation, mixing and dilution. Finally, the study identified areas where fluids are entering the reservoir, as well as indicated their source (i.e. natural Groundwater recharge versus injectate) and established the controlling geologic structures.

  15. Cerro Prieto cold water injection: effects on nearby production wells

    Energy Technology Data Exchange (ETDEWEB)

    Truesdell, A.H.; Lippmann, M.J.; De Leon, J.; Rodriguez, M.H.

    1999-07-01

    The liquid-dominated Cerro Prieto geothermal field of northern Baja California, Mexico has been under commercial exploitation since 1973. During the early years of operation, all waste brines were sent to an evaporation pond built west of the production area. In 1989, cooled pond brines began to be successfully injected into the reservoir along the western boundary of the geothermal system. The injection rate varied over the years, and is at present about 20% of the total fluid extracted. As expected under the continental desert conditions prevailing in the area, the temperature and salinity of the pond brines change with the seasons, being higher during the summer and lower during the winter. The chemistry of pond brines is also affected by precipitation of silica, oxidation of H{sub 2}S and reaction with airborne clays. Several production wells in the western part of the field (CP-I area) showed beneficial effects from injection. The chemical (chloride, isotopic) and physical (enthalpy, flow rate) changes observed in producers close to the injectors are reviewed. Some wells showed steam flow increases, in others steam flow decline rates flattened. Because of their higher density, injected brines migrated downward in the reservoir and showed up in deep wells.

  16. What lies beneath the Cerro Prieto geothermal field?

    Energy Technology Data Exchange (ETDEWEB)

    Elders, W.A.; Williams, A.E.; Biehler, S. [Univ. of California, Riverside, CA (United States)

    1997-12-31

    Although the Cerro Prieto geothermal reservoir is one of the world`s largest geothermal developments, conflicting ideas persist about the basement beneath it. The current plan to drill a 6 km deep exploratory well in the eastern part of the field has brought this controversy into sharper focus. This paper discusses criteria which any model of what lies beneath the reservoir must meet, in terms of regional tectonics and geophysics, of the metamorphic and igneous rocks thus far encountered in drilling, and of models of possible heat sources and coupling between the hydrothermal and magmatic systems. Our analysis confirms the interpretation that the crystalline basement beneath the sediments, rather than being granitic, is oceanic in character, resembling an ophiolite complex. The heat source is most likely a cooling gabbroic intrusion, several kilometers in diameter, overlain by a sheeted dike swarm. A 6 km deep bore-hole centered over such an intrusion would not only be one of the world`s deepest geothermal wells but could also be one of the hottest.

  17. Performance of casings in Cerro Prieto production wells

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez A, B.; Vital B, F.; Bermejo M, F.; Sanchez G, G.

    1981-01-01

    A careful evaluation of different production casings used at Cerro Prieto from 1964 to date has shown that the following casings have yielded particularly impressive results: 7 5/8-in. diameter, J-55, 26 lb/ft; 7 5/8-in. diameter, K-55, 45.3 lb/ft; and 5-in. diameter, K-55, 23.2 lb/ft. These casings differ from others of the same diameter but lighter weight which were also used at the field. The results are favorable in spite of severe construction problems, especially the loss of circulation during cementing operations, which we encountered in some of the wells where these casings were used. The use of gravity-fed fine sand as packing material and the arrangement of the production and intermediate casings were important in avoiding damage due to tension-compression stresses and, above all, damage due to internal or external corrosion over time. This situation is clearly evidenced if we compare the damage to the above casings with that experienced by grade N-80 production casings, especially in a corrosive environment.

  18. Update of the conceptual geological model for the geothermal reservoir in Cerro Prieto, BC; Actualizacion del modelo geologico conceptual del yacimiento geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Lira Herrera, Hector [Comision Federal de Electricidad, Mexicali, B.C., (Mexico)

    2005-06-01

    An updated, conceptual geologic model is presented for the geothermal reservoir in Cerro Prieto geothermal field. The tectonic extension that formed the Basin and Range Province of the Western United States and Northwestern Mexico during Upper Tertiary in the Cerro Prieto area resulted in the formation of a half graben tectonic basin between the Cerro Prieto and Imperial faults. Called the Cerro Prieto basin, it includes listric faults, predominately northwest-southwest trending, stepped generally to the northeast. The zone of cortical weakness, formed during the Tertiary, allowed an intrusion of basic rock associated with the magnetic anomaly know as Nuevo Leon. The intrusive rock has been fed by new magmatic intrusions originated by the present tectonic extension of the Gulf of California. The oldest rocks identified in the area are gneiss and biotite-schists of Permian-Jurassic age and tonalities of Jurassic-Cretaceous age in contact with Cretaceous granites, all representing the regional basement. The lithologic column in the subsurface of the Cerro Prieto basin in formed by a basement of Cretaceous granites; an argillaceous package resting on the basement composed of gray shales with interleaves of sandstone, Tertiary brown-shales and mudstone, with an average thickness of 2700 m; clastic sediments of the Quaternary age deposited mainly by the Colorado River and alluvial fans of the Cucapa Range, comprised of gravel, sands and clays with an average thickness of 2500 m, covering the shales. The fluids feeding the geothermal reservoir heat as they pass though the zone where the basic intrusive is located (the heat source) and migrate through the listric faults toward the permeable layers of sandstone located within the gray shales. [Spanish] Se presenta el modelo geologico conceptual actualizado del yacimiento geotermico de Cerro Prieto. La tectonica extensional que origino la Provincia de Cuencas y Cordilleras (Basin and Range) del oeste de Estados Unidos y

  19. IDENTIFICACIÓN INTERESPECÍFICA DE CAMÉLIDOS EN EL VALLE DE AMBATO (CATAMARCA, ARGENTINA). UNA APROXIMACIÓN A LA PROBLEMÁTICA DESDE DISTINTAS LÍNEAS DE ANÁLISIS/Interspecific identification of camelids in Ambato valley (Catamarca, Argentina)...

    OpenAIRE

    2012-01-01

    La identificación interespecífica de camélidos y la distinción entre morfotipos de llamas en los materiales óseos recuperados en sitios arqueológicos constituyen dos aspectos de suma importancia dentro de los estudios zooarqueológicos del noroeste argentino y de la región andina en general. En este trabajo se pretende contribuir a esta problemática, mediante el entrecruzamiento de distintas líneas de análisis aplicadas sobre los restos de camélidos procedentes del Valle de Ambato, Catamarca, ...

  20. Petrological and Geochemical Studies of the Igneous Rocks at Cerro EL Borrego, Chihuahua, Mexico

    Science.gov (United States)

    Estrada, V. M.; Espejel-Garcia, V. V.; Villalobos-Aragon, A.

    2013-05-01

    Cerro El Borrego, which is a hill composed of igneous rocks, is located 13.7 km to the SW of Chihuahua city, in northern Mexico. The coordinates of the hill are 28° 11' 07'' N latitude and 105° 33' 23'' W longitude. The study area is within the Basin and Range Physiographic Province, characterized by a complex tectonic-structural pattern, such as elongated ranges with folds and igneous rock formations of Paleogene age. A lava flow of Oligocene age is part of the large volcanic and plutonic activity at the early times of the Cenozoic, which occurred to the NW portion of Mexico. In Cerro El Borrego, the rocks that outcrop are middle Oligocene's rhyolitic tuff to the NW of the hill, while to its SE there is a Pleistocene polymictic conglomerate. Previous work shows different interpretations about the origin and composition of the igneous rocks at Cerro El Borrego. This project includes whole rock and textural analyses, which helped to discern the petrogenesis of these rocks. Preliminary petrographic analyses indicate that the Cerro El Borrego, is a structural dome, and its feldspar-rich rocks contain large crystals that can be appreciated without a microscope. The presence of a porphyritic texture, suggest a sallow intrusion origin. A preliminary conclusion is that Cerro El Borrego is a shallow depth intrusive body with a syenitic composition derived from the Oligocene plutonic activity.

  1. Crecimiento y nutrición de la población infanto-adolescente de Azampay (Catamarca

    Directory of Open Access Journals (Sweden)

    Padula, Gisel

    2004-01-01

    Full Text Available A partir de 1995 se constituyó un grupo multidisciplinario, que desarrolló sus investigaciones en la localidad de Azampay (Catamarca, abordando el estudio integral de la problemática bio-socio-cultural de las comunidades actuales y arqueológicas con el objetivo de caracterizar procesos de largo plazo. La elección de la localidad de Azampay se realizó en función de su claro rol estratégico a nivel arqueológico, como proveedor de alimentos durante el Período de Desarrollos Regionales, así como por el tamaño reducido de la población actual y su localización fuera de las rutas de comunicación habituales, que la convierten en óptima para realizar estudios sobre población total, minimizando el sesgo que un muestreo provoca. El objetivo es realizar una selección de aquellos trabajos desarrollados en relación al Crecimiento y Nutrición de la población infanto-adolescente de Azampay y sus alrededores. Se realizó la evaluación nutricional a través del establecimiento de los indicadores P//E, T//E y P//T, se estudió el dimorfismo sexual a partir de la morfometría craneofacial y se caracterizó la salud bucal y dieta, con la obtención del Perfil Patológico Dental de cada individuo. Así, la población infanto-adolescente presenta: 1.- Un alto porcentaje de individuos distróficos, siendo en su mayor parte niños emaciados; 2.- Ausencia de diferencias craneofaciales significativas entre ambos sexos, indicando un fuerte estrés nutricional y 3.- Altas frecuencias de fluorosis y gingivitis y frecuencias medias a bajas de periodontitis y caries, evidenciando una disminución en el componente agrícola, junto con deficiencias vitamínicas y falta de higiene dental.

  2. Measured ground-surface movements, Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Massey, B.L.

    1981-01-01

    The Cerro Prieto geothermal area in the Mexicali Valley, 30 kilometers southeast of Mexicali, Baja California, incurred slight deformation because of the extraction of hot water and steam, and probably, active tectonism. During 1977 to 1978, the US Geological Survey established and measured two networks of horizontal control in an effort to define both types of movement. These networks consisted of: (1) a regional trilateration net brought into the mountain ranges west of the geothermal area from stations on an existing US Geological Survey crustal-strain network north of the international border; and (2) a local net tied to stations in the regional net and encompassing the present and planned geothermal production area. Electronic distance measuring instruments were used to measure the distances between stations in both networks in 1978, 1979 and 1981. Lines in the regional net averaged 25 km. in length and the standard deviation of an individual measurement is estimated to be approx. 0.3 part per million of line length. The local network was measured using different instrumentation and techniques. The average line length was about 5 km. and the standard deviation of an individual measurement approached 3 parts per million per line length. Ground-surface movements in the regional net, as measured by both the 1979 and 1981 resurveys, were small and did not exceed the noise level. The 1979 resurvey of the local net showed an apparent movement of 2 to 3 centimeters inward toward the center of the production area. This apparent movement was restricted to the general limits of the production area. The 1981 resurvey of the local net did not show increased movement attributable to fluid extraction.

  3. Interaction of cold-water aquifers with exploited reservoirs of the Cerro Prieto geothermal system

    Science.gov (United States)

    Truesdell, Alfred; Lippmann, Marcelo

    1990-01-01

    Cerro Prieto geothermal reservoirs tend to exhibit good hydraulic communication with adjacent cool groundwater aquifers. Under natural state conditions the hot fluids mix with the surrounding colder waters along the margins of the geothermal system, or discharge to shallow levels by flowing up fault L. In response to exploitation reservoir pressures decrease, leading to changes in the fluid flow pattern in the system and to groundwater influx. The various Cerro Prieto reservoirs have responded differently to production, showing localized near-well or generalized boiling, depending on their access to cool-water recharge. Significant cooling by dilution with groundwater has only been observed in wells located near the edges of the field. In general, entry of cool water at Cerro Prieto is beneficial because it tends to maintain reservoir pressures, restrict boiling, and lengthen the life and productivity of wells.

  4. SELF-POTENTIAL SURVEY AT THE CERRO PRIETO GEOTHERMAL FIELD, BAJA CALIFORNIA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Corwin, R.F.; Diaz C., S.; Rodriguez B., J.

    1978-06-01

    In December 1977, two self-potential survey lines were run across the producing area of the Cerro Prieto geothermal field, located about 30 km south of Mexicali, Baja California, Mexico. The purpose of the survey was to determine whether significant self-potential variations were related to the known geothermal activity. Large-amplitude, long-wavelength self-potential anomalies are seen in the Cerro Prieto geothermal field. The inflection points of the anomalies are roughly centered over two major faults thought to act as conduits for the thermal fluids, and the form of the anomalies indicates that they may be generated by electrical activity extending to a depth of several km along the fault zones. Thus, self-potential measurements may be helpful in tracing thermally active fault zones in the Cerro Prieto area.

  5. La estructura caldérica Vis Vis asociada al volcanismo mioceno del distrito minero Farallón Negro, provincia de Catamarca

    Directory of Open Access Journals (Sweden)

    M.B. Palacio

    2005-09-01

    Full Text Available Sobre la base de la interpretación geológica de datos aeromagnéticos de alta resolución, combinados con estudios petrográficos, se identificó una estructura caldérica en la depresión de Vis Vis, provincia de Catamarca, que forma parte del evento volcánico mioceno del distrito Farallón Negro. Se definieron dos tipos litológicos, andesitas y tobas, como así también dos eventos de alteración hidrotermal, propilítica y arcilloso-sericítica, que afectan a las rocas de este centro eruptivo.

  6. Arqueología y etnohistoria: la construcción de un problema de investigación (Abaucán, Tinogasta, Catamarca

    Directory of Open Access Journals (Sweden)

    Norma Ratto

    2012-12-01

    Full Text Available Se trata de un trabajo interdisciplinario que articula información, interrogantes y resultados de la arqueología y la etnohistoria acerca de los pueblos nativos del sector norte de la cuenca del Abaucán en el oeste tinogasteño (Catamarca. La re-lectura de la información existente de ambos campos disciplinarios fue integrada con nuevas evidencias que consisten en: una fuente documental inédita de los comienzos del siglo XVII y nuevos contextos arqueológicos y ecológicos que dan cuenta de procesos de inestabilidad ambiental de alcance regional. Nuestro objetivo general es problematizar sobre la conformación del espacio social, tanto en momentos de la conquista incaica como española, como así también discutir el impacto que tuvieron una y otra sobre las poblaciones locales del oeste tinogasteño. Asimismo, discutimos la localización geográfica de los principales asentamientos prehispánicos que tuvieron continuidad histórica hasta el período colonial.This interdisciplinay paper combines archaeological and ethnohistorical information with questions and results about the native people located in the north sector of the Abaucan basin, west of Tinogasta area -Catamarca province. The information provided by both disciplines was reread and new evidence, consisting of an unpublished documentary source of early seventeenth century and new archaeological and ecological contexts reflecting processes of regional environmental instability, was integrated. Problematizing the construction of social space during the Inca and Spanish conquests is our general objective; we also discuss about the impact of both conquering events upon the population located west of Tinogasta. Additionally we argue about the geographical location of the main prehispanic settlements with continuity in colonial times

  7. Gas equilibria in Cerro Prieto geothermal field, B.C., Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Portugal, E.; Barragan, R.M.; Izquierdo, G. [Inst. de Investigaciones Electricas, Morelos (Mexico); Leon, J. de [Comision Federal de Electricidad, Mexicali B.C. (Mexico)

    2003-07-01

    Gas equlibria methods involving fischer-tropsch-pyrite-magnetite; and fischer-tropsch-pyrite-hematite-pyrite-magnetite reactions were used to evaluate reservoir temperature and a mass steam fraction in Cerro Prieto geothermal field. These approaches have been applied in some selected producing wells from four areas under exploitation. The results show good correlation for both equilibria methods; however fischer-tropsch; pyrite-magnetite reactions provide the best estimation of the physical reservoir parameters. The main processes found for Cerro Prieto IV area are lateral vapor contribution and the inflow of hotter and deeper fluid with high liquid saturation. (orig.)

  8. Indios y blancos en la ciudad minera: Cerro de Pasco en el siglo XIX1

    OpenAIRE

    Contreras, Carlos

    2014-01-01

    En este artículo se presenta una descripción de las condiciones de vida, materiales y culturales en Cerro de Pasco durante el siglo pasado, cuando era una de las principales ciudades de la sierra peruana, tanto en lo económico como en lo demográfico.El autor discute las características de la estructura social de Cerro de Pasco, recalcando la yuxtaposición de elementos económicos y étnico-culturales y el tipo de relaciones sociales prevalecientes. Luego describe las características y condicion...

  9. Santuarios prehispánicos identificados sobre cimas de cerros en Aguascalientes, México

    OpenAIRE

    Macías Quintero, Juan Ignacio; Villagrana Prieto, Citlallitl Selene

    2016-01-01

    Este trabajo considera la presencia de estructuras arqueológicas dispuestas sobre la cima de cerros en la región Centro-Norte de México, con énfasis en el valle del río Verde-San Pedro, Aguascalientes. Regularmente, los sitios dispuestos en cerros aislados y cimas escarpadas se han contemplado como fortificaciones que reflejaban conflictos e inestabilidad. Sin embargo, hemos identificado que estos asentamientos podrían ser de santuarios que, junto con otros elementos naturales y culturales (p...

  10. ACERCA DEL USO DE PULIDORES O LITOS NO MODIFICADOS EN LA PRODUCCIÓN CERÁMICA DEL SITIO VILLAVIL (PROVINCIA DE CATAMARCA, ARGENTINA (On the Use of Unmodified Lithic Polishers in the Ceramic Production of the Villavil Site (Province of Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    Julieta Lynch

    2015-09-01

    Full Text Available El siguiente trabajo tiene como objetivo profundizar el conocimiento sobre las actividades que se desarrollaron en el sitio Villavil, localizado al norte del valle de Hualfín, provincia de Catamarca, Argentina. Se analizaron las características tecnomorfológicas y funcionales de los conjuntos cerámicos, como así también del material lítico asociado a la producción cerámica de uno de los recintos que conforman el sitio (Recinto Rectangular 1. Los resultados obtenidos han permitido profundizar acerca de las distintas etapas de producción cerámica y de los elementos líticos que habrían participado en su proceso de manufactura. ENGLISH: The main objective of this paper is to improve the knowledge of the ancient activities in the site of Villavil, located in the northern Hualfin Valley, Catamarca, Argentina. The techno-morphology, functional ceramic characteristics, and lithic material associated to ceramic production from one structure forming the archaeological site (Rectangular Structure 1 has been analyzed. These results have helped to better understand the different stages of ceramic production and the lithic elements that would have been part of the manufacturing process.

  11. ESTUDIOS PETROGRÁFICOS Y DE CORTES DELGADOS PARA LA IDENTIFICACIÓN DE MATERIAS PRIMAS LÍTICAS EN EL SECTOR NORTE DEL VALLE DE HUALFÍN (CATAMARCA, ARGENTINA (Petrographic and Thin Section Analysis for the Identification of Raw Lithic Materials in the Northern Area of the Hualfín Valley (Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    Julieta Lynch

    2016-06-01

    Full Text Available El objetivo del siguiente trabajo se centra en el análisis macroscópico y en estudios petrográficos microscópicos realizados sobre materiales líticos arqueológicos recuperados de los sitios Villavil y Villavil 2 (Hualfín, Catamarca, Argentina. Los resultados obtenidos permitieron identificar las materias primas utilizadas en la manufactura de artefactos asociados a ocupaciones del periodo de Desarrollos Regionales/Inka (ca. 900 al 1400 d. C. y, en base a la información geológica de la zona, se realizaron observaciones acerca de su posible procedencia. Esto permitió discutir las hipótesis planteadas con anterioridad acerca de las prácticas relacionadas con su aprovisionamiento. ENGLISH: The main objective of this study is the macroscopic and microscopic petrographic analysis of lithic materials recovered from the sites of Villavil and Villavil 2 (Hualfín, Catamarca, Argentina. The results obtained from this analysis allowed for the identification of the raw materials used in the manufacture of artifacts associated with Regional Developments/Inka Period (ca. 900 to 1400 A.D. occupations. Based on regional geological information, we are able to posit the source locations of these raw materials. This allows for a discussion of previous hypotheses regarding practices of lithic procurement in the area.

  12. The Cerro Grande Fire - From Wildlife Modeling Through the Fire Aftermath

    Energy Technology Data Exchange (ETDEWEB)

    Rudell, T. M. (Theresa M.); Gille, R. W. (Roland W.)

    2001-01-01

    The Cerro Grande Fire developed from a prescribed burn by the National Park Service at Bandelier National Monument near Los Alamos, New Mexico. When the burn went out of control and became a wildfire, it attracted worldwide attention because it threatened the birthplace of the atomic bomb, Los Alamos National Laboratory (LANL). Was LANL prepared for a fire? What lessons have been learned?

  13. Crecimiento y nutrición de la población infanto-adolescente de Azampay (Catamarca

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    Padula, Gisel

    2003-01-01

    Full Text Available A partir de 1995 se constituyó un grupo multidisciplinario, que desarrolló sus investigaciones en la localidad de Azampay (Catamarca, abordando el estudio integral de la problemática bio-socio-cultural de las comunidades actuales y arqueológicas con el objetivo de caracterizar procesos de largo plazo. La elección de la localidad de Azampay se realizó en función de su claro rol estratégico a nivel arqueológico, como proveedor de alimentos durante el Período de Desarrollos Regionales, así como por el tamaño reducido de la población actual (300 individuos y su localización fuera de las rutas de comunicación habituales, que la convierten en óptima para realizar estudios sobre población total, minimizando el sesgo que un muestreo provoca. Esta condición posibilita trabajar con mayor profundidad analítica proporcionando mejor comprensión sobre: ocupación del espacio; migración; organización familiar; propiedad de la tierra y el agua; crecimiento y desarrollo de la población infantil. Todos éstos, temas que pueden ser referidos y comparados con otras comunidades pertenecientes a la región. La siguiente presentación, tiene por objeto, realizar una selección de aquellos trabajos desarrollados en relación al Crecimiento y Nutrición de la población infanto-adolescente de Azampay y sus alrededores. Se realizó la evaluación nutricional a través del establecimiento de los indicadores P//E, T//E y P//T; se estudió el dimorfismo sexual a partir de la morfometría craneofacial; y se caracterizó la salud bucal y dieta, con la obtención del Perfil Patológico Dental de cada individuo. Así, la población infanto-adolescente de Azampay y sus alrededores, presenta: 1- Un alto porcentaje de individuos distróficos, siendo en su mayor parte niños emaciados, seguido por aquellos con desnutrición actual y luego los desmedrados; 2- Ausencia de diferencias craneofaciales significativas entre ambos sexos, indicando un fuerte estr

  14. LA ALFARERÍA DEL TARDÍO PREHISPÁNICO DEL VALLE DEL BOLSÓN (CATAMARCA, ARGENTINA: ¿PRODUCCIÓN LOCAL O ALÓCTONA? / The Late Prehispanic pottery of the Bolsón Valley (Catamarca, Argentine: local or allochthonous production?

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    Verónica Puente

    2014-11-01

    Full Text Available En este trabajo se presentan los resultados obtenidos en los estudios de procedencia de conjuntos cerámicos recuperados en dos asentamientos conglomerados del valle del Bolsón (Belén, Catamarca, Argentina vinculados a ocupaciones del tardío prehispánico (ca. 900-1600 DC. Las muestras estudiadas corresponden principalmente a cerámica pintada en negro sobre rojo reconocida como de estilo Belén, en menor medida ordinaria y excepcionalmente negro sobre crema y ante. Se complementaron análisis petrológicos y análisis por activación neutrónica instrumental realizados a la alfarería y a materias primas adecuadas para la producción alfarera muestreadas en la región. Se concluye que un grupo mayoritario de piezas fueron elaboradas con arcillas y arenas procedentes de la región bajo estudio. Asimismo, se destacan similitudes composicionales entre la vajilla recuperada en ambos asentamientos a pesar de las diferencias logísticas y estratégicas de emplazamiento. Los resultados generados son un importante aporte al tema de la producción alfarera a escala suprarregional dado que evidencian la coexistencia de distintos locus de producción cerámica en el oeste catamarqueño durante el lapso temporal estudiado.   Palabras clave: cerámica, tardío prehispánico, procedencia, análisis de activación neutrónica, petrografía.   Abstract The results obtained in the study of the provenance of ceramic recovered in two conglomerates settlements of the valley of El Bolsón (Belén, Catamarca, Argentina linked to prehispanic late occupations (ca. 900-1600 AD are given. The samples analyzed correspond mainly to Belén style ceramic, in lesser frequency to ordinary, and exceptionally to black over cream and beige. This study combined petrological and neutron instrumental activation analysis made in both kind of samples, archaeological pottery and local raw materials. It is concluded that a majority of archaeological pottery were made with clay and

  15. Modelos de aptitud espacial para la agricultura prehispánica y actual en el valle de Santa María, Catamarca, Argentina

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    Sonia Lanzelotti

    2015-12-01

    Full Text Available RESUMEN Se presentan modelos de aptitud para el desarrollo de la agricultura prehispánica y actual en un sector del valle de Santa María (Catamarca, Argentina, a través de la aplicación de técnicas de evaluación multicriterio con Sistemas de Información Geográfica. La base cartográfica fue conformada a partir de imágenes satelitales en combinación con mapas de elaboración acerca de unidades geomorfológicas, provincias fitogeográficas, hidrografía y áreas con evidencia arqueológica de agricultura prehispánica. Se observó que el área con mayor potencial para la agricultura se ubica en el sector pedemontano de la sierra del Aconquija, seguido por el fondo de valle. Este patrón coincide principalmente con el registro arqueológico prehispánico, pero no con la distribución espacial de las explotaciones agrícolas actuales. La relación entre la sociedad y la naturaleza, mediatizada a través de la tecnología, se presenta como la clave de interpretación. ABSTRACT This study was performed with the objective to identify suitable areas for development of pre-Hispanic and contemporary agriculture in Santa Maria Valley (Catamarca, Argentina through the application of multicriteria evaluation techniques using Geographic Information Systems. The base map was based on data obtained from satellite images in combination with thematic maps specially prepared about geomorphological units, phytogeographic provinces, hydrography and areas with archaeological evidence of prehispanic agriculture. It was observed that the area with the greatest potential for agriculture is located in the piedmont sector of the Aconquija mountain, followed by the bottom of the valley. This pattern coincides mainly with the pre-Hispanic archaeological record, but not with the spatial distribution of existing farms. The relationship between society and nature, mediated through technology, is presented as the key to interpretation

  16. Estudio de microrrestos silíceos en sistemas de aterrazamiento del primer milenio DC en el Valle de Ambato (Andes del sur, Catamarca, Argentina A study of siliceous microremains from a first millennium terrace systems in The Ambato Valley, southern Andes, Catamarca, Argentina

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    Alejandro Fabián Zucol

    2012-07-01

    Full Text Available Se analizó la composición de microrrestos silíceos de la secuencia sedimentaria de tres tipos de estructuras de cultivo de la localidad Los Varela (Valle de Ambato, provincia de Catamarca, Argentina. El análisis comparativo de las asociaciones de microrrestos (con especial hincapié en sus fitolitos permitió zonificar y diferenciar las secuencias sedimentarias de las distintas estructuras analizadas. La presencia en elevada abundancia relativa de fitolitos no producidos por los componentes vegetales dominantes de la flora local hace suponer el origen antrópico de parte de los microrrestos hallados, los cuales se vinculaban principalmente a elementos graminoideos panicoides, como así también con palmeras, bambúes y dicotiledóneas. Por otra parte, la presencia de ciertos tipos de microrrestos no fitolíticos podrían ser potenciales indicadores de prácticas de irrigación en algunas asociaciones de estas secuencias.Siliceous microremain components of the sedimentary sequence from three agricultural terrace types from Los Varela locality, Ambato, Catamarca province, Argentina were analyzed. The comparative analysis of microremain assemblages (with special emphasis on their phytoliths allowed zonification of the sequences and differentiation between some sections of the structures to be established. The presence in high relative abundance of phytoliths produced by non-dominant local flora suggests the anthropogenic origin of these phytoliths, which are linked mainly with panicoid grasses, palms, bamboos and dicots. Moreover, the presence of certain non-phytolith microremains may indicate irrigation practices in some assemblages within these sequences.

  17. Edad y caracterización de una mica de litio asociada a un sistema de greisen en Mina la Rosario, Sierra de Fiambalá, Catamarca Age and characterization of a lithium mica associated with a greisen system in the Rosario Mine, Sierra de Fiambalá, Catamarca

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    Julio C. Avila

    2008-03-01

    Full Text Available En el presente trabajo se realiza el estudio mineralógico y se define la edad de una mica de litio obtenida en las salbandas de las vetas cuarzo portadoras de wolframita de mina La Rosario, ubicada en las proximidades del granito Ayacucho, Sierra de Fiambalá, Sierras Pampeanas Occidentales de la provincia de Catamarca. Esta especie mineral fue identificada a través de diferentes técnicas analíticas que incluyen determinaciones por difracción de rayos X, análisis químicos y por espectrometría infrarroja. Los resultados de los estudios indican que su estructura corresponde a una zinnwaldita y su composición química permite ubicarla dentro de la serie biotita-siderofilita-zinnwaldita-lepidolita. Las edades isotópicas obtenidas para el Granito Ayacucho (340 ± 8 Ma y esta mica hidrotermal (339 ± 8 Ma confirman una edad carbonífera para este intrusivo y la estrecha relación temporal con la mineralización hidrotermal asociada.This work deals with a mineralogical study and the age of a lithium mica obtained from the selvage of wolframite quartz veins from La Rosario mine, which crops out close to Ayacucho Granite, Sierra de Fiambalá, Sierras Pampeanas Occidentales of Catamarca province. This mineral species was identified through different analytical techniques that include X-ray diffraction, chemical analyses and infrared spectrometry analyses. The results of the studies indicate that its structure corresponds to zinnwaldite and its chemical composition allows locating it inside the biotite-siderophyllite-zinnwaldite-lepidolite series. The isotopic ages obtained for the Ayacucho granite (340 ± 8 Ma and this hydrothermal mica (339 ± 8 Ma confirm a Carboniferous age for this intrusive and the genetic link with hydrothermal mineralization.

  18. Muestreo y análisis de desechos de talla. Un caso de estudio: Capa 2 Peñas de la Cruz 1.1 (Antofagasta de la Sierra, Catamarca Sampling techniques in lithic debitage analysis: A case study: layer 2 Peñas De La Cruz 1.1 site, Antofagasta de la Sierra, Catamarca

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    Jorge Alejandro Funes Coronel

    2012-07-01

    Full Text Available Este trabajo explora la incorporación de técnicas de muestreo en el análisis de desechos de talla. El objetivo general es la obtención de muestras que representen al conjunto de donde proceden, en este caso, los desechos de talla recuperados de la capa 2 (2° del sitio Peñas de la Cruz 1.1, localizado en Antofagasta de la Sierra, Catamarca. A fin de lograr lo propuesto se evalúan los alcances y limitaciones de tres tipos de muestreo aplicados en un mismo lote. Con el objeto de dar cuenta de las actividades de talla llevadas a cabo en el sitio, se presentan los resultados del análisis técnico-morfológico llevado a cabo sobre una muestra de desechos de talla (n= 300 extraída de un lote mayor (N= 2377.This paper explores the incorporation of sampling techniques in lithic débitage analysis. The overall objective is to obtain samples representative of the entire set from which they originated, in this case, débitage recovered from layer 2 from Peñas de la Cruz 1.1 site in Antofagasta de la Sierra, Catamarca. In order to accomplish this goal, the limitations of three types of sampling applied to the same lot were evaluated. With the goal of revealing the lithic production activities carried out at the site, the results of the technological analysis of a sample of materials (n= 300 collected from a larger lot (N= 2377 are presented.

  19. Motivos porque y para" en la tecnología lítica de un sitio formativo en el valle de Yocavil, provincia de Catamarca " reasons why and what for" in the lithic technology of a formative site in the Yocavil valley, Catamarca province

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    Juan Pablo Carbonelli

    2011-07-01

    Full Text Available En este trabajo presentamos un acercamiento desde la fenomenología a la tecnología lítica de un sitio formativo, Soria 2, ubicado en Andalhuala Banda, Valle de Yocavil, provincia de Catamarca. El objetivo es establecer la interrelación existente entre los sujetos sociales y las materias primas en un sitio de características domésticas. Para ello, reconstruimos las secuencias de producción de las materias primas más relevantes, observamos el grado de inversión de trabajo efectuado sobre los instrumentos y los contextos en los cuales participaron. A partir de los resultados obtenidos, pudimos observar que existió una explotación diferencial de las materias primas. Cada una de ellas fue tipificada de manera distinta, de acuerdo con el conjunto de motivaciones puesto en acto al momento de transformarlas en instrumentos. Los datos obtenidos adquieren relevancia a la luz de la escasez de información sobre tecnología lítica de las sociedades formativas de los valles.In this paper a phenomenological approach to the lithic technology of a formative site, Soria 2, Banda Andalhuala, Yocavil Valley, Catamarca Province, is presented. The objective is to establish the interrelationship between social subjects and raw materials in a site with domestic characteristics. As such, the production sequence of the most relevant raw materials are reconstructed and the amount of labor invested in the tools and the contexts in which they participated are noted. From the results it was observed that there was a differential exploitation of raw materials. Each was categorized differently according to the motivations that were put into play at the moment of their transformation into instruments. The data obtained is important because of the lack of information on the lithic technology of the valley’ s formative societies.

  20. Geología de la región del Cerro Guanaquero, Río Diamante, Mendoza Geology of Cerro Guanaquero region, Diamante River, Mendoza

    OpenAIRE

    Federico Fuentes; Ramos,Victor A.

    2008-01-01

    El estudio realizado presenta nuevos datos sobre un sector poco conocido de la Cordillera Principal de Mendoza, en la alta cuenca del río Diamante en las adyacencias del cerro Guanaquero, y los primeros datos geocronológicos de sus rocas volcánicas. Las unidades geológicas presentes en el área se dividen en cuatro grupos principales: secuencias sedimentarias mesozoicas marinas y continentales intensamente plegadas y falladas; intrusivos y volcanitas intermedias de edad neógena; rocas volcánic...

  1. Case history report on East Mesa and Cerro Prieto geothermal fields

    Energy Technology Data Exchange (ETDEWEB)

    Davis, DG.; Sanyal, S.K.

    1979-06-01

    Well log analysis as applied to the geothermal industry is one of the areas of technology in great need of further development. One means of improving log analysis technology is to study case histories of the past uses of log analysis as applied to specific fields. The project described in this report involved case history studies on two well-known geothermal areas in North America: the East Mesa field in California and the Cerro Prieto field in Mexico. Since there was considerably more pertinent material available on East Mesa, a major part of the effort on this project was devoted to studying the East Mesa field. One particular problem that first came to attention when studying the Cerro Prieto data was the difficulty in determining actual formation temperature at the time of logging. Since the temperature can have a significant effect on well log readings, an accurate temperature determination was considered to be important.

  2. H2S and CO2 emissions from Cerro Prieto geothermal power plant, Mexico

    Science.gov (United States)

    Peralta, Oscar; Franco, Luis; Castro, Telma; Taran, Yuri; Bernard, Ruben; Inguaggiato, Salvatore; Navarro, Rafael; Saavedra, Isabel

    2014-05-01

    Cerro Prieto geothermal power plant has an operation capacity of 570 MW distributed in four powerhouses being the largest geothermal plant in Mexico. The geothermal field has 149 production wells. It is located in Cerro Prieto, Baja California, 30 km to the south of the Mexico-US border. Two sampling campaigns were performed in December 2012 and May 2013 where geothermal fluids from 46 production wells and 10 venting stacks were obtained and analyzed by gas chromatography coupled to mass spectrometry. Average CO2 and H2S composition of samples from venting stacks were 49.4% and 4.79%, respectively. Based on the chemical composition of samples, the geothermal power plant emits every day from venting stacks 869 tons of CO2, plus 68 tons of H2S, among other non-condensable gases.

  3. Occurrences of alunite, prophyllite, and clays in the Cerro La Tiza area, Puerto Rico

    Science.gov (United States)

    Hildebrand, Fred Adelbert; Smith, Raymond J.

    1959-01-01

    A deposit of hydrothermally altered rocks in the Cerro La Tiza area located between the towns of Comerio and Aguas Buenas, approximately 25 kilometers southwest of San Juan, Puerto Rico, was mapped and studied to determine the principal minerals, their extent distribution and origin, and the possibility of their economic utilization, especially in Puerto Rico. The Cerro la Tiza area is about 7? kilometers long, has an average width of about 1? kilometers and embraces a total area of approximately 15 square kilometers. The principal mineralized zone, a dike-like mass of light-colored rocks surrounded by dark-colored volcanic country rocks, occupies the crest and upper slopes of east-trending Cerro La Tiza ridge and is believed to be of Late Cretaceous or Eocene age. This zone is approximately 5,300 meters long, 430 meters wide and has an area of approximately 225 hectares (556 acres). The rocks of the mineralized zone are of mixed character and consist mainly of massive quartzose rocks and banded quartz-alunite rocks closely associated with foliated pyrophyllitic, sericitic and clayey rocks. The principal minerals in probably order of abundance are quartz, alunite, pyrophyllite, kaolin group clays (kaolinite and halloysite) and sericite. Minerals of minor abundance are native sulfure, diaspore, svanbergite (?), sunyite (?), hematite, goethite, pyrite, rutile (?) and very small quantities of unidentified minerals. The mineralized zone has broken down to deposits of earth-rock debris of Quaternary age that cover much of the slopes and flanks of Cerro La Tiza. This debris consists generally of fragments and boulders with a very large size range embedded in a clayey matrix. The distribution of the earth-rock debris with respect to the present topography and drainage suggests that it may have undergone at least two cycles of erosion. Underlying the earth-rock debris and completely enclosing the mineralized zone are country rocks of probably Late Cretaceous age. These

  4. Progress report on LBL's numerical modeling studies on Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Halfman-Dooley, S.E.; Lippman, M.J.; Bodvarsson, G.S.

    1989-04-01

    An exploitation model of the Cerro Prieto geothermal system is needed to assess the energy capacity of the field, estimate its productive lifetime and develop an optimal reservoir management plan. The model must consider the natural state (i.e., pre-exploitation) conditions of the system and be able to predict changes in the reservoir thermodynamic conditions (and fluid chemistry) in response to fluid production (and injection). This paper discusses the results of a three-dimensional numerical simulation of the natural state conditions of the Cerro Prieto field and compares computed and observed pressure and temperature/enthalpy changes for the 1973--1987 production period. 16 refs., 24 figs., 2 tabs.

  5. Seismicity studies in the region of the Cerro Prieto Geothermal Field

    Energy Technology Data Exchange (ETDEWEB)

    Albores, A.; Reyes, A.; Brune, J.N.; Gonzalez, J.; Garcilazo, L.; Suarez, F.

    1980-01-01

    This paper reports results from seismicity studies in the region of the Cerro Prieto geothermal field. These studies were conducted with local short period seismic arrays during 1974-1975 and 1977-1978. During the latter period, horizontal seismometers were used for better control on the S-wave arrival times. Locations were obtained for about 200 events and composite fault plane solutions were obtained for five groups of events. 16 refs.

  6. Identification of fluid-flow paths in the Cerro Prieto geothermal field

    Science.gov (United States)

    Halfman, S. E.; Lippmann, M. J.; Zelwer, R.; Howard, J. H.

    1982-05-01

    A hydrogeologic model of the Cerro Prieto geothermal field has been developed based on geophysical and lithologic well logs, downhole temperature, and well completion data from about 90 deep wells. The hot brines seem to originate in the eastern part of the field, flowing in a westward direction and rising through gaps in the shaly layers which otherwise act as partial caprocks to the geothermal resource.

  7. The age and constitution of Cerro Campanario, a mafic stratovolcano in the Andes of central Chile

    Science.gov (United States)

    Hildreth, W.; Singer, B.; Godoy, E.; Munizaga, F.

    1998-01-01

    Cerro Campanario, a towering landmark on the continental divide near Paso Pehuenche, is a glacially eroded remnant of a mafic stratovolcano that is much younger than previously supposed. Consisting of fairly uniform basaltic andesite, rich in olivine and plagioclase, the 10-15 km3 edifice grew rapidly near the end of the middle Pleistocene, about 150-160 ka, as indicated by 40Ar/39Ar and unspiked K-Ar analyses of its lavas.

  8. A review of the hydrogeologic-geochemical model for Cerro Prieto

    Science.gov (United States)

    Lippmann, M.J.; Truesdell, A.H.; Halfman-Dooley, S. E.; Mañónm, A.

    1991-01-01

    With continued exploitation of the Cerro Prieto, Mexico, geothermal field, there is increasing evidence that the hydrogeologic model developed by Halfman and co-workers presents the basic features controlling the movement of geothermal fluids in the system. In mid-1987 the total installed capacity at Cerro Prieto reached 620 MWc, requiring a large rate of fluid production (more than 10,500 tonnes/hr of a brine-steam mixture; August 1988). This significant mass extraction has led to changes in reservoir thermodynamic conditions and in the chemistry of the produced fluids. Pressure drawdown has caused an increase in cold water recharge in the southern and western edges of the field, and local and general reservoir boiling in parts of the geothermal system. After reviewing the hydrogeologic and geochemical models of Cerro Prieto, the exploitation-induced cold water recharge and reservoir boiling (and plugging) observed in different areas of the field, are discussed and interpreted on the basis of these models and schematic flow models that describe the hydrogeology. ?? 1991.

  9. Evolution of the Cerro Prieto geothermal system as interpreted from vitrinite reflectance under isothermal conditions

    Energy Technology Data Exchange (ETDEWEB)

    Barker, C.E. (US Geological Survey, Denver, CO); Pawlewicz, M.J.; Bostick, N.H.; Elders, W.A.

    1981-01-01

    Temperature estimates from reflectance data in the Cerro Prieto system correlate with modern temperature logs and temperature estimates from fluid inclusion and oxygen isotope geothermometry indicating that the temperature in the central portion of the Cerro Prieto System is now at its historical maximum. Isoreflectance lines formed by contouring vitrinite reflectance data for a given isothermal surface define an imaginary surface that indicates an apparent duration of heating in the system. The 250/sup 0/C isothermal surface has a complex dome-like form suggesting a localized heat source that has caused shallow heating in the central portion of this system. Isoreflectance lines relative to this 250/sup 0/C isothermal surface define a zone of low reflectance roughly corresponding to the crest of the isothermal surface. Comparison of these two surfaces suggest that the shallow heating in the central portion of Cerro Prieto is young relative to the heating (to 250/sup 0/C) on the system margins. Laboratory and theoretical models of hydrothermal convection cells suggest that the form of the observed 250/sup 0/C isothermal surface and the reflectance surface derived relative to it results from the convective rise of thermal fluids under the influence of a regional hydrodynamic gradient that induces a shift of the hydrothermal heating effects to the southwest.

  10. Relationship between water chemistry and sediment mineralogy in the Cerro Prieto geothermal field: a preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Valette-Silver, J.N. (Univ. de Perpignan, France); Thompson, J.M.; Ball, J.W.

    1981-01-01

    The chemical compositions of waters collected from the Cerro Prieto geothermal production wells and hydrothermal emanations are different. Compared to the Cerro Prieto well waters, the surficial waters generally contain significantly less potassium, slightly less calcium and chloride, and significantly more magnesium and sulfate. In comparison to the unaltered sediments, the changes in the mineralogy of the altered sediments appear to be controlled by the type of emanation (well, spring, mud pot, geyser, fumarole, or cold pool). However, an increase in quartz and potassium feldspar percentages seems to be characteristic of the majority of the sediments in contact with geothermal fluids. Preliminary attempts to model the chemical processes occurring in the Cerro Prieto geothermal field using chemical equilibrium calculations are reported. For this purpose the chemical compositions of thermal waters (well and surficial emanation) were used as input data to make calculations with SOLMNEQ and WATEQ2 computer programs. Then the theoretical mineral composition of altered sediments was predicted and compared to the mineralogy actually observed in the solid samples.

  11. Materiales del Poblado de las Paredejas en el Cerro del Berrueco. Una Nueva Arracada

    Directory of Open Access Journals (Sweden)

    Carlos PIÑEL

    2009-10-01

    Full Text Available Queremos dar a conocer con esta nota el interesante hallazgo de una arracada de oro en el yacimiento de «Las Paredejas» o «Santa Lucía», en el Cerro del Berrueco, así como de otros objetos, procedentes del mismo lugar, que quizá nos acerquen a un conocimiento de la joyería occidental durante la 2.a Edad del Hierro en la Península y por otra parte a una mayor aclaración del conjunto arqueológico que constituye el Cerro del Berrueco, dos de cuyos poblados fueron estudiados por Maluquer: el yacimiento de «La Mariselva», situado en la ladera meridional del Berroquillo, perteneciente al Bronce I y II y el del «Canoho Enamorado», situado este último en la parte alta del Cerro y desarrollándose durante la 1.a Edad del Hierro, a partir de cuya fecha surgen los poblados que se localizan en la base.

  12. Campos comuneros en el valle de Hualfín (Catamarca. Antecedentes, problemática y situación actual

    Directory of Open Access Journals (Sweden)

    Bernarda Zubrzycki

    2002-01-01

    Full Text Available En este artículo nos proponemos caracterizar el régimen de tenencia de la tierra de tres campos comuneros ubicados en el valle de Hualfín, específicamente en el Distrito La Ciénaga (Catamarca, Argentina, así como indagar el origen y evolución de algunas de las poblaciones actualmente presentes en ellos. Estos campos tienen su antecedente en las mercedes de tierra otorgadas por la corona durante la época colonial; a través del tiempo se fueron vendiendo, heredando y donando derechos y acciones de uso sobre los mismos, dando lugar a una compleja situación jurídica respecto a la propiedad. Aún hoy ningún habitante de las poblaciones analizadas en este trabajo ha iniciado juicios sucesorios, deslindes o mensuras para prescripciones adquisitivas, legitimando en muchos casos su derecho a la tierra a través del parentesco con los primeros propietarios.

  13. Mineralogical Characterization Of Topaz From Miarolitic Pegmatites And W-Bearing Greisen In The A-Type El Portezuelo Granite, Papachacra (Catamarca Province

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    Fernando Colombo

    2009-04-01

    Full Text Available The El Portezuelo Granite (Catamarca Province, NW Argentina, probably of Late Devonian or Early Carboniferous age, was emplaced at ≤ 2 kbar and displays the chemical characteristics of an A-type granite. It hosts small miarolitic pegmatites and dikes that belong to the NYF petrogenetic family, miarolitic class, miarolitic-REE subclass, with features more similar to those reported for the gadolinite-fergusonite type. Topaz is widespread both in pegmatites and in a W-bearing greisen genetically related to the granite. In pegmatites it occurs as crystals up to over 15 cm long, showing the forms {120} and {041} (dominant, and also {100}, {010}, {001}, {110}, {130}, {230}, {410}, {150}, {340}, {201}, {203}, {011}, {021}, {031}, {111}, {112}, {221}, {223}, and {445}. Crystals are colorless to pale yellow, more rarely brownish or bluish. Electron-microprobe analyses of gemmy crystals from pegmatites and greisen show that topaz is F-rich (between 19.01 and 20.12 wt. % F, most crystals being slightly zoned and has very low MgO and TiO2 (≤ 0.02 wt.%, low FeO (≤; 0.03 wt.%, and up to 0.10 wt.% CaO. Refractive indices and unit-cell dimensions reflect the F-rich nature of the studied topaz. This occurrence produces the finest crystals yet known from western South America but probably has no economic potencial as gemstock producer.

  14. Edad y caracterización de una mica de litio asociada a un sistema de greisen en Mina la Rosario, Sierra de Fiambalá, Catamarca

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    Julio C. Avila

    2008-03-01

    Full Text Available En el presente trabajo se realiza el estudio mineralógico y se define la edad de una mica de litio obtenida en las salbandas de las vetas cuarzo portadoras de wolframita de mina La Rosario, ubicada en las proximidades del granito Ayacucho, Sierra de Fiambalá, Sierras Pampeanas Occidentales de la provincia de Catamarca. Esta especie mineral fue identificada a través de diferentes técnicas analíticas que incluyen determinaciones por difracción de rayos X, análisis químicos y por espectrometría infrarroja. Los resultados de los estudios indican que su estructura corresponde a una zinnwaldita y su composición química permite ubicarla dentro de la serie biotita-siderofilita-zinnwaldita-lepidolita. Las edades isotópicas obtenidas para el Granito Ayacucho (340 ± 8 Ma y esta mica hidrotermal (339 ± 8 Ma confirman una edad carbonífera para este intrusivo y la estrecha relación temporal con la mineralización hidrotermal asociada.

  15. Chironomidae (Diptera en cursos de agua de Puna y Chaco Serrano de Catamarca (Argentina: primeros registros y distribución de géneros y especies

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    Gretel N. RODRÍGUEZ GARAY

    2015-01-01

    Full Text Available La distribución en América del Sur (Region Neotropical de Stictocladius prati Saether & Cranston, Podonomus. regalis Brundin y P. setosus Brundin 1966 es ampliada a partir de primeros registros de la Argentina. Podonomus fastigians Brundin, y Allocladius quadrus Andersen et al. se citan por primera vez de Catamarca Se describe el morfotipo pupal de Barbadocladius sp. “Chaco” (cerca de B. andinus Cranston & Krosh. Se incorporan las variables ambientales de los cursos de agua donde se registraron las especies. Los ríos de Puna presentan aguas muy alcalinas, pH (8.12-8.8, alta conductividad y alto contenido en MO, mientras que el arroyo de Chaco Serrano es de aguas débilmente alcalinas, pH (7, baja conductividad y bajo contenido en materia orgánica (MO. Las especies Stictocladius prati, Allocladius quadrus, Podonomus fastigians, P. setosus y P. regalis estuvieron presentes en ríos de altura con aguas alcalinas y alta conductividad, mientras Barbadocladius sp. “Chaco” se registró en un arroyo de menor altura, con aguas de baja alcalinidad y conductividad.

  16. New data on the bottom topography, recent sedimentation and water balance of Cerro Prieto dam, Mexico

    Science.gov (United States)

    Yutsis, Vsevolod; Levchenko, Oleg; Lowag, Jens; Krivosheya, Konstantin; de León Gómez, Héctor; Kotsarenko, Anatolyi

    2010-05-01

    Cerro Prieto Dam, a small water reservoir in the NE Mexico, is characterized by very high velocity of recent sedimentation, high sub-bottom seepage and erosion, and as a result, nonlinear water balance. These phenomenons never were studied since construction of the dam in the beginning of 1980th. So the goal of our work was to investigate the bottom topography and also sub-bottom near surface structure using the parametric acoustical effect. High-resolution sub-bottom profiling, using the Innomar SES-2000 compact echosounder, was carried out in Cerro Prieto Dam during February-April of 2008. The survey was conducted onboard of a small motor boat. The SES transducer was mounted on the front side of the boat using light metal pipe, and all electronic equipment was installed on the deck. Accurate positioning of the boat was reached by GPS. Average speed was 8-10 km/h. Innomar's software tool ISE was provides near real-time post-processing of the collected SES data and operation procedure could be corrected on-line. Acoustic signal ensured vertical resolution of 10-15 cm at acceptable penetration up to 15 m. Bathymetry map was compiled assuming average sound velocity of 1450 m/s. The irregular bottom topography of Cerro Prieto dam was discovered. The present elevation of the water surface is about 181 m above see level, and the lake depth varies from 1-2 to 28 m. The SES records show a distinct bottom layer of recent sediments by 0.5 - 4 m thickness which follows reservoir floor topography. Very specific acoustic anomalies, which seem to be related with gas sediments, are observed. The integrated SES, gravity, magnetic and geoelectrical data interpretation allows assuming a series of the superficial fractures focused in a NW direction, perpendicular (NE-SW) to the general deep fault zone. Hydrological balance for the Cerro Prieto water reservoir has been analyzed for last two decades. There are three types of water level fluctuations on the Cerro Prieto dam: long

  17. El recorrido al Cerro Gordo y el ritual tepehuano de las ofrendas en los cerros de la comunidad de San Bernardino de Milpillas

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    Chantal CRAMAUSSEL

    2014-01-01

    Full Text Available El ritual de las ofrendas es una ceremonia propiciatoria de la lluvia que se efectúa al terminar la estación seca en los cerros más altos de la comunidad de San Bernardino de Milpillas Chico, en la Sierra Tepehuana del estado de Durango. A esos rituales distintos de los cató- licos que forman parte del ciclo anual de costumbre concurren las autoridades civiles, los curanderos y miembros del Consejo de ancianos. Es un momento muy importante en el que se refuerza la cohesión de los tepehuanos que tienen un patrón de asentamiento muy disperso, como los demás grupos del norte, pero sus rituales presentan también similitudes con los mesoamericanos.

  18. Areas to explore surrounding the Cerro Prieto geothermal field, BC; Areas para exploracion en los alrededores del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar Dumas, Alvaro [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, Baja California (Mexico)]. E-mail: alvaro.aguilar@cfe.gob.mx

    2009-07-15

    Exploration plays an important role in tapping underground natural resources-whether water, oil, natural gas or minerals. Exploratory data allow us to learn reservoir conditions, increasing probable reserves and reservoir life span. Around the Cerro Prieto geothermal field, BC, and in the Mexicali Valley in general, exploration had almost stopped but recently was resumed by the Studies Division of Comision Federal de ELectricidad (CFE)'s Gerencia de Proyectos Geotermoelectricos. The division sent technical personnel to structurally map the northern and eastern portions of Laguna Salada. The paper offers a general outline of the main zones undergoing exploratory studies-studies perhaps culminating in siting exploratory wells to locate more geothermal resources (and ultimately producing them using binary power plants). CFE also wants to site injection wells west of the current production zone, and this is covered, as well. All activities are meant to increase the productive lifespan of the geothermal reservoir. [Spanish] Cuando se trata de la explotacion de recursos naturales del subsuelo, sea agua, gas, petroleo o minerales, la exploracion juega un papel muy importante, ya que permite conocer las condiciones del yacimiento que pudieran llevar a incrementar las reservas de los recursos explotados y extender su vida util. En las zonas aledanas al campo geotermico de Cerro Prieto, BC, y en general en el Valle de Mexicali, la exploracion estaba practicamente detenida habiendose reactivado a raiz de que la Subgerencia de Estudios de la Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad (CFE) envio personal para realizar mapeos estructurales en las porciones norte y oriente de la Laguna Salada. Este trabajo presenta un panorama general de las areas prioritarias para realizar estudios exploratorios y poder programar, con mas bases, pozos exploratorios enfocados a localizar mas recursos geotermicos, inclusive para generar energia por medio

  19. Basic aspects of the Cerro Prieto reservoir water recharge; Aspectos basicos de la recarga de agua al reservorio de Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Mercado, Sergio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1991-12-31

    The Cerro Prieto geothermal field, located 30 km South of Mexicali City, Baja California, has at present an installed capacity of 620 MW in geothermal power plants, that operating with endogenous steam, make use of the underground energy by means of deep wells, from which about 80 million cubic meters per year of high enthalpy water and steam mixture are extracted. During the exploitation physical an chemical changes in the hydrothermal fluids discharged by the wells have been detected, which shows, among other things, an elevated water recharge, located towards the West area of the field and a low recharge in the part of the east zone area. For this reason the hot brine waste re-injection is recommended, (previously treated to eliminate the silica excess) to thermally an hydraulically recharge the reservoir in that part of the field. [Espanol] El campo geotermico de Cerro Prieto, situado a 30 km al sur de la ciudad de Mexicali, Baja California, cuenta actualmente, despues de 18 anos en explotacion, con 620 MW de capacidad instalada en plantas geotermoelectricas que, operando con vapor endogeno, aprovechan la energia del subsuelo mediante pozos profundos de los que se extraen alrededor de 80 millones de metros cubicos por ano de una mezcla de agua vapor de elevada entalpia. Durante la explotacion se han percibido cambios fisicos y quimicos en los fluidos hidrotermales descargados por los pozos, lo que indica, entre otras cosas, una recarga elevada de agua localizada hacia el poniente del campo y una recarga baja en una zona de la parte oriental. Por ello se recomienda la reinyeccion de salmuera geotermica caliente de desecho (previamente tratada para eliminar el exceso de silice) para recargar termica e hidraulicamente el reservorio en esa parte del campo.

  20. Reconnaissance study of late quaternary faulting along cerro GoDen fault zone, western Puerto Rico

    Science.gov (United States)

    Mann, P.; Prentice, C.S.; Hippolyte, J.-C.; Grindlay, N.R.; Abrams, L.J.; Lao-Davila, D.

    2005-01-01

    The Cerro GoDen fault zone is associated with a curvilinear, continuous, and prominent topographic lineament in western Puerto Rico. The fault varies in strike from northwest to west. In its westernmost section, the fault is ???500 m south of an abrupt, curvilinear mountain front separating the 270- to 361-m-high La CaDena De San Francisco range from the Rio A??asco alluvial valley. The Quaternary fault of the A??asco Valley is in alignment with the bedrock fault mapped by D. McIntyre (1971) in the Central La Plata quadrangle sheet east of A??asco Valley. Previous workers have postulated that the Cerro GoDen fault zone continues southeast from the A??asco Valley and merges with the Great Southern Puerto Rico fault zone of south-central Puerto Rico. West of the A??asco Valley, the fault continues offshore into the Mona Passage (Caribbean Sea) where it is characterized by offsets of seafloor sediments estimated to be of late Quaternary age. Using both 1:18,500 scale air photographs taken in 1936 and 1:40,000 scale photographs taken by the U.S. Department of Agriculture in 1986, we iDentified geomorphic features suggestive of Quaternary fault movement in the A??asco Valley, including aligned and Deflected drainages, apparently offset terrace risers, and mountain-facing scarps. Many of these features suggest right-lateral displacement. Mapping of Paleogene bedrock units in the uplifted La CaDena range adjacent to the Cerro GoDen fault zone reveals the main tectonic events that have culminated in late Quaternary normal-oblique displacement across the Cerro GoDen fault. Cretaceous to Eocene rocks of the La CaDena range exhibit large folds with wavelengths of several kms. The orientation of folds and analysis of fault striations within the folds indicate that the folds formed by northeast-southwest shorTening in present-day geographic coordinates. The age of Deformation is well constrained as late Eocene-early Oligocene by an angular unconformity separating folDed, Deep

  1. ANÁLISIS FUNCIONAL DEL CONJUNTO ARQUITECTÓNICO RCH 8, LOCALIDAD ARQUEOLÓGICA DE RINCÓN CHICO, VALLE DE YOCAVIL, CATAMARCA / Functional analysis of architectural unit RCh 8 at the archaeological site of Rincón Chico, Yocavil valley, Catamarca.

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    Fernando Gabriel Cabrera

    2015-06-01

    Full Text Available El presente trabajo evalúa desde una escala micro las evidencias recuperadas en el conjunto residencial Rincón Chico 8 (RCh 8, emplazado en el sector bajo de la localidad arqueológica de Rincón Chico, Santa María, Valle de Yocavil, Catamarca. Dos fechados lo adscriben al Período de los Desarrollos Regionales (siglos IX-XV. Conjuntos arquitectónicamente similares fueron mencionados por primera vez por Ambrosetti (1897 para Quilmes y fueron propuestos como unidades habitacionales, interpretación que fue retomada por otros autores. Las evidencias recuperadas y los rasgos arquitectónicos en el conjunto RCh 8 permiten plantear su uso como unidad habitacional, no obstante, exhibe discrepancias con lo propuesto por Ambrosetti ya que se encontraron diferencias en la distribución de las actividades entre las estructuras que lo componen y en rasgos arquitectónicos postulados como propios de los conjuntos. Las implicancias asociadas resultan relevantes para la revaluación de propuestas vinculadas a los asentamientos del valle de Yocavil, como el tamaño de los grupos que las habitaron o la escala de almacenamiento.  Abstract  The present article evaluates, at the micro-scale, the recovered evidence at the Rincón Chico (RCh 8 residential complex, located in the lower sector of the archaeological site of Rincón Chico, Santa María, Valle de Yocavil, Catamarca. Two dates place the site in the Regional Developments Period (9th-15th Century AD. Ambrosetti (1897 first described similar architectural structures for the site of Quilmes, interpreting them as residential units; this interpretation has been accepted by other scholars. Evidence recovered as well as the architecture of the RCh 8 assemblage allow for their use as residential units. Nevertheless, there are certain discrepancies between what Ambrosetti proposes and our evidence such as differences in the distribution of activities in the structures and in the architectural components

  2. ZOOARQUEOLOGÍA Y TAFONOMÍA DEL PERÍODO TARDÍO-INCA EN PEÑAS COLORADAS, ANTOFAGASTA DE LA SIERRA (PUNA DE CATAMARCA, ARGENTINA/Zooarchaeology and taphonomy of the Late Period-INCA in Peñas Coloradas, Antofagasta de la Sierra (Puna of Catamarca, Argentina

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    Jorge Guillermo Ortiz

    2012-11-01

    Full Text Available Se presenta el análisis integrado del conjunto arqueofaunístico, constituido por vertebrados e invertebrados, del sitio Peñas Coloradas 3-cumbre (PC3-c, Antofagasta de la Sierra (Catamarca, Argentina. El sitio se localiza en la cumbre de un farallón de ignimbrita y está conformado por estructuras arquitectónicas asignadas a momentos Tardíos-Incas, algunas de las cuales han sido reutilizadas hasta principios del siglo XX. Con la finalidad de complementar los datos y reconstruir la historia tafonómica de los conjuntos faunísticos, se estudió el contexto sedimentario mediante métodos físico-químicos (textura; pH; determinación de albúmina, P y MO. Los materiales analizados brindaron datos sobre algunas de las actividades realizadas en las estructuras, el consumo de animales, temporalidad, estacionalidad de las ocupaciones, y sobre los procesos diagenéticos actuantes. La integración contextual de los datos materiales analizados y del emplazamiento del sitio y sus estructuras, nos permite inferir prácticas sociales diferenciadas entre las estructuras con cubierta y sin cubierta. Las primeras, se vinculan a depósitos de alimentos y manufacturas, mientras que las segundas se asocian con  prácticas residenciales, procesamiento y consumo de alimentos. Abstract In this paper, an integrated analysis of archaeofaunal data consisting of vertebrates and invertebrates of the Peñas Coloradas 3-summit (PC3-c, Antofagasta de la Sierra (Catamarca, Argentina is conducted. The site is located at the top of an ignimbrite hill and is composed of architectural structures attributed to Late Inca times, some of which had been re-used until the early 20th century. In order to complement the data and reconstruct the taphonomic history of the faunal assemblages, we studied the sedimentary context by physicochemical methods (texture, pH, determination of albumin, P and MO. The material tested has provided data on some of the activities in the structures

  3. Análisis tecno-tipológico de los artefactos líticos de la Loma de los Antiguos de Azampay (Departamento de Belén, Catamarca TECHNO-TYPOLOGICAL ANALYSES OF LITHIC ARTIFACTS FROM LOMA DE LOS ANTIGUOS DE AZAMPAY, DEPARTMENT OF BELÉN, CATAMARCA

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    Marina C. Flores

    2009-12-01

    Full Text Available En el presente trabajo se analizan los artefactos líticos tallados y de molienda pertenecientes a la Loma de los Antiguos (Departamento de Belén, Catamarca. Este sitio arqueológico está conformado por 43 estructuras rodeadas por murallas defensivas y se sitúa sobre una lomada de 200 m de altura. Distintas vías de análisis (la cerámica, la arquitectura y los fechados radiocarbónicos asocian la ocupación del poblado a grupos de la cultura Belén, entre fines del período de Desarrollos Regionales y la conquista inkaica. A partir de un estudio exploratorio de los materiales líticos se busca generar información acerca de las materias primas explotadas y de la producción lítica desarrollada en este sitio. Entre los artefactos líticos tallados observamos tanto el manejo de materias primas de origen volcánico como sedimentario. Entre las rocas volcánicas, la obsidiana se destaca por su mayor porcentaje y distribución dentro del sitio, en comparación con el resto de los materiales líticos (areniscas, basaltos y rocas pelíticas. Esta materia prima se encuentra asociada a puntas de proyectil y parece haber sido explotada exhaustivamente. Entre los artefactos de molienda se recuperaron manos de molino en granito y arenisca, así como un lito modificado por uso.In this paper the chipped stone artifacts and grinding stone tools recovered at Loma de los Antiguos, Belén, Catamarca, are analyzed. This archaeological site consists of 43 structures surrounded by defensive walls and is located on a 200 m high hill. Different types of analysis (pottery, architectural and radiocarbon dating associate the occupation of this town to groups within the Belén culture, between the end of the Regional Developments period and the Inka conquest. An exploratory study of the lithic materials from the site generated information on raw material exploitation and lithic production. Among the chipped stone artifacts the use of different raw materials

  4. IDENTIFICACIÓN INTERESPECÍFICA DE CAMÉLIDOS EN EL VALLE DE AMBATO (CATAMARCA, ARGENTINA. UNA APROXIMACIÓN A LA PROBLEMÁTICA DESDE DISTINTAS LÍNEAS DE ANÁLISIS/Interspecific identification of camelids in Ambato valley (Catamarca, Argentina...

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    Mariana Dantas

    2012-11-01

    Full Text Available La identificación interespecífica de camélidos y la distinción entre morfotipos de llamas en los materiales óseos recuperados en sitios arqueológicos constituyen dos aspectos de suma importancia dentro de los estudios zooarqueológicos del noroeste argentino y de la región andina en general. En este trabajo se pretende contribuir a esta problemática, mediante el entrecruzamiento de distintas líneas de análisis aplicadas sobre los restos de camélidos procedentes del Valle de Ambato, Catamarca, entre los siglos VI y X d.C. De este modo, la integración de estudios osteométricos y de isótopos estables posibilitó establecer la existencia en este valle de camélidos domésticos en función de su tamaño relativo y una dieta selectiva concentrada en plantas C4. Dentro de aquellos también fue posible distinguir dos grupos que podrían responder a distintas variedades de tamaños: un grupo de animales de mayor porte, o llamas grandes, y otro de menor porte, o llamas pequeñas, cuyo tamaño se superpone con el rango de tamaños de los guanacos norandinos. En definitiva, se puede afirmar, que la combinación de ambos análisis permitió alcanzar un grado de diferenciación que de otro modo no hubiera sido posible.   Abstract   Interspecific identification of camelids and distinction between llamas’ morphotypes in bone materials from archaeological sites are two major aspects in zooarchaeological studies of northwestern Argentina and the Andean region in general. This paper aims at contributing to the issue along different analytical approaches applied to camelids remains from Ambato Valley, Catamarca, between the 6th and 10th centuries AD. Thus, the integration of osteometric and stable isotope studies allowed establishing/confirming the presence of domestic camelids in this valley, based on their relative size and a selective diet mostly derived from C4 plants. It was also possible to distinguish two probably differently-sized groups

  5. Análisis de la mortalidad infantil en la Pcia. de Catamarca durante el período 1998-2002

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    Silverio Reyes, M. J.

    2003-01-01

    Full Text Available Con el objeto de conocer la incidencia de las condiciones socio-económicas suscitadas durante los últimos años en la mortalidad infantil en la Pcia. de Catamarca, se realizó un análisis de los registros de estadísticas vitales de los años 1998 al 2002. Se determinaron las tasas de mortalidad infantil, las tasas específicas de mortalidad neonatal y postneonatal, en relación a causas de muerte que pueden ser relacionadas con condiciones de pobreza, así como la incidencia del bajo peso al nacer entre estas causas. Se observó un aumento significativo de la mortalidad infantil en el año 2002, cuya tasa resultó la más alta del quinquenio; de ella, la que corresponde al período neonatal, es la que particularmente origina este incremento. Con respecto a las causas de muerte relacionadas con la pobreza, se registra un incremento de la mortalidad infantil debida a ellas, siendo los valores observados en el 2002, también los mayores de los tres últimos años. Las muertes neonatales ocurridas por bajo peso, tuvieron un incremento no significativo en el último año. Otras causas relacionadas con la pobreza, son las que contribuirían mayormente al incremento de la mortalidad neonatal en los últimos dos años. Se concluye que a partir del momento de fuerte incidencia de la crisis socio-económica argentina, en la provincia se revirtió la tendencia decreciente de las tasas de mortalidad infantil y se diversificaron las causas de mortalidad relacionadas con la pobreza.

  6. Veta Esperanza Sudeste, un caso particular de enriquecimiento Supergénico en el yacimiento Alto de la blenda, distrito minero Agua de Dionisio, provincia de Catamarca

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    Natalia Salado Paz

    2011-06-01

    Full Text Available Veta Esperanza Sudeste se localiza en el distrito minero Agua de Dionisio, Catamarca, dentro de la provincia geológica de las Sierras Pampeanas Occidentales. La geología del mismo corresponde a rocas metamórficas de bajo grado y cuerpos ígneos intrusivos graníticos a granodioríticos paleozoicos, sedimentos clásticos continentales terciarios y rocas pertenecientes al Complejo Volcánico Farallón Negro del Mioceno. Además, a areniscas, tobas del Plioceno y depósitos fluviales del Cuaternario. En el distrito mineralizado hay yacimientos diseminados y vetiformes, entre los últimos se mencionan los depósitos de oro y plata de Farallón Negro y Alto de La Blenda. Veta Esperanza Sudeste es un importante prospecto nuevo del sistema Alto de La Blenda, tiene una corrida de 200 m, potencia entre 0,30 y 6 m, rumbo NO e inclinación variable con la profundidad entre 75° a 56° al NE. La roca de caja es cuarzo monzonita, donde se observaron diferentes tipos de alteración hidrotermal: argílica, sericítica, silícica y propilítica. Presenta oxidación intensa, que afecta también a la veta. La paragénesis corresponde a: (1 minerales primarios (hipogénicos, pirita, galena, esfalerita, calcopirita, sulfosales de plata y oro, y (2 secundarios (supergénicos, pirolusita, psilomelano, hematina-goethita y sulfuros como calcosina y covelina. Los valores de leyes son de 0,5 a 40 g/tn de Au y 40 a 2.000 gr/tn de Ag con un recurso potencial de aproximadamente 400.000 tn de mineral.

  7. Archaeological fieldwork in the Bronze Age site of Cerro de la Encina (Monachil, Granada

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    Aranda Jiménez, Gonzalo

    2005-06-01

    Full Text Available New archaeological fieldwork has been carried out from November 2003 to May 2004 in the Bronze Age site of Cerro de la Encina, due to the interest of the regional government of Andalusia in displaying the settlement for visitors. The aim of this fieldwork has been the systematic excavation of a large settlement area partially known thanks to the excavations developed at the beginning of 1980s. A first toccupation period belonging to the Argaric Culture has been documented, highlighting specially the funerary ritual characterized by individual inhumations located below dwellings. After a gap in the occupation of the settlement a new social group belonging to the Late Bronze Age Culture of Southeast of Spain inhabits the Cerro de la Encina.

    El interés de la Consejería de Cultura de la Junta de Andalucía por la musealización del yacimiento del Cerro de la Encina ha motivado el desarrollo de nuevas investigaciones arqueológicas cuya primera fase se ha desarrollado entre Noviembre de 2003 y Mayo de 2004. Los trabajos han consistido en la excavación sistemática de un área de poblado de grandes dimensiones parcialmente conocida por las investigaciones realizadas a principios de los años 80. Los resultados han sido del máximo interés documentándose un primer momento de ocupación perteneciente a la Cultura de El Argar en el que destaca su espectacular registro funerario integrado dentro de las áreas de habitación. Tras un periodo de abandono del yacimiento se produce una nueva ocupación correspondiente a una comunidad del Bronce Final del Sureste.

  8. Vitrinite reflectance geothermometry and apparent heating duration in the Cerro Prieto geothermal field

    Science.gov (United States)

    Barker, C.E.; Elders, W.A.

    1981-01-01

    Vitrinite reflectance measured in immersion oil (Ro) on kerogen extracted from hydrothermally altered mudstones in borehole M-84 at the Cerro Prieto geothermal field exhibit an increase in mean reflectance (Ro) from 0.12 per cent at 0.24 km depth to 4.1 per cent at 1.7 km depth. Downhole temperatures measured over this interval increase from about 60?? to 340??C. These Ro data plotted against temperature fall along an exponential curve with a coefficient of determination of about 0.8. Other boreholes sampled in the field show similar relationships. A regression curve calculated for temperature and Ro in borehole M-105 correctly predicts temperatures in other boreholes within the central portion of the geothermal system. The correlation between the reflectance values and logged temperature, together with consistent temperature estimates from fluid inclusion and oxygen isotope geothermometry, indicates that changes in Ro are an accurate and sensitive recorder of the maximum temperature attained. Therefore, vitrinite reflectance can be used in this geothermal system to predict the undisturbed temperature in a geothermal borehole during drilling before it regains thermal equilibrium. Although existing theoretical functions which relate Ro to temperature and duration of heating are inaccurate, empirical temperature-Ro curves are still useful for geothermometry. A comparison of temperature-Ro regression curves derived from nine boreholes within the Cerro Prieto system suggests that heating across the central portion of the field occurred penecontemporaneously, but varies near margins. Boreholes M-93 and M-94 appear to have cooled from their maximum temperatures, whereas M-3 and Prian-1 have only recently been heated. Comparison of the temperature-Ro data from the Salton Sea, California, geothermal system indicates that the duration of heating has been longer there than at the Cerro Prieto field. ?? 1981.

  9. Cerro Papayo: an astronomical, calendrical and traditional landmark in Ancient Mexico.

    Science.gov (United States)

    Galindo Trejo, J.; Aguilera, T.; Montero García, I. A.

    Cerro Papayo is a peculiar formed hill (almost perfect semisphere, 3,630 m) situated at the east side of the Valley of Mexico. According to surface reconnaissance there is on its cusp a prehispanic site and a modern shrine dedicated to the Virgin of Guadalupe. Its striking appearance and its unobstructed visibility from anyplace in the Valley were used, since preclassic up to postclassic periods, to mark at sunrise the moment of precise astronomical, calendrical and traditional events. The present work shows observational evidence from Cuicuilco, the Templo Mayor of Tenochtitlan and Tepeyacac.

  10. Numerical modeling of high-temperature deep wells in the Cerro Prieto geothermal field, Mexico

    OpenAIRE

    García, A.; F. Ascencio; Espinosa, G.; E. Santoyo; H. Gutiérrez; V. Arellano

    1999-01-01

    A numerical modeling study of three non-producing deep geothermal wells from Cerro Prieto is presented. We compute the expected production characteristics of these wells in order to determine if their inability to sustain flow was due to (i) heat loss effects in the well, (ii) the influence of production casing diameters, (iii) the transient heat loss during the first few days of well discharge, or (iv) the effect of secondary low-enthalpy inflows. A new version of the wellbore flow simulator...

  11. Two-dimensional modeling of apparent resistivity pseudosections in the Cerro Prieto region

    Energy Technology Data Exchange (ETDEWEB)

    Vega, R.; Martinez, M.

    1981-01-01

    Using a finite-difference program (Dey, 1976) for two-dimensional modeling of apparent resistivity pseudosections obtained by different measuring arrays, four apparent resistivity pseudosections obtained at Cerro Prieto with a Schlumberger array by CFE personnel were modeled (Razo, 1978). Using geologic (Puente and de la Pena, 1978) and lithologic (Diaz, et al., 1981) data from the geothermal region, models were obtained which show clearly that, for the actual resistivity present in the zone, the information contained in the measured pseudosections is primarily due to the near-surface structure and does not show either the presence of the geothermal reservoir or the granitic basement which underlies it.

  12. Goldgroup矿业公司Cerro Prieto金矿投入商业化生产

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Goldgroup矿业公司(Goldgroup Mining Inc.)日前宣布,公司所属墨西哥Sonora地区Cerro Prieto金矿从6月1日起正式投入商业化生产。此前从2013年12月起该金矿就一直在进行小规模中试,预计2016年该金矿黄金产量将达到15000盎司。

  13. Overview of the Mexican-American cooperative program at the Cerro Prieto geothermal field

    Science.gov (United States)

    Lippmann, M. J.; Zelwer, R.

    1982-09-01

    The Lawrence Berkeley Laboratory is coordinating the US technical activities being carried out at Cerro Prieto under a five-year agreement between the US Department of Energy and the Comission Federal de Electricidad de Mexico. This agreement, signed in July 1977, is expected to expire in July 1982. Efforts are being made to continue some of the research beyond the formal termination of the agreement. A description of the program, which involves studies of geology, geophysics, hydrodynamics, subsidence, geothermal wells and reservoirs, and aquifers, is discussed.

  14. Preliminary plasma spectrometric analyses for selected elements in some geothermal waters from Cerro Prieto, Mexico

    Science.gov (United States)

    Ball, J.W.; Jenne, E.A.

    1983-01-01

    As part of a cooperative study with Dr. Alfred Truesdell, water samples collected from geothermal power production wells at Cerro Prieto, Mexico, were analyzed for selected elements by d.c. argon plasma emission spectroscopy. Spectral interferences due to the presence of high concentrations of Ca, Si, Na and K in these water affected the apparent concentration values obtained. These effects were evaluated and correction techniques were developed and applied to the analytical values. Precipitates present in the samples at the time of analysis adversely affected the accuracy, precision and interpretability of the data. (USGS)

  15. 222Radon Concentration Measurements biased to Cerro Prieto Fault for Verify its Continuity to the Northwest of the Mexicali Valley.

    Science.gov (United States)

    Lazaro-Mancilla, O.; Lopez, D. L.; Reyes-Lopez, J. A.; Carreón-Diazconti, C.; Ramirez-Hernandez, J.

    2009-05-01

    The need to know the exact location in the field of the fault traces in Mexicali has been an important affair due that the topography in this valley is almost flat and fault traces are hidden by plow zone, for this reason, the southern and northern ends of the San Jacinto and Cerro Prieto fault zones, respectively, are not well defined beneath the thick sequence of late Holocene Lake Cahuilla deposits. The purpose of this study was to verify if Cerro Prieto fault is the continuation to the southeast of the San Jacinto Fault proposed by Hogan in 2002 who based his analysis on pre-agriculture geomorphy, relocation and analysis of regional microseismicity, and trench exposures from a paleoseismic site in Laguna Xochimilco, Mexicali. In this study, four radon (222Rn) profiles were carried out in the Mexicali Valley, first, to the SW-NE of Cerro Prieto Volcano, second, to the W-E along the highway Libramiento San Luis Río Colorado-Tecate, third, to the W-E of Laguna Xochimilco and fourth, to the W-E of the Colonia Progreso. The Radon results allow us to identify in the Cerro Prieto profile four regions where the values exceed 100 picocuries per liter (pCi/L), these regions can be associated to fault traces, one of them associated to the Cerro Prieto Fault (200 pCi/L) and other related with Michoacán de Ocampo Fault (450 pCi/L). The profile Libramiento San Luis Río Colorado-Tecate, show three regions above 100 pCi/L, two of them related to the same faults. In spite of the results of the Laguna Xochimilco, site used by Hogan (2002), the profile permit us observe three regions above the 100 pCi/L, but we can associate only one of the regions above this level to the Michoacán de Ocampo Fault, but none region to the Cerro Prieto Fault. Finally in spite of the Colonia Progreso is the shortest profile with only five stations, it shows one region with a value of 270 pCi/L that we can correlate with the Cerro Prieto Fault. The results of this study allow us to think in the

  16. A first shallow firn-core record from Glaciar La Ollada, Cerro Mercedario, central Argentine Andes

    Science.gov (United States)

    Bolius, David; Schwikowski, Margit; Jenk, Theo; Gäggeler, Heinz W.; Casassa, Gino; Rivera, Andrés

    In January 2003, shallow firn cores were recovered from Glaciar Esmeralda on Cerro del Plomo (33°14‧ S, 70°13‧ W; 5300 ma.s.l.), central Chile, and from Glaciar La Ollada on Cerro Mercedario (31°58‧ S, 70°07‧ W; 6070 ma.s.l.), Argentina, in order to find a suitable archive for paleoclimate reconstruction in a region strongly influenced by the El Niño-Southern Oscillation. In the area between 28° S and 35° S, the amount of winter precipitation is significantly correlated to the Southern Oscillation Index, with higher values during El Niño years. Glaciochemical analysis indicates that the paleo-record at Glaciar La Ollada is well preserved, whereas at Glaciar Esmeralda the record is strongly influenced by meltwater formation and percolation. A preliminary dating of the Mercedario core by annual-layer counting results in a time-span of 17 years (1986-2002), yielding an average annual net accumulation of 0.45 m w.e.

  17. Optical Sky Brightness at Cerro Tololo Inter-American Observatory from 1992 to 2006

    CERN Document Server

    Krisciunas, Kevin; Sanhueza, Pedro; Schwarz, Hugo E; Semler, Dylan R; Suntzeff, Nicholas B; Vera, Sergio

    2007-01-01

    We present optical UBVRI sky brightness measures from 1992 through 2006. The data are based on CCD imagery obtained with the CTIO 0.9-m, 1.3-m, and 1.5-m telescopes. The B- and V-band data are in reasonable agreement with measurements previously made at Mauna Kea, though on the basis of a small number of images per year there are discrepancies for the years 1992 through 1994. Our CCD-based data are not significantly different than values obtained at Cerro Paranal. We find that the yearly averages of V-band sky brightness are best correlated with the 10.7-cm solar flux taken 5 days prior to the sky brightness measures. This implies an average speed of 350 km/sec for the solar wind. While we can measure an enhancement of the night sky levels over La Serena 10 degrees above the horizon, at elevation angles above 45 degrees we find no evidence that the night sky brightness at Cerro Tololo is affected by artificial light of nearby towns and cities.

  18. Cerro de Pasco and other massive sulfide deposits of central Peru

    Energy Technology Data Exchange (ETDEWEB)

    Cheney, E.S.

    1985-01-01

    The famous Cerro de Pasco Pb-Zn-Ag deposit historically has been considered to be hydrothermally derived from an adjacent Tertiary volcanic vent. However, texturally massive pyrite-chert and pyrite-sphalerite-galena in the deposit have the same strike and cross folds as the adjacent pre-Tertiary strata. Both the deposit and the strata are cut by one of the large Longitudinal Faults. Both dikes and pyrite-enargite veins associated with the vent cut the massive sulfides; fragments of massive pyrite occur in the vent. A few examples of laminated pyrite and chert, banded pyrite and chert, banded pyrite and sphalerite, and banded pyrite, sphalerite, and galena are preserved in the massive sulfide portion of the deposit. The deposit has the composition and zoning patterns typical of shale-hosted massive sulfides. Cerro de Pasco probably in part of the pelitic Devonian Excelsior formation. The Colquijirca deposit 8 km to the south and the San Cristobal district 110 km to the south likewise have been considered to be Tertiary volcanic hydrothermal deposits. Colquijirca consists of stratigraphically controlled mantos of layered pyrite, chert and tuff in the Tertiary Calera formation. The mantos of the San Cristobal district are along the upper contact of the pyritic, Permian, Catalina felsic volcanic rocks; some ore consists of laminated pyrite and sphalerite. Tertiary plutons are conspicuously absent at San Cristobal, and the ores are brecciated by Tertiary folding.

  19. Reservoir Simulation on the Cerro Prieto Geothermal Field: A Continuing Study

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda, M.; Marquez, R.; Arellano, V.; Esquer, C.A.

    1983-12-15

    The Cerro Prieto geothermal field is a liquid-dominated geothermal reservoir of complex geological and hydrological structure. It is located at the southern end of the Salton-Mexicali trough which includes other geothermal anomalies as Heber and East Mesa. Although in 1973, the initial power plant installed capacity was 75 MW of electrical power, this amount increased to 180 MW in 1981 as field development continued. It is expected to have a generating capacity of 620 MW by the end of 1985, when two new plants will be completely in operation. Questions about field deliverability, reservoir life and ultimate recovery related to planned installations are being presently asked. Numerical modeling studies can give very valuable answers to these questions, even at the early stages in the development of a field. An effort to simulate the Cerro Prieto geothermal reservoir has been undergoing for almost two years. A joint project among Comision Federal de Electricidad (CFE), Instituto de Investigaciones Electricas (IIE) and Intercomp of Houstin, Texas, was created to perform reservoir engineering and simulation studies on this field. The final project objective is tosimulate the behavior of the old field region when production from additional wells located in the undeveloped field zones will be used for feeding the new power plants.

  20. Analysis of heavy oils: Method development and application to Cerro Negro heavy petroleum

    Energy Technology Data Exchange (ETDEWEB)

    Carbognani, L.; Hazos, M.; Sanchez, V. (INTEVEP, Filial de Petroleos de Venezuela, SA, Caracas (Venezuela)); Green, J.A.; Green, J.B.; Grigsby, R.D.; Pearson, C.D.; Reynolds, J.W.; Shay, J.Y.; Sturm, G.P. Jr.; Thomson, J.S.; Vogh, J.W.; Vrana, R.P.; Yu, S.K.T.; Diehl, B.H.; Grizzle, P.L.; Hirsch, D.E; Hornung, K.W.; Tang, S.Y.

    1989-12-01

    On March 6, 1980, the US Department of Energy (DOE) and the Ministry of Energy and Mines of Venezuela (MEMV) entered into a joint agreement which included analysis of heavy crude oils from the Venezuelan Orinoco oil belt.The purpose of this report is to present compositional data and describe new analytical methods obtained from work on the Cerro Negro Orinoco belt crude oil since 1980. Most of the chapters focus on the methods rather than the resulting data on Cerro Negro oil, and results from other oils obtained during the verification of the method are included. In addition, published work on analysis of heavy oils, tar sand bitumens, and like materials is reviewed, and the overall state of the art in analytical methodology for heavy fossil liquids is assessed. The various phases of the work included: distillation and determination of routine'' physical/chemical properties (Chapter 1); preliminary separation of >200{degree}C distillates and the residue into acid, base, neutral, saturated hydrocarbon and neutral-aromatic concentrates (Chapter 2); further separation of acid, base, and neutral concentrates into subtypes (Chapters 3-5); and determination of the distribution of metal-containing compounds in all fractions (Chapter 6).

  1. Elemental analysis of pottery from Cerro de las Ventanas, Zacatecas, by INAA

    Energy Technology Data Exchange (ETDEWEB)

    Lopez del Rio, H.; Mireles G, F. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Mendez C, R. Y. [Universidad Autonoma de Zacatecas, Unidad Academica de Antropologia, Apdo. Postal 555 Suc. C, Zacatecas (Mexico); Nicolas C, M. [Universidad Autonoma de San Luis Potosi, Coordinacion de Ciencias Sociales y Humanidades, Av. Industrias 101-A, Fracc. Talleres, 78494 San Luis Potosi (Mexico); Speakman, R. J. [Museum Conservation Institute, Smithsonian Institution, Suitland, 20746 Maryland (United States); Glascock, M. D. [Reactor Center, University of Missouri, Columbia, 65211 Missouri (United States)

    2009-10-15

    Fifteen ceramic fragments samples from Cerro de las Ventanas site, Zacatecas, were analyzed by instrumental neutron activation analysis. Thirty-two elements were measured: Al, As, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Ti, Th, U, V, Yb, Zn, and Zr. Cluster analysis and principal component analysis were performed on the dataset to examine similarities between samples and to establish compositional groups. The statistical analyses of the dataset suggest that the pottery samples form a unique chemically homogeneous group, with the exception of one pottery sample. The compositional data were compared to an existing Meso american ceramic database. It was found that the newly generated data fit best with data from a previous chemical analysis of pottery from the Mal paso Valley. However, despite the apparent similarity, pottery samples from the site of Cerro de las Ventanas represent a new and unique chemical fingerprint in the region. (Author)

  2. SITE CHARACTERISTICS OF THE SUMMIT OF CERRO CHAJNANTOR AT THE 5640 M ALTITUDE

    Directory of Open Access Journals (Sweden)

    K. Motohara

    2011-01-01

    Full Text Available Instituto de Astronomía de la Universidad de Tokio está promoviendo el proyecto TAO (University of Tokyo Atacama Observatory; Yoshii et al. 2010 para construir un telescopio infrarrojo en la cima de Cerro Chajnantor (altitud 5640 m en el desierto de Atacama en el Norte de Chile. Para la evaluación de las características del sitio, primero se realizó el monitoreo del tiempo atmosférico, la emisividad de nubes y el seeing durante 2006. 2007. La fracción despejada fue alta (>80% y la mediana del seeing en la banda V fue de tan solo 0."69. Un telescopio explorador de 1 m llamado miniTAO fue instalado y comenzó a observar en 2009. Con éste se han obtenido imágenes satisfactorias de Paα de hidrógeno 1.875 μm como también imágenes de 30.40 μm por primera vez desde un telescopio en tierra. Estos resultados demuestran que la cima de Cerro Chajnantor es uno de los mejores sitios para la astronomía infrarroja en la Tierra.

  3. Cerro Negro field, Venezuela: geological images from a high resolution 3-D survey

    Energy Technology Data Exchange (ETDEWEB)

    Woller, Kevin L. [Mobil Technology Co. (WEC)

    1999-07-01

    Following a pilot 3-D survey, Petrolera Cerro Negro acquired and processed a 3-D dynamite survey over the Cerro Negro Field in Venezuela. We designed the survey to achieve high frequency imaging at the relatively shallow (< 1000 m) objectives in the Morichal formation. The data exhibits usable frequencies in the 10-120 Hz range after migration. The results of the survey have satisfied the original objective of imaging the faults and basement structure in the field. Use of continuity measurements on the data has resulted in a photographic quality image of the faults at the basement level. The pattern of the faults indicates an unexpected degree of complexity, indicating a richer structural history than originally thought. The continuity data also shows depositional details in the Morichal, which in accordance with geological history of the area. The operatorship is currently in the process of drilling many horizontal development wells. The patterns of the wells bores and variations in the rock types present a challenge to the usage of the 3-D seismic. The operatorship is working to raise the understanding and utility of the seismic data to another plateau. (author)

  4. Presence of cross flow in the Cerro Prieto geothermal field, BC; Presencia de flujo cruzado en el campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez, Marco Helio [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, Baja California (Mexico)]. E-mail: marco.rodriguez01@cfe.gob.mx

    2011-01-15

    During the development of Cerro Prieto geothermal field, BC, exploitation has increased gradually, causing a continuous drop in pressure to almost 100 bars in the central and eastern parts of the field. This has occurred despite the high natural recharge induced by the reservoir exploitation and helped by the high permeability of the reservoir and the wide availability of natural recharge of low-temperature water in the vicinity. The strata above the production zones have significantly lower temperatures than these zones, but due to the particular characteristics of the reservoir, do not have pressure drops. As the pressure of producing strata declines, the hydraulic pressure differential between them and the overlying strata increases. Thus in recent years the phenomenon of cross flow occurs with greater frequency and severity. In this paper, this phenomenon is analyzed, detailing the specific mechanisms favoring it and identifying the stage (drilling or workover) in which it commonly occurs. Rigorous supervision during these stages is crucial to identifying cross flow and to taking necessary measures to save the well. Cross flow cases are presented at different stages in the history of a well: during drilling, repair, before and during the stimulation, and during production. [Spanish] Durante el desarrollo del campo geotermico de Cerro Prieto, BC, la explotacion se ha incrementado en forma gradual provocando una continua caida de presion, que en las porciones central y oriente ha sido de casi 100 bars. Esto ha ocurrido a pesar de la enorme recarga natural inducida por la explotacion, favorecida por la alta permeabilidad del yacimiento y la gran disponibilidad de recarga natural de agua de baja temperatura en los alrededores del mismo. Los estratos ubicados encima de las zonas productoras presentan temperaturas significativamente menores que estos, pero debido a las caracteristicas particulares del yacimiento, no han presentado abatimiento en su presion. En la

  5. Minimal thermodynamic conditions in the reservoir to produce steam at the Cerro Prieto geothermal field, BC; Condiciones termodinamicas minimas del yacimiento para producir vapor en el campo geotermico de Cerro Prieto, B.C.

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez; Marco Helio [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, Baja California (Mexico)]. E-mail: marco.rodriguez01@cfe.gob.mx

    2009-01-15

    Minimal thermodynamic conditions in the Cerro Prieto geothermal reservoir for steam production are defined, taking into account the minimal acceptable steam production at the surface, considering a rank of mixed-enthalpies for different well-depths, and allowing proper assessments for the impacts of the changes in fluid reservoir pressure and enthalpy. Factors able to influence steam production are discussed. They have to be considered when deciding whether or not to drill or repair a well in a particular area of the reservoir. These evaluations become much more relevant by considering the huge thermodynamic changes that have occurred at the Cerro Prieto geothermal reservoir from its development, starting in 1973, which has lead to abandoning some steam producing areas in the field. [Spanish] Las condiciones termodinamicas minimas del yacimiento geotermico de Cerro Prieto, BC, para producir vapor se determinan tomando en cuenta la minima produccion de vapor aceptable en superficie, considerando un rango de entalpias de la mezcla y para diferentes profundidades de pozos, lo que permite valorar adecuadamente el impacto de la evolucion de la presion y entalpia del fluido en el yacimiento. Se discuten los factores que pueden afectar la produccion de vapor, los cuales se deben tomar en cuenta para determinar la conveniencia o no de perforar o reparar un pozo en determinada zona del yacimiento. Estas evaluaciones adquieren gran relevancia al considerar los enormes cambios termodinamicos que ha presentado el yacimiento geotermico de Cerro Prieto, como resultado de su explotacion iniciada en 1973, lo que ha llevado a abandonar algunas zonas del campo para la produccion de vapor. Palabras Clave: Cerro Prieto, entalpia, evaluacion de yacimientos, politicas de explotacion, presion, produccion de vapor.

  6. Extension of the Cerro Prieto field and zones in the Mexicali Valley with geothermal possibilities in the future

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca L, H.L.; de la Pena L, A.; Puente C, I.; Diaz C, E.

    1981-01-01

    This study concerns the possible extension of the Cerro Prieto field and identification of other zones in the Mexicali Valley with geothermal development potential by assessing the structural geologic conditions in relation to the regional tectonic framework and the integration of geologic and geophysical surveys carried out at Cerro Prieto. This study is based on data obtained from the wells drilled to date and the available geological and geophysical information. With this information, a geologic model of the field is developed as a general description of the geometry of what might be the geothermal reservoir of the Cerro Prieto field. In areas with geothermal potential within the Mexicali Valley, the location of irrigation wells with anomalous temperatures was taken as a point of departure for subsequent studies. Based on this initial information, gravity and magnetic surveys were made, followed by seismic reflection and refraction surveys and the drilling of 1200-m-deep multiple-use wells. Based on the results of the final integration of these studies with the geology of the region, it is suggested that the following areas should be explored further: east of Cerro Prieto, Tulecheck, Riito, Aeropuerto-Algodones, and San Luis Rio Colorado, Sonora.

  7. ENTIERROS Y OFRENDAS: PRÁCTICAS MORTUORIAS, AGRÍCOLAS Y CULINARIAS EN LOS SIGLOS XIII Y XIV EN TINOGASTA (CATAMARCA, ARGENTINA

    Directory of Open Access Journals (Sweden)

    Norma Ratto

    2014-01-01

    Full Text Available En este trabajo se presentan los análisis realizados sobre las asociaciones arqueobotánicas recupera - das en dos contextos funerarios del oeste de Tinogasta (Catamarca, Argentina. Los sitios Las Champas y Bebé de La Troya presentan macrorrestos vegetales junto a inhumaciones que permiten indagar el rol de dichos restos y sus implicancias dentro de las sociedades tardías catamarqueñas. Nuestro objetivo es caracterizar las prácticas sociales que intervinieron en el depósito de restos de plantas como acom - pañamiento funerario, al identificar la presencia de marcas diagnósticas de procesamiento culinario en dichos restos, que además son identificados taxonómicamente. En ambos sitios tanto los macrorrestos como los sedimentos asociados fueron analizados a ojo desnudo, lupa binocular y microscopio óptico. Las muestras fueron identificadas taxonómicamente siguiendo la descripción de caracteres diagnósticos botánicos y etnoarqueológicos para prácticas de procesamiento. En el sitio Las Champas se recuperaron semillas de Cucurbita aff. maxima subsp. maxima y Chenopodium quinoa var. melanospermum con rasgos de procesamiento, como así también un artefacto confeccionado sobre Lagenaria siceraria . Los análisis microscópicos dieron por resultado la presencia de gramíneas y cf. Zea mays . En Bebé de la Tro - ya se identificaron también semillas de Cucurbita aff. maxima subsp. maxima y endocarpos de Prosopis sp., sin marcas de procesamiento. Los resultados obtenidos permiten sugerir la presencia de restos de plantas como simientes, comidas y vestimenta, formando parte del contexto funerario. Estas tres formas de depósito vegetal demuestran prácticas intencionales diferentes durante las inhumaciones como así también permiten indagar en el aspecto culinario y agrario de las sociedades tardías catamarqueñas.

  8. Geología de la región del Cerro Guanaquero, Río Diamante, Mendoza Geology of Cerro Guanaquero region, Diamante River, Mendoza

    Directory of Open Access Journals (Sweden)

    Federico Fuentes

    2008-03-01

    Full Text Available El estudio realizado presenta nuevos datos sobre un sector poco conocido de la Cordillera Principal de Mendoza, en la alta cuenca del río Diamante en las adyacencias del cerro Guanaquero, y los primeros datos geocronológicos de sus rocas volcánicas. Las unidades geológicas presentes en el área se dividen en cuatro grupos principales: secuencias sedimentarias mesozoicas marinas y continentales intensamente plegadas y falladas; intrusivos y volcanitas intermedias de edad neógena; rocas volcánicas pliocenas a recientes de composición intermedia a básica, y depósitos cuaternarios inconsolidados. El cerro Guanaquero, un estratovolcán pliocuaternario intensamente erosionado por glaciares pleistocenos, con sus 4.841 metros es el rasgo orográfico más prominente. Está constituido esencialmente por andesitas grises porfíricas, piroxénicas a biotíticas. Intercaladas con las coladas andesíticas se presentan depósitos piroclásticos, aglomerados volcánicos, ignimbritas y basaltos. La datación de una andesita por el método K-Ar en roca total arrojó una edad de 1,4 ± 0,1 Ma. La deformación ándica comenzó en forma de una faja plegada y corrida de piel fina, con pliegues por despegue en el sector occidental y por propagación de falla en el oriental. La compresión al oeste de los 69º47´O terminó por invertir la fallas normales del rift mesozoico. A lo largo de este meridiano se encuentra la falla más importante de la región, la que se ha correlacionado con la falla Malargüe, bien desarrollada en latitudes más australes. Esta falla limita la faja plegada y corrida del Aconcagua, de naturaleza epidérmica, y la faja plegada y corrida de Malargüe, controlada por la inversión tectónica del basamento. El volcanismo fue muy intenso en el Plioceno y el Cuaternario, correspondiendo a un período de empinamiento de la placa oceánica subducida, en el que la región ha sido levantada pasivamente. La alta resistencia a la erosión de

  9. Microfaunal evidence of age and depositional environments of the Cerro Prieto section (Plio-Pleistocene), Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ingle, J.C. Jr.

    1982-01-01

    Microfossils including benthic and planktic foraminifera, ostracodes, calcareous algae, fish skeletal material, and fragments of pelecypods were found in 14 core samples from depths of 185 to 1952 m in the Cerro Prieto geothermal field, providing evidence of both the age and depositional history of sediments comprising the 3000-m-thick Pliocene and Pleistocene section in this area. Ostracodes of brackish water and marine origin constitute the most common microfossils present in this sequence occurring in 8 samples; in situ littoral and neritic species of benthic foraminifera occur in 5 samples with planktic species present in 2 samples. Distributional patterns of ostracodes and foraminifera together with previously analyzed lithofacies (Lyons and van de Kamp, 1980) indicate that the Cerro Prieto section represents an intertonguing complex of alluvial, deltaic, estuarine, and shallow marine environments deposited along the front of the Colorado River delta as it prograded across the Salton Trough during Pliocene and Pleistocene time. Foraminiferal evidence indicates that a sand and shale unit commonly present at depths between 700 and 1100 m represents a significant mid-Pleistocene marine incursion in the Cerro Prieto area. Tentative correlation of the Cerro Prieto section with the well dated Palm Springs Formation of the Imperial Valley, California area suggests that the Pliocene/Pleistocene boundary occurs at a depth of approximately 2000 m in the area of well M-93. Reworked specimens of Cretaceous foraminifera and fragments of the Cretaceous pelecypod Inoceramus were found in five samples further substantiating the Colorado Plateau provenance of a significant portion of the Colorado River deltaic sediments in the Cerro Prieto area.

  10. Arterial oxygen saturation in healthy newborns delivered at term in Cerro de Pasco (4340 m and Lima (150 m

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    Gonzales Gustavo F

    2005-09-01

    Full Text Available Abstract Background High altitude is associated with both low pulse oxygen saturation at birth and more pre-term deliveries. The present study was performed to determine pulse oxygen saturation in newborns at term in Cerro de Pasco (4340 m and Lima (150 m to test the hypothesis that low pulse oxygen saturation at birth at high altitudes was not observed at term deliveries. Methods The present study was designed to determine pulse oxygen saturation values through 1 minute to 24 hours and values of Apgar score at 1 and 5 minutes in newborns delivered at term in Cerro de Pasco (4340 m and Lima (150 m. Pulse oxygen saturation was recorded in 39 newborns from Cerro de Pasco (4340 m and 131 from Lima (150 m at 1, 2, 3, 4, 5, 10, 15, 30 minutes and 1, 2, 8 and 24 hours after delivery. Apgar score was assessed at 1 and 5 minutes after birth. Neurological score was assessed at 24 h of birth by Dubowitz exam. Results Pulse oxygen saturation increased significantly from 1 to 15 min after birth at sea level and from 1 to 30 minutes at Cerro de Pasco. Thereafter, it increased slightly such that at 30 min at sea level and at 60 minutes in Cerro de Pasco it reached a plateau up to 24 hours after birth. At all times, pulse oxygen saturation was significantly higher at sea level than at high altitude (P Conclusion From these analyses may be concluded that pulse oxygen saturation at 4340 m was significantly low despite the fact that births occurred at term. Apgar scores at first minute and neurological scores were also lower at high altitudes.

  11. Cálculo del número mínimo de vasijas y recolección superficial: criterios metodológicos y análisis de casos del oeste tinogasteño (Catamarca

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    Anabel Feely

    2013-01-01

    Full Text Available El trabajo es de neto corte metodológico siendo su objetivo presentar un procedimiento analítico para la construcción de la unidad número mínimo de vasijas y para la realización de muestreos en áreas con abundante material cerámico superficial. La articulación de ambos procedimientos permite tanto obtener información confiable a nivel interpretativo como reducir el volumen de material recolectado. Ejemplificamos mediante casos de estudio provenientes de sitios del oeste tinogasteño (Catamarca los errores interpretativos a los que puede conducir el uso de frecuencias de fragmentos en el análisis de los conjuntos cerámicos; como así también ponemos en evidencia la cantidad innecesaria de material superficial que puede recolectarse cuando no median criterios de selección de las muestras.

  12. Hydrothermal alteration of sediments associated with surface emissions from the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Valette-Silver, J.N.; Esquer P., I.; Elders, W.A.; Collier, P.C.; Hoagland, J.R.

    1981-01-01

    A study of the mineralogical changes associated with these hydrothermal vents was initiated with the aim of developing possible exploration tools for geothermal resources. The Cerro Prieto reservoir has already been explored by extensive deep drilling so that relationships between surface manifestations and deeper hydrothermal processes could be established directly. Approximately 120 samples of surface sediments were collected both inside and outside of the vents. The mineralogy of the altered sediments studied appears to be controlled by the type of emission. A comparison between the changes in mineralogy due to low temperature hydrothermal activity in the reservoir, seen in samples from boreholes, and mineralogical changes in the surface emission samples shows similar general trends below 180 C: increase of quartz, feldspar and illite, with subsequent disappearance of kaolinite, montmorillonite, calcite and dolomite. These mineral assemblages seem to be characteristic products of the discharge from high intensity geothermal fields.

  13. Comments on some of the drilling and completion problems in Cerro Prieto geothermal wells

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez A, B.; Sanchez G, G.

    1981-01-01

    From 1960 to the present, 85 wells with a total drilling length exceeding 160,000 m have been constructed at Cerro Prieto, a modest figure compared to an oil field. This activity took place in five stages, each characterized by changes and modifications required by various drilling and well-completion problems. Initially, the technical procedures followed were similar to those used in the oil industry. However, several problems emerged as a result of the relatively high temperatures found in the geothermal reservoir. The various problems that have been encountered can be considered to be related to drilling fluids, cements and cementing operations, lithology, geothermal fluid characteristics, and casings and their accessories. As the importance of high temperatures and the characteristics of the geothermal reservoir fluids were better understood, the criteria were modified to optimize well-completion operations, and satisfactory results have been achieved to date.

  14. Isotopic changes in the fluids of the Cerro Prieto {Beta} Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Mahendra; Quijano, Luis; Gutierrez, Hector; Iglesias, Eduardo; Truesdell, Alfred

    1996-01-24

    Monitoring changes with time of the isotopes of water (18O and D) in wellhead fluids is an effective way of indicating reservoir changes and processes. Because 18O concentrations in water are altered by high-temperature exchange with rock oxygen and because both 18O and D are fractionated in vapor-liquid separation processes at the surface (separators and cooling towers), these isotopes are excellent indicators of inflow and distribution of fluids from outside the reservoir, either natural or injected. Studies of the isotopic compositions of fluids from the Cerro Prieto field in Baja California, Mexico show that pressure drawdown in the major β (beta) reservoir has caused intense boiling followed by inflow of water from outside the reservoir. A method of field exploitation based on this behavior is discussed.

  15. Dynamics of a geothermal field traced by noble gases: Cerro Prieto, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Mazor, E. (Weizmann Inst. of Science, Rehovot, Israel); Truesdell, A.H.

    1981-01-01

    Noble gases have been measured mass spectrometrically in samples collected during 1977 from producing wells at Cerro Prieto. Positive correlations between concentrations of radiogenic (He, /sup 40/Ar) and atmospheric noble gases (Ne, Ar, and Kr) suggest the following dynamic model: the geothermal fluids originated from meteoric water penetrated to more than 2500 m depth (below the level of first boiling) and mixed with radiogenic helium and argon-40 formed in the aquifer rocks. Subsequently, small amounts of steam were lost by a Raleigh process (0 to 3%) and mixing with shallow cold water occurred (0 to 30%). Noble gases are sensitive tracers of boiling in the initial stages of 0 to 3% steam separation and complement other tracers, such as Cl or temperature, which are effective only beyond this range.

  16. BESO échelle spectroscopy of solar-type stars at Cerro Armazones

    Science.gov (United States)

    Fuhrmann, K.; Chini, R.; Hoffmeister, V. H.; Lemke, R.; Murphy, M.; Seifert, W.; Stahl, O.

    2011-03-01

    The Bochum Échelle Spectroscopic Observer BESO is a fibre-fed high-resolution spectrograph for the 1.5-m Hexapod Telescope at the Cerro Armazones Observatory in the Atacama desert in Chile. Here we report on the first BESO observations and model atmosphere analyses of solar-type stars secured in 2010 April. The quality of the data is first tested with a reflected sunlight spectrum as well as the standard G-type subgiant 70 Vir. We then investigate the bright and supposedly single F-type star ξ Gem and present the spectroscopic evidence that instead favours an equal-mass binary. We present also the first composite synthetic modelling of the G-type visual binary HR 3430 and discuss the spectroscopic observations that identify this as a triple system. We conclude with another triple, the famous and very nearby α Cen, and the basic stellar parameters of its inner, solar-type visual binary.

  17. Bottom Topography, Recent Sedimentation and Water Volume of the Cerro Prieto Dam, NE Mexico

    Science.gov (United States)

    Yutsis, V. V.

    2012-12-01

    Cerro Prieto dam, relatively small water reservoir in the NE of Mexico, is characterized by a very high velocity of recent sedimentation, irregular bottom topography and sub-bottom seepage. Very high resolution seismic study using non-linear parametric echo sounder SES-2000 was carried out in this water reservoir, which is one of the main resources of potable water for the Monterrey, the city with a population of about four million inhabitants. A strong difference between water depth and hence the volume capacity calculated by National Commission of Water (Comision Nacional del Agua, CNA), Digital Elevation Model (DEM), and acoustic data was discovered. Very high rate of recent sedimentation due to damming is discussed. SES data interpretation shows that the thickness of recent sediments due to siltation of the reservoir reaches 3.5-4.0 m. Differences between the CNA and SES data indicate storage losses from 8-10 up to 30 million cubic meters due to sedimentation.

  18. Did stresses from the Cerro Prieto Geothermal Field influence the El Mayor-Cucapah rupture sequence?

    Science.gov (United States)

    Trugman, Daniel T.; Borsa, Adrian A.; Sandwell, David T.

    2014-12-01

    The Mw 7.2 El Mayor-Cucapah (EMC) earthquake ruptured a complex fault system in northern Baja California that was previously considered inactive. The Cerro Prieto Geothermal Field (CPGF), site of the world's second largest geothermal power plant, is located approximately 15 km to the northeast of the EMC hypocenter. We investigate whether anthropogenic fluid extraction at the CPGF caused a significant perturbation to the stress field in the EMC rupture zone. We use Advanced Land Observing Satellite interferometric synthetic aperture radar data to develop a laterally heterogeneous model of fluid extraction at the CPGF and estimate that this extraction generates positive Coulomb stressing rates of order 15 kPa/yr near the EMC hypocenter, a value which exceeds the local tectonic stressing rate. Although we cannot definitively conclude that production at the CPGF triggered the EMC earthquake, its influence on the local stress field is substantial and should not be neglected in local seismic hazard assessments.

  19. Lithology and hydrothermal alteration determination from well logs for the Cerro Prieto Wells, Mexico

    Science.gov (United States)

    Ershaghi, I.; Ghaemian, S.; Abdassah, D.

    1981-10-01

    The characteristics of geophysical well logs are compared against the sand-shale series of the sedimentary column of the Cerro Prieto Geothermal Field, Mexico. It is shown that the changes in mineralogy of the rocks because of hydrothermal alteration are not easily detectable on the existing logs. However, if the behavior of clay minerals alone is monitored, the onset of the hydrothermally altered zones may be estimated from the well logs. The effective concentration of clay-exchange cations, Q/sub v/, is computed using the data available from conventional well logs. Zones indicating the disappearance of low temperature clays are considered hydrothermally altered formations with moderate to high permeability and temperature, and suitable for completion purposes.

  20. Dynamics of a geothermal field traced by noble gases: Cerro Prieto, Mexico

    Science.gov (United States)

    Mazor, E.; Truesdell, A.H.

    1984-01-01

    Noble gases have been measured mass spectrometrically in samples collected during 1977 from producing wells at Cerro Prieto. Positive correlations between concentrations of radiogenic (He and 40Ar) and atmospheric noble gases (Ne, Ar and Kr) suggest the following dynamic model: the geothermal fluids originated from meteoric water that penetrated to more than 2500 m depth (below the level of first boiling) and mixed with radiogenic He and 40Ar formed in the aquifer rocks. Subsequently, small amounts of steam were lost by a Raleigh process (0 - 30%) and mixing with shallow cold water occurred (0 - 30%). Noble gases are sensitive tracers of boiling in the initial stages of 0 - 3% steam separation and complement other tracers, such as C1 or temperature, which are effective only beyond this range. ?? 1984.

  1. Study of the atmospheric conditions at Cerro Armazones using astronomical data

    CERN Document Server

    Lakicevic, Masha; Noll, Stefan; Kausch, Wolfgang; Unterguggenberger, Stefanie; Kerber, Florian

    2016-01-01

    Aims: We studied the precipitable water vapour (PWV) content near Cerro Armazones and discuss the potential use of our technique of modelling the telluric absorbtion lines for the investigation of other molecular layers. The site is designated for the European Extremely Large Telescope (E-ELT) and the nearby planned site for the Cherenkov Telescope Array (CTA). Methods: Spectroscopic data from the Bochum Echelle Spectroscopic Observer (BESO) instrument were investigated by using line-by-line radiative transfer model (LBLRTM) radiative transfer models for the Earths atmosphere with the telluric absorption correction tool molecfit. All observations from the archive in the period from December 2008 to the end of 2014 were investigated. The dataset completely covers the El Nino event registered in the period 2009-2010. Models of the 3D Global Data Assimilation System (GDAS) were used for further comparison. Moreover, for those days with coincidence of data from a similar study with VLT/X-shooter and microwave rad...

  2. Mathematical Modeling of the Dynamics of Salmonella Cerro Infection in a US Dairy Herd

    Science.gov (United States)

    Chapagain, Prem; van Kessel, Jo Ann; Karns, Jeffrey; Wolfgang, David; Schukken, Ynte; Grohn, Yrjo

    2006-03-01

    Salmonellosis has been one of the major causes of human foodborne illness in the US. The high prevalence of infections makes transmission dynamics of Salmonella in a farm environment of interest both from animal and human health perspectives. Mathematical modeling approaches are increasingly being applied to understand the dynamics of various infectious diseases in dairy herds. Here, we describe the transmission dynamics of Salmonella infection in a dairy herd with a set of non-linear differential equations. Although the infection dynamics of different serotypes of Salmonella in cattle are likely to be different, we find that a relatively simple SIR-type model can describe the observed dynamics of the Salmonella enterica serotype Cerro infection in the herd.

  3. Results of the latest transient well pressure tests at Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Abril G, A.; Vargas G, C.

    1981-01-01

    The equipment used in the interference and two-rate flow tests carried out at the Cerro Prieto geothermal field during 1980 are described. The results of two interference tests are presented, one between wells M-110 and M-104, and the other between wells M-7 and Q-757. The data was interpreted using type curve matching analysis. Results of two-rate flow tests carried out in wells M-102 and M-7 are also discussed. A technique for making two-rate flow tests is proposed. This approach, which attempts to avoid the uncertainty of present flow-rate measurements, makes use of devices for direct measurements of separated water and steam. Conclusions based on the above interpretations and recommendations for future tests are presented.

  4. MOVIMIENTOS DE LADERA Y PLANEAMIENTO URBANÍSTICO: EL CONFLICTO DEL CERRO DEL OPE, ARCHENA (MURCIA

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    María Dolores Gómez Moreno

    2009-01-01

    Full Text Available Los desprendimientos son un proceso natural que afecta, de forma generalizada en el Valle de Ricote, a las laderas del tipo cantil-talud. Su peligrosidad radica en que los bloques desprendidos del escarpe ruedan con facilidad, talud abajo, cuando son descalzados por efecto de la escorrentía superfi cial o desestabilizados por movimientos sísmicos. El planeamiento urbanístico se convierte en factor inductor del riesgo al clasifi car como urbanizables y urbanos suelos que, por su ubicación en pie de ladera, deberían excluirse de cualquier proceso urbanizador. Este es el caso de Archena en el entorno inmediato del cerro del Ope.

  5. Structure and age of the Cerro de Pasco Cu-Zn-Pb-Ag deposit, Peru

    Science.gov (United States)

    Cheney, E. S.

    1991-04-01

    The world-famous Cu-Zn-Pb-Ag deposit at Cerro de Pasco, Peru, consists of texturally massive pyrite, texturally massive sphalerite-galena-pyrite, and veins containing pyrite and enargite. Historically the deposit has been considered to be the hydrothermal product of the adjacent Miocene volcanic and intrusive complex (locally known as the “Vent”). However, both the texturally massive sulfides of the deposit and the pre-Miocene strata are cut by the Longitudinal fault, one of the largest faults in the district, but the Vent is not. Imbrication by the Longitudinal fault zone (duplex structures) has thickened the deposit so that it is amenable to open-pit mining. Dikes and pyrite-enargite veins pass from the Vent into the massive sulfides; fragments of massive pyrite occur in the Vent. Thus, no matter what their origin, the texturally massive sulfides are older and, therefore, genetically unrelated to the Vent.

  6. Burning down the brewery: establishing and evacuating an ancient imperial colony at Cerro Baul, Peru.

    Science.gov (United States)

    Moseley, Michael E; Nash, Donna J; Williams, Patrick Ryan; DeFrance, Susan D; Miranda, Ana; Ruales, Mario

    2005-11-29

    Before the Inca reigned, two empires held sway over the central Andes from anno Domini 600 to 1000: the Wari empire to the north ruled much of Peru, and Tiwanaku to the south reigned in Bolivia. Face-to-face contact came when both colonized the Moquegua Valley sierra in southern Peru. The state-sponsored Wari incursion, described here, entailed large-scale agrarian reclamation to sustain the occupation of two hills and the adjacent high mesa of Cerro Baúl. Monumental buildings were erected atop the mesa to serve an embassy-like delegation of nobles and attendant personnel that endured for centuries. Final evacuation of the Baúl enclave was accompanied by elaborate ceremonies with brewing, drinking, feasting, vessel smashing, and building burning.

  7. Volcanic hazard map for Telica, Cerro Negro and El Hoyo volcanoes, Nicaragua

    Science.gov (United States)

    Asahina, T.; Navarro, M.; Strauch, W.

    2007-05-01

    A volcano hazard study was conducted for Telica, Cerro Negro and El Hoyo volcanoes, Nicaragua, based on geological and volcanological field investigations, air photo analyses, and numerical eruption simulation. These volcanoes are among the most active volcanoes of the country. This study was realized 2004-2006 through technical cooperation of Japan International Cooperation Agency (JICA) with INETER, upon the request of the Government of Nicaragua. The resulting volcanic hazard map on 1:50,000 scale displays the hazards of lava flow, pyroclastic flows, lahars, tephra fall, volcanic bombs for an area of 1,300 square kilometers. The map and corresponding GIS coverage was handed out to Central, Departmental and Municipal authorities for their use and is included in a National GIS on Georisks developed and maintained by INETER.

  8. Mid amphibolite facies metamorphism of harzburgites in the Neoproterozoic Cerro Mantiqueiras Ophiolite, southernmost Brazil

    Directory of Open Access Journals (Sweden)

    HARTMANN LÉO A.

    2003-01-01

    Full Text Available Valuable information is retrieved from the integrated investigation of the field relationships, microstructure and mineral compositions of harzburgites from the Neoproterozoic Cerro Mantiqueiras Ophiolite. This important tectonic marker of the geological evolution of southernmost Brazilian Shield was thoroughly serpentinized during progressive metamorphism, because the oldest mineral assemblage is: olivine + orthopyroxene + tremolite + chlorite + chromite. This M1 was stabilized in mid amphibolite facies - 550-600ºC as calculated from mineral equilibria. No microstructural (e.g. ductile deformation of olivine or chromite or compositional (e.g. mantle spinel remnant of mantle history was identified. A metamorphic event M2 occurred in the low amphibolite facies along 100 m-wide shear zones, followed by intense serpentinization (M3 and narrow 1-3 m-wide shear zones (M4 containing asbestos.

  9. Burn Severities, Fire Intensities, and Impacts to Major Vegetation Types from the Cerro Grande Fire

    Energy Technology Data Exchange (ETDEWEB)

    Balice, Randy G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bennett, Kathryn D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wright, Marjorie A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2004-12-15

    The Cerro Grande Fire resulted in major impacts and changes to the ecosystems that were burned. To partially document these effects, we estimated the acreage of major vegetation types that were burned at selected burn severity levels and fire intensity levels. To accomplish this, we adopted independently developed burn severity and fire intensity maps, in combination with a land cover map developed for habitat management purposes, as a basis for the analysis. To provide a measure of confidence in the acreage estimates, the accuracies of these maps were also assessed. In addition, two other maps of comparable quality were assessed for accuracy: one that was developed for mapping fuel risk and a second map that resulted from a preliminary application of an evolutionary computation software system, called GENIE.

  10. La necrópolis medieval del Cerro de la Horca de Toledo

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    Ruiz Taboada, Arturo

    2009-06-01

    Full Text Available The archaeological excavation of part of a medieval necropolis at the Cerro de la Horca (Toledo has provided new information regarding burial traditions in Toledo. One formal aspect is common to the broad range of graves that have been brought to light, namely the pit that was dug for the burial, being of considerable depth in a number of cases. Because little is known of the funerary practices in Toledo during the Middle Ages and hardly any objects have been recovered in the excavation, it is difficult to identify the religious community to which it belonged. Whereas the location of Muslim and Christian cemeteries have been known through documentary and archaeological sources, only popular traditions quoted so far the Jewish necropolis, its location remaining thus a mystery.

    La excavación arqueológica desarrollada en un sector del Cerro de La Horca ha permitido conocer aspectos inéditos del ritual de enterramiento medieval en Toledo. Se ha documentado una amplia tipología de tumbas con un único elemento constructivo común para todas ellas, la excavación previa de una fosa que, en numerosos casos, alcanza gran profundidad. El desconocimiento sobre el mundo funerario medieval toledano y la falta de materiales arqueológicos representativos en esta necrópolis han obligado a reflexionar sobre la comunidad religiosa a la que pertenecen estos enterramientos. Por fuentes históricas y excavaciones previas, conocemos la localización de necrópolis musulmanas y cristianas. La localización de la(s judía(s había sido, al menos hasta ahora, una incógnita.

  11. CONTENEDORES Y CONTENIDOS. EXPLORANDO EL CONSUMO DE VEGETALES DURANTE EL PERÍODO TARDÍO (ANTOFAGASTA DE LA SIERRA, PROVINCIA DE CATAMARCA / Containers and contents. Exploring the vegetable consumption during the Late Period (Antofagasta de la Sierra, Pro

    Directory of Open Access Journals (Sweden)

    Leticia Inés Gasparotti

    2015-12-01

    Full Text Available En este trabajo se presentan los resultados obtenidos de la integración de diversas líneas de evidencia vinculadas al estudio de un recipiente cerámico recuperado en el sitio Corral Alto (Antofagasta de la Sierra, Prov. de Catamarca. Se analizan las características morfo-tecnológicas de este recipiente, en relación a su uso, para indagar en las prácticas cotidianas relacionadas con la obtención, consumo, procesamiento o almacenamiento de recursos vegetales. Al mismo tiempo, a través del análisis múltiple de microfósiles (fitolitos y almidones entre otras evidencias, se intenta una aproximación al uso y/o consumo de recursos vegetales silvestres y domesticados por parte de grupos agro-pastoriles durante el período Tardío (ca. 1000- 500 AP en la Puna Meridional. AbstractIn this paper we present the results of the integration of various lines of evidence related to the study of a ceramic container recovered at the site of Corral Alto (Antofagasta de la Sierra, Prov. Catamarca. We analyze morpho- technological characteristics of the vessel related to their use to enquire into the daily practices related to the collection, use, processing or storage of vegetal resources. At the same time, we conducted a multiple microfossil analysis (phytoliths and starches among other evidences to identify the use and /or consumption of wild and domesticated plant resources by agro-pastoralist groups during the Late Period (ca. 1000- 500 BP in the Southern Puna.

  12. Reflexiones acerca de la memoria y los usos del pasado a partir del análisis de un caso en el Noroeste argentino: Departamento de Santa María (provincia de Catamarca

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    Lorena B. Rodríguez

    2004-12-01

    Full Text Available La memoria social no es un mero reflejo de los hechos del pasado, sino una compleja construcción en la que tanto recuerdos individuales como colectivos, experiencias pasadas y situaciones presentes se intrincan inexorablemente. La memoria, entendida en esos términos, se constituye en un campo ideal para preguntar acerca de los diferentes sentidos que se le asignan al pasado desde o para el presente y analizar, por ende, las tensiones y disputas que tales asignaciones conllevan. En esta línea de trabajo, el objetivo del artículo es abordar el complejo proceso de atribuciones de sentido acerca del pasado que diferentes sectores y actores de la población del Dto. de Santa María (Pcia. de Catamarca realizan en la actualidad y, a la vez, reflexionar sobre algunas cuestiones teóricas que se desprenden del caso expuesto, en particular en torno a la idea del pasado como un recurso ilimitado pasible de ser usado por cualquier persona en cualquier momento.The social memory is not a mere reflection of the past events but a complex construction in which individual and colective memories, past experiences and current situations are inexorably mixed up. Memory, in that sense, became an ideal field to ask about the different meanings assigned to the past, from or for the present; thus allowing us to analize the tensions and disputes generated in this attributions. The aim of this paper is to approach the complex process by which different sectors and actors of Santa María district (Catamarca's province assign meanings to the past and, at the same time, to think about some theoretical subjects extracted of this case, particularly around the idea of the past as an unscared resource capable of being used by anyone at any moment.

  13. Mineralogical Characterization Of Topaz From Miarolitic Pegmatites And W-Bearing Greisen In The A-Type El Portezuelo Granite, Papachacra (Catamarca Province Caracterización mineralógica de topacio de pegmatitas miarolíticas y un greisen portador de W en el plutón de tipo A El Portezuelo (Granito Papachacra, provincia de Catamarca

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    Fernando Colombo

    2009-04-01

    Full Text Available The El Portezuelo Granite (Catamarca Province, NW Argentina, probably of Late Devonian or Early Carboniferous age, was emplaced at ≤ 2 kbar and displays the chemical characteristics of an A-type granite. It hosts small miarolitic pegmatites and dikes that belong to the NYF petrogenetic family, miarolitic class, miarolitic-REE subclass, with features more similar to those reported for the gadolinite-fergusonite type. Topaz is widespread both in pegmatites and in a W-bearing greisen genetically related to the granite. In pegmatites it occurs as crystals up to over 15 cm long, showing the forms {120} and {041} (dominant, and also {100}, {010}, {001}, {110}, {130}, {230}, {410}, {150}, {340}, {201}, {203}, {011}, {021}, {031}, {111}, {112}, {221}, {223}, and {445}. Crystals are colorless to pale yellow, more rarely brownish or bluish. Electron-microprobe analyses of gemmy crystals from pegmatites and greisen show that topaz is F-rich (between 19.01 and 20.12 wt. % F, most crystals being slightly zoned and has very low MgO and TiO2 (≤ 0.02 wt.%, low FeO (≤; 0.03 wt.%, and up to 0.10 wt.% CaO. Refractive indices and unit-cell dimensions reflect the F-rich nature of the studied topaz. This occurrence produces the finest crystals yet known from western South America but probably has no economic potencial as gemstock producer.El Granito El Portezuelo (Provincia de Catamarca, Argentina noroccidental, de probable edad devónica superior a carbonífera inferior, se emplazó a ≤ 2 kbar y posee las características de un granito de tipo A. Aloja pegmatitas miarolíticas y diques de reducidas dimensiones que pertenecen a la familia petrogenética NYF, clase miarolítica, subclase miarolítica-elementos de tierras raras, con rasgos más similares a los del tipo gadolinita-fergusonita. El topacio está bastante difundido en las pegmatitas y en un greisen portador de W genéticamente relacionado al granito. En pegmatitas se encuentra en cristales que

  14. Veta Esperanza Sudeste, un caso particular de enriquecimiento Supergénico en el yacimiento Alto de la blenda, distrito minero Agua de Dionisio, provincia de Catamarca Veta Esperanza Sudeste, a particular case of supergenic enrichment in the Alto de la Blenda deposit, Agua de Dionisio mining district, Catamarca Province.

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    Natalia Salado Paz

    2011-06-01

    Full Text Available Veta Esperanza Sudeste se localiza en el distrito minero Agua de Dionisio, Catamarca, dentro de la provincia geológica de las Sierras Pampeanas Occidentales. La geología del mismo corresponde a rocas metamórficas de bajo grado y cuerpos ígneos intrusivos graníticos a granodioríticos paleozoicos, sedimentos clásticos continentales terciarios y rocas pertenecientes al Complejo Volcánico Farallón Negro del Mioceno. Además, a areniscas, tobas del Plioceno y depósitos fluviales del Cuaternario. En el distrito mineralizado hay yacimientos diseminados y vetiformes, entre los últimos se mencionan los depósitos de oro y plata de Farallón Negro y Alto de La Blenda. Veta Esperanza Sudeste es un importante prospecto nuevo del sistema Alto de La Blenda, tiene una corrida de 200 m, potencia entre 0,30 y 6 m, rumbo NO e inclinación variable con la profundidad entre 75° a 56° al NE. La roca de caja es cuarzo monzonita, donde se observaron diferentes tipos de alteración hidrotermal: argílica, sericítica, silícica y propilítica. Presenta oxidación intensa, que afecta también a la veta. La paragénesis corresponde a: (1 minerales primarios (hipogénicos, pirita, galena, esfalerita, calcopirita, sulfosales de plata y oro, y (2 secundarios (supergénicos, pirolusita, psilomelano, hematina-goethita y sulfuros como calcosina y covelina. Los valores de leyes son de 0,5 a 40 g/tn de Au y 40 a 2.000 gr/tn de Ag con un recurso potencial de aproximadamente 400.000 tn de mineral.Veta Esperanza Sudeste is located in the Agua de Dionisio mining district, Catamarca, belonging to the Sierras Pampeanas Occidentales morphostructural province. The stratigraphic sequence is composed of Paleozoic low grade metamorphic rocks, granites and granodiorites, Tertiary continental clastic sedimentary rocks and the Farallón Negro Volcanic Complex of Miocene age, Pliocene sandstones and tuffites and Quaternary fluvial sediments. In the mining district are disseminated

  15. ESTUDIOS ETNOGRÁFICOS, PRÁCTICAS AGRÍCOLAS Y DIETA ÓPTIMA EN EL VALLE DE AMBATO, CATAMARCA, ARGENTINA, SIGLOS VI AL XI D. C. (Ethnographic Studies, Agricultural Practices, and Optimal Diet in the Ambato Valley, Catamarca, Argentina, VIth to XIth Centuries AD

    Directory of Open Access Journals (Sweden)

    Mariana Dantas

    2012-06-01

    Full Text Available En este trabajo se dan a conocer los estudios etnográficos llevados a cabo en el valle de Ambato, Catamarca, Argentina, los cuales estuvieron destinados a explorar diferentes aspectos de la práctica agrícola. Para ello, se indagó sobre el número de individuos involucrados en estas tareas, el rendimiento económico de los recursos vegetales cultivados y los costos y beneficios implicados en las distintas etapas de la cadena operativa. Los datos reunidos fueron sumados luego a los obtenidos a partir de trabajos similares realizados sobre recursos vegetales silvestres. Se pusieron a prueba a través de la utilización del modelo de programación lineal, tratando así de indagar sobre cuál podría haber sido la combinación óptima con la que cada uno de estos recursos habría contribuido a la dieta de los antiguos habitantes del valle. Los resultados alcanzados permitieron plantear que en estos espacios, durante los siglos VI al XI d. C., los productos derivados de la recolección, fundamentalmente el algarrobo (Prosopis sp., habrían constituido la mejor opción posible. Mientras que dentro de los productos derivados de la agricultura, el maíz (Zea mays habría sido la mejor elección. Estos datos coinciden con lo observado en el registro arqueológico del valle y con el caudal informativo que se cuenta para la región. ENGLISH: In this paper the authors report results of the ethnographic studies conducted in the Ambato Valley, Catamarca, Argentina, which were designed to explore different aspects of agricultural practice. To this end, data were collected in three areas: the number of individuals involved in these tasks, the economic performance of cultivated plant resources and the costs and benefits involved in the different stages of the operational chain. The data collected were then added to those obtained from similar works carried out on wild plant resources. They were tested using the linear programming model, thus trying to

  16. PRODUCCIÓN DE ALIMENTOS Y DIFERENCIACIÓN SOCIAL EN EL VALLE DE AMBATO, CATAMARCA, ARGENTINA (SIGLOS VI AL XI D. C.. UNA CONTRIBUCIÓN A LA PROBLEMÁTICA A TRAVÉS DEL ESTUDIO DE SILICOFITOLITOS (Food Production and Social Differentiation in the Ambato Valley, Catamarca, Argentina (6th-11th centuries AD: A Contribution to the Problem through the Study of Silicophytoliths

    Directory of Open Access Journals (Sweden)

    Germán G. Figueroa

    2015-01-01

    Full Text Available En este artículo se presenta la información obtenida de los estudios fitolíticos efectuados en el sedimento de dos estructuras agrícolas prehispánicas, situadas en la vertiente occidental del Valle de Ambato, Catamarca, Argentina. Los trabajos realizados se focalizaron en tratar de determinar las especies vegetales cultivadas y en evaluar la importancia que pudieron tener estos cultivos en un contexto social no igualitario como el registrado en la región estudiada. Los resultados logrados permiten plantear que en dichas estructuras se practicó el cultivo exclusivo de maíz (Zea mays asociado a la cría de animales domésticos (Lama glama. La producción intensiva y localizada de este tipo de cultivo, en un contexto como el de Aguada de Ambato, signado por una desigualdad social creciente, pudo haber constituido una de las estrategias a la hora de establecer y reproducir en el tiempo relaciones no igualitarias. ENGLISH: In this article we present information from studies of phytoliths from sediment collected from two pre-Hispanic farming structures located on the western side of the Ambato Valley, Catamarca, Argentina. The work focused on trying to determine what plant species were cultivated and assess the importance that these crops may have had in a non-egalitarian social context. The results suggest that maize (Zea mays crop, associated with the breeding of domestic animals (Lama glama, was performed exclusively in these structures. In a context such as Aguada, Ambato Valley, which was marked by increasing social inequality, intensive and localized production of this crop could have been one of the strategies for establishing and maintaining inegalitarian relations.

  17. Edad, caracterización petrográfica y Geoquímica del Granitoide del Cerro Falkner, Neuquén Age, petrography and geochemistry of Cerro Falkner's granitoid

    Directory of Open Access Journals (Sweden)

    Sabrina Crosta

    2008-03-01

    Full Text Available El Cerro Falkner se halla constituido por rocas graníticas infrayacentes a las volcanitas de la Formación Ventana de edad paleógena. Dichos intrusivos son de composición granodiorítica, metaluminosos a peraluminosos, subalcalinos, con características de granitos de arco volcánico concordantes con otros granitoides del segmento norte de la Cordillera Patagónica Septentrional. La edad obtenida por el método K-Ar sobre anfíboles de composición tschermakítica (125 ± 20 Ma indica una edad mínima perteneciente al Cretácico inferior para la granodiorita del cerro Falkner, por lo que sería incorrecto utilizar la denominación Formación Los Machis (Cretácico superior para estas rocas. Esta edad, permite vincular las rocas graníticas del área de estudio con el volcanismo representado por el Grupo Divisadero de edad predominantemente cretácica inferior.Cerro Falkner is composed of granitic rocks underlying volcanic rocks of the Ventana Formation of Paleogene age. Those intrusives are granodioritic in composition, metaluminous to peraluminous, subalkaline, with characteristics of volcanic arc granites that are concordant with other granitoids of the Cordillera Patagónica Septentrional's northern segment. The age obtained by the K-Ar method on tschemakitic amphiboles (125 ± 20 Ma points out a minimun age from the lower Cretaceous for the Cerro Falkner's granodiorite. Therefore the use of the term Los Machis Formation (Upper Cretaceous would be incorrect for these rocks. This age, allows us to relate the granitic rocks on the study area to the lower Cretaceous, coeval with the volcanism of the Divisadero Group.

  18. Corrosion in pipelines and well casings at the Cerro Prieto geothermal field, BC; Corrosion en tuberias de linea y de revestimiento de pozos del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Miranda Herrera, Carlos A.; Canchola Felix, Ismael; Raygoza Flores, Joaquin; Mora Perez, Othon [Comision Federal de Electricidad, Residencia General de Cerro Prieto, Mexicali, Baja California (Mexico)]. E-mail: carlos.miranda02@cfe.gob.mx

    2009-07-15

    In the area called Poligono Hidalgo, inside the Cerro Prieto IV zone in the Cerro Prieto geothermal field, BC, corrosion has occurred in the last few years on well casings and pipelines used for geothermal fluids. Corrosion test results are presented here for pipes, type API L-80 and ASTM A-53 grade B, which were subjected to condensate from wells 403 and 424. These wells have thrown corroded material from their respective casings. With these data we pinpoint corrosive conditions in this field area and determine which pipes are adequate to case wells in similar chemical, production conditions to minimize adverse effects and extend the life of the well, allowing more efficient exploitation of the deepest production zones in the reservoir. [Spanish] En el campo geotermico de Cerro Prieto, BC, dentro del area del Poligono Hidalgo en el sector conocido como Cerro Prieto IV, algunos pozos han presentado en los ultimos anos desgastes en sus tuberias de revestimiento y en las tuberias de linea para el transporte del fluido geotermico. Se presentan resultados de pruebas de corrosion con tuberias tipo API L-80 y ASTM A-53 grado B al ser sometidas al condensado de los pozos 403 y 424, los cuales han estado arrojando material de sus respectivas tuberias de revestimiento. Con estos datos se pretende conocer las condiciones corrosivas de esa zona del campo y determinar cual seria la tuberia ideal a utilizar en pozos con condiciones quimicas de produccion semejantes a fin de minimizar este efecto adverso y prolongar la vida de los pozos, a la vez que se permita la explotacion eficiente de las zonas productoras mas profundas del yacimiento.

  19. Study of the structural control of fluid flow within the Cerro Prieto Geothermal Field, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Noble, J.E.; Manon, M.A.; Lippmann, M.J.; Witherspoon, P.A.

    1977-10-01

    The Lawrence Berkeley Laboratory and the Comision Federal de Electricidad of Mexico are conducting a joint investigation of the Cerro Prieto Geothermal Field, located approximately 35 km south of Mexicali, Baja California, Mexico, in the Sea of Cortez-Salton Trough. Recent analyses of various geophysical/electrical logs, temperature logs, production and geochemical data and the subsequently developed preliminary model of the structure of the geothermal system and the distribution of geothermal fluids are presented. Techniques routinely applied to petroleum exploration were successfully used in the development of a preliminary model of this water-dominated system. The study indicates the upwelling of geothermal fluids along an east bounding fault from a deep, as yet unexplored source. The fluids dissipate into various sand horizons at various depths. The resulting stratigraphic and fluid flow model is of importance in planning additional developments of the Cerro Prieto Geothermal Field.

  20. Relationshipe Between Self-potential Anomalies and Hydraulic Flow In A Geothermal System: Application To Cerro-prieto, Baja California

    Science.gov (United States)

    Saracco, G.; Revil, A.; Pessel, M.

    The Cerro Prieto geothermal field is located in the alluvial plain of the Mexicali Valley, northern Baja California, Mexico, at about 35 km southeast of the city of Mexicali. The Cerro Prieto geothermal field is one of several high temperature water-dominated geothermal fields within the Salton Trough. We analyze here the self-potential distri- bution at the ground surface in order to determine the pattern of fluid flow in te sub- surface of this geothermal field. Various methods of analysis of self-potential anoma- lies are employed to reach this purpose. We use density probability tomography of monopolar and dipolar electrical sources and an Euler-type analysis. The hydraulic flow pattern found in this geothermal field is in agreement with that detemined from the heat flux inside the structure.

  1. CATÁLOGO COMENTADO DE LAS HEPÁTICAS DEL CERRO DE MAMAPACHA, MUNICIPIO DE CHINAVITA-BOYACÁ, COLOMBIA

    Directory of Open Access Journals (Sweden)

    WILSON RICARDO ÁLVARO ALBA

    2007-01-01

    Full Text Available Se presenta el catálogo comentado de 77 especies de hepáticas presentes en el cerro de Mamapacha en donde se organizan alfabéticamente las familias, géneros y es- pecies. Se proporciona información sobre la forma de crecimiento, abundancia, hábitat y distribución. Se resalta la presencia de 23 especies como nuevos registros para Boyacá.

  2. Oxygen isotope exchange in rocks and minerals from the Cerro Prieto geothermal system: Indicators of temperature distribution and fluid flow

    Energy Technology Data Exchange (ETDEWEB)

    Williams, A.E.; Elders, W.A.

    1981-01-01

    Oxygen isotopic compositions have been measured in drill cuttings and core samples from more than 40 wells ranging in depth to more than 3.5 km in the Cerro Prieto geothermal field. Profiles of isotopic ratios versus sampling depths provide information on the three-dimensional distribution of temperature and fluid flow. These parameters also indicate variations in the history of hydrothermal processes in different areas of the geothermal field.

  3. Cerro prieto y su correlación con los centros de dispersión del Golfo de California

    OpenAIRE

    Francisco Suárez Vidal; Ana Luz Quintanilla Montoya

    1996-01-01

    The Cerro Prieto geothermal tield is located in the Mexicali Valley, Baia California. Tectonically, this northern part of the Gulf of California has been classitied as a spreadmg center, within a transitional area of oceanic to continental conditions. Thermal, geologic-tectonic and magnetic evidente has been used to postulate the existence of a heat source in the area that is associated with magmatic processes, similar to those that occur in a typical oceanic spreading center. Based on the pe...

  4. Eventos de avalanchas y represamientos reiterados de ocurrencia prehistórica en la cuenca del río Villavil, sierra de Aconquija, Andalgalá, Catamarca

    Directory of Open Access Journals (Sweden)

    Aldo Luis Banchig

    2009-12-01

    Full Text Available Este trabajo presenta la existencia de un cuerpo sedimentario cuyos mecanismos depositacionales involucran procesos gravitacionales de gran envergadura, identificado como una avalancha de rocas (2,69 x10(9 m³, de carácter prehistórico con reactivaciones sucesivas, generado en la ladera oriental del cerro Zapallar (3.100 m s.n.m., en el extremo sur de la sierra del Aconquija (Sierras Pampeanas. Las múltiples reactivaciones de este depósito han generado reiterados represamientos en el río Villavil. La zona de estudio se emplaza en afloramientos de rocas ígneas graníticas del basamento y en proximidades de la intersección de dos grandes fallamientos regionales que, al parecer, han influido en la generación de estos eventos. Evidencias de actividad cuaternaria de los fallamientos regionales permiten deducir una posible sismogénesis asociada a estas estructuras, aunque esto no se correlaciona con la sismicidad histórica. La ocurrencia de colapsos sucesivos asociados a la oclusión reiterada del río Villavil, representa un riesgo potencial al desarrollo de la localidad de Villavil ubicada en la misma quebrada.

  5. Xenoliths of Cerro las Mercedes, Costa Rica: a Geochemical Record of Arc History?

    Science.gov (United States)

    Lindsay, F. N.; Gazel, E.; Herzberg, C. T.; Carr, M. J.; Feigenson, M. D.

    2006-12-01

    Over 70 ultramafic xenoliths, many with diameters of at least 3cm, open a window into the mantle beneath Cerro las Mercedes, Costa Rica. This quaternary vent is 70km behind the active volcanic front and near the northern boundary of the Caribbean Plateau. Both xenoliths and host lava remain well preserved in spite of substantial soil development in a rain forest environment. We analyzed the host lava and a subset of 30 rocks for bulk and mineral chemistry, which include both peridotite and pyroxenite populations. The host rock is Plio-Quaternary potassic alkaline basalt; depleted in SiO2 and Al2O3 and enriched in MgO and P2O5 relative to both present day and Miocene volcanics. In terms of trace elements, the host basalt has enriched LREEs and relative depletion of HFSEs, typical of island-arc basalt, both present and past. The coarse-grained pyroxenites have trace element chemistry akin to the volcanic front lavas of Costa Rica, although they are closer to chondritic values. Truly, they are more similar to basalts from Sarapiquí Miocene arc than to present day volcanic front basalts. Although there is enrichment in incompatible elements such as Ba and U and depletions in HFSEs, common in island arc basalts, the pyroxenites have a strong positive Pb anomaly that is characteristic only of the Miocene arc, not present day lavas. We interpret the pyroxenites as cumulates. The peridotite population includes dunites, spinel lherzolites and lherzolites. These rocks have Mg-numbers ranging from 87 to 92 and Cr-numbers ranging from 6 to 61. Whole rock geochemistry indicates that the peridotite xenoliths are fragments of mantle associated with the western Caribbean Plateau. SiO2, FeO, Al2O3 and MgO contents of several Cerro Mercedes peridotites are similar to those expected of hot residues that would form in a plume environment. Trace elements reveal some samples with enrichment of Ba and U, and depletion in Nb and Ta indicating variable extents of melt-rock reaction and

  6. ANALYSIS OF RECHARGE COOLDOWN AT THE WESTERN BOUNDARY OF CERRO PRIETO I GEOTHERMAL FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, P.; Lam, S.; Hunsbedt, A.; Esquer, C.; Marquez, R.; Hernandez, L. Cobo, J.

    1985-01-22

    Extensive study of the Cerro Prieto geothermal field has provided much geologic and thermodynamic data of its structurally-complex, liquid-dominated reservoir. Several of the studies investigated the resource characteristics of fluid and energy flow. An early report by Mercado (1975) showed that the heat source for the part of the reservoir under development, now called Cerro Prieto I (CPI), originated in the eastern part of the field. Subsequent studies confirmed the flow of hot water from the east. A summary of several experimental and numerical studies of fluid and energy transport in the field was given by Lippmann and Bodvarsson (1983). The hydrogeologic model of Halfman et al. (1982) shows hot-water flow from the east divided into a shallow (alpha) aquifer at about 120Om and a deeper (beta) aquifer at about 170Om depth. A cross section along an east-west direction shows a central upflow to the two aquifers and uncertain geology beyond the western border of the field near well M-9. It also shows a fault dividing the line of border wells at M-29 from the inner wells at M-25 to the east. The hydrogeology of the field was described by Sanchez and de la Pena (1981) as an alluvial unit from the surface to about 700 m over the production zone and a shale-sandstone unit comprising an upper, shallow (alpha) aquifer bounded below by a basement horst overlying a deeper (beta) aquifer. To date, much of the cumulative production at Cerro Prieto I has been from the alpha aquifer. Piezometric level measurements over the first 5 years of operation showed a decline in the western zone beyond the production wells. Over the 10-year period of continuous production, a significant temperature decline has been observed along the westernmost line of wells. Several investigations of the recharge characteristics of the field have been reported. Mercado (1975) and Elders et al. (1984) indicated a flow of cold groundwater from the east. Mercado also noted that cold water was entering

  7. Intense Seismic Activity at Chiles and Cerro Negro Volcanoes on the Colombia-Ecuador Border

    Science.gov (United States)

    Torres, R. A.; Cadena, O.; Gomez, D.; Ruiz, M. C.; Prejean, S. G.; Lyons, J. J.; White, R. A.

    2015-12-01

    The region of Chiles and Cerro Negro volcanoes, located on the Colombian-Ecuadorian border, has experienced an ongoing seismic swarm beginning in Aug. 2013. Based on concern for local residents and authorities, a cooperative broadband monitoring network was installed by the Servicio Geológico Colombiano in Colombia and the Instituto Geofísico of the Escuela Politécnica Nacional in Ecuador. Since November 2013 more than 538,000 earthquakes were recorded; although since May 2015 the seismicity has decreased significantly to an average of 70 events per day. Three large earthquake swarms with increasing energy occurred in Aug.-Oct. 2013, March-May 2014, and Sept.-Dec. 2014. By the end of 2014, roughly 400 earthquakes greater than M 3 had occurred with a maximum rate of 8000 earthquakes per day. The largest earthquake was a 5.6 ML on Oct. 20, 2014. This event produced an InSAR coseismic deformation of ~23 cm (S. Ebmeier, personal communication). Most events are typical brittle failure volcano-tectonic (VT) earthquakes that are located in a cluster beneath the southern flank of Chiles volcano, with depths between 1.5 and 10 km. Although the great majority of earthquakes are VT, some low-frequency (LF, ~0.5 Hz) and very-low-frequency (VLF) events have occurred. Particle motion analysis suggests that the VLF source migrated with time. While a VLF on Oct. 15, 2014 was located south of Chiles volcano, near the InSAR source, the VLF registered on Feb. 14, 2015 was likely located very close to Chiles Volcano. We infer that magma intrusion and resulting fluid exsolution at depths greater than 5 km are driving seismicity in the Chiles-Cerro Negro region. However earthquakes are failing in a manner consistent with regional tectonics. Relative relocations reveal a structure consistent with mapped regional faults. Thus seismicity is likely controlled by an interaction of magmatic and tectonic processes. Because the regional stress field is highly compressional and the volcanoes

  8. Subsurface Connections and Magma Mixing as revealed by Olivine- and Pyroxene-Hosted Melt Inclusions from Cerro Negro Volcano and the Las Pilas-El Hoyo Complex, Nicaragua.

    Science.gov (United States)

    Venugopal, S.; Moune, S.; Williams-Jones, G.

    2015-12-01

    Cerro Negro, the youngest volcano in the Central American Volcanic Belt, is a polygenetic cinder cone with relatively frequent explosive basaltic eruptions. Las Pilas, on the other hand, is a much larger and older complex with milder and less frequent eruptions. Based on historical data, these two closely spaced volcanoes have shown concurrent eruptive behavior, suggesting a subsurface connection. To further investigate this link, melt inclusions, which are blebs of melt trapped in growing crystals, were the obvious choice for optimal comparison of sources and determination of pre-eruptive volatile contents and magmatic conditions. Olivine-hosted inclusions were chosen for both volcanoes and pyroxene-hosted inclusions were also sampled from Las Pilas to represent the evolved melt. Major, volatile and trace elements reveal a distinct geochemical continuum with Cerro Negro defining the primitive end member and Las Pilas representing the evolved end member. Volatile contents are high for Cerro Negro (up to 1260 ppm CO2, 4.27 wt% H2O and 1700 ppm S) suggesting that volatile exsolution is likely the trigger for Cerro Negro's explosive eruptions. Las Pilas volatile contents are lower but consistent with degassing and evolutionary trends shown by major oxides. Trace element contents are rather unique and suggest Cerro Negro magmas fractionally crystallize while Las Pilas magmas are the products of mixing. Magmatic conditions were estimated with major and volatile contents: at least 2.4 kbar and 1170 °C for Cerro Negro melts and 1.3 kbar and 1130 °C for Las Pilas melts with an overall oxygen fugacity at the NNO buffer. In combination with available literature data, this study suggests an interconnected subsurface plumbing system and thus Cerro Negro should be considered as the newest vent within the Las Pilas-El Hoyo Complex.

  9. The Final Days of Paracas in Cerro del Gentil, Chincha Valley, Peru.

    Directory of Open Access Journals (Sweden)

    Henry Tantaleán

    Full Text Available This article describes and analyzes a highly significant archaeological context discovered in a late Paracas (400-200 BCE sunken patio in the monumental platform mound of Cerro Gentil, located in the Chincha Valley, Peru. This patio area was used for several centuries for ritual activities, including large-scale feasting and other public gatherings. At one point late in this historical sequence people deposited a great deal of objects in what is demonstrably a single historical event. This was quickly followed by a series of minor events stratigraphically immediately above this larger event. This entire ritual process included the consumption of liquids and food, and involved the offering of whole pottery, pottery fragments, botanical remains, bone, lithics, baskets, pyro-engraved gourds, mummies, and other objects. We interpret these events as an "abandonment ceremony" or "termination ritual" during the late Paracas period, one that may have lasted for weeks or even months. The subsequent Topará occupation at the site (ca. 200 BCE- AD 100 involved the architectural enhancement of the mound area, but the pattern of use of the patio itself ended. Such a termination ritual signals a reorganization in the regional political structure of Paracas society.

  10. Forecast of surface layer meteorological parameters at Cerro Paranal with a mesoscale atmospherical model

    CERN Document Server

    Lascaux, Franck; Fini, Luca

    2015-01-01

    This article aims at proving the feasibility of the forecast of all the most relevant classical atmospherical parameters for astronomical applications (wind speed and direction, temperature) above the ESO ground-base site of Cerro Paranal with a mesoscale atmospherical model called Meso-Nh. In a precedent paper we have preliminarily treated the model performances obtained in reconstructing some key atmospherical parameters in the surface layer 0-30~m studying the bias and the RMSE on a statistical sample of 20 nights. Results were very encouraging and it appeared therefore mandatory to confirm such a good result on a much richer statistical sample. In this paper, the study was extended to a total sample of 129 nights between 2007 and 2011 distributed in different parts of the solar year. This large sample made our analysis more robust and definitive in terms of the model performances and permitted us to confirm the excellent performances of the model. Besides, we present an independent analysis of the model p...

  11. Intersecting faults and sandstone stratigraphy at the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Vonder Haar, S.; Howard, J.H.

    1980-02-01

    The northwest-southeast trending Cerro Prieto fault is part of a major regional lineament that extends into Sonaro and has characteristics of both a wrench fault and an oceanic transform fault. The distribution of lithologies and temperature within the field was studied by comparing data from well cuttings, cores, well logs, and geochemical analyses. Across the earliest developed portion of the field, in particular along a 1.25-km northeast-southwest section from well M-9 to M-10, interesting correlations emerge that indicate a relationship among lithology, microfracturing, and temperature distribution. In the upper portion of Reservoir A of this stratigraphic section, between 1200 and 1400 m, the percentage of sandstones ranges from 20 to 55. Temperatures are 225/sup 0/ to 275/sup 0/C based on well logs, calcite isotope maxima, and Na-K-Ca indices. The study shows that an isothermal high in this vicinity corresponds to the lowest total percentage of sandstones. Scanning electron microphotographs of well cores and cuttings from sandstone and shale units reveal clogging, mineral dissolution, and mineral precipitation along microfractures. The working hypothesis is that these sandy shale and siltstone facies are most amenable to increased microfracturing and, in turn, such microfracturing allows for higher temperature fluid to rise to shallower depths in the reservoir.

  12. A simulation of the Cerro Hudson SO[sub 2] cloud

    Energy Technology Data Exchange (ETDEWEB)

    Schoeberl, M.R.; Lait, L.R.; Newman, P.A.; Krueger, A.J. (NASA Goddard Space Flight Center, Greenbelt, MD (United States)); Doiron, S.D. (Hughes STX Corp., Lanham, MD (United States))

    1993-02-20

    An isentropic trajectory model is used to simulate the evolution of the southern hemisphere SO[sub 2] cloud associated with the eruption of Cerro Hudson. By matching the parcel trajectories with total ozone mapping spectrometer SO[sub 2] retrievals, the principal stratospheric injection region is determined to be between 11 and 16 km in altitude. This region is characterized by weak wind shears and is located just poleward of the subtropical jet in the outer fringe of the stratospheric polar vortex. The lack of wind shear in the injection region explains the slow zonal dispersal of the SO[sub 2] cloud which was still clearly observed 19 days after the eruption. The trajectory model simulation of the SO[sub 2] cloud shows good agreement with observations for 7 days after the eruption. Using the potential vorticity and potential temperature estimates of the initial eruption cloud, the cloud position relative to the polar night jet is shown to be nearly fixed up to September 2, 1991, which was as long as the cloud was observed. This result suggests that the lower stratopsheric polar and mid-latitude regions are nearly isolated from each other during the late August period. 9 refs., 5 figs.

  13. Repetitive precision gravity studies at the Cerro Prieto and Heber geothermal fields

    Science.gov (United States)

    Grannell, R. B.

    1982-09-01

    To study subsidence and mass removal, a precise gravity network was established on 60 permanent monuments in the Cerro Prieto geothermal field in early 1978, and repeated annually through early 1981; the survey was tied to two bedrock sites outside the limits of the current production zone. The looping technique of station occupation was utilized, in which occupation of the base was followed by occupation of several stations, followed by a return to the base. Use of two LaCoste and Romberg gravity meters, and replication of values within loops as well as entire loops, enhanced precision such that the median standard deviations of the base-to-station differences, reduced to observed gravity values, ranged from 7 to 15 microgals for individual surveys. The smaller values were obtained as field and data reduction techniques were improved and experience was gained. A similar survey was initiated in the Heber area just north of the Mexican border in early 1980. It too was established on permanent monuments, was tied to bedrock stations outside the geothermal area, and used multiple repetitions of values with two meters to achieve high precision.

  14. Preliminary isotopic studies of fluids from the Cerro Prieto geothermal field

    Science.gov (United States)

    Truesdell, A.H.; Rye, R.O.; Pearson, F.J.; Olson, E.R.; Nehring, N.L.; Whelan, J.F.; Huebner, M.A.; Coplen, T.B.

    1979-01-01

    Preliminary isotopic studies of Cerro Prieto geothermal fluids and earlier studies of Mexicali Valley ground waters suggest local recharge of the geothermal system from the area immediately to the west. Oxygen isotope exchange of water with reservoir rock minerals at temperatures increasing with depth has produced fluids with oxygen-18 contents increasing with depth, and pressure drawdown in the southeastern part of the field has allowed lower oxygen-18 fluids to invade the production aquifer from above. The contents of tritium and carbon-14 in the fluid suggest only that the age of the fluid is between 50 and 10,000 years. The isotopic compositions of carbon and sulfur are consistent with a magmatic origin of these elements but a mixed sedimentary-organic origin appears more likely for carbon and is also possible for sulfur. Investigations of the isotopic compositions of geothermal and cold ground waters continue and are being expanded as fluids become available and as separation and analysis methods are improved. ?? 1979.

  15. Numerical Studies of the Heat and Mass Transport in the Cerro Prieto Geothermal Field, Mexico

    Science.gov (United States)

    Lippmann, M. J.; Bodavarsson, G. S.

    1983-06-01

    Numerical simulation techniques are employed in studies of the natural flow of heat and mass through the Cerro Prieto reservoir, Mexico and of the effects of exploitation on the field's behavior. The reservoir model is a two-dimensional vertical east to west-southwest cross section, which is based on a recent hydrogeologic model of this geothermal system. The numerical code MULKOM is used in the simulation studies. The steady state pressure and temperature distributions are computed and compared against observed preproduction pressures and temperatures; a reasonable match is obtained. A natural hot water recharge rate of about 1×10-2 kg/s per meter of field length (measured in a north-south direction) is obtained. The model is then used to simulate the behavior of the field during the 1973-1978 production period. The response of the model to fluid extraction agrees to what has been observed in the field or postulated by other authors. There is a decrease in temperatures and pressures in the produced region. No extensive two-phase zone develops in the reservoir because of the strong fluid recharge. Most of the fluid recharging the system comes from colder regions located above and west of the produced reservoir.

  16. Gas chemistry and thermometry of the Cerro Prieto, Mexico, geothermal field

    Science.gov (United States)

    Nehring, N.L.; D'Amore, F.

    1984-01-01

    Gas compositions of Cerro Prieto wells in 1977 reflected strong boiling in the reservoir around wells M-20 and M-25. This boiling zone appeared to be collapsing in 1982 when a number of wells in this area of the field were shut-in. In 1977 and 1982, gas compositions also showed boiling zones corresponding to faults H and L postulated by Halfman et al. (1982). Four gas geothermometers were applied, based on reservoir equilibria and calculated fugacities. The Fisher - Tropsch reaction predicted high temperatures and appeared to re-equilibrate slowly, whereas the H2S reaction predicted low temperatures and appeared to re-equilibrate rapidly. Hydrogen and NH3 reactions were intermediate. Like gas compositions, the geothermometers reflected reservoir processes, such as boiling. Surface gas compositions are related to well compositions, but contain large concentrations of N2 originating from air dissolved in groundwater. The groundwater appears to originate in the east and flow over the production field before mixing with reservoir gases near the surface. ?? 1984.

  17. Subsidence and Stress Change in the Cerro Prieto Geothermal Field, B. C., Mexico

    Science.gov (United States)

    Glowacka, E.; Sarychikhina, O.; Nava, F. A.

    2005-11-01

    Previous works have shown that ground deformation and seismicity in the Cerro Prieto geothermal field (CPGF) are due to both tectonics and field exploitation. Here, we use information about current tectonics and data from precision leveling surveys, to model tectonic and anthropogenic subsidence. Our results show that tectonic subsidence constitutes only ˜4% of the measured subsidence. Anthropogenic subsidence was evaluated using a model of rectangular tensional cracks, based on the hydrological model of the field, together with the Coulomb 2.0 program. From the resulting values of the fissure parameters and from extraction and injection data, we calculate that the volume changes caused by closure of the geothermal and cold water reservoirs account for only ˜3% and ˜7%, respectively, of the volume change which should occur due to extraction. Since 18% of the extracted fluids are reinjected, external recharge must compensate for about 72% of the expected volume reduction. An analysis of the changes in Coulomb stress caused by exploitation of the geothermal field suggest that even though the anthropogenic stresses account for only a fraction of tectonic stresses, they are large enough to trigger seismicity.

  18. New mammalian records in the Parque Nacional Cerros de Amotape, northwestern Peru

    Directory of Open Access Journals (Sweden)

    Cindy M. Hurtado

    2015-04-01

    Full Text Available The Pacific Tropical Rainforest and Equatorial Dry Forest are found only in southern Ecuador and northern Peru, and are among the most poorly known ecosystems of South America. Even though these forests are protected in Parque Nacional Cerros de Amotape (PNCA, they are threatened by fragmentation because of farming and agriculture. The aim of this study was to determine the medium and large mammalian species richness, using transect census, camera trapping, and specimen bone collection. Nine transects were established and 21 camera trap stations were placed along 16 km2 in three localities of PNCA, from August 2012 to April 2013. Total sampling effort was 215 km of transects and 4077 camera-days. We documented 22 species; including 17 with camera trapping, 11 with transect census, and 10 with specimen collection.  Camera traps were the most effective method, and four species (Dasyprocta punctata, Cuniculus paca, Leopardus wiedii and Puma concolor were documented only with this method. This comprised the first Peruvian record for Dasyprocta punctata, and the first record for the western slope of the Peruvian Andes for Cuniculus paca. Also, both specimen collections and sightings confirm the presence of Potos flavus, first record in the western slope of the Peruvian Andes. Panthera onca, Tremarctos ornatus and Saimiri sciureus are considered locally extinct, while several species are in need of further research. We highlight the importance of the high diversity of this rainforests and encourage local authorities to give the area the highest priority in conservation.

  19. Soil mercury levels in the area surrounding the Cerro Prieto geothermal complex, MEXICO.

    Science.gov (United States)

    Pastrana-Corral, M A; Wakida, F T; García-Flores, E; Rodriguez-Mendivil, D D; Quiñonez-Plaza, A; Piñon-Colin, T D J

    2016-08-01

    Even though geothermal energy is a renewable energy source that is seen as cost-effective and environmentally friendly, emissions from geothermal plants can impact air, soil, and water in the vicinity of geothermal power plants. The Cerro Prieto geothermal complex is located 30 km southeast of the city of Mexicali in the Mexican state of Baja California. Its installed electricity generation capacity is 720 MW, being the largest geothermal complex in Mexico. The objective of this study was to evaluate whether the emissions generated by the geothermal complex have increased the soil mercury concentration in the surrounding areas. Fifty-four surface soil samples were collected from the perimeter up to an approximate distance of 7660 m from the complex. Additionally, four soil depth profiles were performed in the vicinity of the complex. Mercury concentration in 69 % of the samples was higher than the mercury concentration found at the baseline sites. The mercury concentration ranged from 0.01 to 0.26 mg/kg. Our results show that the activities of the geothermal complex have led to an accumulation of mercury in the soil of the surrounding area. More studies are needed to determine the risk to human health and the ecosystems in the study area.

  20. Research Experiences for Undergraduates at Cerro Tololo Inter-American Observatory

    Science.gov (United States)

    Hoard, D. W.; Smith, R. C.

    2000-12-01

    Each year, Cerro Tololo Inter-American Observatory (CTIO), located in La Serena, Chile, hosts a Research Experiences for Undergraduates (REU) Program funded by the National Science Foundation. In general, REU programs bring a group of undergraduate students to the host institute for 10 weeks, where they are teamed-up with staff members to perform research projects. Unlike REU programs at other U.S. institutions, the CTIO program takes place outside the United States and during the southern summer/northern winter months of January--March. This offers students not only a chance to perform research and participate in the day-to-day life at a major astronomical observatory, but also provides a unique exposure to a foreign culture and an option for students who can take advantage of a non-traditional work experience during the academic year. CTIO REU students also benefit from interaction with their Chilean counterparts participating in the Prácticas de Investigación en Astronomía, an REU-like program operated by CTIO for Chilean undergraduates. Since 1995, CTIO has hosted 20 REU students (with 4 more coming in 2001). Twenty (and counting) publications have resulted from CTIO REU projects. In addition, since 1999, 100% of the CTIO REU students have presented the results of their research projects at meetings of the American Astronomical Society. We present here an overview of the REU program at CTIO.

  1. Prototype of a Space Fluorescence Detector at Cerro La Negra Mountain Site

    Science.gov (United States)

    Cordero, A.; Robledo, C.; Moreno, E.; Salazar, H.; Martinez, O.; Villaseñor, L.; Zepeda, A.; Khrenov, B.; Garipov, G.

    2003-07-01

    The prototype of space fluorescence detector TUS (see V. Alexandrov et al., this conference) is begin prepared for operation at the mountain site Cerro La Negra (atmosphere depth 600g /cm2). The fluorescence detector (FD) field of view cover the atmosphere above the EAS array at the Pico de Orizaba site (see O. Martinez et al., this conference), separated from the FD by ˜ 5k m. At night at energies E0 > 0.05EeV both FD and EAS array will operate as an "hybrid detector." The range of atmosphere depths available for observation of EAS tracks by FD in hybrid mode is 200g /cm2. FD will also observe EAS tracks at energies of about 1 EeV at distances R=25-50 km, at zenith angles > 450 (when the atmosphere depth is more than 850g /cm2 ) with direction of tracks perpendicular to the FD axis. The FD design and preliminary data of the FD performance will be presented.

  2. Model for the heat source of the Cerro Prieto magma-hydrothermal system, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Elders, W.A.; Bird, D.K.; Williams, A.E.; Schiffman, P.; Cox, B.

    1981-01-01

    Earlier studies at Cerro Prieto led to the development of a qualitative model for fluid flow in the geothermal system before it was drilled and perturbed by production. Current efforts are directed towards numerical modeling of heat and mass transfer in the system in this undisturbed state. This one-dimensional model assumes that the heat source was a single basalt/gabbro intrusion which provided heat to the system as it cooled. After compilation of various information of the physical properties of the reservoir, the enthalpy contained in two 1 cm thick sections across the reservoir orthogonal to each other was calculated. Various shapes, sizes and depths for the intrusion were considered as initial conditions and boundary conditions for the calculations of heat transfer. A family of numerical models which so far gives the best matches to the conditions observed in the field today have in common a funnel-shaped intrusion with a top 4 km wide emplaced at a depth of 5 km some 30,000 to 50,000 years ago, providing heat to the geothermal system.

  3. Hydrothermal flow regime and magmatic heat source of the Cerro Prieto geothermal system, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Elders, W.A.; Bird, D.K.; Schiffman, P.; Williams, A.E.

    1984-01-01

    This detailed three-dimensional model of the natural flow regime of the Cerro Prieto geothermal field, before steam production began, is based on patterns of hydrothermal mineral zones and light stable isotopic ratios observed in rock samples from more than 50 deep wells, together with temperature gradients, wireline logs and other data. At the level so far penetrated by drilling, this hydrothermal system was heated by a thermal plume of water close to boiling, inclined at 45/sup 0/, rising from the northeast and discharging to the west. To the east a zone of cold water recharge overlies the inclined thermal plume. Fission track annealing studies show the reservoir reached 170/sup 0/C only 10/sup 4/ years ago. Oxygen isotope exchange data indicate that a 12 km/sup 3/ volume of rock subsequently reacted with three times its volume of water hotter than 200/sup 0/C. Averaged over the duration of the heating event this would require a flow velocity through a typical cross-section of the reservoir of about 6 m/year. The heat in storage in that part of the reservoir hotter than 200/sup 0/C and shallower than 3 km depth is equivalent to that which would be released by the cooling of about 1 or 2 km/sup 3/ of basalt or gabbro magma.

  4. Model of the heat source of the Cerro Prieto magma-hydrothermal system, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Elders, W.A.; Bird, D.K.; Williams, A.E.; Schiffman, P.; Cox, B.

    1982-08-10

    Earlier studies at Cerro Prieto by UCR have led to the development of a qualitative model for field flow in the geothermal system before it was drilled and perturbed by production. Current efforts are directed towards numerical modelling of heat and mass transfer in the system in this undisturbed state. A two-dimensional model assumes that the heat sources were a single basalt/gabbro intrusion which provided heat to the system as it cooled. After compiling various information on the physical properties of the reservoir, the enthalpy contained in two 1cm thick section across the reservoir orthogonal to each other was calculated. Next various shapes, sizes and depths for the intrusion as initial conditions and boundary conditions for the calculation of heat transfer were considered. A family of numerical models which so far gives the best matches to the conditions observed in the field today have in common a funnel-shaped intrusion with a top 4km wide emplaced at a depth of 5km some 30,000 to 50,000 years ago, providing heat to the geothermal system. Numerical modelling is still in progress. Although none of the models so far computed may be a perfect match for the thermal history of the reservoir, they all indicate that the intrusive heat source is young, close and large.

  5. Application of oil-field well log interpretation techniques to the Cerro Prieto Geothermal Field

    Energy Technology Data Exchange (ETDEWEB)

    Ershaghi, I.; Phillips, L.B.; Dougherty, E.L.; Handy, L.L.

    1979-10-01

    An example is presented of the application of oil-field techniques to the Cerro Prieto Field, Mexico. The lithology in this field (sand-shale lithology) is relatively similar to oil-field systems. The study was undertaken as a part of the first series of case studies supported by the Geothermal Log Interpretation Program (GLIP) of the US Department of Energy. The suites of logs for individual wells were far from complete. This was partly because of adverse borehole conditions but mostly because of unavailability of high-temperature tools. The most complete set of logs was a combination of Dual Induction Laterolog, Compensated Formation Density Gamma Ray, Compensated Neutron Log, and Saraband. Temperature data about the wells were sketchy, and the logs had been run under pre-cooled mud condition. A system of interpretation consisting of a combination of graphic and numerical studies was used to study the logs. From graphical studies, evidence of hydrothermal alteration may be established from the trend analysis of SP (self potential) and ILD (deep induction log). Furthermore, the cross plot techniques using data from density and neutron logs may help in establishing compaction as well as rock density profile with depth. In the numerical method, R/sub wa/ values from three different resistivity logs were computed and brought into agreement. From this approach, values of formation temperature and mud filtrate resistivity effective at the time of logging were established.

  6. Unrest of Chiles - Cerro Negro volcanic complex: A binational Ecuador - Colombia effort

    Science.gov (United States)

    Ruiz, M. C.; Gomez, D.; Torres, R.; Cadena, O.; Mothes, P. A.; Anzieta, J. C.; Pacheco, D. A.; Bernard, B.; Acero, W.; Hidalgo, S.; Enriquez, W.; Cordova, A.

    2014-12-01

    The increasing seismic activity at the area of Chiles - Cerro Negro volcanic complex, located at the Ecuador-Colombian border, has been jointly monitored by the Instituto Geofisico - Ecuador and the Observatorio Vulcanologico y Sismologico de Pasto OVSP, a division of the Servicio Geologico Colombiano. Since April 2013, three seismic swarms have been detected in this area and more than 100.000 events are recorded since November 2013. The largest and more recent swarm has a daily average of 676 events between March and June 2014. Currently a seismic network of 8 seismic stations (5 in the Colombian and 3 in Ecuadorean side) are deployed in this area. Epicenters of more than 315 seismic events with magnitudes Ml>2.0 and 10 or more phases are located in an area 1-4 km south of Chiles volcano with shallow depths (up to 14 km). Most of events have magnitudes between 1.0 to 4.0. Nine events have magnitudes larger than 4.0 and the largest event occurred on April 30. 2014 with a local magnitude of 4.7 and inverse-transcurrent component focal mechanism. Waveforms and spectral patterns define these events as volcano-tectonic. Events with large magnitudes (above 3.0) show a very long-period component. Hot spring and deformation measurements also show signals of volcanic unrest.

  7. Measurements of air contaminants during the Cerro Grande fire at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Eberhart, Craig

    2010-08-01

    Ambient air sampling for radioactive air contaminants was continued throughout the Cerro Grande fire that burned part of Los Alamos National Laboratory. During the fire, samples were collected more frequently than normal because buildup of smoke particles on the filters was decreasing the air flow. Overall, actual sampling time was 96% of the total possible sampling time for the May 2000 samples. To evaluate potential human exposure to air contaminants, the samples were analyzed as soon as possible and for additional specific radionuclides. Analyses showed that the smoke from the fire included resuspended radon decay products that had been accumulating for many years on the vegetation and the forest floor that burned. Concentrations of plutonium, americium, and depleted uranium were also measurable, but at locations and concentrations comparable to non-fire periods. A continuous particulate matter sampler measured concentrations that exceeded the National Ambient Air Quality Standard for PM-10 (particles less than 10 micrometers in diameter). These high concentrations were caused by smoke from the fire when it was close to the sampler.

  8. 3-cerro y 4-mundo: los números del banquete en las ofrendas quechuas

    Directory of Open Access Journals (Sweden)

    David Lorente Fernández

    2010-12-01

    Full Text Available Las ofrendas quechuas del sur del Perú son platos alimenticios, banquetes destinados principalmente a la pachamama y los apus, pero también elaborados sistemas matemáticos regidos por operaciones sofisticadas. Sirviéndose de dos números fundamentales, el 3 y el 4, los especialistas rituales son capaces de transmitir mensajes polisémicos. Mediante el número 3 aglutinan clientes, parajes y cerros, en suma, «personas» capaces de interactuar entre sí. El 3 aparece en los k’intus de hojas de coca y en las oraciones que se recitan durante el proceso de realizar la ofrenda. Por el contrario, el número 4 no indica relaciones sino formas espaciales: es un operador geométrico que unifica la servilleta ceremonial (unk’uña, el papel envoltorio y el paquete acabado para representar las cuatro direcciones del mundo y hacer de la ofrenda un mundo en miniatura. Gracias a los dos números el ritualista puede recrear el cosmos, establecer convenios con los dioses y definir nuevas situaciones favorables para la vida de sus clientes.

  9. Characterization of the sodium layer at Cerro Pachon, and impact on laser guide star performance

    CERN Document Server

    Neichel, Benoit; Callingham, Joseph; Rigaut, Francois; Winge, Claudia; Trancho, Gelys; 10.1093/mnras/sts631

    2013-01-01

    Detailed knowledge of the mesopheric sodium layer characteristics is crucial to estimate and optimize the performance of Laser Guide Star (LGS) assisted Adaptive Optics (AO) systems. In this paper, we present an analysis of two sets of data on the mesospheric sodium layer. The first set comes from a laser experiment that was carried out at Cerro Tololo to monitor the abundance and altitude of the mesospheric sodium in 2001, during six runs covering a period of one year. This data is used to derive the mesospheric sodium column density, the sodium layer thickness and the temporal behavior of the sodium layer mean altitude. The second set of data was gathered during the first year of the Gemini MCAO System (GeMS) commissioning and operations. GeMS uses five LGS to measure and compensate for atmospheric distortions. Analysis of the LGS wavefront sensor data provides information about the sodium photon return and the spot elongation seen by the WFS. All these parameters show large variations on a yearly, nightly ...

  10. Influencia de las tradiciones ancestrales en la alimentación de la población rural del departamento de Santa María, provincia de Catamarca Influence of Ancestral Traditions in Rural People's Food in the District of Santa María, Province of Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    María del Pilar Rebellato

    2010-03-01

    Full Text Available El objetivo del presente trabajo fue describir la obtención, preparación y consumo de alimentos de la población rural del departamento Santa María, provincia de Catamarca. Se analizó la influencia y persistencia de las costumbres ancestrales por medio de un estudio descriptivo transversal simple, correlacional, exploratorio e inferencial. La muestra consistió en 222 mujeres de la zona rural de dicha región. La unidad de muestreo fue cada hogar, donde se entrevistó a una mujer. El medio de obtención de los alimentos predominante fue la compra y la agricultura. Se aprovecharon los recursos ambientales con formas de explotación como el pastoreo, la recolección de plantas y frutos autóctonos. Toda la familia adquiría y preparaba los alimentos, pero la madre se encargaba mayormente. El intercambio o trueque de alimentos básicos y su obtención por mitas fue muy escaso. Predominaron el hervido y guisado como métodos de cocción y el combustible más usado para cocinar fue el gas, pero métodos tradicionales como leña y carbón, puros o combinados con métodos modernos, fueron usados por una importante cantidad de familias. Las conservas fueron habituales, registrándose prácticas como el salado y la deshidratación por radiación solar. Las preparaciones tradicionales alternadas con las no tradicionales fueron las más consumidas, así como los postres tradicionales. Para beber entre comidas prefirieron las bebidas tradicionales. Las recetas se transmitieron por generaciones y los padres enseñaron a cocinar a las generaciones actuales. Se cambiaron las recetas originales en la preparación e ingredientes por problemas de salud. Los alimentos autóctonos fueron aceptados y los alóctonos subestimados y calificados negativamente. En conclusión, la mayoría de los pobladores rurales santamarianos conservaron las tradiciones en la obtención, preparación y tipo de alimentos consumidos y en la forma de transmitir la cultura alimentaria

  11. Evolution of the CP-I sector of the Cerro Prieto geothermal reservoir, BC, and exploitation alternatives; Evolucion del sector CP-I del yacimiento geotermico de Cerro Prieto, BC, y alternativas de explotacion

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez, Marco Helio [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, Baja California (Mexico)]. E-mail: marco.rodriguez01@cfe.gob.mx

    2010-01-15

    After 35 years of exploitation of the CP-I (Cerro Prieto I) sector of the Cerro Prieto geothermal field, its thermal conditions have been declined substantially; the number of production wells is reduced and exploitation has been abandoned in some zones. However with a binary cycle, it is still possible to generate electricity from the remaining reservoir energy. To do so, one needs to know a detailed reservoir history of the sector, identifying the best potential strata to be assessed. In this paper, the CP-I reservoir evolution is presented and its exploitation and main reservoir characteristics -which play important roles- are identified. The CP-I zones offering the best conditions for binary cycle exploitation are identified. Exploiting partially abandoned reservoir sections is crucial for the future of the field. If such sections can be made to produce, this will help reduce the progressive steam-production decline in the occurring since production began. The production decline had been mitigated by a large area available for drilling replacement production wells, but such an area is limited now, due to the vast number of operating wells. [Spanish] Despues de 35 anos de explotacion del yacimiento en el sector de CP-I (Cerro Prieto I) del campo geotermico de Cerro Prieto, BC, sus condiciones termicas han declinado considerablemente, por lo que el numero de pozos productores ha disminuido, dejando algunas zonas abandonadas a la explotacion. Sin embargo, aun es posible aprovechar la energia que contiene este sector del yacimiento para la generacion de electricidad mediante ciclo binario. Para ello primeramente se debe conocer en detalle cual ha sido la evolucion del yacimiento en este sector, identificando los estratos de mejor potencial para evaluarlos posteriormente. En este estudio se presenta la evolucion del yacimiento de CP-I como respuesta a su explotacion, identificando las principales caracteristicas del yacimiento que determinan su comportamiento. Asi

  12. Update of the basement model of the Cerro Prieto, B. C., geothermal field, Mexico; Actualizacion del modelo del basamento en el campo geotermico de Cerro Prieto, B.C., Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Lopez, Macario [Residencia General de Cerro Prieto, Comision Federal de Electricidad, Mexicali, Baja California (Mexico)

    1999-04-01

    With the aim to actualize the basement model of the Cerro Prieto Geothermal Field, a gravity interpretation has been held. We modeled in 2.5 D, nine profiles traced over the Bouguer anomaly map. Well data concerning lithology and density changes were used to fit the gravity models. Results of this work confirm that the geometry of the basement of Cerro Prieto, corresponds to a structural sequence. From west to east it starts as a big depression, continues with a strong uplift of the basement in the middle sector and finally deepens eastward in steps. The basement model proposed in the present work, defines a similar trend to that established by Fonseca y Razo (1980), but there are differences in basement depth in some areas. In the present model we interpret basement depths between 200 and 400 m deeper than in previous models to the south and northwest of the actual exploitation zone. [Spanish] Con el fin de actualizar el modelo del basamento en el Campo Geotermico de Cerro Prieto, se realizo una reinterpretacion gravimetrica, modelando en 2.5 D, 9 perfiles trazados sobre el mapa de anomalia de Bouguer. Utilizando la informacion litologica obtenida a traves de numerosas perforaciones profundas, se hicieron coincidir, dentro de los mofelos gravimetricos, las principales variaciones litologicas con cambios en la densidad. Los resultados de este trabajo reiteran que la geometria del basamento del Campo de Cerro Prieto, vista de W a E, corresponde con una secuencia estructural que se inicia con una gran depresion en el W, continua con un fuerte levantamiento y finalmente se extiende con una tendencia a profundizarse hacia el E de forma escalonada. El modelo de basamento derivado del presente trabajo, define una tendencia muy similar al modelo de basamento establecido (Fonseca y Razo, 1980), pero difiere en cuanto a la profundidad en algunos sectores del campo. En el actual trabajo se interpreta una profundidad entre 200 y 400 m mayor hacia el sur y noroeste de la

  13. Criteria to determine the depth of the production interval in wells of the Cerro Prieto geothermal field, Mexico; Criterios para determinar la profundidad del intervalo productor en pozos del campo geotermico de Cerro Prieto, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Leon Vivar, Jesus Saul de [Comision Federal de Electricidad, Residencia General de Cerro Prieto, Mexicali, B.C. (Mexico)]. E-mail: jesus.deleon@cfe.gob.mx

    2006-07-15

    Ways to select the depth of the production interval or to complete wells in the Cerro Prieto geothermal field have changed during the development of the field. From 1961 when drilling began to the middle of 2005, a total of 325 wells were drilled. The paper compares the approaches used in the past with those of the last ten years. The Cerro Prieto system has been classified as being of liquid-dominated and high-temperature. Today, after 33 years of commercial exploitation, it has experienced a series of thermal and geochemical fluid changes making it necessary to modify the ways to select the depth of the well production intervals, according to the observed behavior of the reservoir. The new criteria include the thermal approach, the geological approach, the geochemical approach and a comparative approach with neighboring wells. If most of these criteria are interpreted correctly, the success of a well is ensured. [Spanish] Los criterios para seleccionar la profundidad del intervalo productor o la terminacion de los pozos en el campo geotermico de Cerro Prieto han cambiado durante el desarrollo del mismo. De 1961, cuando se perforaron los primeros pozos, hasta mediados del 2005 se han perforado un total de 325 pozos. En el presente articulo se hara una breve revision de cuales han sido los criterios usados en el pasado y los que se han venido empleando en los ultimos diez anos. El yacimiento de Cerro Prieto ha sido clasificado como de liquido dominante, de alta temperatura, pero actualmente, despues de 33 anos de explotacion comercial, ha sufrido una serie de cambios termicos y geoquimicos en sus fluidos, por lo que ha sido necesario modificar los criterios para seleccionar la profundidad del intervalo productor de los pozos de acuerdo al comportamiento observado en el yacimiento. Los criterios actuales se dividen en cuatro: 1. Criterio termico, 2. Criterio geologico, 3. Criterio geoquimico y 4. Criterio comparativo de los pozos vecinos. Cuando la mayoria de estos

  14. Validating numerical simulations of snow avalanches using dendrochronology: the Cerro Ventana event in Northern Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    A. Casteller

    2008-05-01

    Full Text Available The damage caused by snow avalanches to property and human lives is underestimated in many regions around the world, especially where this natural hazard remains poorly documented. One such region is the Argentinean Andes, where numerous settlements are threatened almost every winter by large snow avalanches. On 1 September 2002, the largest tragedy in the history of Argentinean mountaineering took place at Cerro Ventana, Northern Patagonia: nine persons were killed and seven others injured by a snow avalanche. In this paper, we combine both numerical modeling and dendrochronological investigations to reconstruct this event. Using information released by local governmental authorities and compiled in the field, the avalanche event was numerically simulated using the avalanche dynamics programs AVAL-1D and RAMMS. Avalanche characteristics, such as extent and date were determined using dendrochronological techniques. Model simulation results were compared with documentary and tree-ring evidences for the 2002 event. Our results show a good agreement between the simulated projection of the avalanche and its reconstructed extent using tree-ring records. Differences between the observed and the simulated avalanche, principally related to the snow height deposition in the run-out zone, are mostly attributed to the low resolution of the digital elevation model used to represent the valley topography. The main contributions of this study are (1 to provide the first calibration of numerical avalanche models for the Patagonian Andes and (2 to highlight the potential of Nothofagus pumilio tree-ring records to reconstruct past snow-avalanche events in time and space. Future research should focus on testing this combined approach in other forested regions of the Andes.

  15. The CCAT-prime Extreme Field-of-View Submillimeter Telescope on Cerro Chajnantor

    Science.gov (United States)

    Koopman, Brian; Bertoldi, Frank; Chapman, Scott; Fich, Michel; Giovanelli, Riccardo; Haynes, Martha P.; Herter, Terry L.; Murray, Norman W.; Niemack, Michael D.; Riechers, Dominik; Schilke, Peter; Stacey, Gordon J.; Stutzki, Juergen; CCAT-prime Collaboration

    2017-01-01

    CCAT-prime is a six meter aperture off-axis submillimeter telescope that we plan to build at 5600m elevation on Cerro Chajnantor in Chile. The CCAT-prime optics are based on a cross-Dragone design with high throughput and a wide field-of-view optimized to increase the mapping speed of next generation cosmic microwave background (CMB) observations. These characteristics make CCAT-prime an excellent platform for a wide range of next generation millimeter and submillimeter science goals, and a potential platform for CMB stage-IV measurements. Here we present the telescope design for CCAT-prime and review the science goals.Taking advantage of the high elevation site, the first generation instrument for CCAT-prime will measure seven different frequency bands from 350um to 3mm. These seven bands will enable precise measurements of the Sunyaev-Zel’dovich effects (SZE) by separating contributions from CMB, thermal SZE, kinetic SZE, bright submm galaxies, and radio sources with a goal of extracting the peculiar velocities from a large number of galaxy clusters. Additional science priorities for CCAT-prime include: Galactic Ecology studies of the dynamic intersteller medium by mapping the fine structure lines [CI], [CII] and [NII] as well as high-excitation CO lines at the shortest wavelength bands; high redshift intensity mapping of [CII] emission from star-forming galaxies that likely dominates cosmic reionization at z~5-9 to probe the Epoch of Reionization; and next generation CMB polarization measurements to constrain inflation and cosmological models. The CCAT-prime facility will further our understanding of astrophysical processes from moments after the Big Bang to the present-day evolution of the Milky Way.

  16. Planning and Analysis of Fractured Rock Injection Tests in the Cerro Brillador Underground Laboratory, Northern Chile

    Science.gov (United States)

    Fairley, J. P., Jr.; Oyarzún L, R.; Villegas, G.

    2015-12-01

    Early theories of fluid migration in unsaturated fractured rock hypothesized that matrix suction would dominate flow up to the point of matrix saturation. However, experiments in underground laboratories such as the ESF (Yucca Mountain, NV) have demonstrated that liquid water can migrate significant distances through fractures in an unsaturated porous medium, suggesting limited interaction between fractures and unsaturated matrix blocks and potentially rapid transmission of recharge to the sat- urated zone. Determining the conditions under which this rapid recharge may take place is an important factor in understanding deep percolation processes in arid areas with thick unsaturated zones. As part of an on-going, Fondecyt-funded project (award 11150587) to study mountain block hydrological processes in arid regions, we are plan- ning a series of in-situ fracture flow injection tests in the Cerro Brillador/Mina Escuela, an underground laboratory and teaching facility belonging to the Universidad la Serena, Chile. Planning for the tests is based on an analytical model and curve-matching method, originally developed to evaluate data from injection tests at Yucca Mountain (Fairley, J.P., 2010, WRR 46:W08542), that uses a known rate of liquid injection to a fracture (for example, from a packed-off section of borehole) and the observed rate of seepage discharging from the fracture to estimate effective fracture aperture, matrix sorptivity, fracture/matrix flow partitioning, and the wetted fracture/matrix interac- tion area between the injection and recovery points. We briefly review the analytical approach and its application to test planning and analysis, and describe the proposed tests and their goals.

  17. Carbon-13 variations in fluids from the Cerro Prieto geothermal system

    Energy Technology Data Exchange (ETDEWEB)

    Janik, C.J.; Nehring, N.L.; Huebner, M.A.; Truesdell, A.H.

    1982-08-10

    The carbon isotope compositions of CO/sub 2/ in steam from Cerro Prieto production well have been measured for 1977, 1979, and 1982. Variations in the delta/sup 13/C values are caused by production-related changes in the chemical and physical parameters of the geothermal system. In 1977, most CO/sub 2/ in the reservoir was isotopically light (delta/sup 13/C = -6.4 +/- 0.4). Heavier CO/sub 2/ was produced from wells in the center of the field (M5,M26,M27) due to deposition of isotopically light calcite caused by near-well boiling. In 1979 nearly all well showed relatively heavy CO/sub 2/, probably due to expansion of aquifer boiling and calcite precipitation. In 1982, many wells in the central part of the field were shut in. The amount of drawndown decreased and as temperatures and pressures near the wells increased, the boiling zones collapsed. The CO/sub 2/ in the fluid then exchanged with the precipitated calcite and became isotopically lighter. The sensitivity of carbon isotopes to calcite precipitations caused by aquifer boiling and to reequilibration with this deposited calcite upon decrease of boiling suggests use as an indicator of these aquifer processes. Surficial CO/sub 2/ of thermal origin was collected in 1981. Generally, the carbon-13 contents were close to CO/sub 2/ from production wells except for high-temperature mud pots and fumaroles containing isotopically light CO/sub 2/ derived from near surface alteration of organic matter.

  18. Mexicali aquifer and its relation with the Colorado river and the Cerro Prieto geothermal reservoir

    Science.gov (United States)

    Ramirez-Hernandez, J.; Reyes-Lopez, J. A.; Carreon-Diazconti, C.; Lazaro-Mancilla, O.

    2008-05-01

    Until some years ago the Colorado River has been the main recharge source of the Mexicali and the Imperial Valley aquifers. River discharge interruption after the constructions of dams upstream (i.e. Parker, Davis and Hoover) and the creation of great irrigation systems in both Valleys have modified their dynamics. Currently, the distribution of water recharge is the network of irrigation and drainage channels that distribute water to more than 500.000 ha. The chemical quality of the recharge water also has changed because the irrigation run-off water has become more mineralized. On the other hand, the intense steam exploitation of the Cerro Prieto geothermal reservoir has inverted the flow direction from the Volcano Lagoon area that until the 60s constituted the discharge zone of the aquifer and the geothermal reservoir. In this work, changes in the aquifer water recharge regime, the phreatic level and the water chemical quality are analyzed. It was found that after the reduction of the annual water extraction from aquifer up to 750X106 m3, the static levels have reached a dynamic balance that could be altered if water seepage from the irrigation channels, specially from the All American Channel, is reduced. The total dissolved solids (TDS) concentration has increased from 1000 ppm in 1970 to 1800 ppm in 2005. The water of recent infiltration, the gradual cooling of the shallowest strata of the geothermal reservoir, and the almost total disappearance of the hydrothermal surface manifestations are evidences of groundwater flow inversion. The new source of groundwater recharge due to seepage of evaporation disposal geothermal brine pond is documented. This pond incorporates water with a very different chemical composition to the groundwater system. Therefore, mineralization of the shallow aquifer layers and the soil contamination process are identified. It was concluded that the aquifer hydrodynamics in the Valley of Mexicali depends on the irrigation system more

  19. Regional and local networks of horizontal control, Cerro Prieto geothermal area

    Science.gov (United States)

    Massey, B.L.

    1979-01-01

    The Cerro Prieto geothermal area in the Mexicali Valley 30 km southeast of Mexicali, Baja California, is probably deforming due to (1) the extraction of large volumes of steam and hot water, and (2) active tectonism. Two networks of precise horizontal control were established in Mexicali Valley by the U.S. Geological Survey in 1977 - 1978 to measure both types of movement as they occur. These networks consisted of (1) a regional trilateration net brought into the mountain ranges west of the geothermal area from survey stations on an existing U.S. Geological Survey crustal-strain network north of the international border, and (2) a local net tied to stations in the regional net and encompassing the area of present and planned geothermal production. Survey lines in this net were selected to span areas of probable ground-surface movements in and around the geothermal area. Electronic distance measuring (EDM) instruments, operating with a modulated laser beam, were used to measure the distances between stations in both networks. The regional net was run using a highly precise long-range EDM instrument, helicopters for transportation of men and equipment to inaccessible stations on mountain peaks, and a fixed wing airplane flying along the line of sight. Precision of measurements with this complex long-range system approached 0-2 ppm of line length. The local net was measured with a medium-range EDM instrument requiring minimal ancillary equipment. Precision of measurements with this less complex system approached 3 ppm for the shorter line lengths. The detection and analysis of ground-surface movements resulting from tectonic strains or induced by geothermal fluid withdrawal is dependent on subsequent resurveys of these networks. ?? 1979.

  20. Validating numerical simulations of snow avalanches using dendrochronology: the Cerro Ventana event in Northern Patagonia, Argentina

    Science.gov (United States)

    Casteller, A.; Christen, M.; Villalba, R.; Martínez, H.; Stöckli, V.; Leiva, J. C.; Bartelt, P.

    2008-05-01

    The damage caused by snow avalanches to property and human lives is underestimated in many regions around the world, especially where this natural hazard remains poorly documented. One such region is the Argentinean Andes, where numerous settlements are threatened almost every winter by large snow avalanches. On 1 September 2002, the largest tragedy in the history of Argentinean mountaineering took place at Cerro Ventana, Northern Patagonia: nine persons were killed and seven others injured by a snow avalanche. In this paper, we combine both numerical modeling and dendrochronological investigations to reconstruct this event. Using information released by local governmental authorities and compiled in the field, the avalanche event was numerically simulated using the avalanche dynamics programs AVAL-1D and RAMMS. Avalanche characteristics, such as extent and date were determined using dendrochronological techniques. Model simulation results were compared with documentary and tree-ring evidences for the 2002 event. Our results show a good agreement between the simulated projection of the avalanche and its reconstructed extent using tree-ring records. Differences between the observed and the simulated avalanche, principally related to the snow height deposition in the run-out zone, are mostly attributed to the low resolution of the digital elevation model used to represent the valley topography. The main contributions of this study are (1) to provide the first calibration of numerical avalanche models for the Patagonian Andes and (2) to highlight the potential of textit{Nothofagus pumilio} tree-ring records to reconstruct past snow-avalanche events in time and space. Future research should focus on testing this combined approach in other forested regions of the Andes.

  1. Temporal Evolution of a Seismic Swarm at Chiles - Cerro Negro volcanic complex

    Science.gov (United States)

    Ruiz, Mario

    2015-04-01

    The increasing seismic activity in the area of the Chiles - Cerro Negro volcanic complex, located on the Ecuador-Colombian border, has been jointly monitored by the Instituto Geofisico - Ecuador and the Observatorio Vulcanologico y Sismologico de Pasto (OVSP), a division of the Servicio Geologico Colombiano. Since April 2013, three seismic swarms have been detected in this area, and more than 400.000 events have been recorded since November 2013. The largest and most recent swarm has a daily average of 3894 events between March and the 12th of December 2014. Currently a seismic network of 13 short- and broad-band stations (5 Colombian, 8 Ecuadorian) was deployed in this area. High quality epicenters of seismic events with magnitudes Ml>2.0, RMSChiles volcano with shallow depths (up to 14 km). Most events have magnitudes between 1.0 to 4.0. Fifteen events have magnitudes larger than 4.0 including an event that occurred on October 20, 2014. This event had a local magnitude of 5.7 and an oblique (strike-slip with some thrusting) focal mechanism. Waveforms and spectral patterns define these events as volcano-tectonic. However, events with moderate to large magnitudes (above 3.0) contain pronounced very-long-period components. Position time series recorded by a dual-frequency GPS receiver at the SE flank of Chiles show a slight departure from the normal tectonic trend beginning with the appearance of the last seismic swarm on or around September 30, 2014. This trend is subsequently punctuated by a sharp deformation transient related to the coseismic displacement of the October 20 event. After more than a year of very anomalous seismic activity and concurrent minor deformation, no evidence of surficial volcanic activity has been documented.

  2. Shallow earthquake inhibits unrest near Chiles-Cerro Negro volcanoes, Ecuador-Colombian border

    Science.gov (United States)

    Ebmeier, Susanna K.; Elliott, John R.; Nocquet, Jean-Mathieu; Biggs, Juliet; Mothes, Patricia; Jarrín, Paúl; Yépez, Marco; Aguaiza, Santiago; Lundgren, Paul; Samsonov, Sergey V.

    2016-09-01

    Magma movement or reservoir pressurisation can drive swarms of low-magnitude volcano-tectonic earthquakes, as well as occasional larger earthquakes (>M5) on local tectonic faults. Earthquakes >M5 near volcanoes are challenging to interpret in terms of evolving volcanic hazard, but are often associated with eruptions, and in some cases enhance the ascent of magma. We present geodetic observations from the first episode of unrest known to have occurred near Chiles and Cerro Negro de Mayasquer volcanoes on the Ecuador-Colombian border. A swarm of volcano-tectonic seismicity in October 2014 culminated in a Mw 5.6 earthquake south of the volcanoes. Satellite radar data spanning this earthquake detect displacements that are consistent with dextral oblique slip on a reverse fault at depths of 1.4-3.4 km within a SSW-NNE trending fault zone that last ruptured in 1886. GPS station measurements capture ∼20 days of uplift before the earthquake, probably originating from a pressure source ∼10-15 km south of Volcán Chiles, at depths exceeding 13 km. After the Mw 5.6 earthquake, uplift ceased and the rate of seismicity began to decrease. Potential mechanisms for this decline in activity include a decrease in the rate of movement of magma into the shallow crust, possibly caused by the restriction of fluid pathways. Our observations demonstrate that an earthquake triggered during volcanic unrest can inhibit magmatic processes, and have implications for the hazard interpretation of the interactions between earthquakes and volcanoes.

  3. Structural control on geothermal circulation in the Cerro Tuzgle-Tocomar geothermal volcanic area (Puna plateau, Argentina)

    Science.gov (United States)

    Giordano, Guido; Pinton, Annamaria; Cianfarra, Paola; Baez, Walter; Chiodi, Agostina; Viramonte, José; Norini, Gianluca; Groppelli, Gianluca

    2013-01-01

    The reconstruction of the stratigraphical-structural framework and the hydrogeology of geothermal areas is fundamental for understanding the relationships between cap rocks, reservoir and circulation of geothermal fluids and for planning the exploitation of the field. The Cerro Tuzgle-Tocomar geothermal volcanic area (Puna plateau, Central Andes, NW Argentina) has a high geothermal potential. It is crossed by the active NW-SE trans-Andean tectonic lineament known as the Calama-Olacapato-Toro (COT) fault system, which favours a high secondary permeability testified by the presence of numerous springs. This study presents new stratigraphic and hydrogeological data on the geothermal field, together with the analysis from remote sensed image analysis of morphostructural evidences associated with the structural framework and active tectonics. Our data suggest that the main geothermal reservoir is located within or below the Pre-Palaeozoic-Ordovician basement units, characterised by unevenly distributed secondary permeability. The reservoir is recharged by infiltration in the ridges above 4500 m a.s.l., where basement rocks are in outcrop. Below 4500 m a.s.l., the reservoir is covered by the low permeable Miocene-Quaternary units that allow a poor circulation of shallow groundwater. Geothermal fluids upwell in areas with more intense fracturing, especially where main regional structures, particularly NW-SE COT-parallel lineaments, intersect with secondary structures, such as at the Tocomar field. Away from the main tectonic features, such as at the Cerro Tuzgle field, the less developed network of faults and fractures allows only a moderate upwelling of geothermal fluids and a mixing between hot and shallow cold waters. The integration of field-based and remote-sensing analyses at the Cerro Tuzgle-Tocomar area proved to be effective in approaching the prospection of remote geothermal fields, and in defining the conceptual model for geothermal circulation.

  4. Surface Deformation Associated with Geothermal Fluids Extraction at the Cerro Prieto Geothermal Field, Baja California, Mexico Revealed by DInSAR Technique

    Science.gov (United States)

    Sarychikhina, O.; Glowacka, E.; Mojarro, J.

    2016-08-01

    The Differential Synthetic Aperture Radar Interferometry (DInSAR) is widely used for surface deformation detection and monitoring.In this paper, ERS-1/2, ENVISAT and RADARSAT-2 synthetic aperture radar (SAR) images acquired between 1993 and 2014 were processed to investigate the evolution of surface deformation at the Cerro Prieto geothermal field, Baja California, Mexico. The conventional DInSAR together with the interferogram stacking method was applied. Average LOS (line of sight) displacement velocity maps were generated for different periods: 1993 - 1997, 1998 - 2000, 2004, 2005, 2007, 2009, and 2012 - 2014, revealing that the area corresponding to Cerro Prieto basin presented the important surface deformation (mainly subsidence) during the entire time of investigation. The changes in the surface deformation pattern and rate were identified. These changes have a good correlation in time with the changes of production in the Cerro Prieto geothermal field.

  5. Oxygen isotope exchange in rocks and minerals from the Cerro Prieto geothermal system: Indicators of temperature distribution and fluid flow

    Science.gov (United States)

    Williams, A. E.; Elders, W. A.

    1981-12-01

    Paleotemperatures different from the present thermal regime were studied by examining coexisting mineral systems which exchanged their oxygen with the geothermal brines at different rates. Oxygen isotopic compositions were measured in drill cuttings and core and core samples from more than 40 wells. Oxygen isotopic profiles of pore filling calcites in sandstones are a measure of the recent equilibrium temperature distribution. A three dimensional map was developed, showing the equilibrium temperatures in the geothermal field. A mass balance calculation was performed using measured 18O enrichment of the geothermal brine. This calculation implies an overall water; rock volume ratio of approximately 3:1 during the history of the Cerro Prieto system.

  6. Production induced boiling and cold water entry in the Cerro Prieto geothermal reservoir indicated by chemical and physical measurements

    Science.gov (United States)

    Grant, M.A.; Truesdell, A.H.; Manon, M.A.

    1984-01-01

    Chemical and physical data suggest that the relatively shallow, western part of the Cerro Prieto reservoir is bounded below by low permeability rocks, and above and at the sides by an interface with cooler water. There is no continuous permeability barrier around or immediately above the reservoir. Permeability within the reservoir is dominantly intergranular. Mixture with cooler water rather than boiling is the dominant cooling process in the natural state, and production causes displacement of hot water by cooler water, not by vapour. Local boiling occurs near most wells in response to pressure decreases, but no general vapour zone has formed. ?? 1984.

  7. Arterial oxygen saturation in healthy newborns delivered at term in Cerro de Pasco (4340 m) and Lima (150 m)

    OpenAIRE

    Gonzales Gustavo F; Salirrosas Amelia

    2005-01-01

    Abstract Background High altitude is associated with both low pulse oxygen saturation at birth and more pre-term deliveries. The present study was performed to determine pulse oxygen saturation in newborns at term in Cerro de Pasco (4340 m) and Lima (150 m) to test the hypothesis that low pulse oxygen saturation at birth at high altitudes was not observed at term deliveries. Methods The present study was designed to determine pulse oxygen saturation values through 1 minute to 24 hours and val...

  8. Production induced boiling and cold water entry in the Cerro Prieto geothermal reservoir indicated by chemical and physical measurements

    Energy Technology Data Exchange (ETDEWEB)

    Grant, M.A. (DSIR, Wellington, New Zealand); Truesdell, A.H.; Manon, A.

    1981-01-01

    Chemical and physical data suggest that the relatively shallow western part of the Cerro Prieto reservoir is bounded below by low permeability rocks, and above and at the sides by an interface with cooler water. There is no continuous permeability barrier around or immediately above the reservoir. Permeability within the reservoir is dominantly intergranular. Mixture with cooler water rather than boiling is the dominant cooling process in the natural state, and production causes displacement of hot water by cooler water, not by vapor. Local boiling occurs near most wells in response to pressure decreases, but no general vapor zone has formed.

  9. Fault Length Vs Fault Displacement Evaluation In The Case Of Cerro Prieto Pull-Apart Basin (Baja California, Mexico) Subsidence

    Science.gov (United States)

    Glowacka, E.; Sarychikhina, O.; Nava Pichardo, F. A.; Farfan, F.; Garcia Arthur, M. A.; Orozco, L.; Brassea, J.

    2013-05-01

    The Cerro Prieto pull-apart basin is located in the southern part of San Andreas Fault system, and is characterized by high seismicity, recent volcanism, tectonic deformation and hydrothermal activity (Lomnitz et al, 1970; Elders et al., 1984; Suárez-Vidal et al., 2008). Since the Cerro Prieto geothermal field production started, in 1973, significant subsidence increase was observed (Glowacka and Nava, 1996, Glowacka et al., 1999), and a relation between fluid extraction rate and subsidence rate has been suggested (op. cit.). Analysis of existing deformation data (Glowacka et al., 1999, 2005, Sarychikhina 2011) points to the fact that, although the extraction changes influence the subsidence rate, the tectonic faults control the spatial extent of the observed subsidence. Tectonic faults act as water barriers in the direction perpendicular to the fault, and/or separate regions with different compaction, and as effect the significant part of the subsidence is released as vertical displacement on the ground surface along fault rupture. These faults ruptures cause damages to roads and irrigation canals and water leakage. Since 1996, a network of geotechnical instruments has operated in the Mexicali Valley, for continuous recording of deformation phenomena. To date, the network (REDECVAM: Mexicali Valley Crustal Strain Measurement Array) includes two crackmeters and eight tiltmeters installed on, or very close to, the main faults; all instruments have sampling intervals in the 1 to 20 minutes range. Additionally, there are benchmarks for measuring vertical fault displacements for which readings are recorded every 3 months. Since the crackmeter measures vertical displacement on the fault at one place only, the question appears: can we use the crackmeter data to evaluate how long is the lenth of the fractured fault, and how quickly it grows, so we can know where we can expect fractures in the canals or roads? We used the Wells and Coppersmith (1994) relations between

  10. Geología de la región del Cerro Guanaquero, Río Diamante, Mendoza

    OpenAIRE

    Federico Fuentes; Ramos,Victor A.

    2008-01-01

    El estudio realizado presenta nuevos datos sobre un sector poco conocido de la Cordillera Principal de Mendoza, en la alta cuenca del río Diamante en las adyacencias del cerro Guanaquero, y los primeros datos geocronológicos de sus rocas volcánicas. Las unidades geológicas presentes en el área se dividen en cuatro grupos principales: secuencias sedimentarias mesozoicas marinas y continentales intensamente plegadas y falladas; intrusivos y volcanitas intermedias de edad neógena; rocas volcánic...

  11. Identificación macroscópica y microscópica de materias primas líticas en Cardonal (Valle del Cajón, Catamarca, Argentina. Una primera aproximación a su aprovechamiento

    Directory of Open Access Journals (Sweden)

    Natalia Sentinelli

    2013-12-01

    Full Text Available La identificación de los tipos de rocas empleados para la fabricación de artefactos líticos es un punto de partida inevitable a la hora comenzar a reconstruir y comprender las prácticas tecnológicas líticas de cualquier grupo de personas. Con este objetivo, en este trabajo se presentan los resultados de observaciones macroscópicas a ojo desnudo y estudios petrográficos microscópicos realizados sobre materiales líticos recuperados en una estructura habitacional (E1, , Núcleo 1 del sitio arqueológico Cardonal (Valle del Cajón, Pcia. de Catamarca. Los datos obtenidos en estos estudios permitieron la identificación de las materias primas líticas presentes. Sobre la base de un trabajo interpretativo de la información geológica de la zona, fue posible realizar algunas observaciones tentativas acerca de sus posibles procedencias. Finalmente, evaluando las distancias entre las fuentes potenciales de las variedades identificadas y Cardonal, y las frecuencias de éstas en la muestra artefactual recuperada en la Estructura 1 del sitio, se comienzan a reconstruir y discutir las posibles prácticas implicadas en su aprovisionamiento.

  12. Changes in steam production due to the reservoir conditions in Cerro Prieto, Baja California; Cambios en la produccion de vapor debido a las condiciones del yacimiento en Cerro Prieto, Baja California

    Energy Technology Data Exchange (ETDEWEB)

    Morales Cardenas, Ramon; Rodriguez Rodriguez, Marco H. [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, B.C. (Mexico)]. E-mail: marco.rodriguez01@gfe.gob.mx

    2011-07-15

    In more than 35 years of exploitation, thermodynamic conditions have changed in the Cerro Prieto geothermal reservoir. The effects are analyzed of the changes to the reservoir and their consequences to steam production in different field zones. For steam production, the most important features of reservoir fluids are enthalpies and pressures. The evolution of these features is presented in an enthalpy-pressure diagram. Here it can be seen that some reservoir zones have almost reached abandonment conditions. [Spanish] En mas de 35 anos de explotacion el yacimiento geotermico de Cerro Prieto ha experimentado cambios en sus condiciones termodinamicas. En este trabajo se analiza el efecto de esos cambios del yacimiento y su repercusion en la produccion de vapor para las diferentes zonas en las que se ha dividido el campo. Las propiedades mas importantes del fluido en el yacimiento para la produccion de vapor son su entalpia y su presion, por lo que se presenta la evolucion de esas propiedades en un diagrama de presion-entalpia, en el que se observa que hay zonas del yacimiento que estan proximas a alcanzar condiciones de abandono.

  13. Mexican-American Cooperative Program at the Cerro Prieto geothermal field: Analysis of the Nuevo Leon magnetic anomaly and its possible relation to the Cerro Prieto magmatic-hydrothermal system

    Science.gov (United States)

    Goldstein, N. E.; Wilt, M. J.; Corrigan, D. J.

    1982-10-01

    The broad dipolar magnetic anomaly whose positive peak is centered near Ejido Nuevo Leon, some 5 km east of the Cerro Prieto I Power Plant, has long been suspended to have a genetic relationship to the thermal source of the Cerro Prieto geothermal system. This suspicion was reinforced after several deep geothermal wells, drilled to depths of 3 to 3.5 km over the anomaly, intersected an apparent dike-sill complex consisting mainly of diabase but with minor rhyodacite. A detailed fit of the observed magnetic field to a computer model indicates that the source may be approximated by a tabular block 4 by 6 km in area, 3.7 km in depth, 2.3 km thick, and dipping slightly to the north. Mafic dike chips from one well, NL-1, were analyzed by means of electron microprobe analyses which showed them to contain a titanomagnetite that is paramagnetic at in-situ temperature conditions. As the dike mineralogy does not account for the magnetic anomaly, the magnetic source is believed to be a deeper, magnetite-rich assemblage of periodotite-gabbro plutons.

  14. Stress orientation and anisotropy based on shear-wave splitting observations in the Cerro Prieto fault area, Baja California, Mexico

    Science.gov (United States)

    Zúñiga, F. R.; Castro, R. R.; Domínguez, T.

    1995-03-01

    Digital seismograms continuously recorded from 1988 to 1992 by two stations of the RESNOM seismic network in northern Baja California, Mexico, were used to search for probable shear-wave anisotropic characteristics in the region of the Cerro Prieto fault. Shear-wave splitting was identified in many of the three-component records analyzed. We measured the polarization direction of the leading S wave inside the S-wave window as well as the delay times between fast and slow phases on those records displaying shear-wave splitting. For station CPX, which is nearest the Imperial Valley region to the north, the preferred polarization direction found in this study (azimuth 180°±10°) coincides with the direction of the regional maximum compressive stress determined for the region. This polarization direction can be interpreted in terms of the “Extensive Dilatancy Anisotropy” model as the effect of vertical parallel aligned cracks. The preferred polarization direction measured at LMX, however, gives an azimuth of 45°±5°. Thus, it appears that faults and fractures aligned oblique to the main tectonic trend have a greater influence on the anisotropic characteristics of the crust south of Cerro Prieto volcano than that of the regional stress field. Time delays between slow and fast S waves observed at CPX appear constant from 1988 to 1992 while delays measured at LMX for the same interval indicate a small increase with time which cannot be attributed to azimuthal variations of paths.

  15. ANALYSIS OF MUNICIPAL WASTEWATER AND ACID MINE DRAINAGE PASSIVE CO-TREATMENT AT CERRO RICO DE POTOSÍ, BOLIVIA

    Directory of Open Access Journals (Sweden)

    William H.J. Strosnider

    2015-06-01

    Full Text Available Acid mine drainage (AMD is a worldwide environmental problem. The passive co-treatment of AMD with municipal waste water (MWW is a cost effective approach that uses nutrients in MWW in order to treat high concentrations of metals and sulfate found in AMD. Cerro Rico de Potosí in Bolivia is one of the biggest mining cities in the world, and it is constantly facing problems with AMD. The goal of this study was to determine the reaction rates of Al, Fe, Mn, Zn, and other metals found in an AMD discharge from Cerro Rico by a three-stage reactor system. The AMD had a pH of 3.58 and acidity of 1080 mg/L as CaCO3 equivalent containing 12, 68, 17 and 550 mg/L of dissolved Al, Fe, Mn, and Zn respectively. The reaction rates of Al, Fe, Mn, and Zn were 1.43, 2.09, 0.01, and 0.10 d-1, respectively.

  16. Importaciones áticas del siglo V a.C. del Cerro del Prado (Algeciras, Cádiz

    Directory of Open Access Journals (Sweden)

    Cabrera, Paloma

    1996-12-01

    Full Text Available In this paper we analyze a group of Attic imports, found in the excavations of Cerro del Prado, a settlement situated in the Bahía de Algeciras (Cádiz. The great interest of this group lies in the fact that it belongs to a particular chronological period, the last third of the 5th century B.C., as we have not found later imports, and in the almost exclusive presence of black glazed vases, which gives US an idea of a very definitive demand of the punic society of the Iberian Peninsula regarding the trade of greek goods.

    Presentamos en este trabajo un conjunto de importaciones áticas halladas en las excavaciones del Cerro del Prado, situado en la bahía de Algeciras (Cádiz. El interés de este conjunto reside en su pertenencia a un momento cronológico muy concreto: el último tercio del siglo V a.C., no habiéndose hallado importaciones más modernas y en la presencia absoluta de vasos de barniz negro, lo que nos habla de una demanda muy determinada de la sociedad púnica peninsular frente al comercio de productos griegos.

  17. Gases in steam from Cerro Prieto geothermal wells with a discussion of steam/gas ratio measurements

    Science.gov (United States)

    Nehring, N.L.; Fausto, L.J.J.

    1979-01-01

    As part of a joint USGS-CFE geochemical study of Cerro Prieto, steam samples were collected for gas analyses in April, 1977. Analyses of the major gas components of the steam were made by wet chemistry (for H2O,CO2,H2S and NH3) and by gas chromatography (He,H2,Ar,O2,N2 and hydrocarbons). The hydrocarbon gases in Cerro Prieto steam closely resemble hydrocarbons in steam from Larderello, Italy and The Geysers, California which, although they are vapor-dominated rather than hot-water geothermal systems, also have sedimentary aquifer rocks. These sedimentary geothermal hydrocarbons are characterized by the presence of branched C4-6 compounds and a lack of unsaturated compounds other than benzene. Relatively large amounts of benzene may be characteristic of high-temperature geothermal systems. All hydrocarbons in these gases other than methane most probably originate from the thermal metamorphosis of organic matter contained in the sediments. ?? 1979.

  18. Paleomagnetism in the Determination of the Emplacement Temperature of Cerro Colorado Tuff Cone, El Pinacate Volcanic Field, Sonora, Mexico.

    Science.gov (United States)

    Rodriguez Trejo, A.; Alva-Valdivia, L. M.; Vidal Solano, J. R.; Garcia Amador, B.; Gonzalez-Rangel, J. A.

    2014-12-01

    Cerro Colorado Maar is located at the World Heritage Site, biosphere reserve El Pinacate and Gran Desierto del Altar, at the NNW region of Sonora, Mexico (in El Pinacate Volcanic Field). It is a tuff cone, about 1 km diameter, result of several phreatomagmatic episodes during the late Quaternary. We report paleomagnetic and rock magnetic properties from fusiform volcanic bombs obtained from the borders of Cerro Colorado. This study is based in the thermoremanent magnetization TRM normally acquired by volcanic rocks, which can be used to estimate the emplacement temperature range. We performed the experiments on 20 lithic fragments (10 cm to 20 cm approximately), taking 6-8 paleomagnetic cores from each. Rock magnetic experiments (magnetic susceptibility vs. temperature (k-T), hysteresis curves and FORC analysis, shows that the main magnetic mineral carriers of magnetization are titanomagnetite and titanohematite in different levels of intergrowth. The k-T curves suggest in many cases, only one magnetic phase, but also in other cases a second magnetic phase. Thermal demagnetization was used to demagnetize the specimens in detailed short steps and make a well-defined emplacement temperature determination ranges. We found that temperature emplacement determination range for these two magnetic phases is between 350-450 °C, and 550-580 °C, respectively. These results are consistent with those expected in an eruption of Surtsey type, showing a distinct volcanic activity compared to the other craters from El Pinacate volcanic field.

  19. A process for fire-related debris flow initiation, Cerro Grande fire, New Mexico

    Science.gov (United States)

    Cannon, S.H.; Bigio, E.R.; Mine, E.

    2001-01-01

    In this study we examine factors that pertain to the generation of debris flows from a basin recently burned by wildfire. Throughout the summer 2000 thunderstorm season, we monitored rain gauges, channel cross-sections, hillslope transects, and nine sediment-runoff traps deployed in a steep, 0??15 km2 basin burned by the May 2000 Cerro Grande fire in New Mexico. Debris flows were triggered in the monitored basin during a rainstorm on July 16, 2000, in response to a maximum 30 min rainfall intensity of 31 mm h-1 (return period of approximately 2 years). Eleven other storms occurred before and after the July storm; these storms resulted in significant runoff, but did not generate debris flows. The debris flows generated by the July 16 storm initiated on a broad, open hillslope as levee-lined rills. The levees were composed of gravel- and cobble-sized material supported by an abundant fine-grained matrix. Debris-flow deposits were observed only on the hillslopes and in the first and second-order drainages of the monitored basin. No significant amounts of channel incision were measured following the passage of the debris flows, indicating that most of the material in the flows originated from the hillslopes. Sediment-runoff concentrations of between 0??23 and 0??81 kg 1-1 (with a mean of 0-42 kg 1-1) were measured from the hillslope traps following the debris-flow-producing storm. These concentrations, however, were not unique to the July 16 storm. The materials entrained by the July 16 storm contained a higher proportion of silt- plus clay-sized materials in the debris flows. The difference in materials demonstrates the critical role of the availability of fine-grained wood ash mantling the hillslopes in the runoff-dominated generation of post-wildfire debris flows. The highest sediment-runoff concentrations, again not unique to debris-flow production, were produced from maximum 30 min rainfall intensities greater than 20 mm h-1. Copyright ?? 2001 John Wiley and Sons

  20. El megadeslizamiento del cerro Uritorco, ladera occidental de la Sierra chica de Córdoba

    Directory of Open Access Journals (Sweden)

    Claudio A Carignano

    2014-03-01

    Full Text Available En el extremo norte de la Sierra Chica de Córdoba, sobre el flanco oeste del cerro Uritorco (1.949 m s.n.m., se ha identificado un megadeslizamiento (30°49'55,46"S y 64°29'50,31"O. Los materiales movilizados del frente del escarpe de la falla Sierra Chica, han cubierto parcialmente el granito de Capilla del Monte y los abanicos aluviales pleistocenos del piedemonte. El lóbulo y bloques rotados del deslizamiento conforman un alto topográfico que oficia de límite entre los valles de Punilla (al sur y de Charbonier (al noroeste. Mediante técnicas de procesamiento e interpretación de imágenes satelitales multiespectrales de media (Landsat-ETM y muy alta resolución (GeoEye-1, análisis digital del terreno a partir de modelos de elevación (SRTM y Aster-GDEM y el correspondiente control de campo, se ha delimitado y caracterizado esta megageoforma nunca antes advertida. Dada la elevada sismicidad actual e histórica de la zona y los indicios morfotectónicos que señalan como activas a las fallas Sierra Chica y Pajarillo-Copacabana-Masa, se estima que este deslizamiento posiblemente fue gatillado por un evento sísmico, acontecido en alguna de esas estructuras. Tanto el depósito del deslizamiento como su cicatriz de despegue presentan un significativo grado de erosión hídrica. Por análisis comparativos con otros deslizamientos ya datados y de características similares, situados en el escarpe occidental de las Sierras de San Luis, se le asigna una edad pleistocena medio-tardía. Por su volumen y características (2,1 x109 m³ se estableció que se trata de un megadeslizamiento único en las Sierras de Córdoba y constituye uno de los deslizamientos de mayor tamaño entre los registrados hasta el presente en Argentina.

  1. El sistema de yacimientos de mamíferos miocenos del Cerro de los Batallones, Cuenca de Madrid: estado actual y perspectivas

    NARCIS (Netherlands)

    Morales, J.; Pozo, M.; Silva, P.G.; Domingo, M.S.; López-Antoñanzas, R.; Álvarez Sierra, A.; Antón, M.; Martín Escorza, C.; Quiralte, V.; Salesa, M.J.; Sánchez, I.M.; Azanza, B.; Calvo, J.P.; Carrasco, P.; García-Paredes, I.; Knoll, F.; Hernández Fernández, M.; Hoek Ostende, van den L.W.; Merino, L.; Meulen, van der A.J.; Montoya, P.; Peigné, S.; Peláez-Campomanes, P.; Sánchez-Marco, A.; Turner, A.; Abella, J.; Alcalde, G.M.; Andrés, M.; DeMiguel, D.; Cantalapiedra, J.L.; Fraile, S.; García Yelo, B.A.; Gómez Cano, A.R.; López Guerrero, P.; Oliver Pérez, A.; Siliceo, G.

    2008-01-01

    The Cerro de los Batallones (Los Batallones Butte) is located in the central-northern area of the Madrid Basin, central Spain. Nine vertebrates localities containing a large variety of mammals of Upper Vallesian Age (Late Miocene) have been found associated with the sediments forming the butte. From

  2. El frente de corrimiento andino al nivel de los cerros Penitentes y Visera (alta Cordillera de Mendoza: aspectos cronológicos y cartográficos

    Directory of Open Access Journals (Sweden)

    Jean-Claude Vicente

    2009-10-01

    Full Text Available El hallazgo de una iportante fauna de invertebrados marinos del Tithoniano superior a espaldas del cerro Penitentes en la secuencia carbonática basal de la primera escama del frente de corrimiento andino, confirma la lógica tectónica de un despegue de esta unidad a nivel del Yeso Principal y lleva a invalidar ciertas correlaciones litoestratigráficas y bosquejos paleogeográficos asignados a la Formación La Manga. Por otro lado, el análisis de algunos perfiles claves en torno al cerro Penitentes entre la quebrada Vargas y el cerro Visera permite presentar una reinterpretación tectónica del sector. Esta se sustenta en el reconocimiento y la diferenciación de las unidades terciarias básicas representadas por los Conglomerados Penitentes (Mioceno inferior y los Aglomerados Santa María (Mioceno superior en una relación muy similar a la descrita anteriormente al norte de Puente del Inca. El estudio permite seguir las interferencias, en un contexto polifásico, entre las reactivaciones del corrimiento Penitentes de piel fina y un cabalgamiento frontal de piel gruesa que repite la secuencia terciaria. La discordancia entre las secuencias terciarias y el emplazamiento de una klippe de Malm sobre los Conglomerados Penitentes del sinclinal del cerro Visera, conduce a otorgar cierta importancia a la fase del final del Mioceno inferior.

  3. An integrated model for the natural flow regime in the Cerro Prieto hydrothermal system based upon petrological and isotope geochemical criteria

    Energy Technology Data Exchange (ETDEWEB)

    Elders, W.A.; Williams, A.E.; Hoagland, J..

    1981-01-01

    Studies of cuttings and cores at Cerro Prieto have now been extended to more than 50 boreholes. The aims of this petrological and isotopic work are to determine the shape of the reservoir, its physical properties, and its temperature distribution and flow regime before the steam field was produced.

  4. Paleomagnetism of the Quaternary Cerro Prieto, Crater Elegante, and Salton Buttes volcanic domes in the northern part of the Gulf of California rhombochasm

    Energy Technology Data Exchange (ETDEWEB)

    de Boer, J.

    1980-02-01

    Deviating thermomagnetic directions in volcanics representing the second and fifth or sixth pulse of volcanism suggest that the Cerro Prieto volcano originated about 110,000 years B.P. and continued to be active intermittently until about 10,000 years ago.

  5. Land subsidence in the Cerro Prieto Geothermal Field, Baja California, Mexico, from 1994 to 2005: An integrated analysis of DInSAR, leveling and geological data

    Science.gov (United States)

    Sarychikhina, Olga; Glowacka, Ewa; Mellors, Robert; Vidal, Francisco Suárez

    2011-07-01

    Cerro Prieto is the oldest and largest Mexican geothermal field in operation and has been producing electricity since 1973. The large amount of geothermal fluids extracted to supply steam to the power plants has resulted in considerable deformation in and around the field. The deformation includes land subsidence and related ground fissuring and faulting. These phenomena have produced severe damages to the local infrastructure such as roads, irrigation canals and other facilities. In this paper, the technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) is applied using C-band ENVISAR ASAR data acquired between 2003 and 2006 to determine the extent and amount of land subsidence in the Mexicali Valley near Cerro Prieto Geothermal Field. The DInSAR results were compared with published data from precise leveling surveys (1994-1997 and 1997-2006) and detailed geological information in order to improve understanding of the temporal and spatial distributions of anthropogenic subsidence in the Mexicali Valley. The leveling and DInSAR data were modeled to characterize the observed deformation in terms of fluid extraction. The results confirm that the tectonic faults control the spatial extent of the observed subsidence. These faults likely act as groundwater flow barriers for aquifers and reservoirs. The shape of the subsiding area coincides with the Cerro Prieto pull-apart basin. In addition, the changes in spatial pattern and rate of the subsidence are correlated with the development of the Cerro Prieto Geothermal Field.

  6. Land subsidence in the Cerro Prieto Geothermal Field, 1 Baja California, Mexico, from 1994 to 2005. An integrated analysis of DInSAR, levelingand geological data.

    Energy Technology Data Exchange (ETDEWEB)

    Sarychikhina, O; Glowacka, E; Mellors, R; Vidal, F S

    2011-03-03

    Cerro Prieto is the oldest and largest Mexican geothermal field in operation and has been producing electricity since 1973. The large amount of geothermal fluids extracted to supply steam to the power plants has resulted in considerable deformation in and around the field. The deformation includes land subsidence and related ground fissuring and faulting. These phenomena have produced severe damages to infrastructure such as roads, irrigation canals and other facilities. In this paper, the technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) is applied using C-band ENVISAR ASAR data acquired between 2003 and 2006 to determine the extent and amount of land subsidence in the Mexicali Valley near Cerro Prieto Geothermal Field. The DInSAR results were compared with published data from precise leveling surveys (1994- 1997 and 1997-2006) and detailed geological information in order to improve the understanding of temporal and spatial distributions of anthropogenic subsidence in the Mexicali Valley. The leveling and DInSAR data were modeled to characterize the observed deformation in terms of fluid extraction. The results confirm that the tectonic faults control the spatial extent of the observed subsidence. These faults likely act as groundwater flow barriers for aquifers and reservoirs. The shape of the subsiding area coincides with the Cerro Prieto pull-apart basin. In addition, the spatial pattern of the subsidence as well as changes in rate are highly correlated with the development of the Cerro Prieto Geothermal Field.

  7. Procesos tafonómicos, subsistencia y uso del espacio: análisis de la arqueofauna de un sitio agropastoril de la Puna Meridional Argentina (Punta de la Peña 9, Antofagasta de la Sierra, Catamarca

    Directory of Open Access Journals (Sweden)

    Sara M. L. López Campeny

    2005-12-01

    Full Text Available Se presentan los resultados del análisis de un conjunto de restos óseos faunísticos recuperados en una estructura arquitectónica (E2 excavada en el sitio Punta de la Peña 9. Dicho sitio se localiza en los Sectores Intermedios (3600 m snm, en la microregión de Antofagasta de la Sierra (Catamarca, Puna Meridional Argentina. El análisis incluyó una evaluación de los efectos de los procesos de formación del registro, un abordaje del conjunto óseo desde una perspectiva económica y un análisis de la distribución espacial de los restos óseos en los niveles ocupacionales del recinto. El abordaje de estas tres dimensiones amplias del conjunto arqueofaunístico nos permitió aproximarnos al estudio de múltiples aspectos entre los que destacamos: la evaluación del efecto de los factores de formación del registro en la integridad del conjunto óseo; las modalidades de uso del espacio en la estructura analizada; ciertas características de las secuencias de ocupación de la misma; los sistemas de descarte o actividades de mantenimiento de los espacios de uso intensivo; el conjunto de actividades llevadas a cabo y los patrones vinculados con la explotación, selección de partes y consumo de fauna.The results of the analysis of an assemblage of faunal bone remains recovered from an architectural structure (E2 excavated in the site Punta de la Peña 9 are presented. The site is located in the Intermediate Sectors (3600 m. above-sea-level in the micro-region of Antofagasta de la Sierra (Catamarca, Southern Puna, Argentina. The analysis included an evaluation of the effects of the formation processes of the archaeological record, a study of the bones from an economic perspective, and an analysis of the spatial distribution of bones in the occupation levels of the enclosure. Examination of these three broad dimensions of this archaeofaunal assemblage enabled us to study multiple aspects of this site. Among such aspects the following are

  8. Hydraulic model of the steam-lines network of the Cerro Prieto, B.C., geothermal field; Modelo hidraulico de la red de vaporductos del campo geotermico de Cerro Prieto, B.C.

    Energy Technology Data Exchange (ETDEWEB)

    Salaices, E; Garcia, A; Martinez J I; Ovando, R; Cecenas, M; Hernandez A F [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: salaices@iie.org.mx; Canchola, I; Mora, O; Miranda, C; Herandez, M; Lopez, S; Murillo, I [Comision Federal de Electricidad, B.C (Mexico)

    2007-01-15

    The steam-line network of the Cerro Prieto geothermal field is composed of 184 wells, and 162 of the wells are integrated and connected by pipes. Thirteen power units, with an installed electrical capacity of 720 MW, are fed by that network. The network length is 120 km, including pipes of several diameters with branches and interconnections. The extension and complexity of the steam-line system make it difficult to analyze the transport and supply of steam to the power plants. For that it was necessary to have a tool capable of analyzing the system and the performance of the network as a whole, as well as the direction and flow volumes in each part of the system. In this paper, a hydraulic model of the Cerro Prieto steam-line network is presented. The model can determine the performance of the whole network by quantifying the pressure drops, flows and heat losses of the components. The model analyses the consequences of changes in operating conditions, steam production, maintenance activities and design (such as the integration of new wells). The model was developed using PIPEPHASE 9.0, a numeric simulator of multi-phase flow in steady state with heat transfer. It is used to model systems and pipe networks for steam- and condensate-transport. [Spanish] La red de vaporductos del campo geotermico de Cerro Prieto esta compuesta por un conjunto de 184 pozos, de los cuales 162 son pozos integrados, interconectados entre si a traves de una red de tuberias. Por medio de esta red se alimentan 13 unidades generadoras de electricidad con una capacidad total instalada de 720 MWe. La red tiene una longitud aproximada de 120 kilometros y esta compuesta por tuberias de diferentes diametros, ramales, interconexiones, etc. La complejidad y extension del sistema de vaporductos hace muy dificil el analisis del transporte y suministro de vapor a las plantas generadoras. Lo anterior creo la necesidad de contar con una herramienta que ayudara en el analisis del sistema con el fin de

  9. Cost model for geothermal wells applied to the Cerro Prieto geothermal field case, BC Abstract; Modelo de costeo de pozos geotermicos aplicado para el caso del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Vaca Serrano, Jaime M.E [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)]. E-mail: jaime.vaca@cfe.gob.mx

    2008-01-15

    A project for drilling geothermal wells to produce electrical energy can be defined as a sequence of plans to get steam or geothermal fluids to satisfy a previously known demand, and, under the best possible conditions, to obtain payment. This paper presents a cost model for nine wells drilled at the Cerro Prieto geothermal field in 2005 and 2006 to supply steam to the power plants operating in the field. The cost model is based on the well cost, the initial steam production, the annual decline of steam, the drilling schedule and the break-even point for each well. The model shows the cost of steam by the ton and the sale price needed to determine the discount rate and the investment return time. [Spanish] Un proyecto de perforacion de pozos geotermicos puede definirse como una secuencia o sucesion de planes para obtener vapor o fluidos geotermicos destinados a satisfacer una demanda previamente determinada, que se emplearan principalmente para generar energia electrica, bajo las mejores condiciones para obtener un pago. Este trabajo presenta un modelo de costeo para nueve pozos en el campo geotermico de Cerro Prieto, que fueron perforados entre 2005 y 2006 como parte del suministro de vapor para las plantas generadoras que operan en este campo. El modelo de costeo se basa en el costo por pozo, la produccion inicial de vapor, la declinacion anual de vapor, los intereses de las obras de perforacion y el punto de equilibrio para cada pozo. Los resultados permiten conocer el costo de la tonelada de vapor y el precio de venta para determinar la tasa de descuento y el tiempo de retorno de la inversion.

  10. Noise reduction in steam-vent points at the Cerro Prieto geothermal field, BC; Reduccion del ruido en puntos de desfogue en el campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Miranda Herrera, Carlos A [Comision Federal de Electricidad, Residencia General de Cerro Prieto, Mexicali, B.C (Mexico)]. E-mail: carlos.miranda02@cfe.gob.mx

    2008-01-15

    Steam silencers have been placed on the power units regulation system of the Cerro Prieto geothermal field, but not where the steam-pipes vent high-pressure steam (rupture disks). Moreover, the power-unit silencers are large and their abilities to reduce noise depend on an external, uncontrollable factor: pores sizes in the volcanic rocks they are made of. Thus a compact, economic and relatively easy to construct metallic silencer was designed to be used at several points of dry-steam venting to minimize the noise. The design was based on orifice-plate equations and a prototype was constructed and tested. It proved capable of reducing noise by 30 decibels for atmospheric discharges of primary steam at operating pressures. The size of the silencer can be adjusted to the particular needs of each vent case. [Spanish] En el campo geotermico de Cerro Prieto solo existen silenciadores de vapor en el sistema de regulacion de las plantas generadoras, pero no en los sitios de desfogue de vapor a alta presion en los vaporductos (discos de ruptura). Ademas, los silenciadores de las plantas son muy robustos y su capacidad de reduccion del ruido depende de un factor externo no controlable, como es el tamano del poro de la roca volcanica con el que estan construidos. Por lo tanto, se diseno un silenciador metalico compacto, economico y relativamente facil de fabricar, para utilizarse en diversos puntos de descarga de vapor seco a fin de minimizar el ruido. El diseno se realizo con base en las ecuaciones de la placa de orificio. Se construyo un prototipo cuyas pruebas demostraron que es capaz de reducir el ruido hasta en 30 decibeles, al descargar desde la presion de operacion de vapor primario hacia la presion atmosferica. Las dimensiones del silenciador pueden ajustarse a las necesidades particulares de cada caso de desfogue.

  11. Minería, conflicto y mediadores locales: Minera San Xavier en Cerro de San Pedro, México Mineira, conflito e mediadores locais: Minera San Xavier em Cerro de San Pedro Mining, conflict and local brokers: Minera San Xavier in Cerro de San Pedro

    Directory of Open Access Journals (Sweden)

    Hernán Horacio Schiaffini

    2011-12-01

    Full Text Available Este trabajo indaga en las instancias de mediación que intervienen en la articulación de procesos económicos de gran escala y su puesta en práctica local. Basándonos en el conflicto que se produjo en el Municipio de Cerro de San Pedro (San Luis Potosí, México entre la empresa Minera San Xavier y el Frente Amplio Opositor (FAO a la misma, aplicamos el método etnográfico con el objetivo de describir las estructuras locales de mediación política y analizar sus prácticas y racionalidad. Intentamos demostrar así la importancia de los factores políticos locales en las vinculaciones entre estado, empresa y población.Este trabalho indaga nas instâncias de mediação que intervêm em processos econômicos de grande escala e sua posta em prática local. Baseando-nos no conflito no Cerro de San Pedro (San Luis Potosí, México entre a empresa Minera San Xavier e a Frente Amplio Opositor (FAO aplicamos o método etnográfico pra descrever as estruturas de mediação política locais e analisar suas práticas e racionalidade. Tenta-se demonstrar assim a importância dos fatores políticos locais nas vinculações entre estado, empresa e população.This paper investigates in instances of mediation involved in large-scale economic processes and local implementation. Analyzing the conflict in Cerro de San Pedro (San Luis Potosí, México among San Xavier mining company and the Frente Amplio Opositor (FAO, it applies an ethnographic approach to describe the local structures of political mediation and its practices and rationality. The work shows the relevance of local factors in the relationships between State, company and people.

  12. Notes on the ecology of Phyllodactylus reissi (Phyllodactylidae: Sauria in Parque Nacional Cerros de Amotape (Tumbes, Peru

    Directory of Open Access Journals (Sweden)

    Juan Carlos Jordán Arizmendi

    2012-02-01

    Full Text Available Some basics aspects on the ecology of the nocturnal gecko Phyllodactylus reissi from Parque Nacional Cerros de Amotape (Tumbes, Peru are described. This species used rock boulders (57,4% and trees (31,9% as microhabitats primarily, exhibiting a nocturnal activity pattern, with a peak between 2100-2200 hours, remaining active until midnight. Body temperature (mean 24,4 ºC was correlated with both air and substrate temperature, with the last variable affecting in higher degree (47% the body temperature of this species. The slightly high body temperature of Phyllodactylus reissi, compared to other Phyllodactylus geckos, could be related to nocturnal microhabitat use and diurnal retreat site selection. More studies on lizard ecology from this endangered ecosystem are needed.

  13. Estudio de la líqueno flora encontrada en el Cerro de Quininí, Tibacuy, Cundinamarca

    Directory of Open Access Journals (Sweden)

    Hormaza Francisco

    2000-12-01

    Full Text Available

    Se realizó un muestreo de la liquen o flora del cerro de Quininí, Tibacuy, Cundinamarca para estudiar las características morfológicas externas de los géneros de líquenes encontrados en el. A su vez se hizo la revisión bibliográfica acerca de dichos géneros, datando así la riqueza de líquenes en la zona con 8 géneros en total y con respecto al papel de bioindicadores se mostró el grado de intervención para el lugar.

  14. Dry steam feed zones and silica scaling as major controls of total flow enthalpy at Cerro Prieto, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Beall, J.J. [Calpine Corp., Santa Rosa, CA (United States); Ledesma, A.P.; Dios Ocampo, J. de [Constructora y Perforadora Latina S.A., Baja California (Mexico)

    1997-12-31

    Enthalpy and chloride data for Cerro Prieto well fluids define a mixing line between original reservoir liquid (1,300-1,500 J/g, 9,000-11,000 ppm Cl) and superheated steam (2870 J/g, 0 ppm Cl). The mixing relationship establishes that dry steam feed zones contribute to the total fluid flow of many wells. Fluids produced from newly completed or worked over wells often show rapid movement in either direction along the enthalpy-chloride mixing line. The direction of movement along the enthalpy-chloride mixing line depends upon whether increased formation boiling (increasing the dry steam flow to the well) or silica scaling in the formation and on the surface of the well bore (which inhibits the flow of dry steam) is the dominant process.

  15. Results of the first order leveling surveys in the Mexicali Valley and at the Cerro Prieto field

    Energy Technology Data Exchange (ETDEWEB)

    de la Pena L, A.

    1981-01-01

    The results obtained from the third leveling survey carried out by the Direccion General de Geografia del Territorio Nacional (previously DETENAL) during November and December 1979 are presented. Calculations of the changes in field elevation and plots showing comparisons of the 1977, 1978, and 1979 surveys are also presented. Results from a second order leveling survey performed to ascertain the extent of ground motion resulting from the 8 June 1980 earthquake are presented. This magnitude ML = 6.7 earthquake with epicenter located 15 km southeast of the Guadalupe Victoria village, caused fissures on the surface, the formation of small sand volcanos, and the ejection of ground water in the vicinity of the Cerro Prieto field. This leveling survey was carried out between benchmark BN-10067 at the intersection of the Solfatara canal and the Sonora-Baja California railroad, and benchmark BN-10055 located at the Delta station.

  16. Curie point depth from spectral analysis of aeromagnetic data from Cerro Prieto geothermal area, Baja California, México

    Science.gov (United States)

    Espinosa-Cardeña, J. M.; Campos-Enriquez, J. O.

    2008-10-01

    Using aeromagnetic data acquired in the area from the Cerro Prieto geothermal field, we estimated the depth to the Curie point isotherm, interpreted as the base of the magnetic sources, following statistical spectral-based techniques. According to our results the Curie point isotherm is located at a depths ranging from 14 to 17 km. Our result is somewhat deeper than that obtained previously based only in 2-D and 3-D forward modeling of previous low-quality data. However, our results are supported by independent information comprising geothermal gradients, seismicity distribution in the crust, and gravity determined crustal thickness. Our results imply a high thermal gradient (ranging between 33 and 38 °C/km) and high heat flow (of about 100 mW/m 2) for the study area. The thermal regime for the area is inferred to be similar to that from the Salton trough.

  17. Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: a telescoped low pressure/temperature metamorphic facies series

    Energy Technology Data Exchange (ETDEWEB)

    Schiffman, P.; Elders, W.A.; Williams, A.E.; McDowell, S.D.; Bird, D.K.

    1983-01-01

    In the Cerro Prieto geothermal field, carbonate-cemented, quartzofeldspathic sediments of the Colorado River delta are being actively metasomatized into calc-silicate metamorphic rocks by reaction with alkali chloride brines between 200/sup 0/ and 370/sup 0/C, low fluid and lithostatic pressures, and low oxygen fugacities. Petrologic investigations of drill cores and cutting from over 50 wells in this field identified a prograde series of calc-silicate mineral zones which include as index minerals: wairakite, epidote, prehnite, and clinopyroxene. Associated divariant mineral assemblages are indicative of a very low pressure/temperature metamorphic facies series which encompasses the clay-carbonate, zeolite, greenschist, and amphibolite facies. This hydrothermal metamorphic facies series, which is becoming increasingly recognized in other active geothermal systems, is characterized by temperature-telescoped dehydration and decarbonation mineral equilibria. Its equivalent should now be sought in fossil hydrothermal systems.

  18. Burning down the brewery: Establishing and evacuating an ancient imperial colony at Cerro Baúl, Peru

    Science.gov (United States)

    Moseley, Michael E.; Nash, Donna J.; Williams, Patrick Ryan; deFrance, Susan D.; Miranda, Ana; Ruales, Mario

    2005-01-01

    Before the Inca reigned, two empires held sway over the central Andes from anno Domini 600 to 1000: the Wari empire to the north ruled much of Peru, and Tiwanaku to the south reigned in Bolivia. Face-to-face contact came when both colonized the Moquegua Valley sierra in southern Peru. The state-sponsored Wari incursion, described here, entailed large-scale agrarian reclamation to sustain the occupation of two hills and the adjacent high mesa of Cerro Baúl. Monumental buildings were erected atop the mesa to serve an embassy-like delegation of nobles and attendant personnel that endured for centuries. Final evacuation of the Baúl enclave was accompanied by elaborate ceremonies with brewing, drinking, feasting, vessel smashing, and building burning. PMID:16293691

  19. IMPACT OF ADDITIONALS CONTAMINANTS DUE TO ACID MINE DRAINAGE IN TRIBUTARIES OF THE PILCOMAYO RIVER FROM CERRO RICO, POTOSÍ, BOLIVIA

    Directory of Open Access Journals (Sweden)

    William H.J. Strosnider

    2014-09-01

    Full Text Available Intensive mining and processing of the polymetallic sulfide ore body of Cerro Rico de Potosí (Bolivia has occurred since 1545. To further investigate acid mine drainage (AMD discharges and their link to downstream contamination, data were gathered during two sampling events during the most extreme periods of the dry and wet seasons of one year. Concentrations of Ag, B, Ba, Mo, Sb, Se, Sn and V in AMD and receiving streams were greater than Bolivian discharge limits and receiving water body guidelines as well as international agricultural use standards. High concentrations of rare earth metals have been documented in this area. Results indicate that contamination from mining has a larger scope than previously thought and underscore the importance of remediation.

  20. The ash deposits of the 4200 BP Cerro Blanco eruption: the largest Holocene eruption of the Central Andes

    Science.gov (United States)

    Fernandez-Turiel, Jose-Luis; Saavedra, Julio; Perez-Torrado, Francisco-Jose; Rodriguez-Gonzalez, Alejandro; Carracedo, Juan-Carlos; Lobo, Agustin; Rejas, Marta; Gallardo, Juan-Fernando; Osterrieth, Margarita; Carrizo, Julieta; Esteban, Graciela; Martinez, Luis-Dante; Gil, Raul-Andres; Ratto, Norma; Baez, Walter

    2015-04-01

    We present new data about a major eruption -spreading approx. 110 km3 ashes over 440.000 km2- long thought to have occurred around 4200 years ago in the Cerro Blanco Volcanic Complex (CBVC) in the Central Andes of NW Argentina (Southern Puna, 26°45' S, 67°45' W). This eruption may be the biggest during the past five millennia in the Central Volcanic Zone of the Andes, and possibly one of the largest Holocene eruptions in the world. Discrimination and correlation of pyroclastic deposits of this eruption of Cerro Blanco was conducted comparing samples of proximal (domes, pyroclastic flow and fall deposits) with distal ash fall deposits (up to 400 km from de vent). They have been characterized using optical and electron microscopy (SEM), X-ray diffraction, particle-size distribution by laser diffraction and electron microprobe and HR-ICP-MS with laser ablation for major and trace element composition of glass, feldspars and biotite. New and published 14C ages were calibrated using Bayesian statistics. An one-at-a-time inversion method was used to reconstruct the eruption conditions using the Tephra2 code (Bonadonna et al. 2010, https://vhub.org/resources/tephra2). This method allowed setting the main features of the eruption that explains the field observations in terms of thickness and grain size distributions of the ash fall deposit. The main arguments that justify the correlation are four: 1) Compositional coincidence for glass, feldspars, and biotite in proximal and distal materials; 2) Stratigraphic and geomorphological relationships, including structure and thickness variation of the distal deposits; 3) Geochronological consistency, matching proximal and distal ages; and 4) Geographical distribution of correlated outcrops in relation to the eruption centre at the coordinates of Cerro Blanco. With a magnitude of 7.0 and a volcanic explosivity index or VEI 7, this eruption of ~4200 BP at Cerro Blanco is the largest in the last five millennia known in the Central

  1. Una fosa-vertedero de época vettona en el Cerro de la Mesa (Alcolea de Tajo, Toledo

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    Chapa Brunet, Teresa

    2013-06-01

    Full Text Available The existence of pits filled with earth, ashes, pottery fragments and fauna, usually known as ash pits, rubbish pits or dumps, has been recognized on many Second Iron Age settlements of the Spanish Northern Plateau, generally linked with Vaccean and Vettonian groups. However, its distribution should be extended to the west of the Southern Plateau and eastern Extremadura, as evidenced by the example of the Cerro de la Mesa village and indications coming from other western sites. We offer here a detailed study of part of a rubbish pit where certain domestic remains were withdrawn in connection with a new project of urbanisation of the Vettonian village held on the transition from the 3rd to the 2nd centuries BC.La existencia de fosas rellenas con tierra, cenizas, fragmentos cerámicos y fauna denominadas genéricamente como cenizales, basureros o vertederos, es un hecho bien conocido en la Meseta Norte durante la Segunda Edad del Hierro, vinculándose con los grupos Vacceos y Vettones. Sin embargo, su distribución debe ampliarse al occidente de la Meseta Sur y oriente extremeño, como se evidencia tanto en el Cerro de la Mesa como a través de indicios documentados en otros yacimientos más occidentales. Se presenta aquí un detallado estudio de un sector de la fosa que actuó como vertedero para la retirada de ciertos restos domésticos con ocasión de la reurbanización en profundidad del poblado vettón que tuvo lugar en la transición del siglo III al II a.C.

  2. Constraining the Paleogene of South America: Magnetostratigraphy and paleoclimate proxy records from Cerro Bayo (Provincia de Salta, Argentina)

    Science.gov (United States)

    Hyland, E.; Cotton, J. M.; Sheldon, N. D.

    2012-12-01

    Records of rapid climatic and ecological shifts in the past are crucial for understanding global systems and for predicting future impacts of climate change. Transient and broad scale hyperthermal events during the Paleogene, such as the Paleocene-Eocene Thermal Maximum (PETM) and Early Eocene Climatic Optimum (EECO), have been studied extensively through both marine records and a significant terrestrial record from North America. Despite this, little evidence exists from the climatic and ecological histories of other major landmasses, which limits the effectiveness of global climate response predictions. Here we present an integrated paleoenvironmental reconstruction of the early Paleogene from a site in central South America (Cerro Bayo, Argentina), including a new magnetostratigraphic age model, pedological and sedimentological interpretation, whole rock geochemical climate proxies, isotopic environmental proxies, and microfloral assemblages. Cerro Bayo is a 235-meter terrestrial section that exposes the Tunal, Mealla, and Maiz Gordo Formations, and based on magnetostratigraphic interpolation spans roughly 58—50 Mya, including both the PETM and EECO events. These formations are composed primarily of reddish sandstone and siltstone, much of which exhibits features characteristic of a moderate degree of pedogenesis (i.e., Inceptisols and Alfisols). High-resolution climate proxies derived from paleosol geochemical compositions highlight rapid increases in mean annual temperature (>5°C) and precipitation (>300 mm yr-1) during the PETM, as well as more gradual increasing temperature and precipitation trends leading up to the EECO. Carbon isotope stratigraphy through the section also indicates a sizable negative excursion (~4‰) during the PETM, and generally positive isotopic trends during the early Eocene. Phytolith biostratigraphy also details changes in local vegetation composition during climatic events that corresponds to similar patterns seen in terrestrial

  3. Microestructuras de deformación en rocas granulíticas, Cerro La Crespa, Tandilia, Provincia de Buenos Aires

    Directory of Open Access Journals (Sweden)

    Lucrecia Jorgensen

    2008-06-01

    Full Text Available El cerro La Crespa, localizado un kilómetro al sur de la megacizalla de Azul, integra las sierras de Azul, las cuales componen parte del Sistema de Tandilia. El presente trabajo trata sobre el estudio petrográfico-microestructural, donde se determina la composición modal y arreglos texturales a escala de grano y una primera caracterización geoquímica de rocas granulíticas aflorantes en el sector NO del cerro La Crespa. A partir de tales análisis, se intenta dilucidar los mecanismos de deformación actuantes y las condiciones metamórficas alcanzadas. Se reconocen rocas con texturas granoblásticas de composición básica e intermedia. Dichas rocas evidencian deformación frágil-dúctil heterogénea, con desarrollo de fábricas miloníticas, acaecida luego de que el evento metamórfico alcanzara su máximo desarrollo. Las texturas primitivas y la asociación de minerales anhidros presentes indicarían que dichas rocas podrían ser consideradas dentro de la serie de las granulitas. En las milonitas se aprecian significativos cambios mineralógicos, ya que al aumentar la deformación se incrementa la proporción de minerales hidratados y simultáneamente se reduce la cantidad de minerales anhidros. Estas modificaciones hacen suponer que la deformación actuó bajo condiciones metamórficas medias a altas, en facies de anfibolita superior-granulita inferior. Esta interpretación está apoyada por los mecanismos de deformación observados, a saber, recristalización dinámica de feldespatos, piroxenos, anfíboles, biotita y cuarzo; elongación de piroxenos y desarrollo de microboudinage.

  4. Volcanismo máfico terciario de la Puna jujeña, los Cerros Negros de Jama.

    Directory of Open Access Journals (Sweden)

    Caffe, Pablo, J.

    2011-12-01

    Full Text Available Tertiary mafic volcanism of the Jujuy Puna, the Cerros Negros de Jama. The Cerros Negros de Jama (23°29’ S – 66°56’ W monogenetic volcanoes belong to a group of eruptive centers that are representative of the most mafic magmatism in the northern Puna during the Cenozoic. They comprise scoria cones and associated lava flows erupted during coeval strombolian and effusive volcanic activity.Aphyric to microporphyritic skeletal textures and microphenocryst assemblages dominated by olivine and/or orthopyroxene suggest inexistent or short residence times in supracrustal magma chambers, as well as magma temperatures higher than 1000º C and near to water saturation conditions. The frequent occurrence of magmatic quartz xenocrysts with different degrees of reaction suggests assimilation of silicic magmas/igneous rocks under variable P-T conditions. A combination of large ascent rates and strong turbulence, together with an overheating of the magmas would have been crucial for this in-route contamination process.The Jama volcanic rocks are basaltic andesites and andesites to trachyandesites which belong to the high-K calcalkaline series. The observed geochemical signature is typical of continental arc magmas, showing negative anomalies of Nb, Ta and P, La/Ta > 30 and Ba/Nb > 25. Two main groups of rocks with different evolution patterns can be distinguished from major and trace element diagrams. Different concentrations of some elements at intermediate degrees of evolution point to variable degrees of incompatibility for them, which in turn may have been caused by magma evolution at different depths from the same or different primary magmas.

  5. Stress controlled magma-earthquake interaction during unrest at Chiles-Cerro Negro Volcanoes (Ecuador-Colombian border)

    Science.gov (United States)

    Ebmeier, S. K.; Elliott, J. R.; Nocquet, J. M.; Biggs, J.; Mothes, P. A.; Lundgren, P.; Samsonov, S. V.; Jarrin, P.; Yepez, M.; Aguaiza, S.

    2015-12-01

    The movement of fluids beneath a volcano can cause deformation, and therefore changes to the subsurface stress field that manifest in swarms of low magnitude (Chiles-Cerro Negro volcanoes on the Ecuador-Colombian border. These volcanoes were previously considered to be historically inactive, but between 2013 and early 2015 there were three episodes of unrest characterised by VT swarms of increasing energy and duration. GPS measurements at two stations near Volcán Chiles show inflation over a time period of approximately twenty days prior to the 20th October, consistent with the intrusion of magma at half space depths >13 km. This inflation took place during a swarm of VT seismicity with thousands of low magnitude events per day and culminated in a M 5.6 earthquake on the 20th October, when inflation abruptly ceased. We measure coseismic displacements from the M 5.6 earthquake with data from three independent InSAR platforms and find that they are consistent with shallow slip of 1.2 m on an oblique reverse fault. This fault plane would have experienced positive Coulomb stress changes from some of the range of potential sources consistent with the inflation. Magmatic intrusion could therefore have contributed to the loading on the fault directly through stress changes caused by pressurisation, and indirectly through the decrease in effective friction coefficient due to elevated pore fluid pressure. The cessation of inflation immediately after the moderate earthquake suggests a link between the two events. We expect slip on the fault plane identified from the InSAR data to have resulted in compression in the shallow crust south of Volcán Chiles, above the source that had previously been inflating. This would have inhibited further ascent of magma. The Chiles-Cerro Nego unrest provides rare observations of interaction between magmatic intrusion and a moderate earthquake during volcanic unrest.

  6. Analysis of the Nuevo Leon Magnetic Anomaly and its possible relation to the Cerro Prieto magmatic-hydrothermal system

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, N.E.; Corrigan, D.J.; Wilt, M.J.

    1984-01-01

    The broad dipolar magnetic anomaly whose positive peak is centered near Ejido Nuevo Leon, some 5 km east of the Cerro Prieto I power plant, has long been suspected to have a genetic relationship to the thermal source of the Cerro Prieto geothermal system. This suspicion was reinforced after several deep geothermal wells, drilled to depths of 3-3.5 km over the anomaly, intersected an apparent dike-sill complex consisting mainly of diabase but with minor rhyodacite. A detailed fit of the observed magnetic field to a computer model indicates that the source may be approximated by a tabular block 4 x 6 km in area, 3.7 km in depth, 2.3 km thick, and dipping slightly to the north. Mafic dike chips from one well, NL-1, were analysed by means of electron microprobe analyses which showed them to contain a titanomagnetite that is paramagnetic at in situ temperature conditions. As the dike mineralogy does not account for the magnetic anomaly, the magnetic source is believed to be a deeper, magnetite-rich assemblage of peridotite-gabbro plutons. The suite of igneous rocks was probably emplaced at a shallow depth in response to crustal extension and thinning brought on by en echelon strike-slip faulting. The bottom of the magnetic source body, at an estimated depth of 6 km, is presumed to be at or near that of the Curie isotherm (575/sup 0/C) for magnetite, the principal ferromagnetic mineral in peridotiticgabbroic rocks. The geological model derived from the magnetic study is generally supported by other geophysical data. In particular, earthquake data suggest dike injection is occurring at depths of 6-11 km in an area beneath the magnetic source. Thus, it is possible that heat for the geothermal field is being maintained by continuing crustal extension and magmatic activity.

  7. Analysis of the Nuevo Leon magnetic anomaly and its possible relation to the Cerro Prieto magmatic-hydrothermal system

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, N.E.; Wilt, M.J.; Corrigan, D.J.

    1982-10-01

    The broad dipolar magnetic anomaly whose positive peak is centered near Ejido Nuevo Leon, some 5 km east of the Cerro Prieto I Power Plant, has long been suspected to have a genetic relationship to the thermal source of the Cerro Prieto geothermal system. This suspicion was reinforced after several deep geothermal wells, drilled to depths of 3 to 3.5 km over the anomaly, intersected an apparent dike-sill complex consisting mainly of diabase but with minor rhyodacite. A detailed fit of the observed magnetic field to a computer model indicates that the source may be approximated by a tabular block 4 by 6 km in area, 3.7 km in depth, 2.3 km thick, and dipping slightly to the north. Mafic dike chips from one well, NL-1, were analyzed by means of electron microprobe analyses which showed tham to contain a titanomagnetite that is paramagnetic at in-situ temperature conditions. As the dike mineralogy does not account for the magnetic anomaly, the magnetic source is believed to be a deeper, magnetite-rich assemblage of peridotite-gabbro plutons. the suite of igneous rocks was probably passively emplaced at a shallow depth in response to crustal extension and thinning brought on by strike-slip faulting. The bottom of the magnetic source body, at an estimated depth of 6 km, is presumed to be at or near that of the Curie isotherm (575/sup 0/C) for magnetite, the principal ferromagnetic mineral in peridotitic-gabbroic rocks. The geological model derived from the magnetic study is generally supported by other geophysical data. In particular, earthquake data suggest dike injection is occurring at depths of 6 to 11 km in an area beneath the magnetic source. Thus, it is possible that heat for the geothermal field is being maintained by continuing crustal extension and magmatic activity.

  8. Minería, conflicto y mediadores locales: Minera San Xavier en Cerro de San Pedro, México Mineira, conflito e mediadores locais: Minera San Xavier em Cerro de San Pedro Mining, conflict and local brokers: Minera San Xavier in Cerro de San Pedro

    OpenAIRE

    Hernán Horacio Schiaffini

    2011-01-01

    Este trabajo indaga en las instancias de mediación que intervienen en la articulación de procesos económicos de gran escala y su puesta en práctica local. Basándonos en el conflicto que se produjo en el Municipio de Cerro de San Pedro (San Luis Potosí, México) entre la empresa Minera San Xavier y el Frente Amplio Opositor (FAO) a la misma, aplicamos el método etnográfico con el objetivo de describir las estructuras locales de mediación política y analizar sus prácticas y racionalidad. Intenta...

  9. Configuration of the mudstones, gray- and coffee-colored shale lithologic units, zones of silica and epidote, and their relation to the tectonics of the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Cobo R, J.M.

    1981-01-01

    Based on well cuttings, five lithological units have been recognized within the area of what is now the Cerro Prieto geothermal field. These five units are described. Differences in origin, mineralogy, grading, color, compaction, etc., are shown.

  10. Microestructuras de deformación en rocas granulíticas, Cerro La Crespa, Tandilia, Provincia de Buenos Aires Deformation microstructures in granulitic rocks, Cerro La Crespa, Tandilia, province of Buenos Aires

    Directory of Open Access Journals (Sweden)

    Lucrecia Jorgensen

    2008-06-01

    Full Text Available El cerro La Crespa, localizado un kilómetro al sur de la megacizalla de Azul, integra las sierras de Azul, las cuales componen parte del Sistema de Tandilia. El presente trabajo trata sobre el estudio petrográfico-microestructural, donde se determina la composición modal y arreglos texturales a escala de grano y una primera caracterización geoquímica de rocas granulíticas aflorantes en el sector NO del cerro La Crespa. A partir de tales análisis, se intenta dilucidar los mecanismos de deformación actuantes y las condiciones metamórficas alcanzadas. Se reconocen rocas con texturas granoblásticas de composición básica e intermedia. Dichas rocas evidencian deformación frágil-dúctil heterogénea, con desarrollo de fábricas miloníticas, acaecida luego de que el evento metamórfico alcanzara su máximo desarrollo. Las texturas primitivas y la asociación de minerales anhidros presentes indicarían que dichas rocas podrían ser consideradas dentro de la serie de las granulitas. En las milonitas se aprecian significativos cambios mineralógicos, ya que al aumentar la deformación se incrementa la proporción de minerales hidratados y simultáneamente se reduce la cantidad de minerales anhidros. Estas modificaciones hacen suponer que la deformación actuó bajo condiciones metamórficas medias a altas, en facies de anfibolita superior-granulita inferior. Esta interpretación está apoyada por los mecanismos de deformación observados, a saber, recristalización dinámica de feldespatos, piroxenos, anfíboles, biotita y cuarzo; elongación de piroxenos y desarrollo de microboudinage.This work deals with a petrographic- microstructural study in order to determine the modal composition and textural arrangement on a grain scale and the first geochemistry characterization of granulitic rocks on the NW of the cerro La Crespa, which is located about 1 km south of the Azul Megashear and forms part of the sierras de Azul in the Tandilia System

  11. Composición, estructura y diversidad del cerro El Águila, Michoacán, México Composition, structure and diversity of the cerro El Águila, Michoacán, Mexico

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    Luis Eduardo Zacarias-Eslava

    2011-09-01

    Full Text Available Se describe la composición, estructura y diversidad de la vegetación presente en el cerro El Águila, Michoacán. Se reconocieron fisonómicamente 5 tipos de vegetación y en cada uno se establecieron 16 parcelas circulares de 400 m² (3.2 ha para censar los individuos leñosos ≥ 10 cm d.a.p., con una parcela anidada de 100 m² (0.8 ha para los individuos entre 2.5 y 9.9 cm d.a.p. El muestreo incluyó 46 especies agrupadas en 33 géneros y 21 familias. Los bosques tropical caducifolio y de Quercus deserticola tuvieron los valores más bajos de altura promedio ( 11 m y área basal (> 40 m²/ha. La diversidad fue mayor en el bosque tropical caducifolio (S=23 y α =5.4 y menor en el de Quercus-Pinus (S= 13 y α= 2.71. En general, los tipos de vegetación mostraron diferentes especies dominantes y una alta diversidad beta. La composición y estructura de estas comunidades puede asociarse a cambios en altitud y a la perturbación por actividades humanas. No obstante, la zona de estudio aún presenta áreas en buen estado de conservación, particularmente los bosques templados hacia las zonas con mayor altitud, por lo que se sugiere que en un futuro cercano sea incluida dentro de alguna categoría de protección estatal.This study describes composition, structure and diversity of vegetation in the Cerro El Águila, Michoacán. Five plant communities were recognized and for each one all woody individuals ≥10 cm DBH were tallied in sixteen 400 m² circular plots, whereas individuals between 2.5 and 9.9 cm DBH were measured in a 100 m² circular sub-plot centered within each larger plot. A total of 46 species, 33 genera and 21 families were recorded. The tropical deciduous forest and Quercus deserticola forest had low values of mean plant height ( 11 m and basal area (> 40 m²/ha. Diversity was greater in the tropical deciduous forest (S= 23 and α= 5.4, respectively and lower in the oak-pine forest (S= 13 and α= 2.71. All communities displayed

  12. Mineralogy of the silica-epidote mineralized zone (SEMZ) in the Cerro Prieto geothermal reservoir, B.C., Mexico; Mineralogia de la zona mineralizada de silice-epidota (ZMSE) del yacimiento geotermico de Cerro Prieto, B.C., Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo, Georgina; Aragon, Alfonso; Portugal, Enrique; Arellano; Victor M [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Cuernavaca, Morelos (Mexico)]. E-mail: gim@iie.org.mx; Leon, Jesus de; Alvarez, Julio [Comision Federal de Electricidad, B.C. (Mexico)

    2006-07-15

    The distribution of hydrothermal minerals, mineral assemblages and fluid inclusion data were taken from drill cuttings from the production zone of wells all over the Cerro Prieto geothermal field. The production zone has been termed the silica-epidote mineralized zone (SEMZ), and is located in the deep part of the gray shale where thick layers of sandstone are found. Common mineral assemblages show three temperature ranges in the SEMZ: <200 degrees Celsius, 200-250 degrees Celsius and 250-300 degrees Celsius. The first range is characterized by clays, calcite and quartz; the second by quartz, epidote, chlorite and mica, and the third by epidote, amphibole, illite and chlorite. The study of fluid inclusions in authigenic grain quartz has shown two-phase fluid inclusions (liquid + vapor) of different salinities. A wide range exists of homogenization temperatures (Th) and for some wells there is a good agreement between Th and direct temperature measurements. [Spanish] Se determino la distribucion de minerales hidrotermales y las asociaciones parageneticas y se realizo el estudio microtermometrico de inclusiones fluidas a partir de recortes de perforacion de pozos de las distintas areas del campo geotermico de Cerro Prieto. Las muestras de recortes y nucleos de perforacion estudiados provienen de la zona de produccion a la que se le ha denominado Zona Mineralizada de Silice-Epidota (ZMSE), que se encuentra en la parte profunda de la lutita gris con importantes horizontes de areniscas. En esta zona las asociaciones parageneticas mas comunes han mostrado tres intervalos de temperatura para la ZMSE: <200 degrees Celsius, 200-250 degrees Celsius, 250-300 degrees Celsius. El primer intervalo esta caracterizado principalmente por arcillas, calcita y cuarzo; el segundo por cuarzo, epidota, clorita y micas, y el tercero por epidota, anfiboles, illita y clorita. El estudio de inclusiones fluidas en fragmentos de cuarzo autigenico mostro la presencia de inclusiones de dos fases

  13. Studies for recovering injection capacity in wells of the Cerro Prieto, BC, geothermal field; Estudios para recuperar la capacidad de aceptacion en pozos inyectores del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Rosales, Julio [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, Baja California (Mexico)]. E-mail: julio.alvarez@cfe.gob.mx

    2010-01-15

    As in geothermal fields around the world, at Cerro Prieto geothermal field, Baja California, former exploratory and production wells are used to inject residual brine. Since the 1980s, studies and activities have been carried out to find ways to recharge the reservoir and dispose of brine without harming the environment or underground aquifers. These include infiltration and cold-and-hot injection. Some of the studies are presented here, including analyses of litho-facies; core samples; pressure, temperature and spinner logs; well tests and injection rates-plus some studies on the shallow aquifer. All have been useful in fulfilling requirements made by environmental authorities. Because injection rates constantly decrease due to formation damage, it is proposed an additional technique be used to reduce such damages and prolong the lifetime of cold-and-hot injection wells-while ensuring the environment and shallow aquifers are not affected. [Spanish] Al igual que en diversos campos geotermicos en el mundo, en el de Cerro Prieto, Baja California se han utilizado tanto pozos inyectores perforados ex profeso como antiguos pozos exploratorios y productores para inyectar el fluido residual al subsuelo. Desde la decada de los 80 se han realizado diversos estudios y acciones en ese campo geotermico para recargar al yacimiento y para disponer del fluido residual, sin ocasionar danos al ambiente ni a los cuerpos hidricos del subsuelo, que van desde la infiltracion hasta la inyeccion en frio y en caliente. Este articulo presenta los diferentes estudios realizados con ese objetivo en el campo, incluyendo el analisis de litofacies, de nucleos de formacion, de registros de presion, temperatura y spinner, las pruebas en pozos y analisis de tasas de aceptacion, asi como los efectuados en el acuifero superficial. Todos ellos han sido de utilidad para atender los requerimientos de las autoridades ambientales. Finalmente, y en virtud de que las tasas de aceptacion de los pozos

  14. Geological and production analyses focused on exploration of the eastern part of the Cerro Prieto geothermal field, BC; Analisis geologico-productivo enfocado a la exploracion de la parte oriental del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar Dumas, Alvaro [Comision Federal de Electricidad, Residencia General de Cerro Prieto, B.C (Mexico)]. E-mail: alvaro.aguilar@cfe.gob.mx

    2008-01-15

    The eastern part of the Cerro Prieto geothermal field (CGCP), known as Poligono Nuevo Leon, is an area with proven geothermal resources, as confirmed by seven directional wells located toward the east and by vertical well M-200 located inside the polygon. Well M-200 was drilled in 1984 and has produced about 4 million tons of steam to date. It is integrated into the CP-2 sector, producing 68 t/h of steam. Presently the eastern part of CGCP, representing 25% of the total field area, is producing over half of the steam for the entire field. In the last few years, the steam has come only after increasing the number of production wells located in the eastern zone of CGCP (Rodriguez, 2006), where pressure, enthalpy and temperature conditions are better than in other parts of the field. However in the long term it will be necessary to incorporate Poligono Nuevo Leon into the productive area to expand the productive life of CGCP. This paper includes a geological analysis, plus models for steam production, temperature and enthalpy for Poligono Nuevo Leon. [Spanish] La parte oriental del Campo Geotermico de Cerro Prieto (CGCP), conocida como Poligono Nuevo Leon, representa una area potencial con recursos geotermicos comprobados, lo que demuestran siete pozos direccionales que se han perforado hacia el este, asi como el pozo vertical M-200, localizado dentro del poligono. El pozo M-200 se perforo en 1984 y ha producido a la fecha alrededor de 4 millones de toneladas de vapor, estando integrado al sector CP-2 una produccion de 68 t/h de vapor. Actualmente la parte oriental del CGCP, que representa el 25% del area total del campo, produce mas de la mitad del total de vapor del campo. El suministro de vapor en los ultimos anos se ha logrado cubrir aumentando el numero de pozos en operacion localizados en la zona oriente del CGCP (Rodriguez, 2006), ya que es aqui donde hay condiciones de presion, entalpia y temperatura del yacimiento que son mejores que en otras areas del campo

  15. Two-phase characteristics of the feeding fluid of Cerro Prieto IV wells (Mexico) obtained by gas equilibrium; Caracteristicas bifasicas del fluido de alimentacion de pozos de Cerro Prieto IV (Mexico), obtenidas por equilibrio gaseoso

    Energy Technology Data Exchange (ETDEWEB)

    Barragan-Reyes, Rosa Maria; Arellano-Gomez, Victor Manuel; Portugal-Marin, Enrique [Instituto de Investigaciones Electricas (Mexico); De Leon-Vivar, Jesus [Comision Federal de Electricidad, Residencia General de Cerro Prieto, B.C (Mexico)

    2008-10-15

    The gas composition of fluids produced by CP IV geothermal wells from the Cerro Prieto field was studied in order to identify different types of fluids entering the wells by estimating their temperature and excess steam. A method based on the Fischer Tropsch reaction and H2S equilibrium with pyrite-pyrrhotite as mineral buffer (FTHSH3) was used. The results for the reservoir natural state indicated the presence of fluids with heterogeneous reservoir temperature (between 275 and 310 degrees Celsius) and excess steam values, which were found from negative (boiled liquid that has lost steam when flowing to the well) to one (steam phase with zero liquid saturation). The study for individual wells in which boiling processes were identified, showed that through time, the feeding fluids consist of a two-phase mixture with different liquid/steam proportions. Also, the results suggested that a steam phase could occur at CP IV which is added to the feeding fluid, depending on the operation conditions of the wells. The origin of this steam could be the boiling of the deeper liquid due to a pressure drop. [Spanish] Se estudio la composicion gaseosa de los fluidos producidos por pozos geotermicos del sector CP IV del campo de Cerro Prieto para tratar de distinguir aportes de fluidos diferentes mediante la estimacion de su temperatura de yacimiento y del exceso de vapor. Se utilizo un metodo de equilibrio gaseoso basado en la reaccion de Fischer Tropsch y el equilibrio combinado pirita-pirrotita (FT-HSH3). Los resultados obtenidos indican que en el estado inicial del yacimiento existen fluidos que muestran heterogeneidad en los valores de temperatura de yacimiento (entre 275 y 310 grados Celsius), asi como en el exceso de vapor con valores desde negativos (liquido que despues de ebullir ha perdido vapor en su trayecto hacia el pozo) hasta uno (vapor con cero saturacion de liquido). El estudio individual de los pozos con fenomenos de ebullicion muestra que a traves del tiempo

  16. Cerro Grande Fire Impact to Water Quality and Stream Flow near Los Alamos National Laboratory: Results of Four Years of Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    B.M. Gallaher; R.J. Koch

    2004-09-15

    In May 2000, the Cerro Grande fire burned about 7400 acres of mixed conifer forest on the Los Alamos National Laboratory (LANL), and much of the 10,000 acres of mountainside draining onto LANL was severely burned. The resulting burned landscapes raised concerns of increased storm runoff and transport of contaminants by runoff in the canyons traversing LANL. The first storms after the fire produced runoff peaks that were more than 200 times greater than prefire levels. Total runoff volume for the year 2000 increased 50% over prefire years, despite a decline in total precipitation of 13% below normal and a general decrease in the number of monsoonal thunderstorms. The majority of runoff in 2000 occurred in the canyons at LANL south of Pueblo Canyon (70%), where the highest runoff volume occurred in Water Canyon and the peak discharge occurred in Pajarito Canyon. This report describes the observed effects of the Cerro Grande fire and related environmental impacts to watersheds at and near Los Alamos National Laboratory (LANL) for the first four runoff seasons after the fire, from 2000 through 2003. Spatial and temporal trends in radiological and chemical constituents that were identified as being associated with the Cerro Grande fire and those that were identified as being associated with historic LANL discharges are evaluated with regard to impacts to the Rio Grande and area reservoirs downstream of LANL. The results of environmental sampling performed by LANL, the New Mexico Environment Department (NMED), and U.S. Geological Survey (USGS) after the Cerro Grande fire are included in the evaluation. Effects are described for storm runoff, baseflow, stream sediments, and area regional reservoir sediment.

  17. Pucarilla-Cerro Tipillas volcanic complex: the oldest recognized caldera in the southeastern portion of central volcanic zone of Central Andes?

    Energy Technology Data Exchange (ETDEWEB)

    Guzman, Silvina; Petrinovic, Ivan [CONICET -IBIGEO. Museo de Cs. Naturales, Universidad de Salta, Mendoza 2 (4400), Salta (Argentina)], E-mail: guzmansilvina@gmail.com

    2008-10-01

    We recognize the most eastern and oldest collapse caldera structure in the southern portion of the Central Volcanic Zone of the Andes. A description of Middle-Upper Miocene successions related to explosive- effusive events is presented. The location of this centre close to Cerro Galn Caldera attests a recurrence in the volcanism between 12 and 2 Ma in this portion of the Altiplano - Puna Plateau.

  18. Evaluación integral del riesgo volcánico del Cerro Machín, Colombia

    Directory of Open Access Journals (Sweden)

    Leonel Vega Mora

    2013-01-01

    Full Text Available El volcán Cerro Machín (VCM se encuentra situado en la Cordillera Central de Colombia. Por la com- posición química, magnitud y extensión de sus erupciones pasadas, se reconoce como un volcán explosivo de gran potencial de daño, cuya actividad futura podría afectar intensamente durante mucho tiempo (meses hasta años una región muy estratégica para la economía del país, que cubre áreas pertenecientes a los departamentos de Tolima, Quindío, Valle del Cauca y Cundinamarca, en las cuales habitan cerca de un millón de personas. En este artículo se muestra la metodología y resultados del estudio de “Evaluación Integral del Riesgo del Cerro Machín – Colombia”, realizado durante 2009 por el Grupo PIGA de Investigación en Política, Información y Gestión Ambiental de la Facultad de Ingeniería de la Universidad Nacional de Colombia, tomando como punto de partida el estudio de “Evaluación de la Amenaza Volcánica Potencial del Cerro Machín” adelantado en el 2002 por el Servicio Geológico Colombiano (SGC. En consecuencia, se genera y ajusta una nueva ecuación para la determinación del riesgo, basada en la valoración de índices de amenaza intrínseca e índices de vulnerabilidad, los primeros en función del grado de intensidad, duración, extensión y acumulación de las amenazas, y los segundos, en función del grado de exposición espacial y temporal de los elementos (sociales, económicos, institucionales y ecosisté- micos y de su capacidad de respuesta intrínseca y extrínseca ante las amenazas. Con estas ecuaciones y mediante el uso de sistemas de información geográfica (SIG, se realiza para cada escenario de análisis considerando la modelación geoespacial del riesgo a nivel de cada pixel cartográfico del área territorial de estudio. En esta modelación se integra toda la informa- ción territorial del área en estudio, lo que permite obtener, de acuerdo con el marco lógico de evaluación preestablecido

  19. Seismic activity at the Cerro Prieto Geothermal Area (Mexico) from August 1994 to December 1995, and its relationship with tectonics and fluid exploitation

    Science.gov (United States)

    Fabriol, H.; Munguía, L.

    A continuous monitoring of the Cerro Prieto geothermal field was carried out from August 1994 to December 1995 to investigate the seismicity of tectonic origin and the seismicity triggered by exploitation activities. Hypocenters for 148 events were located mainly around the northern end of the Cerro Prieto fault and within the geothermal zone. The estimated focal depths range mostly from 1 to 6 km, for earthquakes with magnitudes from 0.5 to 4.6. It was difficult to distinguish between natural and triggered seismicity. We observed a single case of an earthquake for which a correlation in time and space seems plausible with a sharp increase of fluid injection in a well located at less than 1 km from the epicenter. Fault plane solutions of 26 events with magnitudes between 2.8 and 4.6 indicate right-lateral strike-slip motion for earthquakes that occur near the Cerro Prieto and Imperial faults. Inside the geothermal zone, events with normal components of motion were recorded, as expected from the extensional stress regime of the pull-apart basin laying between both faults.

  20. Chemical variations in the Cerro de Mercado (Durango, Mexico) fluorapatite: Assessing the effect of heterogeneity on a geochronologic standard.

    Science.gov (United States)

    Boyce, J. W.; Hodges, K. V.

    2001-12-01

    Despite the lack of an official pronouncement, the fluorapatite of Cerro de Mercado, Durango, Mexico has become the de facto standard for (U-Th)/He geochronology. In addition to being relatively inclusion-free and easily obtained, these crystals are commonly in excess of 5mm in diameter, permitting the removal of the outer skin of the crystal, theoretically eliminating the alpha-ejection correction. However, bulk analyses of the Durango fluorapatite indicate a substantial variation in U and Th concentrations from aliquot to aliquot (167-238 ppm Th; 9.7-12.3 ppm U, [1]). If similar variations were to occur on the sub-grain scale, small fragments of single crystals could contain helium excesses or deficiencies due to alpha-ejection exchange between zones with varying parent element content. We have performed a series of experiments to quantify the intra-grain variation in U and Th, in order to model the effect of this variation on ages determined on Durango fluorapatite. X-ray maps show concentric zonation in U and Th, with similar, but more apparently pronounced zonation in Si and Cl. Preliminary laser-ablation ICPMS data indicate, not surprisingly, that intra-grain variations in U and Th concentrations obtained by analysis of ~35 μ m spots are larger than that which had been previously obtained by bulk analytical techniques (with overall concentrations greater than for bulk analyses). Thus far, analyses yield U concentrations varying from 11 to 16 ppm, and Th concentrations ranging from 220 to 340 ppm. Modeling underway suggests that parent element variations on the order of 50%, such as those observed, and the resulting differential alpha-exchange could lead to several percent error in age, for ~100 μ m fragments. The effect scales inversely with fragment size, with 300 μ m fragments (roughly the size of a large, single grain analysis) having only ~1% error. This may offer an explanation for the previously observed inability to reproduce ages for the Durango

  1. Geographic Information System (GIS) Emergency Support for the May 2000 Cerro Grande Wildfire, Los Alamos, New Mexico, USA

    Energy Technology Data Exchange (ETDEWEB)

    C.R.Mynard; G.N.Keating; P.M.Rich; D.R. Bleakly

    2003-05-01

    In May 2000 the Cerro Grande wildfire swept through Los Alamos, New Mexico, burning approximately 17,400 ha (43,000 acres) and causing evacuation of Los Alamos National Laboratory (LANL) and the communities of Los Alamos and White Rock. An integral part of emergency response during the fire was the use of geographic information system (GIS) technology, which continues to be used in support of post-fire restoration and environmental monitoring. During the fire Laboratory GIS staff and volunteers from other organizations worked to produce maps and provide support for emergency managers, including at an emergency GIS facility in Santa Fe. Subsequent to the fire, Laboratory GIS teams supported the multiagency Burned Area Emergency Rehabilitation (BAER) team to provide GIS data and maps for planning mitigation efforts. The GIS teams continue to help researchers, operations personnel, and managers deal with the tremendous changes caused by the fire. Much of the work is under the auspices of the Cerro Grande Rehabilitation Project (CGRP) to promote recovery from fire damage, improve information exchange, enhance emergency management, and conduct mitigation activities. GIS efforts during the fire provided important lessons about institutional matters, working relationships, and emergency preparedness. These lessons include the importance of (1) an integrated framework for assessing natural and human hazards in a landscape context; (2) a strong GIS capability for emergency response; (3) coordinated emergency plans for GIS operations; (4) a method for employees to report their whereabouts and receive authoritative information during an evacuation; (5) GIS data that are complete, backed-up, and available during an emergency; (6) adaptation of GIS to the circumstances of the emergency; (7) better coordination in the GIS community; (8) better integration of GIS into LANL operations; and (9) a central data warehouse for data and metadata. These lessons are important for planning

  2. EMPLEO DEL PROGRAMA VOLCFLOW PARA SIMULAR FLUJOS PIROCLÁSTICOS DEL VOLCÁN CERRO MACHÍN, TOLIMA, COLOMBIA

    Directory of Open Access Journals (Sweden)

    Elsa Adriana Cárdenas Quiroga

    2013-01-01

    Full Text Available Se presentan los resultados de simular futuros flujos piroclásticos que podría producir el Volcán Cerro Machín, ubicado en la Cordillera Central de Colombia. Esta simulación se realizó con el programa VolcFlow desarrollado por el Laboratorio de Magmas y Volcanes de la Universidad Blaise Pascal, Francia, diseñado especialmente para modelar el comportamiento de este tipo de productos volcánicos, ya que está basado en las características reológicas de esos flujos. Se comparan las áreas que serían potencialmente afectadas por una erupción de ese tipo y los espesores del material que se depositaría con resultados obtenidos de simulaciones realizadas con un Model Builder desarrollado en ARC GIS por el Grupo de Investigación Geomática Aplicada de la Universidad Militar Nueva Granada en Colombia, obteniéndose resultados similares.

  3. A preliminary interpretation of gas composition in the CP IV sector wells, Cerro Prieto geothermal field, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Barragan Reyes, Rosa Maria; Arellano Gomez, Victor M; Portugal Marin, Enrique [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Morelos (Mexico)]. E-mail: rmb@iie.org.mx; Perez Hernandez, Alfredo; Rodriguez Rodriguez, Marco Helio; Leon Vivar, Jesus de [Comision Federal de Electricidad, Residencia General Cerro Prieto, B.C. (Mexico)

    2007-07-15

    To increase the electrical generation capacity of the Cerro Prieto geothermal field from 620 MW to 720 MW, the Cerro Prieto IV (CP IV) sector of the field was developed in the NE portion of the exploited field. Fourteen new wells have been drilled there since 2000. The wells in CP IV zone produce two-phase fluids at wellhead with heterogeneous steam fraction characteristics: at the central zone and towards the NW, the wells are liquid-dominated while those towards the E and S produce a relatively high steam fraction. This work studies the gas compositions of produced fluids to obtain reservoir parameters such as temperature and steam fraction and identify different sources of fluids in the wells. A method was used based on the Fischer Tropsch reaction and H{sub 2}S equilibria with pyrite-pyrrhotite as a mineral buffer (FT-HSH3). The results for the natural state showed the presence of fluids with reservoir temperatures from 275 to 310 degrees Celsius and excess steam values from -1 to 50%. Data are aligned in a FT-HSH3 trend, suggesting that the well discharges consist of a mixture in different proportions of the two end members. One seems to be a liquid with a temperature of over 300 degrees Celsius with negative or negligible excess steam. The other seems to be a two-phase fluid with a temperature of about 275 degrees Celsius and an excess steam fraction of about 0.5. According to the data for single wells and depending on the production conditions of the wells, reservoir fluid mixtures could occur in different proportions of liquid and steam. Data for 2005 that included wells drilled after 2000 suggest the presence of a steam phase in the reservoir. The steam could be generated with the boiling of deep reservoir fluid from a pressure drop. The mixing trend obtained for the natural state was also seen for 2005 data but lower temperatures (from 265 to 295 degrees Celsius) were obtained compared with those for natural conditions. The entry of lower

  4. Babel en la mina. El campamento minero como modelo de asentamiento en el mundo industrializado: Cerro Muriano (Córdoba.

    Directory of Open Access Journals (Sweden)

    Cano Sanchiz, J.M.

    2012-01-01

    Full Text Available El campamento minero contemporáneo es un tipo de asentamiento muy concreto, configurado bajo unos cánones que, con matices, suelen repetirse a escala internacional. Se trata de un lugar de convergencia, de fricción de clases. También, de un espacio heterogéneo desde el punto de vista cultural donde, sin embargo, el grupo humano formado por los obreros suele aparecer cohesionado por unas circunstancias comunes. Estas características se acentúan allí donde la inversión procede de un país distinto al de la mina. Hablamos, muchas veces, de territorios ocupados en el marco de una actividad económica de corte colonialista. Estas páginas recogen un análisis arqueológico del asentamiento surgido en torno a las minas de Cerro Muriano (Córdoba durante su explotación inglesa a principios del siglo XX. El ejemplo seleccionado nos sirve para ilustrar cómo fueron aquellos campamentos, muchos de los cuales sobrevivieron a la desaparición de la actividad minera y evolucionaron hacia núcleos de población consolidados, como es el caso.

  5. Dieta de murciélagos nectarívoros del Parque Nacional Cerros de Amotape, Tumbes

    Directory of Open Access Journals (Sweden)

    Edith Arias

    2011-07-01

    Full Text Available En el Perú se reporta la presencia de 18 especies de murciélagos nectarívoros, sin embargo se cuenta con poca información sobre la dieta de estas especies. En este estudio se reporta por primera vez la dieta de los nectarívoros Glossophaga soricina, Lonchophylla hesperia y Anoura geoffroyi en el bosque seco ecuatorial y del bosque tropical del Pacífico del Parque Nacional Cerros de Amotape, Tumbes. Analizamos 21 contenidos gastrointestinales e identificamos ocho morfotipos de polen pertenecientes a las familias Bombacaceae, Cactaceae, Fabaceae, Solanaceae, Rubiaceae, Myrtaceae, Malvaceae y Rosaceae. Encontramos evidencia del síndrome de quiropterofilia en Bombacaceae, Cactaceae, Fabaceae, Solanaceae y Rubiaceae. Observamos que A. geoffroyi consume polen de Ceiba trichistandra, Solanaceae y Rubiacea; G. soricina consume de Abutilon reflexum, Armathocereus cartwrightianus, C. trichistandra y Rubiaceae; y L. hesperia de A. cartwrightianus, Eriobotrya japonica, Fabaceae y Psidium sp.; sugiriendo una dieta generalista en estas especies. Los murciélagos G. soricina y A. geoffroyi comparten el consumo del ceibo C. trichistandra y de la Rubiaceae, mientras que G. soricina comparte con L. hesperia el consumo del cactus A. cartwrightianus. Los otros morfotipos de polen no fueron compartidos entre murciélagos. Se encuentra además que el ceibo C. trichistandra fue la especie más consumida, especialmente por G. soricina.

  6. Reproductive structures of Rhamnaceae from the Cerro del Pueblo (Late Cretaceous, Coahuila) and Coatzingo (Oligocene, Puebla) Formations, Mexico.

    Science.gov (United States)

    Calvillo-Canadell, Laura; Cevallos-Ferriz, Sergio R S

    2007-10-01

    Recently discovered fossil flowers from the Cretaceous Cerro del Pueblo and flowers and fruits from the Oligocene Coatzingo Formations are assigned to the Rhamnaceae. The Cretaceous flower, Coahuilanthus belindae Calvillo-Canadell and Cevallos-Ferriz, gen. et sp. nov., is actinomorphic with fused perianth parts forming a slightly campanulate to cupulate floral cup, with sepals slightly keeled and spatulate clawed petals. The Oligocene fossils include Nahinda axamilpensis Calvillo-Canadell and Cevallos-Ferriz, gen. et sp. nov. (characterized by its campanulate bisexual flower with stamens opposite, adnate to and enfolded by petals; and with the ovary ripening into a drupe), and a winged fruit assigned to Ventilago engoto Calvillo-Canadell and Cevallos-Ferriz, sp. nov. The flowers and drupe features indicate closer affinity to Zizipheae and/or Rhamneae, while the single samaroid fruit suggests the presence of Ventilagineae. However, the unique character combination in the fossil flowers precludes placing them in extant genera. Nevertheless, the history of the family is long and can be traced back to the Campanian. A detailed phylogenetic revision of the group that uses morphological characters from both extant and fossil plants is needed to better understand the significance of these records as well as other important fossils of the family.

  7. Effects of pressure drawdown and recovery on the Cerro Prieto beta reservoir in the CP-III area

    Energy Technology Data Exchange (ETDEWEB)

    Truesdell, A.H. [Truesdell (Alfred H.), Menlo Park, CA (United States); Lippmann, M.J. [Lawrence Berkeley National Lab., CA (United States)

    1998-02-01

    The production characteristics of wells in the northwestern Cerro Prieto III area changed greatly when the Cp-III power plant went on line in 1986. Fluid extraction in the field more than doubled and reservoir-wide boiling started immediately, greatly increasing the enthalpy of produced fluids. Some well fluids showed a decrease in chloride due to adiabatic steam condensation in the well and separator, and others were enriched in chloride due to boiling. As reservoir drawdown increased, entrance of cooler and more dilute groundwaters into the reservoir became evident (i.e., condensation stopped, and there was a decrease in enthalpy and chloride in produced fluids). Although some groundwater inflow was from the leaky western margin of the reservoir, the majority is in the northeast, inferred to be local and downward, possibly through more permeable zones associated with the normal fault H. This natural recharge and some reinjection have slowed and possibly reversed pressure drawdown throughout CP-III. Enthalpy has decreased and liquid saturation has increased as the steam-rich zone in the upper part of the reservoir has either disappeared or become thinner.

  8. Monitoring and modeling land subsidence at the Cerro Prieto Geothermal Field, Baja California, Mexico, using SAR interferometry

    Science.gov (United States)

    Carnec, Claudie; Fabriol, Hubert

    Images derived from repeat-pass spaceborne interferometric synthetic aperture radar (InSAR) systems offer the possibility of mapping surface deformation of small spatial extent and monitoring its spatio-temporal evolution. A slow local subsidence has been detected at the Cerro Prieto geothermal field from images acquired by the European Space Agency remote sensing satellites ERS-1/2 between 1993 and 1997. Although agricultural activity in the area limited the investigation, interferometric monitoring revealed that the ground deformation is associated with the withdrawal of geothermal fluid and agreed with the leveling data. Modeling of the subsidence was carried out assuming elastic deformation in a half-space from simple point sources, of which five were necessary to reproduce the fringe patterns observed on the interferograms. The depths and locations of three of the sources are compatible with the location of the known reservoir. The study improves prior knowledge of the displacement field and of the mecanisms involved in the subsidence phenomenon.

  9. Palynological analysis of camelid coprolites: seasonality in the use of the site Cerro Casa de Piedra 7 (Santa Cruz, Argentina)

    Science.gov (United States)

    Velázquez, Nadia Jimena; Burry, Lidia Susana; Fugassa, Martín Horacio; Civalero, María Teresa; Aschero, Carlos Alberto

    2014-01-01

    Palynological, palaeoparasitological and paleobotanical studies of coprolites found in archaeological sites from Perito Moreno National Park (47°57‧S72°05‧W) yielded information on diet, palaeoenvironment and health. These studies allowed adding evidence to the reconstruction of life history of the hunter-gatherers that inhabited Patagonia during the Holocene. We examined the season of the year when camelid Lama guanicoe coprolites (5400 ± 64 yr 14C BP to 9640 ± 190 yr 14C BP) were deposited at Cerro Casa de Piedra 7 (site CCP7). The study used palynological evidence and comparison with pollen spectra of modern feces collected during summer, fall, winter and spring of 2010. The dominant types were: pollen of Nothofagus, Empetrum rubrum, Asteraceae subfam. Asteroideae, Nassauvia, Caryophyllaceae and Poaceae; fern spores; remains of Eimeria macusaniensis; and plant remains of Poaceae, Festuca pallescens, Stipa speciosa, Armeria maritima, Gaultheria mucronata and E. rubrum. Pollen spectra of modern and fossil feces were used for multivariate analysis. Coprolites associated to fall and winter modern feces. These results and those obtained from pollen concentration values and the presence of pollen types indicators of seasonality, allowed the determination of summer, fall and winter coprolites. However, caution must be taken with the seasonality results of coprolites dated earlier than 9000 years BP since the environmental conditions differed from now. The site was probably a camelid shelter during the unfavorable seasons.

  10. The Cerro Bitiche Andesitic Field: petrological diversity and implications for magmatic evolution of mafic volcanic centers from the northern Puna

    Science.gov (United States)

    Maro, Guadalupe; Caffe, Pablo J.

    2016-07-01

    The Cerro Bitiche Andesitic Field (CBAF) is one of the two largest mafic volcanic fields in northern Puna (22-24° S) and is spatially and temporally associated with ignimbrites erupted from some central Andean Altiplano-Puna Volcanic Complex calderas. The CBAF comprises seven scoria cones and widespread high-K calcalkaline lava flows that cover an area of 200 km2. Although all erupted rocks have a relatively narrow chemical range (56-62 % SiO2, 3-6 % MgO), there is a broad diversity of mineral compositions and textures. The least evolved lavas (˜58-61 % SiO2) are high-Mg andesites with scarce (andesites (˜62 wt% SiO2), on the other hand, are porphyritic rocks with plagioclase + orthopyroxene + biotite and ubiquitous phenocryst disequilibrium textures. These magmas were likely stored in crustal reservoirs, where they experienced convection caused by mafic magma underplating, magma mixing, and/or assimilation. Trace element and mineral compositions of CBAF lavas provide evidence for complex evolution of distinct magma batches.

  11. El patrimonio industrial petrolero en la Patagonia: Comodoro Rivadavia (Argentina y Cerro Sombrero (Chile. Una perspectiva comparada

    Directory of Open Access Journals (Sweden)

    Pía Acevedo Méndez

    2016-01-01

    Full Text Available El hallazgo de petróleo en Comodoro Rivadavia (Chubut, Argentina y en Manantiales (Tierra del Fuego, lado chileno, motivó la construcción de espacios socioproductivos bajo el modelo de Company Towns. En el caso argentino la empresa estatal Yacimientos Petrolíferos Fiscales (Y.P.F creó el Campamento Central y la Empresa Nacional del Petróleo (ENAP creó Cerro Sombrero en Chile, los que en la década de 1970 formaron dos tejidos urbanos (barrio en el caso argentino y pueblo en el caso chileno. En esta dinámica se transformó el modo de habitar de ambos espacios, que se convirtieron en potenciales elementos turísticos, teniendo en cuenta que desde el año 2014 poseen reconocimiento patrimonial relacionado con su pasado petrolero y su arquitectura moderna. El objetivo es comparar cómo ambas empresas petroleras estatales construyeron dichos espacios “urbanos” y sus comunidades sociolaborales e indagar en la relación identidad/ patrimonio de ypefeanos y enapinos.

  12. Astronomical orientations in the Iberian oppidum of Cerro de las Cabezas (Valdepeñas, Ciudad Real

    Directory of Open Access Journals (Sweden)

    César Esteban

    2017-01-01

    Full Text Available We present an archaeoastronomical analysis of the orientations observed in the entrance-sanctuary and other enclosures at the Iberian oppidum Cerro de las Cabezas (Valdepeñas, Ciudad Real, Spain, located in the northern Oretania. The most important result of this work is that two of the perimeter walls of the entrance-sanctuary are oriented towards the sunrise, one at the equinoxes and the other at the summer solstice. As in other Iberian sanctuaries, an equinoctial marker is also found. This coincides with the top of one of the most distant mountains of the horizon. The possibility that other walls of the entrance-sanctuary may be oriented to the rising of several of the brightest stars in the sky is also discussed. Moreover, it is found that the east-west axis of the southern part of the oppidum (where an enclosure that some authors have interpreted as a possible sanctuary is located is oriented approximately toward the sunrise at the winter solstice. Finally a possible alignment between the entrance-sanctuary, a necropolis located at the east and the point of the horizon where the sunrise of the winter solstice occurs is also reported.

  13. El frente de corrimiento andino al nivel de los cerros Penitentes y Visera (alta Cordillera de Mendoza: aspectos cronológicos y cartográficos The Andean thrust front in the Cerros Penitentes and Visera (High Cordillera of Mendoza: chronological and cartographic aspects

    Directory of Open Access Journals (Sweden)

    Jean-Claude Vicente

    2009-10-01

    Full Text Available El hallazgo de una iportante fauna de invertebrados marinos del Tithoniano superior a espaldas del cerro Penitentes en la secuencia carbonática basal de la primera escama del frente de corrimiento andino, confirma la lógica tectónica de un despegue de esta unidad a nivel del Yeso Principal y lleva a invalidar ciertas correlaciones litoestratigráficas y bosquejos paleogeográficos asignados a la Formación La Manga. Por otro lado, el análisis de algunos perfiles claves en torno al cerro Penitentes entre la quebrada Vargas y el cerro Visera permite presentar una reinterpretación tectónica del sector. Esta se sustenta en el reconocimiento y la diferenciación de las unidades terciarias básicas representadas por los Conglomerados Penitentes (Mioceno inferior y los Aglomerados Santa María (Mioceno superior en una relación muy similar a la descrita anteriormente al norte de Puente del Inca. El estudio permite seguir las interferencias, en un contexto polifásico, entre las reactivaciones del corrimiento Penitentes de piel fina y un cabalgamiento frontal de piel gruesa que repite la secuencia terciaria. La discordancia entre las secuencias terciarias y el emplazamiento de una klippe de Malm sobre los Conglomerados Penitentes del sinclinal del cerro Visera, conduce a otorgar cierta importancia a la fase del final del Mioceno inferior.The finding of an important marine invertebrate fauna of Upper Tithonian age at the shoulders of the Penitentes hill, in the basal carbonatic sequence of the first Andean wedge confirms the tectonic logic of a detachment of this unit at the level of the Yeso Principal. This allows invalidating certain lithostratigraphic correlations and paleogeographic sketches ascribed to the La Manga Formation. On the other hand, the analysis of some key sections around the Penitentes hill area between the Quebrada de Vargas and the Cerro Visera, allows presenting a tectonic reinterpretation of the sector. This is based on the

  14. ESTRATEGIA DE REMONTAJE APLICADA SOBRE EL REGISTRO CERÁMICO DEL SITIO LOS TRES CERROS 1 (DELTA SUPERIOR DEL RÍO PARANÁ / Refitting applied to pottery from Los Tres Cerros 1 site (Upper Delta of Paraná River

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    Violeta Soledad Di Prado

    2014-12-01

    Full Text Available El sitio arqueológico Los Tres Cerros 1 se encuentra ubicado en el departamento Victoria, Entre Ríos, y consiste en una estructura monticular con una compleja historia ocupacional. La abundancia y fragmentación del registro cerámico del sitio, llevaron a aplicar la estrategia de remontajes, con el propósito de reconstruir la historia de vida de las vasijas e identificar las prácticas humanas y los agentes naturales que actuaron en la configuración del depósito. Sobre una muestra del total de tiestos recuperados en la cuadrícula 1, se realizaron 43 remontajes, que unen fragmentos del mismo nivel y de diferentes niveles. Se identificaron semejanzas en las elecciones técnicas similares (i.e., agregado de tiesto molido, aplicación de pigmento y de surco rítmico efectuadas en distintas etapas del proceso de elaboración del número mínimo de vasijas estimado (NMV= 49. Se reconocieron contenedores utilizados sobre el fuego, posiblemente para la cocción, y piezas probablemente empleadas para servir. Por último, se propusieron hipótesis en torno a la integridad del registro y, al menos para el sector superior de la secuencia estratigráfica, se infirió un evento de ocupación que no fue mayormente disturbado en momentos posteriores al descarte.   Palabras clave: alfarería, remontajes, elecciones tecnológicas, prácticas de uso, procesos de formación de sitio.   Abstract Los Tres Cerros 1 archaeological site is located in Victoria department, Entre Ríos province, and it is a mound with a complex occupational history. The abundance and fragmentation of the ceramic record recovered from this site, led to apply the refitting strategy in order to reconstruct the vessels’ life history and identify human practices and natural agents that took part in the site configuration. From a ceramic sample of the whole recovered in grid 1, 43 reassemblies were made, joining sherds from the same level, as well as from different levels. Similar

  15. PATRONES DE CONSUMO FINAL DE CÉRVIDOS EN EL PARANÁ MEDIO: EL CASO DEL SITIO CERRO AGUARÁ / Cervids final consumption patterns in middle Paraná River: the case of Cerro Aguará archaeological site

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    Leonardo Mucciolo

    2015-06-01

    Full Text Available Los cérvidos fueron amplia y regularmente explotados por los cazadores-recolectores que habitaron la macroregión del Paraná-Plata durante el Holoceno tardío. En la cuenca media del Paraná, sin embargo, muy pocos estudios han enfocado sobre las estrategias empleadas para su obtención, procesamiento y consumo. Teniendo en cuenta esto, el objetivo de este trabajo es explorar dichos aspectos a partir del análisis de los conjuntos de cérvidos provenientes del sitio arqueológico Cerro Aguará, localizado en el departamento General Obligado (provincia de Santa Fe. La perspectiva seleccionada propone al consumo como factor preponderante en la configuración del registro zooarqueológico dentro del continuum de actividades que componen la explotación faunística. Desde esta perspectiva, y tomando en consideración que las carcasas de los cérvidos proveen distintos tipos de recursos alimenticios con diferentes costos de extracción (carne, médula y grasa ósea, se evalúan diferentes indicadores para establecer si existió diferente intensidad en su procesamiento. Los resultados indican que las dos especies de cérvidos identificadas en el sitio, Blastocerus dichotomus y Ozotoceros bezoarticus, ocuparon un rol preponderante en la dieta, aunque las carcasas del primero fueron empleadas más intensivamente probablemente en correlación con su mayor disponibilidad de nutrientes internos, tales como la médula y posiblemente la grasa ósea.  Abstract  Cervids were wide and regularly exploited by several Late Holocene hunter-gatherers inhabiting Paraná Plata macroregion. In the middle Paraná river, however, few research has been made on strategies involving their procurement, processing and consumption. The purpose of this article is to explore those aspects from the analysis of cervid assemblages of Cerro Aguará archaeological site (General Obligado, Santa Fe province. The selected perspective proposes final consumption as one of the most

  16. Analysis of productive evolution of well M-19A, Cerro Prieto geothermal field, BC; Analisis de la evolucion productiva del pozo M-19A del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Rodriguez, Marco H; Romero-Rios, Francisco [Comision Federal de Electricidad, Residencia General de Cerro Prieto, B.C (Mexico)]. E-mail: marco.rodriguez01@cfe.gob.mx

    2007-07-15

    Well M-19A has been the most productive in the Cerro Prieto field, producing around 40 million tons of fluid. The well went on line in February 1975 and was in continuous operation until June 2006. Monthly measurements for over 30 years of operating conditions and chemical and isotopic analyses of the fluids allow identification of the most significant processes occurring in the zone where the well is located. Three dominant recharge types have been identified, each lasting about 10 years. They are a) a recharge of fluids of lower temperature than the production fluids, even though the chemical and isotopic compositions are similar; b) a recharge of lower-temperature fluids with diluted chemical and isotopic compositions; and c) a progressive recharge of reinjected water with a higher chloride concentration and heavy isotopic composition. The production and reinjection rates for over 30 years of production history in the M-19A well zone allow for speculation of a reservoir pressure recovery, which is confirmed with a calculation using production data from well M-19A. The evolution of the reservoir pressure in the zone contrasts with the rest of the reservoir, where a constant pressure drop is observed, particularly toward the central and eastern parts of the field. [Spanish] El pozo M-19A ha sido el mas productivo del campo geotermico de Cerro Prieto, BC, alcanzando una extraccion de mas de 40 millones de toneladas de fluido. Fue integrado a produccion en febrero de 1975 y hasta junio de 2006 ha permanecido en produccion en forma continua. Las mediciones mensuales de sus condiciones operativas y los analisis quimicos e isotopicos del agua producida permiten identificar los procesos mas significativos que han ocurrido a lo largo de esos mas de 30 anos en la zona donde se localiza el pozo. Se han identificado tres tipos de recarga dominantes que se presentan durante un periodo cercano a 10 anos cada uno, los cuales son: a) una recarga de fluidos de menor temperatura

  17. Control estructural de las mineralizaciones de fluorita del batolito Cerro Áspero, Sierras Pampeanas de Córdoba Structural control of vein-type fluorite deposits of Cerro Áspero batholith, Sierras Pampeanas of Córdoba

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    Jorge E Coniglio

    2010-12-01

    Full Text Available Con más de 1.000.000 t de reservas totales el batolito Cerro Áspero, magmatismo devónico de alto potasio, es portador de las mayores concentraciones de fluorita de las Sierras Pampeanas. Las vetas epitermales son de edad cretácica, subverticales, poseen potencias generalmente menores a 3 m y se extienden a profundidades mayores a 200 metros. Ocurren en un área de 440 km² con una distribución intrabatolítica predominante. La geometría y la cinemática de las estructuras mineralizadas son consistentes con deformación por cizalla simple, dextrógira, con el eje extensional principal (σ3 orientado hacia el NNO. Esta situación implantó en el área estructuras extensionales N70ºE ( 4 km de corrida, que presentan patrones de fallas transcurrentes, con bifurcaciones, deflexiones, aperturas, saltos, cierres y fracturas en échelon asociadas. Los estudios texturales y estructurales en las vetas han permitido distinguir cuatro estadios sucesivos de mineralización que fueron controlados por una actividad discontinua de la cupla dextral. Este modelo estructural es similar a aquéllos propuestos para mineralizaciones de fluorita emplazadas en otros sectores del continente durante el mismo período, los que vinculan el control tectónico con la apertura del océano Atlántico sur. El registro del relleno hidrotermal permitió reconstruir la historia de apertura de las estructuras y puede usarse como un criterio efectivo de prospección y exploración. Las mayores concentraciones de mineral ocurren en las estructuras extensionales y en las flexiones dilatantes de las estructuras asociadas con la zona de cizallamiento principal NNE-SSO, que registran la secuencia mineralizada completa.With over 1,000,000 t of total reserves, the high-K devonian granites of the Cerro Áspero batholith (440 km² are the most important fluorite-bearing granitic suite in the Sierras Pampeanas. The epithermal fluorite veins, of Cretaceous age, fill in steeply dipping

  18. Geología de la región del Cerro Guanaquero, Río Diamante, Mendoza

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    Federico Fuentes

    2008-03-01

    Full Text Available El estudio realizado presenta nuevos datos sobre un sector poco conocido de la Cordillera Principal de Mendoza, en la alta cuenca del río Diamante en las adyacencias del cerro Guanaquero, y los primeros datos geocronológicos de sus rocas volcánicas. Las unidades geológicas presentes en el área se dividen en cuatro grupos principales: secuencias sedimentarias mesozoicas marinas y continentales intensamente plegadas y falladas; intrusivos y volcanitas intermedias de edad neógena; rocas volcánicas pliocenas a recientes de composición intermedia a básica, y depósitos cuaternarios inconsolidados. El cerro Guanaquero, un estratovolcán pliocuaternario intensamente erosionado por glaciares pleistocenos, con sus 4.841 metros es el rasgo orográfico más prominente. Está constituido esencialmente por andesitas grises porfíricas, piroxénicas a biotíticas. Intercaladas con las coladas andesíticas se presentan depósitos piroclásticos, aglomerados volcánicos, ignimbritas y basaltos. La datación de una andesita por el método K-Ar en roca total arrojó una edad de 1,4 ± 0,1 Ma. La deformación ándica comenzó en forma de una faja plegada y corrida de piel fina, con pliegues por despegue en el sector occidental y por propagación de falla en el oriental. La compresión al oeste de los 69º47´O terminó por invertir la fallas normales del rift mesozoico. A lo largo de este meridiano se encuentra la falla más importante de la región, la que se ha correlacionado con la falla Malargüe, bien desarrollada en latitudes más australes. Esta falla limita la faja plegada y corrida del Aconcagua, de naturaleza epidérmica, y la faja plegada y corrida de Malargüe, controlada por la inversión tectónica del basamento. El volcanismo fue muy intenso en el Plioceno y el Cuaternario, correspondiendo a un período de empinamiento de la placa oceánica subducida, en el que la región ha sido levantada pasivamente. La alta resistencia a la erosión de

  19. Control estructural de las mineralizaciones de fluorita del batolito Cerro Áspero, Sierras Pampeanas de Córdoba

    Directory of Open Access Journals (Sweden)

    Jorge E Coniglio

    2010-12-01

    Full Text Available Con más de 1.000.000 t de reservas totales el batolito Cerro Áspero, magmatismo devónico de alto potasio, es portador de las mayores concentraciones de fluorita de las Sierras Pampeanas. Las vetas epitermales son de edad cretácica, subverticales, poseen potencias generalmente menores a 3 m y se extienden a profundidades mayores a 200 metros. Ocurren en un área de 440 km² con una distribución intrabatolítica predominante. La geometría y la cinemática de las estructuras mineralizadas son consistentes con deformación por cizalla simple, dextrógira, con el eje extensional principal (σ3 orientado hacia el NNO. Esta situación implantó en el área estructuras extensionales N70ºE ( 4 km de corrida, que presentan patrones de fallas transcurrentes, con bifurcaciones, deflexiones, aperturas, saltos, cierres y fracturas en échelon asociadas. Los estudios texturales y estructurales en las vetas han permitido distinguir cuatro estadios sucesivos de mineralización que fueron controlados por una actividad discontinua de la cupla dextral. Este modelo estructural es similar a aquéllos propuestos para mineralizaciones de fluorita emplazadas en otros sectores del continente durante el mismo período, los que vinculan el control tectónico con la apertura del océano Atlántico sur. El registro del relleno hidrotermal permitió reconstruir la historia de apertura de las estructuras y puede usarse como un criterio efectivo de prospección y exploración. Las mayores concentraciones de mineral ocurren en las estructuras extensionales y en las flexiones dilatantes de las estructuras asociadas con la zona de cizallamiento principal NNE-SSO, que registran la secuencia mineralizada completa.

  20. Hydrothermal-flow regime and magmatic heat source of the Cerro Prieto geothermal system, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Elders, W.A.; Bird, D.K.; Williams, A.E.; Schiffman, P.

    1982-01-01

    This detailed three-dimensional model of the natural flow regime of the Cerro Prieto geothermal field, before steam production began, is based on patterns of hydrothermal mineral zones and light stable isotopic ratios observed in rock samples from more than fifty deep wells, together with temperature gradients, wireline logs and other data. At the level so far penetrated by drilling, this hydrothermal system was heated by a thermal plume of water close to boiling, inclined at 45/sup 0/, rising from the northeast and discharging to the west. To the east a zone of cold water recharge overlies the inclined thermal plume. Fission track annealing studies shows that the reservoir reached 170/sup 0/C only 10/sup 4/ years ago. Oxygen isotope exchange data indicate that a 12 km/sup 3/ volume of rock subsequently reacted with three times its volume of water hotter than 200/sup 0/C. Averaged over the duration of the heating event this would require a flow velocity of about 6 m/year through the pores of a typical cross section of the reservoir having an average porosity of 10%. Although this is an extensional tectonic environment of leaky transform faulting in which repeated intrusions of basalt magma are likely, for simplicity of computation possible heat sources were modelled as simple two dimensional basalt intrusions of various sizes, shapes and locations. We have calculated a series of two-dimensional convective heat transfer models, with different heat sources and permeability distributions. The models which produce the best fit for the temperature distributions observed in the field today have in common a heat source which is a funnel-shaped basalt intrusion, 4 km wide at the top, emplaced at a depth of 5 km to 6 km about 40,000 to 50,000 years ago.

  1. Magmatismo ácido del mioceno superior-cuaternario en el área de Cerro Blanco-La Hoyada, Puna Austral

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    María Carolina Montero López

    2010-11-01

    Full Text Available El volcanismo de composición ácida desarrollado en la Puna Austral entre el Mioceno superior y el Holoceno está representado en el extremo oriental de la cordillera de San Buenaventura (26°25'-27°00'S y 67°25'-67°50' O por dos unidades: Ignimbrita Aguada Alumbrera y Complejo Volcánico Cerro Blanco. Hacia el norte y noroeste de esta área afloran flujos piroclásticos (Ignimbrita Rosada cuyo análisis se presenta aquí a fines comparativos. Estas rocas volcánicas apoyan sobre un basamento metamórfico de mediano a alto grado con intrusivos del Neoproterozoico-Paleozoico inferior y rocas volcánicas de composición intermedia de ca. 9-7 Ma. Las rocas estudiadas abarcan un lapso entre el Mioceno superior (Ignimbrita Aguada Alumbrera e Ignimbrita Rosada hasta el Holoceno (Complejo Volcánico Cerro Blanco, tienen afinidad calcoalcalina y son principalmente de composición riolítica. En este estudio se presentan nuevos datos de campo que permiten ordenar la estratigrafía del sector de estudio, así como resultados de geoquímica. Las ignimbritas del Mioceno Superior-Plioceno estudiadas presentan características similares a las rocas ácidas aflorantes al oeste del área de estudio, las cuales fueron relacionadas por diversos autores a un ambiente de subducción procedentes de fuentes mantélicas con altos porcentajes de contaminación cortical, mientras que el Complejo Volcánico Cerro Blanco podría estar reflejando su procedencia de la fusión directa de la corteza, si bien esta hipótesis debe ser corroborada con mayor cantidad de datos geoquímicos.

  2. [R_Arnedo_SanMiguel] Documentación geométrica de las excavaciones arqueológicas del Cerro de San Miguel (Arnedo, La Rioja)

    OpenAIRE

    2007-01-01

    [ES] El cerro de San Miguel de Arnedo alberga un importante asentamiento plenamente adscrito a la cultura celtibérica. Los restos documentados corresponden a dos conjuntos de viviendas y una estructura defensiva compuesta por un foso y restos de muralla. La documentación se ha realizado mediante estación total. Además, la muralla se ha documentado mediante fotogrametría estereoscópica. [EN] San Miguel’s hill houses an important archaeological site which dates back to the Celtiberian cul...

  3. IMPACTO EN AFLUENTES DEL RÍO PILCOMAYO POR CONTAMINANTES ADICIONALES DE DRENAJE ÁCIDO DE MINAS DESDE CERRO RICO, POTOSÍ-BOLIVIA

    OpenAIRE

    William H.J. Strosnider; Freddy S. Llanos; Cristina E. Marcillo; Ruben R. Callapa; Robert W. Nairn

    2014-01-01

    La minería intensiva y el procesamiento del cuerpo mineralizado del Cerro Rico de Potosí (Bolivia) ha ocurrido desde 1545. Para avanzar la investigación sobre descargas de drenaje acido de minas (DAM) y su conexión a la contaminación río abajo, se generaron datos en dos muestreos durante la temporada más extrema de lluvia y sequía. Las concentraciones en el DAM y arroyos receptores de Ag, B, Ba, Mo, Sb, Se, Sn, y V fueron superiores a los límites de descarga permitidos por la legislación Boli...

  4. Chemical and mineralogical analyses of a weathering mantle developing on peridotite of the mining area for nickel in Cerro Matoso, Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, C.M.; Fabris, J.D. [Departamento de Quimica, UFMG (Brazil)], E-mail: claudiag@dedalus.lcc.ufmg.br, E-mail: fabris@dedalus.lcc.ufmg.br; Pacheco Serrano, W.A. [Departamento de Fisica (Colombia)], E-mail: wpacheco@donato.uptc.edu.co

    1999-11-15

    Four samples were collected at several depths in a weathering mantle developing on peridotite, found in a mining area for nickel of Cerro Matoso, about 20 km southwest of Monte Libano, Department of Cordoba, Colombia. Samples represent the main stratigraphy of the mantle. Powder X-ray diffractometry, RT Moessbauer spectroscopy, saturation magnetization measurements and conventional chemical analysis on the whole and chemically treated samples, and on some of their magnetic extracts, were used to give some details of the main occurring mineralogical phases in the mantle, particular of the magnetic iron oxides.

  5. Tecnología, subsistencia y cronología del sitio El Cerro, Departamento de Río Negro,Uruguaya

    OpenAIRE

    Gascue, Andrés; Loponte, Daniel M.; Moreno, Federica; Bortolotto, Noelia; Rodríguez, Ximena; Figueiro, Gonzalo; Teixeira, Franco; de Acosta, Alejandro

    2016-01-01

    En este trabajo se efectúa una revisión de los materiales obtenidos en El Cerro, excavado por Boretto y colaboradores en la segunda mitad del siglo pasado. El sitio se ubica sobre una suave colina natural en la margen derecha del Río Negro (República Oriental del Uruguay). La estratigrafía observada en sondeos recientemente efectuados en el sitio, indican que se trata de una elevación natural constituida por un albardón de arena edafizada. El conjunto arqueológico fue generado por grupos de c...

  6. Procesos históricos y ambientales en Cerro de San Pedro, San Luis Potosí, México, 1948-1997

    OpenAIRE

    Paula Andrea Martínez Chaves; Alexander Betancourt Mendieta; Miguel Nicolás Caretta; Miguel Aguilar Robledo

    2010-01-01

    Los estudios sobre el municipio Cerro de San Pedro enfatizan la continuidad ambiental aparente que estimula la minería; sin embargo, esta lectura subvalora otras dinámicas que ocurren en la zona. Con base en observaciones directas de trabajo en campo, para realizar análisis de coberturas vegetales, entrevistas con los habitantes de la zona, revisión de cartografía e investigación de archivo, el presente trabajo muestra procesos como la explotación de recursos vegetales y el pastoreo, como act...

  7. Gaseous equilibrium in sector CP IV of the Cerro Prieto, B.C. Mexico geothermal field; Equilibrio gaseoso en el sector CP IV del campo geotermico Cerro Prieto, B.C., Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Barragan Reyes, Rosa Maria; Arellano Gomez, Victor Manuel; Portugal Marin, Enrique [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); De Leon Vivar, Jesus [Comision Federal de Electricidad, Campo Geotermico Cerro Prieto, Cerro Prieto, B. C. (Mexico)

    2007-07-01

    Sector CP IV is located in the NE portion of the Cerrro Prieto geothermal field. The wells of this zone produce two-phase fluids, with different characteristics as far as their steam fraction content; in the central part and towards the NW the fluids are of dominant liquid type whereas towards the E and the S, the fluid contains a relatively higher steam fraction. The results of gaseous equilibrium FT- HSH3 showed that the fluids in the deposit are at temperatures between 275 Celsius degrees and 310 Celsius degrees and contain steam fractions between 0.01 and 0.5. The data found for the natural state are aligned in a tendency defined in the diagram FT- HSH3, that suggest the wells receive different proportions from preexisting steam in the deposit, which are mixed with the liquid phase to produce the observed discharges. The present data, besides showing the presence of deposit steam, also indicates the entrance of lower temperature fluid in the central part of sector CP IV. [Spanish] El sector CP IV se localiza en la porcion NE del campo geotermico Cerro Prieto. Los pozos de esta zona producen fluidos bifasicos, con diferentes caracteristicas en cuanto a su contenido de fraccion de vapor: en la parte central y hacia el NW los fluidos son de tipo liquido dominante mientras que hacia el E y hacia el S, el fluido contiene una fraccion relativamente alta de vapor. Los resultados de equilibrio gaseoso FT-HSH3 mostraron que los fluidos en el yacimiento se encuentran a temperaturas de entre 275 grados Celsius y 310 grados Celsius y contienen fracciones de vapor de entre -.01 y .5. Los datos hallados para el estado natural se alinean en una tendencia definida en el diagrama FT-HSH3, que sugiere que los pozos reciben diferentes proporciones de vapor pre-existente en el yacimiento, que se mezclan con fase liquida para producir las descargas que se observan. Los datos actuales, ademas de mostrar la presencia de vapor de yacimiento, tambien indican la entrada de fluidos de

  8. Geología de la Formación Cerro Negro (Cretácico en Isla Livingston: aportes a su geocronología y contenido paleontológico Geology of the Cerro Negro Formation (Cretaceous in Livingston Island: contributions to its geochronology and paleontological content

    Directory of Open Access Journals (Sweden)

    C.A. Parica

    2007-12-01

    Full Text Available La península Byers se encuentra en el extremo occidental de la isla Livingston, archipiélago de las islas Shetland del Sur. Geológicamente está caracterizada por depósitos marinos, continentales y volcanismo cretácico-terciario que son incluidos en la Formación Cerro Negro de la sección superior del Grupo Byers. Las secuencias magmáticas han sido divididas en dos grupos principales, el primero comprende a las rocas piroclásticas y reúne cinco unidades con un importante desarrollo y distribución en el área. Por su parte, el segundo grupo comprende lavas e intrusivos aflorantes en cerros Don Carlos, Usnea (Usnea Plug, Chester (Chester Cone, Sealer (Sealer Hill y Negro (Negro Hill. Los términos sedimentarios incluyen conglomerados, areniscas y pelitas, de color gris verdoso con estratificación entrecruzada (tanto tabular como en artesa, raramente estratos macizos, laminación horizontal (en algunos casos de naturaleza rítmica, y estructuras de deformación sinsedimentaria (principalmente laminación convoluta. Se propone un ambiente fluvial de depositación, con canales dominados por carga de lecho y barras areno-gravosas bien desarrolladas. En lo que corresponde al sector de planicie de inundación, predominó allí la depositación de material limo-arcilloso por corrientes tractivas débiles durante las crecientes. En las áreas deprimidas de las planicies habría tenido lugar la formación de cuerpos de aguas de poca profundidad en los que se vió favorecida la preservación de la macro y microflora. En las nuevas localidades fosilíferas de península Byers, Domo Rotch (Rotch Dome, cerro Don Carlos, Lomada de las Plantas y 904, ha sido reconocida la presencia de las especies: Araucarites sp., Archangelskya furcata Herbst, Cladophlebis sp., Dictyozamites sp., Elatocladus sp, Phyllopteroides sp., Pseudoctenis sp., Ptyllophyllum menendezii Cantrill, Sphenopteris sp., Eocyathea remesaliae Césari, Sergioa austrina Césari y

  9. TECNOLOGÍA Y SUBSISTENCIA EN EL SITIO ARQUEOLÓGICO CERRO TAPERA VÁZQUEZ (PARQUE NACIONAL PRE-DELTA, REPÚBLICA ARGENTINA

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    Mariano Bonomo

    2014-10-01

    Full Text Available In this paper the results of the studies carried out on ceramic and bone materials recorded at Cerro Tapera Vázquez site (Argentinean Northeast are presented. Taxonomic, anatomic and taphonomic studies of bone assemblages and technological-decorative analysis and refitting of pottery were undertaken. The site is located on a mound next to El Ceibo Creek, where 16 m2 were excavated in 2008. Abundant smooth, incised and modeled pottery (handles and zoomorphic appendages and numerous bones remains of Myocastor coypus (most frequent taxon, Blastocerus dichotomus, Ozotoceros bezoarticus, Cavia aperea, Leopardus geoffroyi, Lycalopex gymnocercus, Hydrochaeris hydrochaeris, birds and fish (Siluriformes and Characiformes were recorded. Except Cavia aperea rodent and Dusicyon gimnocercus fox, all taxa show evidence of anthropic modification (cut marks, fresh fractures and burning. Two radiocarbon dates were obtained: 650 and 520 yrs. BP. The results reached in this study lead to the conclusion that the pre-Hispanic populations that occupied Cerro Tapera Vázquez by the end of the Late Holocene were riverine canoe peoples, with complex ceramic technology and subsistence based on hunting of coypu, capybara and cervids, fishing and small-scale horticulture.

  10. Geochemistry of the Neoproterozoic (800-767 Ma) Cerro Bori orthogneisses, Dom Feliciano Belt in Uruguay: tectonic evolution of an ancient continental arc

    Science.gov (United States)

    Lenz, C.; Porcher, C. C.; Fernandes, L. A. D.; Masquelin, H.; Koester, E.; Conceição, R. V.

    2013-10-01

    The Cerro Bori orthogneisses, crystallized between ca. 800 and 767 Ma, are composed of a sequence of mafic gneisses, with dioritic-gabbroic and dioritic composition tectonically interleaved with a sequence of tonalitic and granodioritic gneisses. These rocks intruded the Chafalote paragneisses (metapelites, semipelites, carbonate and mafic rocks) and they were metamorphosed of high P-T conditions at ca. 676-654 Ma. This paper presents the first major and trace geochemical signatures, as well as Sm and Pb isotopic composition for the Cerro Bori orthogneisses, which allow distinguishing three different groups of rocks. Type I rocks are mafic gneisses with tholeiitic affinity, whereas the Type II rocks are tonalitic and granodioritic gneisses with calc-alkaline affinity. The third type is composed of biotite-rich mafic gneisses with potassic and ultrapotassic affinities. All the three types of rocks have negative ℰND values (between -2.12 and -6.67) and old TDM ages (between 1.2 and 2.0 Ga), indicating that the process of crustal assimilation/contamination was an important process, together with fractional crystallization. An continental arc tectonic setting is suggested to this association of rocks between 800 and 767 Ma. This subduction suggests the existence of an ocean between Rio de La Plata and adjacent cratons during the break up of the Rodinia supercontinent.

  11. ANALISIS DEL CO-TRATAMIENTO PASIVO DE AGUAS RESIDUALES MUNICIPALES Y DRENAJE ACIDO DE MINAS EN CERRO RICO DE POTOSÍ, BOLIVIA

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    William H.J. Strosnider

    2015-01-01

    Full Text Available El drenaje acido de minas (DAM es un problema a nivel mundial. El co-tratamiento pasivo de DAM con aguas residuales municipales (ARM es una manera efectiva y de bajo costo que utiliza los nutrientes de ARM para tratar las concentraciones de metales y sulfato en DAM. Cerro Rico de Potosí, Bolivia es una de las grandes ciudades mineras en el mundo que tiene muchos problemas con el DAM. El objetivo de este estudio fue determinar velocidades de reacción de Al, Fe, Mn, Zn, y otros metales en DAM provenientes de un flujo de agua en Cerro Rico usando un sistema reactor de tres etapas. El DAM tenía un pH de 3.58, acidez de 1080 mg/L equivalente a CaCO3 conteniendo concentraciones de 12, 68, 17, y 550 mg/L de Al, Fe, Mn y Zn respectivamente. Las velocidades de reacción de Al, Fe, Mn y Zn fueron de 1.43, 2.09, 0.01 y 0.10 d-1, respectivamente.

  12. Edad, caracterización petrográfica y Geoquímica del Granitoide del Cerro Falkner, Neuquén

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    Sabrina Crosta

    2008-03-01

    Full Text Available El Cerro Falkner se halla constituido por rocas graníticas infrayacentes a las volcanitas de la Formación Ventana de edad paleógena. Dichos intrusivos son de composición granodiorítica, metaluminosos a peraluminosos, subalcalinos, con características de granitos de arco volcánico concordantes con otros granitoides del segmento norte de la Cordillera Patagónica Septentrional. La edad obtenida por el método K-Ar sobre anfíboles de composición tschermakítica (125 ± 20 Ma indica una edad mínima perteneciente al Cretácico inferior para la granodiorita del cerro Falkner, por lo que sería incorrecto utilizar la denominación Formación Los Machis (Cretácico superior para estas rocas. Esta edad, permite vincular las rocas graníticas del área de estudio con el volcanismo representado por el Grupo Divisadero de edad predominantemente cretácica inferior.

  13. Rock-magnetism and ore microscopy of the magnetite-apatite ore deposit from Cerro de Mercado, Mexico

    Science.gov (United States)

    Alva-Valdivia, L. M.; Goguitchaichvili, A.; Urrutia-Fucugauchi, J.; Caballero-Miranda, C.; Vivallo, W.

    2001-03-01

    Rock-magnetic and microscopic studies of the iron ores and associated igneous rocks in the Cerro de Mercado, Mexico, were carried out to determine the magnetic mineralogy and origin of natural remanent magnetization (NRM), related to the thermo-chemical processes due to hydrothermalism. Chemical remanent magnetization (CRM) seems to be present in most of investigated ore and wall rock samples, replacing completely or partially an original thermoremanent magnetization (TRM). Magnetite (or Ti-poor titanomagnetite) and hematite are commonly found in the ores. Although hematite may carry a stable CRM, no secondary components are detected above 580°, which probably attests that oxidation occurred soon enough after the extrusion and cooling of the ore-bearing magma. NRM polarities for most of the studied units are reverse. There is some scatter in the cleaned remanence directions of the ores, which may result from physical movement of the ores during faulting or mining, or from perturbation of the ambient field during remanence acquisition by inhomogeneous internal fields within these strongly magnetic ore deposits. The microscopy study under reflected light shows that the magnetic carriers are mainly titanomagnetite, with significant amounts of ilmenite-hematite minerals, and goethite-limonite resulting from alteration processes. Magmatic titanomagnetites, which are found in igneous rocks, show trellis, sandwich, and composite textures, which are compatible with high temperature (deuteric) oxy-exsolution processes. Hydrothermal alteration in ore deposits is mainly indicated by martitization in oxide minerals. Grain sizes range from a few microns to >100 mm, and possible magnetic state from single to multidomain, in agreement with hysteresis measurements. Thermal spectra, continuous susceptibility measurements, and IRM (isothermal remanent magnetization) acquisition suggest a predominance of spinels as magnetic carriers, most probably titanomagnetites with low

  14. Effect of artificial feeders on pollen loads of the hummingbirds of Cerro de la Muerte, Costa Rica.

    Science.gov (United States)

    Avalos, Gerardo; Soto, Alejandra; Alfaro, Willy

    2012-03-01

    Although sugar-water feeders are commonly used by enthusiasts to attract hummingbirds, little is known about how they affect hummingbird behavior and flower use. We studied the highland hummingbird assemblage of Cerro de La Muerte, Costa Rica, both at a site with permanent feeders (La Georgina Restaurant) and further from it. We examined how feeder use and monopolization affected seasonal changes in pollen loads during four sampling periods, including dry and wet seasons, from 2003-2005. We expected that species monopolizing the feeders would carry little or no pollen whatsoever, and would have pollen loads characterized by low floral diversity, in contrast with species less dependent on feeders. We obtained pollen samples from 183 individuals of four hummingbird species captured around the feeders using mist nets, which were compared with a pollen reference collection of plants with a pollination syndrome by hummingbirds. The same methods were implemented at a site 3km away from the feeders. Feeder usage was quantified by counting the number of times hummingbirds drank from the feeders in periods of 4min separated by 1min. The effects of hummingbird species and season on pollen load categories were assessed using a nominal logistic regression. The alpha species at the site, the Fiery-throated Hummingbird (Panterpe insignis), dominated the feeders during the dry season. Meanwhile, in the wet season, feeder usage was more evenly distributed across species, with the exception of the Volcano Hummingbird, Selasphorus flammula, which occupies the last place in the dominance hierarchy. Pollen loads of hummingbirds captured near feeders were low in abundance (more than 50% of captured individuals had zero or low pollen loads), and low in species richness (96% of the hummingbirds with pollen from only one plant genus, Centropogon). Overall pollen loads increased during the dry season coinciding with peaks in flower availability, although the majority of captured

  15. Recycling of water, carbon, and sulfur during subduction of serpentinites: A stable isotope study of Cerro del Almirez, Spain

    Science.gov (United States)

    Alt, Jeffrey C.; Garrido, Carlos J.; Shanks, Wayne C.; Turchyn, Alexandra; Padrón-Navarta, José Alberto; López Sánchez-Vizcaíno, Vicente; Gómez Pugnaire, María Teresa; Marchesi, Claudio

    2012-01-01

    We use the concentrations and isotope compositions of water, carbon, and sulfur in serpentinites and their dehydration products to trace the cycling of volatiles during subduction. Antigorite serpentinites from the Cerro del Almirez complex, Spain, contain 9–12 wt.% H2O and 910 ± 730 ppm sulfur, and have bulk δ18O values of 8.6 ± 0.4‰, δD = − 54 ± 5‰, and δ34S = 5.0‰, consistent with serpentinization at temperatures of ~ 200 °C by seawater hydrothermal fluids in a seafloor setting. The serpentinites were dehydrated to chlorite–harzburgite (olivine + orthopyroxene + chlorite) at 700 °C and 1.6–1.9 GPa during subduction metamorphism, resulting in loss of water, and sulfur. The chlorite–harzburgites contain 5.7 ± 1.9 wt.% H2O, and have bulk δ18O = 8.0 ± 0.9‰, and δD = − 77 ± 11‰. The rocks contain 650 ± 620 ppm sulfur having δ34S = 1.2‰. Dehydration of serpentinite resulted in loss of 5 wt.% H2O having δ18O = 8–10‰ and δD = − 27 to − 65‰, and loss of 260 ppm sulfur as sulfate, having δ34S = 14.5‰. The contents and δ13C of total carbon in the two rock types overlap, with a broad trend of decreasing carbon contents and δ13C from ~ 1300 to 200 ppm and − 9.6 to − 20.2‰. This reflects mixing between reduced carbon in the rocks (210 ppm, δ13C ≈ − 26‰) and seawater-derived carbonate (δ13C ≈ − 1‰). Our results indicate: 1) Serpentinized oceanic peridotites carry significant amounts of isotopically fractionated water, carbon and sulfur into subduction zones; 2) Subduction of serpentinites to high P and T results in loss of water, and sulfur, which can induce melting and contribute to 18O, D, and 34S enrichments and oxidation of the sub-arc mantle wedge; and 3) Isotopically fractionated water, carbon, and sulfur in serpentinite dehydration products are recycled deeper into the mantle where they can contribute to isotope heterogeneities and may be significant for volatile budgets of the deep Earth.

  16. MUCHO MÁS QUE SÓLO APROVISIONAMIENTO LÍTICO: ACTIVIDADES EN CANTERAS Y PRÁCTICAS SOCIALES EN LAS FUENTES DE PAMPA OESTE, QUEBRADA SECA Y PUNTA DE LA PEÑA (ANTOFAGASTA DE LA SIERRA, CATAMARCA / Much more than just lithic procurement: activities at quarrie

    Directory of Open Access Journals (Sweden)

    Federico Miguel Bobillo

    2015-06-01

    Full Text Available En este trabajo se abordan las canteras y talleres asociados de Punta de la Peña, Quebrada Seca y Pampa Oeste, en Antofagasta de la Sierra (Catamarca, con el objeto de explorar la multiplicidad de actividades y prácticas sociales involucradas en la utilización de dichas fuentes. Se trata de tres fuentes de vulcanitas intensamente explotadas a lo largo de la secuencia prehispánica del área. De esta forma, se toma a las canteras no sólo como un depósito de rocas útiles para la subsistencia, sino como un escenario social donde confluyen y se materializan diferentes prácticas y expresiones sociales. Así, a la explotación de las rocas se suman toda una serie de tareas vinculadas, por ejemplo, con prácticas de enseñanza/aprendizaje y actividades de subsistencia, procesamiento/consumo y rituales. Esta aproximación considera a las canteras desde una perspectiva orientada a abordar las elecciones y prácticas llevadas a cabo por los agentes en contextos de aprovisionamiento, partiendo de la base de que estos actúan desarrollando una diversidad de actividades conectadas en torno a la apropiación de un recurso específico.Abstract  Quarries and workshops at Punta de la Peña, Quebrada Seca and Pampa Oeste (Antofagasta de la Sierra, Catamarca are considered in this paper. The goal is to explore the multiplicity of social activities and practices involved in the use of these quarries. These three vulcanite sources were intensively exploited during the pre-Hispanic history of the region. In this way, quarries are not only considered rock deposits useful for subsistence, but also a social scenario where different social practices and social expressions converge and are materialized. Thereby, series of linked tasks are added to rock exploitation. For example, teaching/learning practices and subsistence, processing/consumption and ritual activities. This approach considers quarries from a perspective oriented to the analysis of elections and

  17. UN ENCUENTRO DE ARQUEOLOGÍAS: RESCATES Y ESTUDIO DE COLECCIONES DEL INICIO DEL PERÍODO TARDÍO (CA. SIGLOS XI-XIII (CATAMARCA, ARGENTINA / An encounter of archaeologies: rescues and study of collections of the Late Period beginning (ca. XI-XIII centuries

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    Valeria Palamarczuk

    2015-12-01

    Full Text Available Se expone una estrategia de trabajo en la que convergen dos líneas de la práctica arqueológica actual: los rescates arqueológicos y el estudio de colecciones de museos. Luego de una breve presentación de la categoría arqueológica “Hualfín”, se presentan tres rescates de entierros en “urnas Hualfín”, realizados en el marco de estudios de impacto arqueológico en las localidades de Los Nacimientos y La Ciénaga del Medio, en el valle de Hualfín, provincia de Catamarca. Las tres urnas son comparadas, mediante un ejercicio de morfometría estadístico, con una muestra de 77 urnas “Hualfín” y “Shiquimil” relevadas en museos. Los ejemplares que componen la muestra provienen de los valles de Hualfín, Yocavil, del Cajón y Andalgalá. La comparación con la base de datos contribuye a la contextualización regional de las urnas rescatadas y a la observación de tendencias estéticas compartidas con el conjunto. Los tres fechados radiocarbónicos obtenidos por AMS permiten ubicar a los eventos funerarios entre los siglos XI y XII y aportan a la discusión sobre la cronología del conjunto.  AbstractWe present a working strategy which integrates two lines in the current archaeological practice: archaeological rescues and study of museum collections. After a brief presentation of the archaeological category "Hualfín" three burials rescues in "Hualfín urns" are presented. The rescues were carried out in the frame of archaeological impact studies made in the towns of Los Nacimientos and La Cienega del Medio, in the Hualfín valley, Catamarca province. The three urns are compared, by a statistical morphometric exercise, with a sample of 77 "Hualfín" and "Shiquimil" urns registered in museums. The specimens come from the valleys of Hualfín, Yocavil, el Cajón and Andalgalá. The comparison with the database contributes to the regional contextualization of the three findings and to the observation of aesthetic trends shared with

  18. Analysis of two catalogues of seismicity at the Cerro Prieto geothermal area (Baja California) from 1988 to 1995, relationship with reinjection; Analisis de dos catalogos de sismicidad en el area geotermica de Cerro Prieto (Baja California) de 1988 a 1995, relacion con la reinyeccion

    Energy Technology Data Exchange (ETDEWEB)

    Fabriol, Hubert [Centro de Investigacion y de Ensenanza Superior de Ensenada (CICESE), Ensenada (Mexico)

    1996-09-01

    In order to study the effects of fluid reinjection in the Cerro Prieto geothermal field, started in 1989, seismicity recorded in this area and included in the USGS-Caltech (California Technology) (US) and the Red Sismologica del Noreste de Mexico (RESNOM) of the Centro de Investigacion Cientifica y de Ensenanza Superior (CICESE, Mexico) catalogues is reviewed since 1988. The precision of determination of epicenters is compared with the location of moderate events recorded by a local array, setup around Cerro Prieto since August 1994. We note a bias in both catalogues, as events located by USGS-Caltech are shifted between 5 to 10 km towards south and events of RESNOM are shifted between 4 to 8 km towards northeast. That limits the use of these catalogues for precise studies of reinjection effects in the geothermal field. Seismic activity is low until 1991 and increases afterwards, particularly in 1993 and 1995. Comparison of USGS-Caltech catalogue with changes in reinjection flow rates show at beginning of 1995 only one example of short-range effect between reinjection and seismicity (but using the epicenter determination of the local network) and possibly several medium-range effects (between 6 and 8 months). In that case, the flow rate increase corresponding to the beginning of winter, could be followed by one or more events of magnitude ranging from Ml=3 to Ml=4 during midsummer. Taking into account the tectonic context of the area, it is also possible that those event could be associated either to Cerro Prieto fault or to the spreading center source of the thermal anomaly. The continuous monitoring with a local network will allow to precise those preliminary results, obtained with regional networks. [Espanol] Como parte del estudio sobre los efectos de la reinyeccion de fluido en el campo geotermico de Cerro Prieto, iniciado en 1989, se analiza de manera critica la sismicidad registrada en el area y reportada en los catalogos de USGS-Caltech (Tecnologico de

  19. Mapping the edge of the Cerros del Rio volcanic field, New Mexico: a piece of the puzzle to understanding a potential geothermal resource

    Science.gov (United States)

    Pellerin, L.; Gallegos, M.; Goebel, M.; Murphy, B. S.; Smith, J.; Soto, D.; Swiatlowski, J.; Volk, C.; Welch, M.; Feucht, D. W.; Hollingshaus, B.; Bedrosian, P. A.; McPhee, D. K.

    2012-12-01

    The Cerros del Rio volcanic field located west of Santa Fe, New Mexico spans the southwestern part of the Espanola Basin with the Rio Grande to the west. Underlying the volcanics are the Santa Fe Group sediments, which contain the Ancha Formation, an important aquifer in the region. High temperature gradients in water wells reveal a potential geothermal prospect. In 2012 the Summer of Applied Geophysical Experience (SAGE) program acquired transient electromagnetic (TEM), audiomagnetotelluric (AMT), gravity and ground magnetic data to determine the buried eastern margin of the volcanic field and the connectivity related to the underlying sediments. The roughly EW 5-km long transect was sited from USGS aeromagnetic data to cross the boundary of the Cerros del Rio volcanic field. TEM data collected at ten stations, at 200-400 m spacing, along the transect employed an in-loop configuration with a square 100 m x 100 m transmitter loop and both a Zonge receiver coil and a 5 m square receiver loop. The 5 m loop allowed for the recovery of early-time data that was saturated when using the Zonge coil. AMT data were acquired at eight stations, at 400-500 m spacing, using the Geometric Stratagem system recording from 92 kHz to 10 Hz; a horizontal magnetic dipole transmitter was used to augment low signal strength at around 1 kHz. Gravity data along the profile were acquired using CG-3 and CG-5 Scintrex gravimeters with a station interval >250 m. Magnetic data were acquired with a Geometrics Cesium vapor G-858 magnetometer for about 3500 m along the profile at a 0.5 second sampling rate. Two volcanic flows interbedded with Ancha Formation and overlying Santa Fe Group sediments were identified in both the TEM and AMT modeling. High surface resistivity zones (>300 ohm-m) with depths ranging from ~100 to 300 m define the volcanic flows and correspond to high densities (2.3 to 2.55 g/cm3), while low resistivity zones (<30 ohm-m) correspond to lower densities (~2.1 g/cm3). High

  20. Operation and Performance of a Biphase Turbine Power Plant at the Cerro Prieto Geothermal Field (Final Report)

    Energy Technology Data Exchange (ETDEWEB)

    Hays, Lance G. [Douglas Energy Company, Placentia, CA (United States)

    2000-09-01

    A full scale, wellhead Biphase turbine was manufactured and installed with the balance of plant at Well 103 of the Cerro Prieto geothermal resource in Baja, California. The Biphase turbine was first synchronized with the electrical grid of Comision Federal de Electricidad on August 20, 1997. The Biphase power plant was operated from that time until May 23, 2000, a period of 2 years and 9 months. A total of 77,549 kWh were delivered to the grid. The power plant was subsequently placed in a standby condition pending replacement of the rotor with a newly designed, higher power rotor and replacement of the bearings and seals. The maximum measured power output of the Biphase turbine, 808 kWe at 640 psig wellhead pressure, agreed closely with the predicted output, 840 kWe. When combined with the backpressure steam turbine the total output power from that flow would be increased by 40% above the power derived only from the flow by the present flash steam plant. The design relations used to predict performance and design the turbine were verified by these tests. The performance and durability of the Biphase turbine support the conclusion of the Economics and Application Report previously published, (Appendix A). The newly designed rotor (the Dual Pressure Rotor) was analyzed for the above power condition. The Dual Pressure Rotor would increase the power output to 2064 kWe by incorporating two pressure letdown stages in the Biphase rotor, eliminating the requirement for a backpressure steam turbine. The power plant availability was low due to deposition of solids from the well on the Biphase rotor and balance of plant problems. A great deal of plant down time resulted from the requirement to develop methods to handle the solids and from testing the apparatus in the Biphase turbine. Finally an online, washing method using the high pressure two-phase flow was developed which completely eliminated the solids problem. The availability of the Biphase turbine itself was 100

  1. Jurassic tetrapods and flora of Cañadón Asfalto Formation in Cerro Cóndor area, Chubut Province Flora y tetrápodos del Jurásico de la Formación Cañadón Asfalto en el área de Cerro Cóndor, provincia de Chubut

    OpenAIRE

    2008-01-01

    The plant and tetrapod fossil record of the Cañadón Asfalto Formation (Middle to Late Jurassic) found in Cerro Cóndor area (Chubut Province) is summarized here. The flora is dominated by conifers (Araucariaceae, Cupressaceae sensu lato) but also includes ferns and equisetaleans. The tetrapod fauna is composed of dinosaur taxa described in the 70's as well as other remains recently described and other vertebrate groups such as amphibians, turtles, and mammals. The amphibian remains have been i...

  2. Al Este del Cerro Pampa: ampliación del área de disponibilidad de obsidiana de la Pampa del Asador (Provincia de Santa Cruz East of the Cerro Pampa: enlargement of the obsidian availability area from Pampa del Asador (Santa Cruz Province

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    Juan Bautista Belardi

    2006-12-01

    Full Text Available La Pampa del Asador ha sido identificada como el lugar de proveniencia de distintos tipos de obsidiana, mayoritariamente negra, y el Cerro Pampa, ubicado en el extremo suroeste de la pampa, ha sido un punto central a partir del cual se ha medido la dispersión de los artefactos confeccionados en esta materia prima. Sobre la base de la interpretación de imágenes satelitales, análisis químicos y trabajos de campo se presenta y discute la evidencia provista por nódulos y artefactos de obsidiana recuperados en paleocauces y un abanico aluvial que se origina en la Pampa del Asador. Los resultados muestran la ampliación del área de disponibilidad de obsidiana 65 km hacia el este y 75 km al noreste del Cerro Pampa y, aunque presentando menor frecuencia relativa de nódulos y el decrecimiento de sus tamaños, el área se amplía a lo largo de la Pampa La Chispa. Estos resultados tienen implicaciones tanto en términos de la distribución de frecuencias de artefactos de obsidiana en el registro arqueológico regional como en los costos de aprovisionamiento de la roca.Pampa del Asador has been identified as the source of distinct types of obsidian (generally black, and Cerro Pampa, located in the extreme southwest of the Pampas, has been the central point from which the dispersal of artifacts fashioned from this obsidian has been measured. Based on the interpretation of satellite images, geochemical analysis, and field work, we present and discuss evidence provided by nodules and artifacts of obsidian recovered from paleo-drainage channels and an alluvial fan which originates in Pampa del Asador. The results expand the area of availability of obsidian 65 km east and 75 km northeast of Cerro Pampa, and also across Pampa La Chispa, although the relative frequency of nodules decreases and smaller size increases. These results have implications both in terms of the distribution and frequency of obsidian artifacts in the regional archaeological record

  3. El sitio Bajo del Coypar II: Las evidencias más tempranas (CA. 1000 AP del proceso agropastoril en la Puna Meridional Argentina (Antofagasta de la Sierra, Catamarca

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    Silvina Vigliani

    2005-01-01

    Full Text Available El sitio Bajo del Coypar II (BC II es un conjunto de estructuras de pequeñas dimensiones ubicado sobre una saliente de la ladera de los cerros del Coypar, frente y alrededor del cual se distribuye una gran superficie de campos de cultivo prehispánicos, (Bajo del Coypar I de aproximadamente 1000 ha. En un trabajo anterior se postuló que este amplio sistema de producción agrícola se originó hacia el final del proceso regional tardío (ca. 1300 AP en asociación con el crecimiento del principal centro habitacional de la región, La Alumbrera (Olivera et.al, 1994 y que luego fue apropiado y ampliado por el Incario. En el presente trabajo se plantean tres objetivos generales: conocer el tipo de actividades que se realizaban en el conjunto de estructuras de BC II, establecer la asociación que había entre este conjunto de estructuras y el sistema de producción agrícola e identificar posibles cambios en el uso del espacio a lo largo del tiempo. En un principio se pensó que Bajo del Coypar II formaba parte de la ampliación del espacio productivo implementada por el Imperio Incaico. Las investigaciones llevadas a cabo en el mismo permitieron determinar que efectivamente hacia las etapas más tardías y en asociación con el Incario había una estrecha relación con el sector agrícola, evidenciado en una alta frecuencia de vasijas para el almacenaje y/o el procesamiento de sustancias secas. Sin embargo, también revelaron ocupaciones más tempranas vinculadas a grupos o unidades domésticas con un desarrollo creciente de las prácticas agrícolas. De este modo, la actividad agro-pastoril fue, en este sector de la Puna meridional, mucho más temprana de lo que pensábamos.

  4. Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: A telescoped low-pressure, low-temperature metamorphic facies series

    Science.gov (United States)

    Schiffman, P.; Elders, W. A.; Williams, A. E.; McDowell, S. D.; Bird, D. K.

    1984-01-01

    In the Cerro Prieto geothermal field, carbonate-cemented, quartzofeldspathic sediments of the Colorado River delta are being actively metasomatized into calc-silicate metamorphic rocks by reaction with alkali chloride brines between 200 and 370 °C, at low fluid and lithostatic pressures and low oxygen fugacities. Our petrologic investigations of drill cores and cuttings from more than 50 wells in this field identified a prograde series of zones that include as index minerals wairakite, epidote, prehnite, and clinopyroxene. Associated divariant mineral assemblages are indicative of a very low pressure, low-temperature metamorphic facies series spanning the clay-carbonate, zeolite, greenschist, and amphibolite facies. This hydro-thermal facies series, which is now recognized in other active geothermal systems, is characterized by temperature-telescoped dehydration and decarbonation. Its equivalent can now be sought in fossil hydrothermal systems.

  5. Recent Vertical Deformation in Mexicali Valley and its Relationship with Tectonics, Seismicity, and the Exploitation of the Cerro Prieto Geothermal Field, Mexico

    Science.gov (United States)

    Glowacka, E.; González, J.; Fabriol, H.

    The interpretation of the results of regional and local leveling which began in 1977 in the Mexicali Valley and the local short profile precision leveling which started in 1994 are discussed. The relation of vertical deformations around the Cerro Prieto Geothermal Field (CPGF) and along the Imperial fault, with local tectonics and seismicity in the Mexicali Valley, is reviewed. Also the relation between vertical deformation and fluid operation in the CPGF is analyzed. The subsidence observed in the field seems to be induced by fluid extraction. The way in which fluid production influences surface changes along the Imperial fault is not clear. The possibility that seismicity is triggering subsidence in the area and vertical movement on the Imperial fault is discussed.

  6. Contrasting compositional trends of rocks and olivine-hosted melt inclusions from Cerro Negro volcano (Central America): implications for decompression-driven fractionation of hydrous magmas

    Science.gov (United States)

    Portnyagin, Maxim V.; Hoernle, Kaj; Mironov, Nikita L.

    2014-10-01

    Melt inclusions in olivine Fo83-72 from tephras of 1867, 1971 and 1992 eruptions of Cerro Negro volcano represent a series of basaltic to andesitic melts of narrow range of MgO (5.6-8 wt %) formed by ~46 wt % fractional crystallization of olivine (~6 wt %), plagioclase (~27 wt %), pyroxene (~13 wt %) and magnetite (high-Mg basalts reflects the process of phenocryst re-distribution in progressively evolving melt. The crystallization scenario is anticipated to operate everywhere in dykes feeding basaltic volcanoes and can explain the predominance of plagioclase-rich high-Al basalts in island arc as well as typical compositional variations of magmas during single eruptions.

  7. Procesos históricos y ambientales en Cerro de San Pedro, San Luis Potosí, México, 1948-1997

    Directory of Open Access Journals (Sweden)

    Paula Andrea Martínez Chaves

    2010-01-01

    Full Text Available Los estudios sobre el municipio Cerro de San Pedro enfatizan la continuidad ambiental aparente que estimula la minería; sin embargo, esta lectura subvalora otras dinámicas que ocurren en la zona. Con base en observaciones directas de trabajo en campo, para realizar análisis de coberturas vegetales, entrevistas con los habitantes de la zona, revisión de cartografía e investigación de archivo, el presente trabajo muestra procesos como la explotación de recursos vegetales y el pastoreo, como actividades económicas paralelas a las labores mineras, y que no habían sido tratados hasta ahora.

  8. Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: a telescoped low-pressure, low-temperature metamorphic facies series

    Energy Technology Data Exchange (ETDEWEB)

    Schiffman, P.; Elders, W.A.; Williams, A.E.; McDowell, S.D.; Bird, D.K.

    1984-01-01

    In the Cerro Prieto geothermal field, carbonate-cemented, quartzofeldspathic sediments of the Colorado River delta are being actively metasomatized into calc-silicate metamorphic rocks by reaction with alkali chloride brines between 200 and 370 C, at low fluid and lithostatic pressures and low oxygen fugacities. Their petrologic investigations of drill cores and cuttings from more than 50 wells in this field identified a prograde series of zones that include as index minerals wairakite, epidote, prehnite, and clinopyroxene. Associated divariant mineral assemblages are indicate of a very low pressure, low-temperature metamorphic facies series spanning the clay-carbonate, zeolite, greenschist, and amphibolite facies. This hydrothermal facies series, which is now recognized in other active geothermal systems, is characterized by temperature-telescoped dehydration and decarbonation. Its equivalent can now be sought in fossil hydrothermal systems.

  9. Zonificación ecológica del cerro "El Potosí", Galeana, Nuevo León, México

    Directory of Open Access Journals (Sweden)

    Mario A. García A.

    1999-01-01

    Full Text Available Como parte de la propuesta para definir al cerro "El Potosi" como Reserva Especial de la Biosfera, se elaboró un mapa de zonificacion que considera las zonas núcleo, de amortiguamiento y de recuperacion de habitat. Los criterios para la zonificación se consideraron la distribución de la vegetación y las poblaciones de fauna silvestre, derivada de la interpretacion cartográfica elaborada ad hoc, utilizand una imagen de stélite, además de la información sobre la biodiversidad. Se definiereon para la región diez tipos de vegetación y cuatro tipos de uso del suelo, en donde se distribuyen 45 especies bajo estatus de conservación: 19 de plantas y 26 de animales

  10. Approaching viscosity control: electrical heating of extra heavy oil as alternative to diluent injection in down hole in Cerro Negro Field, Faja Petrolifera del Orinoco

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, Manuel [Petroleos de Venezuela SA, PDVSA (Venezuela)

    2011-07-01

    Electrical heating is a method used to enhance oil recovery in extra heavy oil reservoirs. This method can be used when diluent injection or other methods are not able to reduce oil viscosity sufficiently or when problems of product quality or quantity arise. The aim of this paper is to evaluate the performance of electrical heating, individually and simultaneously with injection of diluents. For this purpose, simulations were undertaken in one well with integrated electrical heating and diluent injection in Cerro Negro Field in the Orinoco oil belt, Venezuela. Results have shown that the application of both methods together is more profitable than the application of electrical heating alone. This paper demonstrated that the use of electrical heating and diluent injection combined is a valid alternative to diluent injection alone, reducing production loss.

  11. El Cerro de los Santos: paisaje, negociación social y ritualidad entre el mundo ibérico y el hispano

    Directory of Open Access Journals (Sweden)

    García Cardiel, Jorge

    2015-12-01

    Full Text Available The Iberian shrine of Cerro de los Santos is located next to one of the main roads in the Southeast of the Meseta, in the middle of an area without any town of some entity. This paper aims to highlight its status as a shrine of passage, i.e. as a sacred, safe point where voyagers could rest overnight under the protection of the god. The creation of a statio by the Romans in such a place and its dedication to the goddess Pales provide more circumstantial evidence for this theory. Furthermore, some domestic material contexts can be defined, probably connected with this activity, and clearly different from the well-known ritual contexts of the shrine.La ubicación del santuario ibérico del Cerro de los Santos junto a una de las principales vías de comunicación del sureste meseteño y en el centro de una comarca desprovista de núcleos urbanos de cierta entidad permite subrayar en este artículo su uso continuado como santuario de paso, lugar sacro y seguro al que los caminantes podrían acogerse para pernoctar bajo la protección de la divinidad. La creación de una statio en el enclave en época romana y su dedicación a la diosa Pales no son sino argumentos ulteriores en este sentido. Se identifican además contextos materiales domésticos, distintos de los espacios de culto bien conocidos del santuario, relacionables con esta otra actividad.

  12. Evolución magmática del Granito Peñón Rosado, Cerro Asperecito, flanco occidental de la sierra de Famatina

    Directory of Open Access Journals (Sweden)

    J.A. Dahlquist

    2006-03-01

    Full Text Available El granate es un mineral accesorio poco común en rocas ígneas y constituye un tema relevante de la petrología ígnea. Estudios combinados de petrología, química mineral, geoquímica de roca total y geoquímica isotópica en el cerro Asperecito indican que los granitoides con granate que forman el Granito Peñón Rosado (GPR fueron producidos por la fusión parcial de rocas metasedimentarias con subsecuente diferenciación durante su emplazamiento en el Ordovícico inferior-medio. En este sentido, la facies GPR1 representa un cristalizado temprano, la facies GPR2 representa un fundido diferenciado, y la facies GPR3 un fundido residual. El Granito Peñón Rosado, fue emplazado en condiciones de moderada temperatura (785ºC y presión media (4,4 kb en profundidades de la corteza media (~15 km. El emplazamiento casi sincrónico en la corteza media de una abundante suite metaluminosa durante el Ordovícico inferior-medio (468 Ma en el cerro Asperecito fue suficiente para inducir anatexis local de los metasedimentos circundantes. Los contenidos de elementos mayoritarios (CaO, Na2O y elementos traza (Rb, Sr, Ba en el Granito Peñón Rosado sugieren anatexis a partir de un material inmaduro acumulado en un plataforma continental. Así, el Granito Peñón Rosado es un típico granitoide tipo-S con granate y el modelo establecido aquí puede contribuir a un mejor entendimiento acerca de la cristalización del granate en rocas graníticas.

  13. Cambio del uso de la tierra y pérdida de la cobertura boscosa, comunidades agrarias Sechina, La Ensenada y Cerro San Gil, Izabal Guatemala

    Directory of Open Access Journals (Sweden)

    Eddi Alejandro Vanegas Chacón

    2016-07-01

    Full Text Available En Guatemala, pocas temáticas son abordadas con tanta pasión como el acceso a la tierra y sus relaciones de productividad. Ante el juicio histórico y la evidencia de las estadísticas se deslumbra que las políticas agrarias de los últimos cincuenta años, si bien mitigaron la pobreza en el agro rural conllevaron con ellas daños ambientales irreversibles y deudas agrarias millonarias. Se estudió la dinámica del cambio de uso de la tierra y la pérdida de la cobertura boscosa en las comunidades agrarias beneficiadas por la Ley de Transformación Agraria, Sechina, La Ensenada y Cerro San Gil ubicadas en el departamento de Izabal. Se utilizó fotointerpretación y se realizaron estudios semidetallados de la intensidad de la tierra para el periodo 1958 a 2010. Se concluyó que bajo las premisas de “mejora a la tierra” de la Ley de Transformación Agraria ocurrió cambio de uso y cobertura de la tierra, de forestal a agropecuaria, en las comunidades agrarias Sechina 42%, La Ensenada 46,2% y Cerro San Gil 48,6%, donde se promovieron sistemas de aprovechamiento agrícola que conllevaron al sobre-uso de las tierras en 42%, 78% y 30%, respectivamente. Esto sugiere, que la adquisición de la tierra no es el fin, más bien es el medio, para promover desarrollo rural sostenible, a través de acompañamiento técnico agropecuario, monitoreo y evaluación tanto económica como ambiental.

  14. Entre el sueño del proyecto y la lógica del lugar. La arquitectura imposible de los cerros de Valparaíso

    Directory of Open Access Journals (Sweden)

    Pablo M. Millán-Millán

    2016-04-01

    Full Text Available Valparaíso es el resultado de la unión de dos ciudades en una: la ciudad vertical de los cerros y la ciudad horizontal del Plan –parte plana–. Esta doble naturaleza ha ido configurando una dualidad obligada a convivir y a establecer un continuo diálogo, acabando en la mayoría de los casos en conflicto. Si por un lado está la ciudad global y ortogonal como resultado de la ocupación europea, por otro lado estará la ciudad onírica agarrada a los acantilados ajena a cualquier orden preestablecido. Cada una de estas dos ciudades irá materializando su propia arquitectura: una real y estandarizada, propia de cualquier periferia de ciudad, y otra imposible. Será esta segunda la que vaya evolucionando en un intento continuo de adaptación y será el propio lugar el encargado de rechazar cualquier construcción que no le sea propia. Esta dicotomía quedará plasmada en numerosos proyectos que nunca verán la luz. El objetivo del artículo será mostrar, a partir de numerosos proyectos inéditos descubiertos en Valparaíso, cómo la arquitectura pensada para los cerros nunca llegó a construirse y fue dando paso a unas construcciones a medio camino entre lo real y lo imaginario, entre la lógica y el sueño.

  15. Analysis of the automation and control of the well production conditions in the Cerro Prieto geothermal field, Mexico; Analisis de la automatizacion y del control de las condiciones de produccion de los pozos del campo geotermico de Cerro Prieto, BC, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Murillo Zamora, Isaac [Comision Federal de Electricidad, Mexicali, BC, (Mexico); Ocampo Diaz, Juan de Dios [Universidad Autonoma de Baja California, Mexicali, BC, (Mexico); De la Pena Reyna, Gilberto [Comision Federal de Electricidad, Morelia, Michoacan (Mexico)

    2005-12-01

    Through 31 years of development of the Cerro Prieto geothermal field, the number of wells in operation and the distances between them has been increasing. Now there are 150 wells producing a mixture of water and steam at different ratios, depending on the reservoir characteristics (pressure, temperature, depth, etc.) and the operation conditions in the superficial installations (obstructions in the orifice plates diameter, separator pressures, etc.). Therefore, Comision Federal de Electricidad (CFE) has started a pilot plan to handle the automation and control of the operating conditions of production wells, and to install a data production acquisition system. The initial results of the system are in this paper. [Spanish] A traves de los 31 anos de desarrollo del campo geotermico de Cerro Prieto el numero de pozos en operacion asi como la distancia entre ellos se ha estado incrementando. Ahora hay mas de 150 pozos produciendo una cantidad de mezcla de agua y vapor a diferentes rangos, dependiendo de las caracteristicas del yacimiento (presion, temperatura, profundidad, etc.) y de las condiciones de operacion de las instalaciones superficiales (diametros de placas de orificio obstruidos, presion de los separadores, etc.). Como resultado la Comision Federal de Electricidad (CFE) ha dado inicio a un plan de pruebas para llevar a cabo la automatizacion y control de las condiciones de operacion de los pozos productores, e instalar un sistema con equipos para recoleccion de datos del campo, cuyos primeros resultados se presentan en este articulo.

  16. Geología de la Formación Cerro Negro (Cretácico en Isla Livingston: aportes a su geocronología y contenido paleontológico

    Directory of Open Access Journals (Sweden)

    C.A. Parica

    2007-12-01

    Full Text Available La península Byers se encuentra en el extremo occidental de la isla Livingston, archipiélago de las islas Shetland del Sur. Geológicamente está caracterizada por depósitos marinos, continentales y volcanismo cretácico-terciario que son incluidos en la Formación Cerro Negro de la sección superior del Grupo Byers. Las secuencias magmáticas han sido divididas en dos grupos principales, el primero comprende a las rocas piroclásticas y reúne cinco unidades con un importante desarrollo y distribución en el área. Por su parte, el segundo grupo comprende lavas e intrusivos aflorantes en cerros Don Carlos, Usnea (Usnea Plug, Chester (Chester Cone, Sealer (Sealer Hill y Negro (Negro Hill. Los términos sedimentarios incluyen conglomerados, areniscas y pelitas, de color gris verdoso con estratificación entrecruzada (tanto tabular como en artesa, raramente estratos macizos, laminación horizontal (en algunos casos de naturaleza rítmica, y estructuras de deformación sinsedimentaria (principalmente laminación convoluta. Se propone un ambiente fluvial de depositación, con canales dominados por carga de lecho y barras areno-gravosas bien desarrolladas. En lo que corresponde al sector de planicie de inundación, predominó allí la depositación de material limo-arcilloso por corrientes tractivas débiles durante las crecientes. En las áreas deprimidas de las planicies habría tenido lugar la formación de cuerpos de aguas de poca profundidad en los que se vió favorecida la preservación de la macro y microflora. En las nuevas localidades fosilíferas de península Byers, Domo Rotch (Rotch Dome, cerro Don Carlos, Lomada de las Plantas y 904, ha sido reconocida la presencia de las especies: Araucarites sp., Archangelskya furcata Herbst, Cladophlebis sp., Dictyozamites sp., Elatocladus sp, Phyllopteroides sp., Pseudoctenis sp., Ptyllophyllum menendezii Cantrill, Sphenopteris sp., Eocyathea remesaliae Césari, Sergioa austrina Césari y

  17. Origin and evolution of mineralizing fluids and exploration of the Cerro Quema Au-Cu deposit (Azuero Peninsula, Panama) from a fluid inclusion and stable isotope perspective

    Science.gov (United States)

    Corral, Isaac; Cardellach, Esteve; Corbella, Merce; Canals, Angels; Griera, Albert; Gomez-Gras, David; Johnson, Craig A.

    2017-01-01

    Cerro Quema is a high sulfidation epithermal Au-Cu deposit with a measured, indicated and inferred resource of 35.98 Mt. @ 0.77 g/t Au containing 893,600 oz. Au (including 183,930 oz. Au equiv. of Cu ore). It is characterized by a large hydrothermal alteration zone which is interpreted to represent the lithocap of a porphyry system. The innermost zone of the lithocap is constituted by vuggy quartz with advanced argillic alteration locally developed on its margin, enclosed by a well-developed zone of argillic alteration, grading to an external halo of propylitic alteration. The mineralization occurs in the form of disseminations and microveinlets of pyrite, chalcopyrite, enargite, tennantite, and trace sphalerite, crosscut by quartz, barite, pyrite, chalcopyrite, sphalerite and galena veins.Microthermometric analyses of two phase (L + V) secondary fluid inclusions in igneous quartz phenocrysts in vuggy quartz and advanced argillically altered samples indicate low temperature (140–216 °C) and low salinity (0.5–4.8 wt% NaCl eq.) fluids, with hotter and more saline fluids identified in the east half of the deposit (Cerro Quema area).Stable isotope analyses (S, O, H) were performed on mineralization and alteration minerals, including pyrite, chalcopyrite, enargite, alunite, barite, kaolinite, dickite and vuggy quartz. The range of δ34S of sulfides is from − 4.8 to − 12.7‰, whereas δ34S of sulfates range from 14.1 to 17.4‰. The estimated δ34SΣS of the hydrothermal fluid is − 0.5‰. Within the advanced argillic altered zone the δ34S values of sulfides and sulfates are interpreted to reflect isotopic equilibrium at temperatures of ~ 240 °C. The δ18O values of vuggy quartz range from 9.0 to 17.5‰, and the δ18O values estimated for the vuggy quartz-forming fluid range from − 2.3 to 3.0‰, indicating that it precipitated from mixing of magmatic fluids with surficial fluids. The δ18O of kaolinite ranges from 12.7 to 18.1‰ and

  18. Petrological evolution of subducted rodingite from seafloor metamorphism to dehydration of enclosing antigorite-serpentinite (Cerro del Almirez massif, southern Spain)

    Science.gov (United States)

    Laborda-López, Casto; López Sánchez-Vizcaíno, Vicente; Marchesi, Claudio; Gómez-Pugnaire, María Teresa; Garrido, Carlos J.; Jabaloy-Sánchez, Antonio; Padrón-Navarta, José Alberto

    2016-04-01

    Rodingites are common rocks associated with serpentinites in exhumed terrains that experienced subduction and high pressure metamorphism. However, the response of these rocks to devolatilization and redox reactions in subduction settings is not well constrained. In the Cerro del Almirez ultramafic massif (southern Spain) rodingites constitute about 1-2% of the total volume of exposed rocks. Metarodingites are enclosed in antigorite-serpentinite and chlorite-harzburgite separated by a transitional zone that represents the front of prograde serpentinite-dehydration in a paleo-subduction setting (Padrón-Navarta et al., 2011). Metarodingites occur as boudin lenses, 1 to 20 m in length and 30 cm to 2 m in thickness. During serpentinization of peridotite host rocks, dolerites and basalts precursor of rodingites underwent intense seafloor metasomatism, causing the enrichment in Ca and remobilization of Na and K. Subsequent metamorphism during subduction transformed the original igneous and seafloor metamorphic mineralogy into an assemblage of garnet (Ti-rich hydrogrossular), diopside, chlorite, and epidote. During prograde metamorphism, garnet composition changed towards higher andradite contents. High-pressure transformation of enclosing antigorite-serpentinite to chlorite-harzburgite released fluids which induced breakdown of garnet to epidote in metarodingites. Ti liberation by this latter reaction produced abundant titanite. Released fluids also triggered the formation of amphibole by alkalis addition. Highly recrystallized metarodingites in chlorite-harzburgite present a new generation of idiomorphic garnet with composition equal to 10-30% pyrope, 30-40% grossular and 35-55% almandine + spessartine. This garnet has titanite inclusions in the core and rutile inclusions in the rim. The contact between metarodingites and ultramafic rocks consists of a metasomatic zone (blackwall) with variable thickness (7 to 40 cm) constituted by chlorite, diopside, and titanite

  19. Estudio metalográfico de la calidad del cobre producido en las fundiciones de Cerro Muriano (Córdoba durante el Período Romano Altoimperial

    Directory of Open Access Journals (Sweden)

    Calabrés, R.

    1995-10-01

    Full Text Available The copper obtaining process depends on a great quantity of variables and presents complex controlling. The mentioned obtaining process was well known since the Roman Age. The knowledge of copper of the casting process was higher than expected, taking account of the studies with first melting copper samples localized at an archaeological deposit in Cerro Muriano (Córdoba, Spain and dated at the 1st Century B.C. and 1st Century A.C. The existence of a cellular and dendritic-cellular solidification in the studied samples, together with other realized analysis, show a production of copper with high purity. Present work allows to conclude that the three basic processes on copper casting (roasting, smelting, slagging and conversion were well known. This knowledge was due to the experience, although they did not know the chemical and physical phenomena.

    El proceso de obtención de un cobre, más o menos puro, depende de gran cantidad de variables y es difícil de controlar. Antes de la romanización, dicho proceso de obtención ya era conocido. Utilizando cobres de primera fusión localizados en un yacimiento arqueológico sito en Cerro Muriano (Córdoba datados en los siglos I a.C. y I d.C., se ha determinado que sus elaboradores tenían un conocimiento del proceso de fundición de cobre superior al esperado. La existencia de una solidificación celular y celular dendrítica en las muestras estudiadas, así como los análisis realizados, indican una producción de cobre de alta pureza. El estudio permite concluir que, en época romana, ya se conocían los tres procesos básicos de la obtención de cobre: tostación, fusión y escorificación y conversión. Dicho proceso era conocido gracias a la gran experiencia acumulada, aunque estos metalurgistas desconocían las causas que originaban los resultados finales obtenidos.

  20. Las mineralizaciones de barita de Cerro del Hierro (Sevilla. Características mineralógicas y geoquímica

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    Galán Huertos, E.

    1992-08-01

    Full Text Available Different barite deposits (stratabound, vein and karstic types are occurring in the Lower Cambrian carbonatic materials of the Cerro del Hierro, Sevilla (Ossa-Morena Zone. Calcite, hematite, goethite and minor chalcopyrite are common associated minerals, with limonite and malachite as alterations. The content of barite can be as high as 98 %. There is a close relationship between barite type and Sr content (vein 34S ranges between 32,7 ‰ (stratiform barites and 20,7 ‰ (epigenetic barites. The 87Sr/86Sr ratio for the epigenetic barites oscillates between 0.70873 and 0.71112 which could be the result of the infiuence of different mineralization solutions. A primary origin for the stratabound barites is proposed, in relation with the diagenesis of the limestones occurred during the Lower Cambrian. Epigenetic barites were formed after the Hercynian Orogenesis by remobilization of the stratiform ores, with Ba and Sr supplied from the lixiviation of the host rocks. The last process could be much more important for the karstic barite formation.En los materiales carbonatados del Cámbrico inferior del Cerro del Hierro (Zona de Ossa-Morena existen diversos tipos de mineralizaciones de barita (estratoligadas, filonianas y kársticas. La barita está acompañada de calcita, hematites, goethita, y calcopirita accesoria, y limonitas y malaquita como fases tardías de alteración, y presenta una gran pureza química [ > 98% SO4(Ba,Sr]. Existe una relación entre la tipología de la barita y el contenido en Sr, en el sentido de filonianas 34S en las baritas oscila entre 32,7 ‰ para las estratoligadas y 20,7 ‰ para las epigenéticas. Las razones 87Sr/86Sr determinadas sobre baritas epigenéticas varían entre 0.70873 y 0.71112, lo que puede interpretarse como consecuencia de la participación de diversos tipos de soluciones mineralizantes. Se propone un origen primario de las baritas estratoligadas, en relación con la diagénesis de los

  1. Estudio de los fundentes utilizados en la metalurgia del cobre en Cerro Muriano (Córdoba durante el período Romano Altoimperial

    Directory of Open Access Journals (Sweden)

    Criado, A. J.

    1996-10-01

    Full Text Available There are no doubts that Hispania was, under the Roman Empire, the most profitable and abundant in resources of all the mining districts exploded by Rome -Hispania, Galia, Danubian Provinces, Dacia, Greece, Asia Minor, Syria, Egypt and North Africa-. Plinius gives the same data and hands many more in the passages dedicated to the mining and the working of the metals in his Natural History. Of all the many mining places that this author refers, the exploiting in copper at Cerro Muriano presents the main interest; of this he says that it was of an unbeatable quality, used, among other applications, to manufacture the very famous "Copper of Campania". The utilization of fusing agents, adapted to the process of copper obtainment, is fundamental for obtaining this high quality. The addition of these fusing agents was very important for the control of the work parameters and to reach the required temperatures. The high purity of the obtained copper shows a very close knowledge of the phenomena involved in the process.

    Durante el Imperio Romano, de todos los distritos mineros explotados por Roma -Hispania, Galia, las provincias danubianas, Dacia, Grecia, Asia Menor, Siria, Egipto y el Norte de África-, sin duda el más rentable y más abundante en recursos era Hispania. Plinio facilita muchos datos en los pasajes dedicados a la minería y el trabajo de los metales en su Historia Natural. Entre los muchos lugares mineros que este autor cita, nos interesa ahora la explotación de cobre en Cerro Muriano, del cual dice que era de una calidad inmejorable, utilizado, entre otras aplicaciones, para fabricar el famosísimo cobre de Campania. Para poder obtener esta elevada calidad, es fundamental la utilización de fundentes adecuados en el proceso de obtención de cobre. La adición de estos fundentes era vital para controlar los parámetros de trabajo y alcanzar las temperaturas requeridas. La elevada pureza del cobre obtenido demuestra un

  2. A Conceptual Model to Link Anomalously High Temperature Gradients in the Cerros del Rio Volcanic Field to Regional Flow in the Espanola Basin, New Mexico

    Science.gov (United States)

    Fillingham, E. J.; Keller, S. N.; McCullough, K. R.; Watters, J.; Weitering, B.; Wilce, A. M.; Folsom, M.; Kelley, S.; Pellerin, L.

    2015-12-01

    Temperature-depth well data along with electromagnetic (EM) data were collected by students of the Summer of Applied Geophysics Experience (SAGE) 2015 field season in the Espanola Basin, New Mexico. The data from this year, in addition to data acquired since 2013, were used to construct a conceptual east-west cross-section of the Espanola Basin and the adjacent highlands in order to evaluate the regional flow system. Vertical geothermal gradients from several monitoring wells were measured using a thermistor. Anomalously warm geothermal gradients were mapped in the Cerros del Rio volcanic field in the basin just east of the Rio Grande. Temperature gradients are up to 70℃/km, while the background geothermal gradients in the Rio Grande rift zone generally show 28℃-35℃/km. This anomaly extends to the Buckman well field, which supplies water to the city of Santa Fe. Overpumping of this well field has led to subsidence in the past. However, discharge temperature plots indicate that the temperature gradients of the Buckman field may be rebounding as pumping is reduced. Audiomagnetotelluric (AMT) and transient electromagnetic (TEM) data were acquired in the vicinity of three monitoring wells. TEM and AMT methods complement each other with the former having depths of investigation of less than ten to hundreds of meters and AMT having depths of investigation comparable to the wells deeper than 500m. These datasets were used collectively to image the subsurface stratigraphy and, more specifically, the hydrogeology related to shallow aquifers. The EM data collected at these wells showed a trend indicating a shallow aquifer with a shallower resistive layer of approximately 100 ohm-m at 70-100 meters depth. Beneath this resistive layer we resolved a more conductive, clay-rich layer of 10 ohm-m. These resistivity profiles compliment the electrical logs provided by Jet West, which indicate shallower sandstone interbedded with silt on top of more silt-dominant layers. Our

  3. Mecanismo de inserción del Laboratorio Tecnológico del Uruguay en el Parque Tecnológico Industrial del Cerro

    Directory of Open Access Journals (Sweden)

    Laura Márquez

    2011-05-01

    Full Text Available El Laboratorio Tecnológico del Uruguay, LATU, teniendo en cuenta su misión: "Impulsar el desarrollo sustentable del país y su inserción internacional a través de la innovación y transferencia de soluciones de valor, en servicios analíticos, metrológicos, tecnológicos, de gestión y evaluación de la conformidad de a cuerdo a la normativa aplicable", está trabajando en el apoyo a las micro, pequeñas y medianas empresas del país. Como estrategia para contribuir al logro de la misión, se ha iniciado una política de descentralización, eligiendo zonas de actividad con requerimientos similares, en cuanto a las necesidades de mejora de la competitividad de las empresas. En la zona de Montevideo llamada el Cerro, el gobierno municipal gestiona un Parque Tecnológico Industrial, PTIC, apoyando y alojando en su predio, 58 empresas. Este Parque se puede ver como un conglomerado de empresas, en una misma zona, con necesidades similares. El mecanismo de inserción del LATU en el PTIC, ha contado con una herramienta fundamental que es la instalación de una oficina en el propio Parque, cuyo objetivo principal es facilitar y asegurar la contribución del LATU al desarrollo y competitividad de las mipymes allí agrupadas.AbstractAttending to the Technological Laboratory of Uruguay (LATU's mission, to promote the sustainable development of the country and its international insertion through innovation and transfer of valuable solutions, it is working on support for micro, small and medium companies. As a management strategy to achieve the mission, a policy of decentralization, approaching to the enterprises, it's being implemented. In this context, it has been developed a methodology for insertion in the Industrial Technological Park of Cerro, PTIC. This park, which is managed by the municipal government, agglomerates a group of companies, in the same area with similar needs. The LATU's mechanism of insertion in the PTIC, has counted on with a

  4. Andesita Cerro Bola: Nueva unidad vinculada al magmatismo mioceno de la Cordillera de Olivares, San Juan, Argentina (30°35´S; 69°30´O Cerro Bola Andesite: New unit linked to the Miocene magmatism of the Olivares Cordillera, San Juan (30°35' S ; 68°30' W

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    A.F. Wetten

    2005-03-01

    Full Text Available El área de estudio se halla en la zona de Tocota, inmediatamente al este de la Cordillera de Olivares, en el borde oriental de la Cordillera Frontal, provincia de San Juan. En ella se encuentran unidades ígneas y sedimentarias del ciclo gondwánico, las que fueron intruidas y cubiertas en relación discordante por cuerpos subvolcánicos y volcánicos asignados anteriormente al ciclo ándico en sentido amplio, los cuales constituyen el principal objeto del presente estudio. Estos cuerpos han sido mapeados a fin de poder caracterizarlos adecuadamente, en el contexto estratigráfico de la región. Los afloramientos de interés han sido reconocidos en el cerro Bola y alrededores, donde se observan distribuidos irregularmente, cubriendo un área superior a 5 km². Las rocas, de coloración gris clara y composición andesítica - fenoandesítica, presentan estructuras de domo y colada. Estos afloramientos serían correlacionables con la unidad volcánica Pircas (Mioceno, la que aflora al oeste, y conformarían un evento magmático posterior al de pórfidos de diferente composición situados tanto en el arroyo Chita como en el cerro Divisadero. La extensión del área involucrada, la uniformidad litológica, el bajo grado de alteración y una edad radimétrica obtenida por el método K/Ar, fueron considerados para proponer a estas volcanitas como una unidad litoestratigráfica de edad miocena superior, con la denominación de Andesita Cerro Bola.The study area is located in the region of Tocota Creek, close to the Cordillera Olivares, eastern border of the Frontal Range, San Juan province. In this place, igneous and sedimentary units belonging to the Gondwanic cycle, were recognized. These units were intruded and unconformably covered by subvolcanic and volcanic bodies, which were commonly referred to the Tertiary or Andean cycle. The study of these bodies is the main proposal of this work. These bodies had been mapped in order to characterize them

  5. Edad y rasgos petrográficos y geoquímicos de cuerpos subvolcánicos asignables a la Formación Cerro León, este del Macizo del Deseado, Santa Cruz Age and petrography and geochemistry features of subvolcanic outcrops from Cerro León Formation, east of the Deseado Massif, Santa Cruz

    Directory of Open Access Journals (Sweden)

    D. Guido

    2004-12-01

    Full Text Available Se presentan nuevos afloramientos de cuerpos subvolcánicos correlacionables con la Formación Cerro León en el sector oriental del Macizo del Deseado. Esta unidad aflora en dos sectores, en el bajo Leonardo y en el afloramiento Bahía Laura del Complejo Río Deseado. El primer sector presenta trece diques y un filón capa intruyendo a las sedimentitas pérmicas de la Formación La Golondrina y el segundo sector comprende tres diques que intruyen a rocas del basamento. Se trata de rocas de color gris a negro, frecuentemente alteradas, con textura microgranuda a porfírica, con fenocristales de plagioclasa, diópsido (En42 Fs11 Wo47 y en menor medida de hornblendas ricas en Mg (magnesio hastingsita, en una matriz holocristalina de textura intergranular. Son rocas subalcalinas de composiciones basalto-andesita y con afinidades calcoalcalinas. La edad Ar/Ar obtenida en una de estas muestras (180,1±1,5 Ma representa la primer determinación realizada en esta unidad y es coherente con las relaciones estratigráficas observadas para esta formación. La comparación con rocas ígneas jurásicas de la provincia geológica Macizo del Deseado, favorece la vinculación temporal y genética con el evento volcánico-piroclástico del Jurásico medio a superior (Formación Bajo Pobre y Grupo Bahía Laura. Sin embargo, la diferencia en las edades Ar/Ar, sugieren una interrupción entre el evento subvolcánico (180 Ma y el volcanismo Jurásico medio a superior (177 a 150 Ma. Se considera, preliminarmente, que los cuerpos subvolcánicos de la Formación Cerro León representarían las primeras evidencias magmáticas del rift jurásico en el Macizo del Deseado.New subvolcanic outcrops, correlated with the Cerro León Formation and located in the eastern Deseado Massif, are presented. This unit outcrops in two sectors, the Leonardo depression and the Bahía Laura outcrop of the Río Deseado Complex. In the first sector there are thirteen dikes and a sill

  6. Evolución petrotectónica del distrito minero Cerro Áspero y modelo de emplazamiento de los depósitos wolframíferos, Córdoba Petrotectonic evolution of the Cerro Aspero mining district and emplacement model of the wolframiferous deposits, Córdoba

    Directory of Open Access Journals (Sweden)

    D. Mutti

    2005-03-01

    Full Text Available La geología relacionada con la intrusión granítica Cerro Áspero expone en el faldeo oriental de la sierra de Comechingones, mineralización metalífera diseminada y en brechas hidráulicas, conectada genéticamente a un grupo minero integrado por un sistema de enjambres de venas, vetas y mantos cuarzosos con direcciones NNO, ONO y N. La comarca presenta polimetamorfismo y al menos, dos eventos de cizallamiento simple (D3 y D4 y estructuras penetrativas (S2, S3 y S4 que se desarrollaron desde el Pampeano hasta el Famatiniano inclusive, favoreciendo la intrusión anorogénica del batolito Cerro Áspero a partir del Devónico tardío. Como consecuencia del evento magmático fueron reactivadas las estructuras, movilizando fluidos hidrotermales por las anisotropías del terreno y debajo de un nivel de anfibolitas macizo que actuó como una barrera impermeable. La acción de un esfuerzo máximo s1 (330º contribuyó al desarrollo del sistema mineralizado siguiendo el patrón de fracturamiento del modelo de Riedel y propició la construcción del lineamiento mineral principal en una faja de cizalla simple dextral de posición 285º (S5. El fluido magmático - hidrotermal evolucionó mediante numerosos pulsos de ruptura y apertura de las inhomogeneidades rocosas, con sellado de cavidades por mecanismos de cierre con fracturamiento y relleno y disolución por presión. Estos mecanismos precipitaron sílice con hábito fibroso y reconcentraron elementos metálicos bajo un régimen de tracción y presión de fluido de poro estimada en 195 MPa. La edad de la mineralización de uno de sus estadios fue determinada en 343,8 ± 10,8 Ma, mediante una datación K/Ar en muscovita.Metalliferous mineralization, disseminated and in hydraulic breccias, in connection with a mining group composed of three swarm systems of quartz veinlets, veins and sills striking NNW, WNW and N, is exposed in the geological setting related to the Cerro Aspero granitic intrusion

  7. El volcanismo bimodal del volcán cerro Corona, Alta Sierra de Somún Curá, provincia de Río Negro Bimodal volcanism of the Cerro Corona volcano in the Alta Sierra de Somún Curá (Río Negro province

    Directory of Open Access Journals (Sweden)

    Guadalupe Maro

    2012-03-01

    Full Text Available La Alta Sierra de Somún Curá es uno de los complejos volcánicos terciarios postplateau en el ambiente de la meseta basáltica de Somún Curá, en la Patagonia extrandina. En ella se encuentra el cerro Corona, un volcán en escudo que corresponde al centro de mayor altura en la región. Está construido por rocas efusivas y piroclásticas subordinadas, fundamentalmente traquiandesíticas-basálticas, con variaciones traquíticas tanto en sus flancos como en su cráter. A pesar de la bimodalidad compositional con una importante discontinuidad entre el 54 y 58 % en peso de SiO2, el presente trabajo propone que las traquitas son el producto de la evolución por cristalización fraccionada de las traquiandesitas basálticas, con cierta influencia de recargas máficas a la cámara magmática de acuerdo a la presencia de texturas de desequilibrio en los fenocristales, principalmente de las rocas félsicas.The Cerro Corona is a shield volcano situated in the Alta Sierra de Somún Curá, one of the tertiary volcanic complex that constitute the Meseta de Somún Curá, in the Extrandean Patagonia. It is the highest center in the region and it is compound mainly of basaltic trachyandesites, with trachytic variations on its flanks and crater. Despite the compositional bimodality with an important compositional gap between 54% and 58% in weight in SiO2, this work suggests that trachytes are the product of the evolution of basaltic trachyandesites through fractional crystallization, with some influence of mafic recharge to the magmatic chamber, in agreement with the presence of disequilibrium textures in fenocrystals, essentially in felsic rocks.

  8. ANÁLISIS DE MACRORRESTOS VEGETALES EN EL SITIO ARQUEOLÓGICO LOS TRES CERROS 1 (ISLA LAS MORAS, VICTORIA, ENTRE RÍOS / Macroremains plant analysis on the Tres Cerros 1 archaeological site (Las Moras island, Victoria, Entre Ríos.

    Directory of Open Access Journals (Sweden)

    María de los Milagros Colobig

    2015-06-01

    Full Text Available El presente trabajo es la primera aproximación al estudio de macrorrestos botánicos en el sitio Los Tres Cerros 1 (isla Las Moras, Victoria, Entre Ríos. Estos restos fueron recuperados mediante la técnica de flotación manual. A partir del material extraído, se exploró el rol de los recursos vegetales y su importancia en la subsistencia en los grupos humanos que habitaron el Delta Superior del río Paraná durante el Holoceno tardío. Se identificaron cinco familias: Solanaceae, Chenopodiaceae, Polygonaceae, Poaceae (Maideae y Oryzoideae y Amaranthaceae. Los estudios permitieron estimar que a partir de 700 ARCP hubo un incremento en la abundancia y variabilidad de recursos vegetales utilizados con respecto a períodos anteriores. La presencia de elementos oryzoides, y graminoides (específicamente Maideae evidenció la existencia de vegetales silvestres y domesticados, aportando nuevos registros sobre el aprovechamiento, manejo y cultivo de las plantas en el área de estudio en el Holoceno tardío.   Abstract  This paper entails the first approach to macrobotanical remains obtained from Los Tres Cerros 1 (Isla Las Moras, Victoria, Entre Ríos. The remains were recovered by means of manual flotation technique. The extracted material allowed us to explore the role played by vegetable resources role and their importance to the subsistence of human populations of Upper Paraná Delta during the late Holocene. Five botanical families were recognized: Solanaceae, Chenopodiaceae, Polygonaceae, Poaceae (Maideae and Ehrhartoideae and Amaranthaceae. Studies estimate that from 700 RCYBP, there was an increase in the abundance and variability of plant resources used, as compared to previous periods. The presence of oryzoides and graminoid elements (specifically Maideae showed the presence of wild and domesticated plants, providing new records on the use of plants in the area studied, in the late Holocene.

  9. SIMULACIÓN DE FLUJOS PIROCLÁSTICOS DEL VOLCÁN CERRO MACHÍN, COLOMBIA, MEDIANTE LA APLICACIÓN DE HERRAMIENTAS DE ARCGIS©

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    Elsa Adriana Cárdenas Quiroga

    2012-01-01

    Full Text Available Cerro Machín es un volcán activo, caracterizado en el pasado por erupciones explosivas de tipo pliniano y ubicado en un sector de gran importancia económica. Desde la década de los noventa se han desarrollado varios modelos de simulación para determinar el área que podría resultar afectada en una nueva erupción, pero estos modelos se basan en programas con variables predeterminadas que no son fácilmente modificables. Por tanto, se diseñó una aplicación del modelo de simulación Model Builder de las herramientas del software ArcGIS© para facilitar el proceso de análisis de los flujos piroclásticos expulsados por ese volcán en tres eventos eruptivos identificados y modelados previamente, con el objetivo de crear una aplicación fácilmente adaptable a cambios en las variables de simulación y que pudiera ser empleada también para modelar otros volcanes. Los resultados obtenidos resultan compatibles y similares a los obtenidos en simulaciones previas, lo que indica que la aplicación desarrollada es funcional.

  10. El volcanismo bimodal del volcán cerro Corona, Alta Sierra de Somún Curá, provincia de Río Negro

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    Guadalupe Maro

    2012-03-01

    Full Text Available La Alta Sierra de Somún Curá es uno de los complejos volcánicos terciarios postplateau en el ambiente de la meseta basáltica de Somún Curá, en la Patagonia extrandina. En ella se encuentra el cerro Corona, un volcán en escudo que corresponde al centro de mayor altura en la región. Está construido por rocas efusivas y piroclásticas subordinadas, fundamentalmente traquiandesíticas-basálticas, con variaciones traquíticas tanto en sus flancos como en su cráter. A pesar de la bimodalidad compositional con una importante discontinuidad entre el 54 y 58 % en peso de SiO2, el presente trabajo propone que las traquitas son el producto de la evolución por cristalización fraccionada de las traquiandesitas basálticas, con cierta influencia de recargas máficas a la cámara magmática de acuerdo a la presencia de texturas de desequilibrio en los fenocristales, principalmente de las rocas félsicas.

  11. Implications for organic maturation studies of evidence of a geologically rapid increase and stabilization of vitrinite reflectance at peak temperature: Cerro Prieto geothermal system, Mexico

    Science.gov (United States)

    Barker, C.E.

    1991-01-01

    A short-term rapid heating and cooling of the rock in well M-94 below 1300 m was caused by a pulse of hot water passing through the edge of the Cerro Prieto, Mexico, geothermal system. Below 1300 m, the peak paleotemperatures were about 225-250??C, but equilibrium well log temperatures indicate a decrease to 150-210??C at present. This hot water pulse sharply increased vitrinite reflectance to levels comparable to those measured in the central part of the system, even though studies of apatite fission-track annealing indicate that the duration of heating was only 100-101 yr in M-94, in contrast to 103-104 yr in the central part of the system. The quick change of the vitrinite reflectance geothermometer indicates that thermal maturation reactions can stabilize, after a geologically short period of heating, to a level consistent with peak temperature under moderate to high-temperature diagenesis in open, fluid-rich, geothermal systems. -from Author

  12. NUEVOS APORTES AL CONOCIMIENTO DE LA HERPETOFAUNA DE LA FORMACIÓN CERRO AZUL (MIOCENO SUPERIOR, PROVINCIA DE LA PAMPA, ARGENTINA

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    AGUSTÍN SCANFERLA

    2015-01-01

    Full Text Available RESUMENSe describen nuevos materiales fósiles de anfibios y reptiles hallados en sedimentos referidos a la Formación Cerro Azul (Mioceno Superior, procedentes de numerosas localidades de la provincia de La Pampa, Argentina. Los nuevos registros se basan en un resto craneano de anuro asignado al géneroCeratophrys, restos de caparazón de tortugas terrestres del géneroChelonoidis, vértebras asignables al lagarto de la familia TeiidaeTupinambis, y una vértebra troncal de serpiente comparable al género de colubroideos actualesPhilodryas. Tanto los registros terciarios previos de géneros actuales de anfibios y reptiles en América del Sur, como así también la asociación recuperada en el Mioceno Superior de La Pampa sugieren que la mayoría de los géneros que componen la herpetofauna Neotropical estaban presentes en el Mioceno, patrón similar al observado en otras regiones del mundo.

  13. Jurassic tetrapods and flora of Cañadón Asfalto Formation in Cerro Cóndor area, Chubut Province

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    Ignacio H. Escapa

    2008-12-01

    Full Text Available The plant and tetrapod fossil record of the Cañadón Asfalto Formation (Middle to Late Jurassic found in Cerro Cóndor area (Chubut Province is summarized here. The flora is dominated by conifers (Araucariaceae, Cupressaceae sensu lato but also includes ferns and equisetaleans. The tetrapod fauna is composed of dinosaur taxa described in the 70's as well as other remains recently described and other vertebrate groups such as amphibians, turtles, and mammals. The amphibian remains have been interpreted as representatives of a new species of Notobatrachus, considered one of the most basal members of the anuran lineage. Similarly, turtle remains have been recently recognized as a new species of basal turtle, bringing valuable information about the early evolution of this group. The dinosaur remains are largely dominated by saurischian taxa, represented by basal forms of Eusauropoda and Tetanurae. In addition, three different mammalian species have been identified and considered as early representatives of an endemic Gondwanan mammalian fauna. The fossil record of this formation represents the most completely known biota from the continental Middle to Late Jurassic of the Southern Hemisphere and one of the most complete of the entire world.

  14. Observation and modeling of gravity wave propagation through reflection and critical layers above Andes Lidar Observatory at Cerro Pachón, Chile

    Science.gov (United States)

    Cao, Bing; Heale, Christopher J.; Guo, Yafang; Liu, Alan Z.; Snively, Jonathan B.

    2016-11-01

    A complex gravity wave event was observed from 04:30 to 08:10 UTC on 16 January 2015 by a narrow-band sodium lidar and an all-sky airglow imager located at Andes Lidar Observatory (ALO) in Cerro Pachón (30.25°S, 70.73°W), Chile. The gravity wave packet had a period of 18-35 min and a horizontal wavelength of about 40-50 km. Strong enhancements of the vertical wind perturbation, exceeding 10 m s-1, were found at ˜90 km and ˜103 km, consistent with nearly evanescent wave behavior near a reflection layer. A reduction in vertical wavelength was found as the phase speed approached the background wind speed near ˜93 km. A distinct three-layered structure was observed in the lidar data due to refraction of the wave packet. A fully nonlinear model was used to simulate this event, which successfully reproduced the amplitudes and layered structure seen in observations. The model results provide dynamical insight, suggesting that a double reflection occurring at two separate heights caused the large vertical wind amplitudes, while the three-layered structure in the temperature perturbation was a result of relatively stable regions at those altitudes. The event provides a clear perspective on the filtering processes to which short-period, small-scale gravity waves are subject in mesosphere and lower thermosphere.

  15. IMPACTO EN AFLUENTES DEL RÍO PILCOMAYO POR CONTAMINANTES ADICIONALES DE DRENAJE ÁCIDO DE MINAS DESDE CERRO RICO, POTOSÍ-BOLIVIA

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    William H.J. Strosnider

    2014-01-01

    Full Text Available La minería intensiva y el procesamiento del cuerpo mineralizado del Cerro Rico de Potosí (Bolivia ha ocurrido desde 1545. Para avanzar la investigación sobre descargas de drenaje acido de minas (DAM y su conexión a la contaminación río abajo, se generaron datos en dos muestreos durante la temporada más extrema de lluvia y sequía. Las concentraciones en el DAM y arroyos receptores de Ag, B, Ba, Mo, Sb, Se, Sn, y V fueron superiores a los límites de descarga permitidos por la legislación Boliviana y las directrices sobre arroyos receptores del DAM, tal como las normas de agricultura internacionales. Concen traciones elevadas de elementos de tierras raras han sido documentados en esta ubicación. Los resultados del estudio indican que la contaminación por minería impactan significativamente el río estudiado, y pone de manifiesto la importancia de su remediación.

  16. Comparative study of the amplification of ground motion using seismic noise and recent earthquakes adjacent to the Cerro Prieto volcano, Baja California

    Science.gov (United States)

    Vega, F. D.; Vidal-Villegas, A.

    2009-12-01

    We have chosen an area of approximately 79 km2, centered around the Cerro Prieto volcano, in the Mexicalli valley, Baja California, based on elevated registered acceleration data. The GEO station, located in the Cerro Prieto geothermal field has registered seismic accelerations on the order of 492 gales. The local residents near the study area have reported feeling numerous smaller magnitude earthquakes, compared to those of the nearby populated city of Mexicalli. Does there exist an amplified seismic signal in the area? If so, what is the cause of the amplification? The objective of our study is to answer these questions and determine the subsurface (0-50 m) structure in 4 specific sites. To obtain these answers, we registered seismic noise samples using short period seismometers (1 s), intermediate (5 s) and 16 bit recorders, along a linear profile which crosses the volcano with an 18 degree NE orientation. Furthermore, we analyzed ground-motion data (from 2004-2006), obtained from 24-bit accelerographs. Using both types of data (noise and accelegraphs) we calculated the H/V spectral ratios, and the relative ratios between both sites. To determine the subsurface structure, we used a unidimensional model of the H/V ratios, based on the methodology used by Huerta-Lopez et al., 2005. The H/V spectral ratios from the seismic noise adjacent to the volcano display amplitude of 1 in the frequency range (0.8 - 30 Hz). In contrast, the amplitude in the volcano crater (159 m.a.s.l.) was 6 in the frequency range (0.8 - 3 Hz). The average H/V relative ratio of the crater and the adjacent sites is 4, with frequencies between 0.8 and 1.2 Hz. The S-wave H/V ratios for the VCP acceleration station (110 m.a.s.l.), are near 8, with frequencies between 1 and 2. The H/V spectral ratios from the seismic noise for the geothermal field display amplitude of 4 for frequencies between 0.8 and 1.3 Hz, while the results from the S wave display amplitudes of 5 between 1.5 and 3 Hz. In the

  17. Ecological Impacts of the Cerro Grande Fire: Predicting Elk Movement and Distribution Patterns in Response to Vegetative Recovery through Simulation Modeling October 2005

    Energy Technology Data Exchange (ETDEWEB)

    Rupp, Susan P. [Texas Tech Univ., Lubbock, TX (United States)

    2005-10-01

    In May 2000, the Cerro Grande Fire burned approximately 17,200 ha in north-central New Mexico as the result of an escaped prescribed burn initiated by Bandelier National Monument. The interaction of large-scale fires, vegetation, and elk is an important management issue, but few studies have addressed the ecological implications of vegetative succession and landscape heterogeneity on ungulate populations following large-scale disturbance events. Primary objectives of this research were to identify elk movement pathways on local and landscape scales, to determine environmental factors that influence elk movement, and to evaluate movement and distribution patterns in relation to spatial and temporal aspects of the Cerro Grande Fire. Data collection and assimilation reflect the collaborative efforts of National Park Service, U.S. Forest Service, and Department of Energy (Los Alamos National Laboratory) personnel. Geographic positioning system (GPS) collars were used to track 54 elk over a period of 3+ years and locational data were incorporated into a multi-layered geographic information system (GIS) for analysis. Preliminary tests of GPS collar accuracy indicated a strong effect of 2D fixes on position acquisition rates (PARs) depending on time of day and season of year. Slope, aspect, elevation, and land cover type affected dilution of precision (DOP) values for both 2D and 3D fixes, although significant relationships varied from positive to negative making it difficult to delineate the mechanism behind significant responses. Two-dimensional fixes accounted for 34% of all successfully acquired locations and may affect results in which those data were used. Overall position acquisition rate was 93.3% and mean DOP values were consistently in the range of 4.0 to 6.0 leading to the conclusion collar accuracy was acceptable for modeling purposes. SAVANNA, a spatially explicit, process-oriented ecosystem model, was used to simulate successional dynamics. Inputs to the

  18. Models of Metabolic Community Structure in Martian Habitable Environments: Constraints from a Terrestrial Analog Acid-Sulfate Fumarole Environment, Cerro Negro Volcano, Nicaragua

    Science.gov (United States)

    Rogers, K. L.; McCollom, T. M.; Hynek, B. M.

    2014-12-01

    Microbial habitability in extreme environments on Earth is described by microscale geochemical conditions that constrain metabolic niches in concert with long-term habitat stability that is governed by dynamic geologic processes. Using terrestrial analogs to identify habitable martian environments requires correlating microscale geochemical constraints with reconstructions of past martian environments that are based on global-scale observations. While past martian environments can be characterized by primary parameters (e.g. pH, redox, mineralogy, thermal history), microbial habitability on Earth is a complex function of both primary and derived parameters (e.g. metabolic reaction energetics, chemical & thermal gradients, flow dynamics). In recent years we have been investigating acid-sulfate fumaroles at the Mars analog site, Cerro Negro Volcano, Nicaragua, where habitability is constrained by steep thermal gradients, spatially- and temporally-variable vent dynamics, and limited water and nutrient availability. The most common niche identified thus far is found in fumaroles that host mixed photosynthetic and chemosynthetic endolithic microbial communities. One such endolith is dominated by acidic red algae (Cyanidiales), aerobic bacterial heterotrophs (Ktedonobacteria), and archaeal thermoacidophiles (Hyperthermus, Caldisphaera, and Thermofilum). An analysis of the metabolic structure suggests that primary production by the red algae supports the growth of heterotrophic thermoacidophiles. Diversification among the chemoheterotrophs with respect to temperature and oxygen tolerance suggests community adaptation to environmental gradients or variable venting dynamics. Furthermore, individual cells within the endolith are silica-encrusted, providing the possibility for biosignature formation and preservation. Putative hydrothermal environments on early Mars with similar conditions could have supported endolithic communities with comparable metabolic strategies. Even

  19. Prácticas de sacrificio en el Cerro de la Mesa (Alcolea de Tajo, Toledo: el depósito ritual de la Casa 1

    Directory of Open Access Journals (Sweden)

    Ana CABRERA DÍEZ

    2014-06-01

    Full Text Available Los depósitos con restos óseos animales enterrados bajo el pavimento en ámbitos domésticos forman parte de prácticas rituales bien conocidas en la Protohistoria peninsular, tradicionalmente asociadas a la fundación o remodelación de nuevos edificios o a ritos vinculados a la propiciación y la fertilidad. Aunque los ejemplos mejor estudiados se encuentran en la zona levantina, el fenómeno también se conoce en yacimientos del interior. Este artículo tiene por objeto presentar un depósito ritual excavado en el poblado vetón del Cerro de la Mesa, en el valle medio del Tajo, cuyas características formales lo emparentan con las ofrendas domésticas de la zona ibérica. Se trata de un hoyo situado en el umbral de la Casa 1, que contiene los restos seleccionados de varios ovinos y un pequeño cuenco cerámico colocado en posición invertida. El análisis de los restos óseos, el contenido del cuenco y el estudio del contexto arqueológico en que se situaba el depósito han permitido relacionarlo con prácticas de sacrificio y libación dentro del marco de la religiosidad vetona. Este trabajo pretende igualmente contribuir a la formación de un corpus peninsular de inhumaciones rituales de animales en contextos domésticos, que impulse el adecuado estudio de la ritualidad protohistórica.

  20. Evaluación del estado de conservación de las microcuencas pertenecientes a los Cerros Orientales de Chía, Cundinamarca, Colombia

    Directory of Open Access Journals (Sweden)

    Arévalo Santos Carolina

    2006-06-01

    Full Text Available El trabajo se realizó en colaboración con la Alcaldía Municipal de Chía, Cundinamarca, Colombia, con el fin de
    aproximarnos al estado de conservación de las microcuencas localizadas sobre la cota de altitud 2.600-3.200 msnm, en las veredas de Yerbabuena y Fusca, donde se identificaron cuatro microcuencas de interés: Mana- Yerbabuena, Coseteja, Fusca y Honda-Pan de Azúcar. El documento final se presenta como un instrumento para el conocimiento de los cerros Orientales de Chía a una escala municipal, cuyo enfoque establece los diferentes tipos de cobertura de vegetación existentes como indicador del estado actual de las microcuencas y evidencia situaciones críticas que pueden propiciar su total degradación. Los resultados permiten concluir que los procesos de transformación son bastante intensos, debido básicamente a la acción antrópica que ha hecho de los procesos urbanísticos el factor de amenaza más significativo, que ha conducido a la pérdida acelerada de la vegetación, apertura de vías de acceso, uso inadecuado de las fuentes hídricas etc. El producto principal de este  análisis es la generación de un mapa de áreas de interés ambiental que proponemos deben ser proyectadas ya sea
    para fines de conservación, restauración, recuperación y áreas cuyo manejo de conflictos debe ser prioridad. La
    importancia de establecer el estado de conservación deriva de la necesidad de proporcionar bases para el desarrollo de planes de manejo ambiental.

  1. Apresentacão do Projeto de extensão universitaria "Fortalecimento das Capacidades das Educadoras do Programa CAIF no estado de Cerro Largo-Uruguai"

    Directory of Open Access Journals (Sweden)

    Mariana Porta Galván

    2015-12-01

    Full Text Available Dentro de la línea de investigación Estado, políticas sociales y ciudadanía en frontera, es relevante conocer la realidad de las políticas sociales orientadas a la primera infancia y sus implementaciones. Esta ponencia presenta un proyecto de extensión universitaria realizada con los centros CAIF de Cerro Largo con el propósito de fortalecer las prácticas de los operadores sociales de estos centros, a partir de las siguientes preguntas: ¿Qué características asume la implementación de esta política pública en un departamento fronterizo? ¿Qué desafíos plantea a sus operadores? Consideramos que la implementación de una política social, más allá de la forma en que se concibe, diseña y expresa en sus documentos, implica un proceso de apropiación que conlleva interpretaciones y adaptaciones que se manifiestan en prácticas. Estas, a su vez, responden a disposiciones, hábitos y saberes (entendidos como conocimientos tácitos y explícitos de los operadores involucrados, en un vínculo directo con la cultura propia de los contextos en los que se desarrollan. En ese proceso de implementación y sus múltiples niveles de gestión, se encuentran los desafíos a los cuales pretendemos aportar desde una propuesta de capacitación de operadores, que responda a la diversidad de cada territorio y de cada contexto social.

  2. Active hydrothermal metamorphism in the Cerro Prieto geothermal system, Baja California, Mexico: a telescoped low P/T facies series. [Abstract only

    Energy Technology Data Exchange (ETDEWEB)

    Schiffman, P. (Univ. of California, Riverside); Elders, W.A.; Williams, A.E.; McDowell, S.D.; Bird, D.K.

    1983-03-01

    In the Cerro Prieto geothermal system, carbonate-cemented, quartzo-feldspathic sediments of the Colorado River delta are being actively recrystallized into calc-silicate metamorphic rocks through intense fluid/rock interaction with alkali chloride brine (1.5 x 10/sup 4/ ppM TDS) at temperatures between 200/sup 0/ and 370/sup 0/C, fluid pressures <0.25 Kb, lithostatic pressures <1.0 Kb, and oxygen fugacities close to the QFM buffer. Petrologic investigations of cuttings and core from more than 50 wells in this field reveal a prograde series of calc-silicate mineral zones with index metamorphic minerals: wairakite (wr), epidote (ep), prehnite (pr), and calcic clinopyrosene (cpx). The compositions of these and other key phases: wr (Ca/Ca + Na + K + 0.97), ep (Fe/Fe + Al/sup vi/ = 0.11 to 0.31), pr (Fe/Fe + Al/sup vi/ = 0.01 to 0.28), cps (close to Wo/sub 50/ and Mg/Mg + Fe + Mn = 0.23 to 0.90), actinolite (0.20 Al/sup iv//15 cations and Mg/Mg + Fe + Mn = 0.67 to 0.82), biotite (Mg/Mg + Fe + Mn = 0.58 to 0.87) and microcline (Or/sub 96 to 100/) reflect recrystallization under low fluid pressures, relatively low f/sub O/sub 2//, and varying brine compositions. Divariant mineral assemblages in this system comprise a very low P/T facies series encompassing the clay-carbonate, zeolite, greenschist, and amphibolite facies and reflect equilibrium occurring in response to both increasing temperature and decreasing CO/sub 2/ pressure. Similar facies series, characterized by telescoped devolatization mineral reactions, are becoming increasingly recognized in other active geothermal systems above 300/sup 0/C. However, close analogues in the fossil geologic record are as yet unidentified.

  3. Large rock avalanches in southern Perù: the Cerro Caquilluco - Cerrillos Negros rock slide - avalanche (Tacna, Tomasiri, Perù)

    Science.gov (United States)

    Crosta, G.; Hermanns, R. L.; Murillo, P. V.

    2012-04-01

    The Andean bent which coincides with the Peruvian-Chilean border region is characterised by one of the largest relief contrasts on earth with depth of the subduction trench ranging from 5000 to 6000 m below sea level and mountain tops ranging from 5500 to 6300 m a.s.l.. The western flank of the Andes is subdivided in 4 major geologic zones (i.e. Coastal Cordillera, longitudinal Basin or depression, the Precordillera or western escarpment and western Cordillera). Local relief contrasts are also pronounced due to the incision of deep canyons into several million old uplifted surfaces, preserved because of the extremely dry climate with precipitation averaging a few mm and less per year. The Lluta collapse (minimum age of 2.5 Ma; volume 26 km3) is one of the largest non-volcanic non-marine landslides on Earth and has been mapped in that area (Wörner et al., 2002). Systematic mapping in northern Chile and Southern Peru has revealed that this is not the only gigantic landslide in the area but that further landslides of similar size occurred in the area, located both along the canyon slopes and along the western escarpment of the Cordillera. This suggests that landsliding has been a major factor in controlling erosion. This contribution describes first results on mapping a giant landslide complex in southern Perù called the Cerro Caquilluco - Cerrillos Negros Tomasiri rock slide - avalanche complex. The systematic mapping we have carried out in the area is presented in a further contribution to this conference. The Cerro Caquilluco - Cerrillos Negros Tomasiri rock slide - avalanche complex affected the upper part of a SW dipping paleosurface (8° to 9°) cut by a disconnected and regular primitive drainage network organized in a series of SW trending parallel valleys. This network developed within the lower Miocene pinkish tuffaceous deposits of the Huaylillas formation, whereas the main landslide scarp lies within the conglomerates of the Upper Moquegua formation

  4. [R_Arnedo_SanMiguel] Documentación geométrica de las excavaciones arqueológicas del Cerro de San Miguel (Arnedo, La Rioja). Campaña 2007

    OpenAIRE

    2007-01-01

    [ES] El cerro de San Miguel de Arnedo alberga un importante asentamiento plenamente adscrito a la cultura celtibérica. Los restos documentados corresponden a dos conjuntos de viviendas y una estructura defensiva compuesta por un foso y restos de muralla. En la presente campaña se han incorporado los restos excavados desde la documentación anterior y el perímetro del yacimiento. Además, se ha calculado el cambio de sistema de referencia de ED50 a ETRS89. [EN] San Miguel’s hill houses an ...

  5. “La parte alta del cerro es para los pequeños mineros”. Sobre la vigencia del régimen minero especial para Marmato y su influencia en la construcción de territorialidad

    Directory of Open Access Journals (Sweden)

    Gloria Patricia Lopera Mesa

    2015-12-01

    Full Text Available Este artículo examina las circunstancias que motivaron la expedición de un régimen especial para las minas de Marmato a mediados del siglo XX, el cual reserva la parte alta del cerro para el ejercicio de la pequeña minería. Asimismo, explora la vigencia de dichas normas y la manera en que ellas han influido la construcción de territorialidad y el desarrollo de una forma de vida en torno al ejercicio de la pequeña minería tradicional.

  6. Una sepultura con armas de baja época ibérica (o época romana republicana) en la necrópolis del «Cerro de las Balas» (Écija, Sevilla)

    OpenAIRE

    2000-01-01

    Iberian Iron-Age weapons are extremely rare in western Andalusia, due mainly to the absence of the normative cremation cemeteries typical of other areas in the Peninsula, cemeteries where nearly all of the approximately six thousand Iron Age weapons that we know have been documented. In this paper we present one of the very few exceptions to this rule: a ‘warrior’ burial found in the Iron Age cemetery cemetery at ‘Cerro de las Balas’ (or «bullets’ hill», so known after the many sling projecti...

  7. Sedimentología y estratigrafía de la Formación Vaca Muerta (Tithoniano-Berriasiano) en el área del cerro Domuyo, norte de Neuquén, Argentina

    OpenAIRE

    Kietzmann,Diego A; Vennari,Verónica V

    2013-01-01

    Los depósitos de la Formación Vaca Muerta en el área del cerro Domuyo muestran una interesante interca-laclón de depósitos con paleocorrientes opuestas. La unidad está representada por facies de cuenca y rampa externa con dirección de progradación hacia el oeste. Sin embargo, en su parte media se intercalan depósitos de talud, con desarrollo de deslizamientos sinsedimentarios hacia el NE, que pueden asignarse al Miembro Huncal. Este intervalo se compone de facies carbonáticas que probablement...

  8. Sedimentología y estratigrafía de la Formación Vaca Muerta (Tithoniano- Berriasiano) en el área del cerro Domuyo, norte de Neuquén, Argentina

    OpenAIRE

    Kietzmann, Diego Alejandro; Vennari, Verónica Vanesa

    2015-01-01

    Los depósitos de la Formación Vaca Muerta en el área del cerro Domuyo muestran una interesante intercalación de depósitos con paleocorrientes opuestas. La unidad está representada por facies de cuenca y rampa externa con dirección de progradación hacia el oeste. Sin embargo, en su parte media se intercalan depósitos de talud, con desarrollo de deslizamientos sinsedimentarios hacia el NE, que pueden asignarse al Miembro Huncal. Este intervalo se compone de facies carbonáticas que probablemente...

  9. Hydrothermal alteration zones and present reservoir conditions: an approach to define production zones at the eastern portion of the Cerro Prieto geothermal field, BC; Zonas de alteracion hidrotermal y condiciones actuales del yacimiento: un enfoque para determinar zonas productoras al oriente del campo geotermico de Cerro Prieto, BC

    Energy Technology Data Exchange (ETDEWEB)

    Camacho Hernandez, Juan Manuel [Comision Federal de Electricidad, Residencia General de Cerro Prieto, Mexicali, Baja California (Mexico)]. E-mail: juan.camacho02@cfe.gob.mx

    2009-07-15

    Geological factors are as essential for locating new wells as they are for defining the production zones of these wells. At the Cerro Prieto geothermal field (CGCP), one of the most important geological factors is identification of the hydrothermal alteration zones (ZAH). These are divided into silica and epidote mineralogical zones (ZMSE), without CaCO{sub 3}, and silica and epidote mineralogical transition zones (ZTMSE), with CaCO{sub 3}. It has been observed that the continuous variation of reservoir thermodynamic conditions (temperature, pressure and enthalpy) is due mainly to the exploitation of geothermal resources. The presence of new thermodynamic conditions recorded at the reservoir has led to the re-location of production wells originally located during the drilling campaign of 2004 to 2006. At the geological sections on the eastern part of the CGCP, adjustments made to the well completions lie on the limits between the ZMSE and ZTMSE zones. In turn, this is related to the current, superior, thermodynamic reservoir conditions. Based on this, a new geologic approach is proposed to define possible production zones for new wells, relating the ZAH zones to current thermodynamic reservoir conditions. [Spanish] Los factores geologicos son determinantes, tanto para establecer nuevos sitios de perforacion como para determinar el intervalo productor de un pozo nuevo. En el campo geotermico de Cerro Prieto (CGCP) una de los factores mas importantes es la determinacion de las zonas de alteracion hidrotermal (ZAH) que se dividen en dos: zona mineralogica de silice y epidota (ZMSE), sin presencia de CaCO{sub 3}, y zona de transicion mineralogica de silice y epidota (ZTMSE), con presencia de CaCO{sub 3}. Por otra parte, tambien se ha constatado que la continua variacion de las condiciones termodinamicas del yacimiento (temperatura, presion y entalpia) es originada en buena medida por la explotacion del recurso geotermico. La ocurrencia de nuevas condiciones

  10. Heat losses estimation associated with the physical state of the thermal insulation of pipes vaporductos network in Cerro Prieto geothermal field; Estimacion de perdidas de calor asociadas al estado fisico del aislamiento termico de las tuberias de la red de vaporductos del campo geotermico Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Ovando Castelar, Rosember; Martinez Estrella, Juan Ignacio; Garcia Gutierrez, Alfonso [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rovando@iie.org.mx; jime@iie.org.mx; aggarcia@iie.org.mx; Canchola Felix, Ismael; Miranda Herrera, Carlos; Jacobo Galvan, Paul [Campo Geotermico de Cerro Prieto, Comision Federal de Electricidad, Mexicali, B.C. (Mexico)

    2010-11-15

    The Cerro Prieto Geothermal Field (CPGF) steam transportation network is constituted by 140 km of pipes with diameters ranging from 8 to 48 inches, which transport the steam of 165 producing wells to 13 power plants which have a total installed capacity of 720 MWe. Originally, the pipes are thermally insulated with a mineral wool or fiber glass layer and an external aluminum or iron cover. Due to the insulation material has been exposed to weather conditions during the field operation it shows nowadays different grades of wear-out, or even it is lacking in some parts of the network, causing higher heat losses from the pipes to the environment. In this work, the magnitude of the heat losses related with the present condition of the thermal insulation throughout the pipeline network is assessed. This involved determining the longitude and diameter, as well as the insulation condition of each single pipeline section, and the calculation of the heat transfer coefficients for the different thermal insulation conditions defined for this study. [Spanish] La red de transporte de vapor del campo geotermico Cerro Prieto (CGCP) esta constituida por aproximadamente 140 km de tuberias de 8 a 48 pulgadas de diametro, las cuales conducen el vapor producido por 165 pozos hacia 13 plantas generadoras, cuya capacidad instalada es de 720 MWe. Originalmente, estas tuberias son aisladas termicamente con una capa de 2 pulgadas de material aislante a base de lana mineral o fibra de vidrio, y una proteccion exterior de aluminio o hierro. Debido principalmente al impacto de las condiciones meteorologicas durante el tiempo de operacion del campo, en algunas porciones de la red el aislante presenta actualmente distintos grados de deterioro, o incluso se encuentra ausente, lo cual se traduce en una mayor perdida de calor desde las tuberias hacia el medio ambiente. En el presente trabajo se evalua la magnitud de las perdidas de calor asociadas al estado fisico del aislamiento termico de las

  11. Nuevos datos, viejas colecciones: los conjuntos óseos de Cerro Casa de Piedra Cueva 5 (Parque Nacional Perito Moreno, Santa Cruz New data, old collections: Cerro Casa de Piedra 5 bone assemblages (Perito Moreno National Park, Santa Cruz Province, Argentina

    Directory of Open Access Journals (Sweden)

    Mariana E. De Nigris

    2007-12-01

    Full Text Available En este trabajo se presentan los resultados de un nuevo análisis de las colecciones óseas de Cerro Casa de Piedra Cueva 5, emplazado en el Parque Nacional Perito Moreno, provincia de Santa Cruz. Las muestras óseas fueron recuperadas en excavaciones sistemáticas realizadas en la década del ´80 y se ubican temporalmente en el Holoceno medio y tardío (ca. 2500-6500 años. El principal objetivo de este estudio es identificar las posibles variaciones existentes en el aprovechamiento de los recursos faunísticos con el fin de alcanzar un mayor entendimiento de las estrategias que implementaron las sociedades cazadoras recolectoras en torno a la utilización de los recursos de origen animal. Los resultados señalan al guanaco (Lama guanicoe como la especie dominante si bien el huemul (Hippocamelus bisulcus forma parte importante de la dieta. En ambos ungulados se observa un predominio del esqueleto apendicular por sobre el axial y una gran diversidad de marcas de procesamiento compatibles con situaciones de consumo. Sin embargo, a pesar de estas regularidades se han registrado también diferencias en el aprovechamiento de las presas a través del tiempo.This paper presents the results of a new analysis of bone collections from Cerro Casa de Piedra Cueva 5. The archaeological site is a large cave positioned on the north side of a volcanic hill located on the southern bank of Roble river (900 masl in a transitional area between the forest and the shrubby Patagonian steppe within the Perito Moreno National Park, northwest of Santa Cruz, Argentina. The occupational sequence is formed by four stratigraphic layers radiocarbon dated between ca. 2500 and 6500 years BP. Bone samples had been recovered during the 1980s but have received no attention since. The main aim of this paper is to identify continuities and changes in faunal resource consumption to better understand hunter-gatherer strategies during the Middle and Late Holocene. The analyzed

  12. Análisis del espacio geográfico y el paisaje de un campus universitario mexicano. Cerro de Coatepec, Universidad Autónoma del Estado de México

    Directory of Open Access Journals (Sweden)

    José Isabel Juan Pérez

    2016-01-01

    Full Text Available Este artículo es resultado de un proyecto de investigación que se realiza en todos los espacios de la Universidad Autónoma del Estado de México. Con la aplicación de fundamentos geográficos, ecológicos y técnicas de trabajo de campo (observación directa, identificación, cuantificación y registros se hizo la caracterización y el análisis del espacio geográfico, el paisaje y los cambios de uso del suelo del Cerro de Coatepec. La investigación es de tipo descriptivo y cualitativo, y se realizó a nivel de ecosistema urbano. Se demuestra que el Cerro de Coatepec es un espacio geográfico importante para los universitarios ya que desempeña múltiples funciones, pero es urgente aplicar estrategias para mitigar o compensar los impactos ocasionados al paisaje.

  13. The geochemistry and isotope hydrology of the Southern Mexicali Valley in the area of the Cerro Prieto, Baja California (Mexico) geothermal field

    Science.gov (United States)

    Portugal, Enrique; Izquierdo, Georgina; Truesdell, Alfred; Álvarez, Julio

    2005-11-01

    Groundwaters from the phreatic aquifer within and surrounding of the Cerro Prieto geothermal field were analyzed geochemically and isotopically in order to establish a hydrodynamic model of the study zone, which is located in the Mexicali Valley between 655,000-685,000 m E-W and 3,605,000-3,576,000 m N-S relative to UTM coordinates. Based on their chemical composition three types of water were recognized: chloride, sulfate and bicarbonate. However four groups of water were identified on a statistical multi-variable method of cluster analysis (A-D). The average temperature is 25 °C; with a few exceptions in the south where temperature can be as high as 47 °C. Stable isotope ratios for some waters plot close to the world meteoric line, corresponding to the original unaltered waters of the zone. The hydrogeochemistry varies in relation to three principal processes: evaporation, infiltration of water used in agriculture and rock interaction by reaction with evaporitic deposits. Major quartz, calcite and plagioclase and minor smectite, kaolinite, halite, sylvite and gypsum were identified by X-ray diffraction in lacustrine sediments of the central part of the zone. Chemical modeling indicates saturation with respect to calcite and undersaturation with respect to gypsum. By incorporating chemical and isotope data into geological and isopotential well information, a hydrodynamic model has been postulated. In this hydrodynamic model the water (A) enters the study zone from the east and it is originally of the old Colorado River water. The water samples on which the model is based were draw from agricultural wells that intersected two aquifers, a shallow and a deep one, representing the recharge to the zone. The salinity of the deep aquifer water (B) is lower than that of the shallow aquifer water (C) and so is the stable isotope ratio. The difference is though to be due to dissolution of evaporates, evaporation and possible infiltration of spent agriculture water. Both

  14. Crystallization conditions and petrogenesis of the lava dome from the ˜900 years BP eruption of Cerro Machín Volcano, Colombia

    Science.gov (United States)

    Laeger, Kathrin; Halama, Ralf; Hansteen, Thor; Savov, Ivan P.; Murcia, Hugo F.; Cortés, Gloria P.; Garbe-Schönberg, Dieter

    2013-12-01

    The last known eruption at Cerro Machín Volcano (CMV) in the Central Cordillera of Colombia occurred ˜900 years BP and ended with the formation of a dacitic lava dome. The dome rocks contain both normally and reversely zoned plagioclase (An24-54), unzoned and reversely zoned amphiboles of dominantly tschermakite and pargasite/magnesio-hastingsite composition and olivine xenocrysts (Fo = 85-88) with amphibole/clinopyroxene overgrowth, all suggesting interaction with mafic magma at depth. Plagioclase additionally exhibits complex oscillatory zoning patterns reflecting repeated replenishment, fractionation and changes in intrinsic conditions in the magma reservoir. Unzoned amphiboles and cores of the reversely zoned amphiboles give identical crystallization conditions of 910 ± 30 °C and 360 ± 70 MPa, corresponding to a depth of about 13 ± 2 km, at moderately oxidized conditions (f = +0.5 ± 0.2 ΔNNO). The water content in the melt, calculated based on amphibole chemistry, is 7.1 ± 0.4 wt.%. Rims of the reversely zoned amphiboles are relatively enriched in MgO and yield higher crystallization temperatures (T = 970 ± 25 °C), slightly lower melt H2O contents (6.1 ± 0.7 wt.%) and overlapping pressures (410 ± 100 MPa). We suggest that these rims crystallized following an influx of mafic melt into a resident magma reservoir at mid-crustal depths, further supported by the occurrence of xenocrystic olivine. Crystallization of biotite, albite-rich plagioclase and quartz occurred at comparatively low temperatures (probably rock chemistry of the CMV lava dome dacites is homogenous. They have elevated (La/Nb)N ratios of 3.8-4.5, typical for convergent margin magmas, and display several geochemical characteristics of adakites. Both Sr and Nd isotope compositions (87Sr/86Sr ˜0.70497, 143Nd/144Nd ˜0.51267) are among the most radiogenic observed for the Northern Volcanic Zone of the Andes. They are distinct from oceanic crust that has been subducted in the region

  15. Evitemos los atajos: un desglose de la relación Canadá–Estados Unidos

    Directory of Open Access Journals (Sweden)

    Daniel Schwanen

    2003-07-01

    Full Text Available This article attempts to map out the interaction between three dimensions of integration between Canada and the United States: access to markets; the integration of norms ranging from product standards to security procedures, and the control (“sovereignty” that Canada, as the much smaller partner, can realistically expect to exercise within the first two dimensions of integration. Many Canadian analysts have contended that now would be a good time for Canada to push for even greater access to the US market than that provided by the NAFTA. However, the author cautions that this push requires first a national debate on why Canada has not been more successful economically under the 1989 Canada– US Free Trade Agreement and the NAFTA. Among possible answers, the author suggests that it would be possible to adopt better domestic policies, rather than necessarily seek fully harmonization of a host of Canadian measures with those in the United States.

  16. Modelos predictivos: un atajo para describir la distribución de la diversidad biológica

    OpenAIRE

    Jorge M Lobo; Joaquín Hortal

    2003-01-01

    Para conseguir una estrategia de conservación de la diversidad biológica sustentada sobre criterios racionales, es necesario que el diseño de las redes de reservas se realice teniendo en cuenta la distribución de las especies y no, únicamente, buscando maximizar la variabilidad ambiental del territorio. Sin embargo, cuando se recopila la información disponible en las colecciones y publicaciones científicas sobre la distribución de un grupo de especies, suele ocurrir que extensas p...

  17. Determination of heat losses in the Cerro Prieto, Baja California, geothermal field steam transportation network based on the thermal insulation condition of the steam pipelines; Determinacion de perdidas de calor en la red de transporte de vapor del campo geotermico de Cerro Prieto, Baja California, con base en el estado fisico del aislamiento termico de vaporductos

    Energy Technology Data Exchange (ETDEWEB)

    Ovando Castelar, Rosember; Garcia Gutierrez, Alfonso; Martinez Estrella, Juan Ignacio [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rovando@iie.org.mx; Canchola Felix, Ismael; Jacobo Galvan, Paul; Miranda Herrera, Carlos; Mora Perez, Othon [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, B.C. (Mexico)

    2011-07-15

    In Cerro Prieto Geothermal Field (CPGF), the steam from producing wells is transported to power plants through a large and complex system of pipes thermally insulated with a 2 inches thick mineral wool or a fiber glass layer and an external aluminum or iron cover. The insulation material has been exposed to weather conditions during the field operation and has suffered density and thickness changes. In some cases the insulation has been lost completely, increasing heat transfer from the pipes to the environment. This paper analyzes the impact of the conditions of thermal insulation on heat losses in the CPGF steam-pipeline network. The heat losses are calculated by applying an iterative method to determine the surface temperature based on a heat balance calculated from the three basic mechanisms of heat transfer: conduction, convection, and radiation. Finally, using length and diameter data corresponding to the condition of the thermal insulation of each pipeline-and field operation data, the overall heat losses are quantified for steam lines throughout the pipeline network in the field. The results allow us to evaluate the magnitude of the heat losses in comparison with the overall energy losses occurring during steam transport from wells to the power plants. [Spanish] En el Campo Geotermico de Cerro Prieto (CGCP), BC, el transporte de vapor desde los pozos hasta las plantas generadoras de electricidad se lleva a cabo mediante un extenso y complejo sistema de tuberias que tipicamente se encuentran aisladas termicamente con una capa de 2 pulgadas de material aislante a base de lana mineral o fibra de vidrio, y una proteccion mecanica de aluminio o hierro galvanizado. Debido a la exposicion a las condiciones meteorologicas a traves del tiempo de operacion del campo, el aislamiento ha experimentado cambios en su densidad y espesor y en ocasiones se ha perdido por completo, lo cual repercute en una mayor transferencia de calor de las tuberias hacia el medio ambiente

  18. Jurassic tetrapods and flora of Cañadón Asfalto Formation in Cerro Cóndor area, Chubut Province Flora y tetrápodos del Jurásico de la Formación Cañadón Asfalto en el área de Cerro Cóndor, provincia de Chubut

    Directory of Open Access Journals (Sweden)

    Ignacio H. Escapa

    2008-12-01

    Full Text Available The plant and tetrapod fossil record of the Cañadón Asfalto Formation (Middle to Late Jurassic found in Cerro Cóndor area (Chubut Province is summarized here. The flora is dominated by conifers (Araucariaceae, Cupressaceae sensu lato but also includes ferns and equisetaleans. The tetrapod fauna is composed of dinosaur taxa described in the 70's as well as other remains recently described and other vertebrate groups such as amphibians, turtles, and mammals. The amphibian remains have been interpreted as representatives of a new species of Notobatrachus, considered one of the most basal members of the anuran lineage. Similarly, turtle remains have been recently recognized as a new species of basal turtle, bringing valuable information about the early evolution of this group. The dinosaur remains are largely dominated by saurischian taxa, represented by basal forms of Eusauropoda and Tetanurae. In addition, three different mammalian species have been identified and considered as early representatives of an endemic Gondwanan mammalian fauna. The fossil record of this formation represents the most completely known biota from the continental Middle to Late Jurassic of the Southern Hemisphere and one of the most complete of the entire world.Se resume brevemente el registro de plantas y tetrápodos fósiles de la Formación Cañadón Asfalto (Jurásico Medio a Superior en el área de Cerro Cóndor, provincia de Chubut. La flora está conformada por coníferas de las familias Araucariaceae y Cupressaceae sensu lato dominando la asociación, la cual se completa con helechos y equisetales en proporciones menores. La fauna de tetrápodos se compone por los clásicos dinosaurios descriptos en los 70`s, a los que se suman nuevos restos pertenecientes a este grupo, así como anfibios, tortugas y mamíferos coleccionados en la última década. Los restos de anfibios han sido interpretados como representantes de una nueva especie de Notobatrachus, considerado

  19. null Cerro Negro, Nicaragua Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This cinder cone in western Nicaragua has a name that means "black hill." It has erupted more than 20 times since its birth in 1850. Explosive eruptions from the...

  20. FLOODPLAIN, CERRO GORDO COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the...

  1. The Marianas-San Marcos vein system: characteristics of a shallow low sulfidation epithermal Au-Ag deposit in the Cerro Negro district, Deseado Massif, Patagonia, Argentina

    Science.gov (United States)

    Vidal, Conrado Permuy; Guido, Diego M.; Jovic, Sebastián M.; Bodnar, Robert J.; Moncada, Daniel; Melgarejo, Joan Carles; Hames, Willis

    2016-08-01

    The Cerro Negro district, within the Argentinian Deseado Massif province, has become one of the most significant recent epithermal discoveries, with estimated reserves plus resources of ˜6.7 Moz Au equivalent. The Marianas-San Marcos vein system contains about 70 % of the Au-Ag resources in the district. Mineralization consists of Upper Jurassic (155 Ma) epithermal Au- and Ag-rich veins of low to intermediate sulfidation style, hosted in and genetically related to Jurassic intermediate composition volcanic rocks (159-156 Ma). Veins have a complex infill history, represented by ten stages with clear crosscutting relationships that can be summarized in four main episodes: a low volume, metal-rich initial episode (E1), an extended banded quartz episode with minor mineralization (E2), a barren waning stage episode (E3), and a silver-rich late tectonic-hydrothermal episode (E4). The first three episodes are interpreted to have formed at the same time and probably from fluids of similar composition: a 290-230 °C fluid dominated by meteoric and volcanic waters (-3‰ to -0‰ δ18Owater), with <3 % NaCl equivalent salinity and with a magmatic source of sulfur (-1 to -2 ‰ δ34Swater). Metal was mainly precipitated at the beginning of vein formation (episode 1) due to a combination of boiling at ˜600 to 800 m below the paleowater table, and associated mixing/cooling processes, as evidenced by sulfide-rich bands showing crustiform-colloform quartz, adularia, and chlorite-smectite banding. During episodes 2 and 3, metal contents progressively decrease during continuing boiling conditions, and veins were filled by quartz and calcite during waning stages of the hydrothermal system, and the influx of bicarbonate waters (-6 to -8.5 ‰ δ18Owater). Hydrothermal alteration is characterized by proximal illite, adularia, and silica zone with chlorite and minor epidote, intermediate interlayered illite-smectite and a distal chlorite halo. This assemblage is in agreement with

  2. Comparison of 36Cl and 3He measurements in glacial surfaces on the tropical Altiplano (Cerro Tunupa volcano, 20°S)

    Science.gov (United States)

    Schimmelpfennig, Irene; Blard, Pierre-Henri; Lavé, Jérôme; Benedetti, Lucilla; Aster Team

    2016-04-01

    The combination of two or more cosmogenic nuclides measured in the same rock samples allow complex landscape exposure histories to be quantified, due to the nuclide-specific production and decay rates. In supposedly simple exposure scenarios, such as moraine chronologies, the use of more than one nuclide can also help identify outliers caused by geomorphological bias (e.g. "inheritance") or analytical problems (e.g. nuclide loss or contamination during chemical extraction). The two cosmogenic in situ nuclides 3He and 36Cl are potentially very useful to be simultaneously measured in quartz-lacking lithologies, but their application is more challenging than that of combined 10Be and 26Al measurements, which are routinely employed in quartz-bearing rocks. This is, amongst other things, because the production of 3He and 36Cl depend on various compositional factors. Therefore, 3He and 36Cl have rarely been measured in the same samples so far. Here, we present 36Cl measurements in plagioclases extracted from four moraine boulders and one roche moutonnée on the southern flank of Cerro Tunupa volcano, located in the tropical Bolivian Andes (3800-4500 m, 20°S). In pyroxenes of these samples, 3He has previously been measured to gain insights into the local deglaciation history and climate conditions about 15 kyr ago during the Lake Tauca highstand (Blard et al., 2009, 2013). The ages calculated from the measured 3He and 36Cl concentrations of the 5 samples range from 12 kyr to 180 kyr and are generally in good agreement. The good age agreement of a boulder surface (TU-1C) that is significantly older than the other boulder ages from this moraine confirm the suspicion, that it was exposed to cosmic radiation previous to its last deposition (Blard et al., 2009, 2013). In contrast, the 36Cl age of the roche moutonnée surface (TU2) is significantly younger than the corresponding 3He age, but fits well with the adjacent moraine mean age. It thus arises the question if the 3He

  3. An empirical calibration for {sup 4}He quantification in minerals and rocks by laser fusion and noble gas mass spectrometry using Cerro de Mercado (Durango, Mexico) fluorapatite as a standard

    Energy Technology Data Exchange (ETDEWEB)

    Sole, Jesus [Instituto de Geologia, Universidad Nacional Autonoma de Mexico, Cd. Universitaria, 04510 Mexico, D.F. (Mexico)]. E-mail: jsole@geologia.unam.mx; Pi, Teresa [Instituto de Geologia, Universidad Nacional Autonoma de Mexico, Cd. Universitaria, 04510 Mexico, D.F. (Mexico)

    2005-04-11

    An empirical calibration with a natural mineral standard (fluorapatite from Cerro de Mercado, Mexico) is proposed as a method to determine the {sup 4}He concentration of mineral and rock samples. The procedure is based on the fusion of several aliquots of the fluorapatite standard with a well-spaced weight distribution in order to obtain a good correlation in coordinates of {sup 4}He peak height versus fluorapatite weight. The weight is then converted to moles using the accepted mineral age (31.4 Ma) and appropriate formula. Experimental peak height of {sup 4}He for the unknown samples are converted to moles with the regression determined for fluorapatite. The procedure is fast and inexpensive, and both precision and accuracy are always below 10% and usually about 3-5%.

  4. Problemática histórico-metodológica del arte rupestre del Sur de la Sierra de Comechingones : El Cerro Intihuasi, Pedanía Achiras, Córdoba

    OpenAIRE

    Gili, Maria Laura

    2011-01-01

    La presente investigación consiste en un análisis sobre las pinturas rupestres del Cerro Intihuasi, ubicado en el sector sur de la región arqueológica Sierras Centrales y en el tramo sur de las Sierra de Comechingones, Pedanía Achiras, Córdoba. Nuestro interés ha sido estudiar los aspectos más relevantes en su registro y ampliar el conocimiento sobre una sociedad que se situó históricamente en una expansión temporal de tres mil años en la localidad arqueológica y su piedemonte circundante, co...

  5. Determinación de las estructuras tubulares presentes en el Pit6 en el depósito laterítico de níquel de Cerro Matoso

    OpenAIRE

    Castrillón Peña, Andrés

    2012-01-01

    Una sucesión de rocas con fósiles de organismos bentónicos en el depósito laterítico de níquel de Cerro Matoso S.A. (CMSA), localizadas en el extremo nororiental del cuerpo ultramáfico Denominado en proceso minero Pit6 a la altura del Banco 42, fueron estudiadas y analizadas Con petrografía, XRD, XRF y SEM. Estas rocas permiten precisar la génesis del yacimiento más importante de níquel en el país actualmente. La sucesión de rocas calcáreas autigénicas fosilíferas y depósitos ...

  6. The flow dynamics of an extremely large volume pyroclastic flow, the 2.08-Ma Cerro Galán Ignimbrite, NW Argentina, and comparison with other flow types

    Science.gov (United States)

    Cas, Ray A.F.; Wright, Heather M.; Folkes, Christopher B.; Lesti, Chiara; Porreca, Massimiliano; Giordano, Guido; Viramonte, Jose G.

    2011-01-01

    The 2.08-Ma Cerro Galán Ignimbrite (CGI) represents a >630-km3 dense rock equivalent (VEI 8) eruption from the long-lived Cerro Galán magma system (∼6 Ma). It is a crystal-rich (35–60%), pumice (multiple depositional units, often separated by pyroclastic surge deposits. The CGI preserves a widespread sub-horizontal fabric, defined by aligned elongate pumice and lithic clasts, and minerals (e.g. biotite). A sub-horizontal anisotropy of magnetic susceptibility fabric is defined by minute magnetic minerals in all localities where it has been analysed. The CGI is poor in both vent-derived (‘accessory’) lithics and locally derived lithics from the ground surface (‘accidental’) lithics. Locally derived lithics are small (order to explain the contemporaneous maintenance of high particle concentration, high sedimentation rate at the depositional boundary layer and a high level of mobility, it is also proposed that the flow(s) was continuously supplied at a high mass feeding rate. It is also proposed that internal gas pressure within the flow, directed downwards onto the substrate over which the flow was passing, reduced the friction between the flow and the substrate and also enhanced its mobility. The pervasive sub-horizontal fabric of aligned pumice, lithic and even biotite crystals indicates a consistent horizontal shear force existed during transport and deposition in the basal granular flow, consistent with the existence of a laminar, shearing, granular flow regime during the final stages of transport and deposition.

  7. Mega-deslizamientos de la pared sur del cerro Aconcagua y su relación con depósitos asignados a la glaciación pleistocena

    Directory of Open Access Journals (Sweden)

    Luis Fauqué

    2009-12-01

    Full Text Available Con motivo de la confección de un mapa de susceptibilidad a los procesos de remoción en masa que afectan a la localidad de Puente del Inca, se procedió a revisar la controvertida génesis del depósito Horcones. Se analizó la morfología del depósito y del paisaje circundante, la mineralogía y textura de sus materiales y finalmente se realizaron dataciones radimétricas. Sobre la base de estos estudios se concluye que el depósito de Horcones es el resultado de un flujo saturado derivado de una avalancha de rocas o mega-deslizamiento, originada por el colapso de una divisoria de aguas en la pared sur del cerro Aconcagua, durante tiempos tardioglaciales o postglaciales. Depósitos similares al de Horcones rellenan el valle del río Cuevas hacia el este y son cubiertos por otros, que también previamente fueron considerados como glaciarios (e.g. morena terminal del Drift Penitentes. El análisis de este material en las cercanías de la localidad de Penitentes, utilizando una metodología semejante, revela que corresponde a un flujo de gran envergadura proveniente de la quebrada Mario Ardito. De acuerdo a estas nuevas interpretaciones resulta clara la necesidad de realizar una exhaustiva revisión de la estratigrafía glaciaria en la zona. Surgen además nuevas ideas en cuanto a la génesis del monumento natural Puente del Inca. Finalmente, la comprensión de la evolución geomorfológica de la pared sur del cerro Aconcagua arroja luz sobre los surge del glaciar Horcones Inferior, revistiendo una gran importancia para la evaluación de los riesgos geológicos del Parque Provincial Aconcagua.

  8. Los cuerpos ígneos neógenos del cerro de Las Minas (35,3°S - 69,9°O, Cordillera Principal de los Andes, SO de Mendoza: geología, petrografía y geoquímica The Neogene igneous bodies of the Cerro de las Minas (35.3°S-69.9°W, Main Cordillera of the Andes, SW of Mendoza: geology, petrography and geochemistry

    Directory of Open Access Journals (Sweden)

    M.J. Pons

    2007-06-01

    Full Text Available El cerro de Las Minas (35,3°S - 69,9°O consiste en cuatro unidades ígneas epizonales: plutón diorítico-tonalítico, plutón granodiorítico, plutón granítico y diques -filones capa andesíticos. Estas unidades forman parte del arco magmático neógeno del SO de Mendoza correspondiente a la Andesita Huincán. Intruyen a rocas sedimentarias jurásicas de las Formaciones Puchenque y Auquilco y las que en las cercanías del contacto con los plutones diorítico y granítico, están modificadas a hornfels, calizas recristalizadas y skarns bandeados con mineralización de Fe. Geoquímicamente, constituyen un conjunto de plutones cogenéticos de amplio rango composicional, metaluminosos, subalcalinos con afinidad calcoalcalina y del tipo I, características que son semejantes a las de otros plutones de márgenes convergentes vinculados a skarns de Fe. Han evolucionado por cristalización fraccionada de sus componentes minerales principales (plagioclasa-piroxeno-anfíbol-magnetita-titanita y mezcla localizada entre los magmas diorítico y granodiorítico. Sus patrones de elementos trazas incompatibles y tierras raras son similares a los observados en las rocas ígneas: a del arco volcánico neógeno (Andesita Huincán, b vinculadas a otros skarns de Fe del SO de Mendoza (Hierro Indio y El Kaiser, c del cerro Nevazón (37,5°S perteneciente al arco volcánico paleógeno del NO de Neuquén y, finalmente, d del arco volcánico cuaternario de un sector de la zona volcánica sur (TSVZ (34,5°-37°S de los Andes, emplazados en una corteza continental relativamente delgada (35-50 km. Esto sugiere que las rocas ígneas del cerro de las Minas se formaron a partir de magmas parentales calcoalcalinos y metaluminosos, derivados de una fuente mantélica similar, con escasez o ausencia de granate residual en la fuente.The cerro de las Minas (35.3°S-69.9°W consists of four epizonal igneous units: diorite-tonalite, granodiorite and granite plutons and andesite

  9. El imperio Inka en la provincia de Catamarca

    Directory of Open Access Journals (Sweden)

    Verónica Williams

    2000-12-01

    Full Text Available La infraestructura estatal en los Andes del sur no estuvo tan ambiciosamente desarrollada como la del área al norte del Lago Titicaca. Ninguno de los centros estatales en el sur fueron tan grandes como aquellos ubicados entre el Cusco y Quito y ni las sociedades nativas fueron tan populosas y ricas como aquéllas. Los inkas construyeron una amplia red de centros provinciales y pequeños tambos protegidos por un cordón de instalaciones fortificadas que defendieron tanto los flancos orientales como meridionales. También reorganizaron las sociedades indígenas a través del reasentamiento de las poblaciones locales, la intensificación de la extracción minera, la agricultura y la producción artesanal en diversas localidades. Como la investigación se ha intensificado en años recientes, nuestro conocimiento del Kollasuyu se ha incrementado en proporción. Dos de los avances más significativos para las tierras del sur descriptos aquí concierne a la profundidad temporal y a la intensificación de la conquista inka. La cronología, la extensión y la diversidad de las instalaciones estatales indican que los inkas estuvieron presentes en momentos más tempranos que lo que tradicionalmente se consideraba e invirtieron un mayor esfuerzo en la conquista de este sector del Kollasuyu de lo que usualmente se reconoce.The state infrastructure in the South Andes was not as ambitiously developed as it was from Cusco to Quito, nor were the native societies nearly as populous or wealthy. Even so, the Inkas erected a wide array of provincial centers and smaller tampu, protected by cordons of fortified installations that defended both the southern extension of the empire and its eastern flanks. They also extensively reorganized the indigenous societies through resettlement, while intensifying mineral extraction, agricultural and craft production at numerous locations. As research has intensified over recent years, our knowledge of Kollasuyu has increased in proportion. Two of the most significant advances for the southern lands described here concern the time depth and intensity of Inka rule. The chronology, extent, and diversity of the state installations indicate that the Inkas were present earlier and invested far more effort in ruling the south than is usually recognized.

  10. Estratigrafía, análisis de facies y paleoambientes de la formación cañadón asfalto en el depocentro jurásico cerro Cóndor, provincia del Chubut Stratigraphy, facies analysis and paleoenvironments of the Cañadón Asfalto Formation, Jurassic Cerro Cóndor depocenter, Chubut province

    Directory of Open Access Journals (Sweden)

    Nora Cabaleri

    2010-05-01

    Full Text Available El depocentro Cerro Cóndor representa la secuencia estratigráfica del Jurásico continental más completa de la cuenca de Cañadón Asfalto y de Sudamérica austral. Se sitúa en la Patagonia extraandina, en ambas márgenes del río Chubut medio. La sedimentación en esta cuenca pull apart, acompañada por efusiones de basalto olivínico, comenzó en el Jurásico Medio temprano. Predominan en la Formación Cañadón Asfalto los depósitos lacustres caracterizados por asociaciones de facies carbonáticas y siliciclásticas intercaladas con rocas lávicas en la base y depósitos piroclásticos hacia el techo de la unidad. Se describe el desarrollo de facies a lo largo de un corte norte-sur que abarca las secciones de estancia El Torito y de los cañadones Los Loros, Las Chacritas, Carrizal, Asfalto y Lahuincó. Las facies/microfacies carbonáticas están representadas por mudstones, wackestones,packstones, grainstones y calizas microbialíticas características de ambientes litorales, marginales y palustres. En la Formación Cañadón Asfalto se distinguen un miembro inferior (Las Chacritas, constituido por calizas, lutitas, areniscas y conglomerados, intercalados con basaltos olivínicos y por otro superior (Puesto Almada compuesto por tobas, tufitas, lutitas y areniscas. El primero es portador de una asociación palinológica de edad bajociano-bathoniana y el segundo de dinosaurios de edad tithoniana. Se describen detalladamente e ilustran las secciones estratigráficas de ambos miembros de la formación en sus localidades tipo, cañadón Las Chacritas y estancia el Torito y se reconstruyen los paleoambientes del depocentro desde el Aaleniano al Tithoniano. La edad del miembro Puesto Almada en su localidad tipo se obtuvo mediante una datación radimétrica (K/Ar de biotitas provenientes de una delgada capa de toba volcánica (147,1 ± 3,3 Ma, Tithoniano proveniente de la parte superior de la unidad.The Cerro Cóndor depocenter represents the

  11. Una sepultura con armas de baja época ibérica (o época romana republicana en la necrópolis del «Cerro de las Balas» (Écija, Sevilla

    Directory of Open Access Journals (Sweden)

    Núñez Pariente de León, Esther

    2000-12-01

    Full Text Available Iberian Iron-Age weapons are extremely rare in western Andalusia, due mainly to the absence of the normative cremation cemeteries typical of other areas in the Peninsula, cemeteries where nearly all of the approximately six thousand Iron Age weapons that we know have been documented. In this paper we present one of the very few exceptions to this rule: a ‘warrior’ burial found in the Iron Age cemetery cemetery at ‘Cerro de las Balas’ (or «bullets’ hill», so known after the many sling projectiles found in the neighbourhood. This is an important find due to three facts: the type of weapons (among them a sword of the gladius hispaniensis type and a dagger of a very late Celtiberian or very early Roman type; the date, between the Late Iberian period and Early Roman rule; and the closed assemblage of weapons: sword, dagger and two javelins or short spears. It is quite possible that the burial is to be dated to the beginning of the second century BC, and therefore that the sword found in it is the earliest known example of the Roman gladius hispaniensis sword... or the latest version of the Iberian prototype for it. Finally, we discuss the proximity of this burial to the caesarian battlefield of Munda (45 BC to conclude that in all probability these are two completely independent events, the burial being probably much earlier.

    Las armas de época ibérica son rarísimas en Andalucía Occidental, en buena parte debido a la práctica ausencia de necrópolis, que es donde las armas se han documentado en mayor número durante toda la Edad del Hierro peninsular. Se presenta en este trabajo una de las pocas excepciones a esta regla: una sepultura ‘de guerrero’ hallada en la necrópolis del ‘Cerro de las Balas’ (así llamado por los numerosos proyectiles de honda hallados en las cercanías. Es un hallazgo de importancia por el tipo de armas hallado (entre ellas una espada de hoja recta del tipo del

  12. Evolución petrotectónica del distrito minero Cerro Áspero y modelo de emplazamiento de los depósitos wolframíferos, Córdoba

    Directory of Open Access Journals (Sweden)

    D. Mutti

    2005-03-01

    Full Text Available La geología relacionada con la intrusión granítica Cerro Áspero expone en el faldeo oriental de la sierra de Comechingones, mineralización metalífera diseminada y en brechas hidráulicas, conectada genéticamente a un grupo minero integrado por un sistema de enjambres de venas, vetas y mantos cuarzosos con direcciones NNO, ONO y N. La comarca presenta polimetamorfismo y al menos, dos eventos de cizallamiento simple (D3 y D4 y estructuras penetrativas (S2, S3 y S4 que se desarrollaron desde el Pampeano hasta el Famatiniano inclusive, favoreciendo la intrusión anorogénica del batolito Cerro Áspero a partir del Devónico tardío. Como consecuencia del evento magmático fueron reactivadas las estructuras, movilizando fluidos hidrotermales por las anisotropías del terreno y debajo de un nivel de anfibolitas macizo que actuó como una barrera impermeable. La acción de un esfuerzo máximo s1 (330º contribuyó al desarrollo del sistema mineralizado siguiendo el patrón de fracturamiento del modelo de Riedel y propició la construcción del lineamiento mineral principal en una faja de cizalla simple dextral de posición 285º (S5. El fluido magmático - hidrotermal evolucionó mediante numerosos pulsos de ruptura y apertura de las inhomogeneidades rocosas, con sellado de cavidades por mecanismos de cierre con fracturamiento y relleno y disolución por presión. Estos mecanismos precipitaron sílice con hábito fibroso y reconcentraron elementos metálicos bajo un régimen de tracción y presión de fluido de poro estimada en 195 MPa. La edad de la mineralización de uno de sus estadios fue determinada en 343,8 ± 10,8 Ma, mediante una datación K/Ar en muscovita.

  13. Edad y rasgos petrográficos y geoquímicos de cuerpos subvolcánicos asignables a la Formación Cerro León, este del Macizo del Deseado, Santa Cruz

    Directory of Open Access Journals (Sweden)

    D. Guido

    2004-12-01

    Full Text Available Se presentan nuevos afloramientos de cuerpos subvolcánicos correlacionables con la Formación Cerro León en el sector oriental del Macizo del Deseado. Esta unidad aflora en dos sectores, en el bajo Leonardo y en el afloramiento Bahía Laura del Complejo Río Deseado. El primer sector presenta trece diques y un filón capa intruyendo a las sedimentitas pérmicas de la Formación La Golondrina y el segundo sector comprende tres diques que intruyen a rocas del basamento. Se trata de rocas de color gris a negro, frecuentemente alteradas, con textura microgranuda a porfírica, con fenocristales de plagioclasa, diópsido (En42 Fs11 Wo47 y en menor medida de hornblendas ricas en Mg (magnesio hastingsita, en una matriz holocristalina de textura intergranular. Son rocas subalcalinas de composiciones basalto-andesita y con afinidades calcoalcalinas. La edad Ar/Ar obtenida en una de estas muestras (180,1±1,5 Ma representa la primer determinación realizada en esta unidad y es coherente con las relaciones estratigráficas observadas para esta formación. La comparación con rocas ígneas jurásicas de la provincia geológica Macizo del Deseado, favorece la vinculación temporal y genética con el evento volcánico-piroclástico del Jurásico medio a superior (Formación Bajo Pobre y Grupo Bahía Laura. Sin embargo, la diferencia en las edades Ar/Ar, sugieren una interrupción entre el evento subvolcánico (180 Ma y el volcanismo Jurásico medio a superior (177 a 150 Ma. Se considera, preliminarmente, que los cuerpos subvolcánicos de la Formación Cerro León representarían las primeras evidencias magmáticas del rift jurásico en el Macizo del Deseado.

  14. From the Copper Age to the Bronze Age in the Lower Guadalquivir Basin. The Cerro de San Juan settlement (Coria del Río, Seville, Spain and the ‘replacement model’

    Directory of Open Access Journals (Sweden)

    Daniel GARCÍA RIVERO

    2015-11-01

    Full Text Available The transition between Copper and Bronze Ages in the Southwest of the Iberian Peninsula is poorly known still, especially when compared with the transition between Los Millares culture to El Argar culture in the Southeast. The settlement of Cerro de San Juan, which controlled the Guadalquivir mouth at that time, shows some evidences of human occupations of both periods, an uncommon feature along the South of Iberian Peninsula. The data from this site suggest a sedimentary break between the two periods, and a strong cultural change as well. The culture material sets are different between the Bell Beaker phase and the Bronze Age, and several radiocarbon dates define consistently the chronology of the phenomenon. From this perspective, an analysis of every archaeological stratigraphy that has evidences of both periods is carried out. Against a model of cultural continuity, numerous archaeological features rather suggest a model of demographic replacement. Thus, the Bronze Age can be defined as a new way of life perhaps by human groups that were not direct descendants of the previous communities.

  15. Geomorphology, internal structure, and successive development of a glacier foreland in the semiarid Chilean Andes (Cerro Tapado, upper Elqui Valley, 30°08‧ S., 69°55‧ W.)

    Science.gov (United States)

    Monnier, Sébastien; Kinnard, Christophe; Surazakov, Arzhan; Bossy, William

    2014-02-01

    We use geomorphological analysis, sedimentological survey, remote sensing, and ground penetrating radar (GPR) in order to understand the complex landform assemblage found in front of the Cerro Tapado glacier in the upper Elqui River catchment, semiarid Andes of Chile. The geomorphological analysis highlights prominent boundaries dividing the landform assemblage into (from the upper part to the lower part) an upper latero-frontal moraine complex, an upper debris-covered glacier, a lower debris-covered glacier, two rock glaciers, and a lower morainic complex. The sedimentological survey highlights the rather small size of the surface debris (in general 400 m) receding of the glacier occurred, along with downslope displacements (dm-m·y- 1) of most of the landform units and a significant evolution of the thermokarst features on the debris-covered glaciers. Considerable surface lowering occurred in the upper part of the assemblage, while localized bulging is seen along the morphological boundaries in the lower units. The GPR profiles highlight spectacular internal structure in the upper debris-covered glacier with up to 80 m of buried ice. In the other landform units, the internal structure is less visible and more heterogeneous. The analysis of the radar wave velocity along the GPR profiles reveals the occurrence of air-filled and moist zones in the internal structure. The geomorphological assemblage is fundamentally characterized by its morphological, structural, and dynamical boundaries and defined as a young (probably rock glaciers do not derive from the present debris-covered glacier but preexist to it.

  16. PRIMEROS RESULTADOS SOBRE EL USO PREHISPÁNICO DE LOS VEGETALES EN EL SITIO ARQUEOLÓGICO LOS TRES CERROS 1 (VICTORIA, ENTRE RÍOS, ARGENTINA: ANÁLISIS DEL REGISTRO BIOSILÍCEO.

    Directory of Open Access Journals (Sweden)

    Jorge O. Sánchez

    2013-01-01

    Full Text Available El registro de microfósiles biosilíceos posee un alto grado de preservación en distintos contextos naturales y culturales. Por esta razón, el estudio de los fitolitos y otros microrrestos biosilíceos puede contribuir a determinar las condiciones ambientales de las comunidades vegetales que rodearon un sitio arqueológico, así como también identificar especies vegetales domesticadas. En esta contribución se rea- lizó el análisis de fitolitos en el marco de otros bioindicadores de los depósitos superiores de la secuencia sedimentaria antrópica del sitio Los Tres Cerros 1 (LTC1, isla Las Moras, Departamento Victoria, Entre Ríos, Argentina. Los análisis desarrollados permitieron identificar morfotipos silíceos relacionados con la presencia de vegetales silvestres que caracterizan a la unidad fitogeográfica actual del área de em- plazamiento, y morfotipos silíceos asignables a recursos vegetales de interés cultural, pertenecientes a las familias Arecaceae, Cucurbitaceae, y Poaceae (subfamilias Maideae y Oryzoideae. El registro de microfósiles biosilíceos del perfil del sitio LTC1 tiene un cambio neto que puede ser correlacionado con diferentes actividades culturales desempeñadas durante el proceso de construcción del montículo, que tuvo lugar durante ca.1000 - 500 años 14C AP.

  17. El complejo deslizamiento de Ailinco-Cerro Papas-Las Olletas (Departamento Minas, norte del Neuquén, Argentina The complex landslide of Ailinco-Cº Papas-Las Olletas, northern Neuquén, Argentina

    Directory of Open Access Journals (Sweden)

    E.F. González Díaz

    2003-06-01

    Full Text Available De acuerdo a los antecedentes disponibles, acumulaciones de aspecto tilloide que conforman el irregular paisaje de un amplio sector de la cuenca de drenaje del arroyo Ailinco y que se extiende al pie del extremo sur de la serranía de la Puntilla y del faldeo oeste del Cº Papas y en el paraje de las Olletas, han sido consideradas como propias de la génesis glaciaria (morenas; tills. Los autores las interpretan como correspondientes a depósitos de un complejo conjunto local de grandes movimientos gravitacionales, en el que se han distinguido tres avalanchas de rocas, siendo las mayores aquellas del Cº Las Papas y de Ailinco y otra de menor porte ocurrida en la zona de Las Olletas. Sólo se describe su distribución y sus principales características morfológicas Se propone como el promotor de los mismos a la energía sísmica, teniendo en cuenta las condiciones sismotectónicas de la región y antecedentes de otros similares movimientos cercanos, ya analizados por los autores En el mapa geomorfológico adjunto, que cubre prácticamente la totalidad del área de las cuencas de los arroyos Ailinco y Manchana Covunco, se distinguen la presencia y distribución de otras geoformas menores, cuyo origen está relacionado con procesos propios de la morfogenia glaciaria, de un ambiente local de condiciones periglaciarias actuales y de la remoción en masa.At the southern end of the Sierra de la Puntilla Range in northern Neuquén province, extensive deposits of "tilloid" features in a morphological environment with hummocky-topography were observed. Previous studies suggest their relation with glacial morphogenesis (moraines; tills. We propose instead here their relationship to large gravitational movements triggered by seismic shock, and we distinguish two rock-avalanches and a third considered as a minor landslide. The most important is the "Cerro Papas rock-avalanche" which occurred on its western slope. The "Ailinco rock-avalanche" is situated on

  18. Estratigrafía, análisis de facies y paleoambientes de la formación cañadón asfalto en el depocentro jurásico cerro Cóndor, provincia del Chubut

    Directory of Open Access Journals (Sweden)

    Nora Cabaleri

    2010-05-01

    Full Text Available El depocentro Cerro Cóndor representa la secuencia estratigráfica del Jurásico continental más completa de la cuenca de Cañadón Asfalto y de Sudamérica austral. Se sitúa en la Patagonia extraandina, en ambas márgenes del río Chubut medio. La sedimentación en esta cuenca pull apart, acompañada por efusiones de basalto olivínico, comenzó en el Jurásico Medio temprano. Predominan en la Formación Cañadón Asfalto los depósitos lacustres caracterizados por asociaciones de facies carbonáticas y siliciclásticas intercaladas con rocas lávicas en la base y depósitos piroclásticos hacia el techo de la unidad. Se describe el desarrollo de facies a lo largo de un corte norte-sur que abarca las secciones de estancia El Torito y de los cañadones Los Loros, Las Chacritas, Carrizal, Asfalto y Lahuincó. Las facies/microfacies carbonáticas están representadas por mudstones, wackestones,packstones, grainstones y calizas microbialíticas características de ambientes litorales, marginales y palustres. En la Formación Cañadón Asfalto se distinguen un miembro inferior (Las Chacritas, constituido por calizas, lutitas, areniscas y conglomerados, intercalados con basaltos olivínicos y por otro superior (Puesto Almada compuesto por tobas, tufitas, lutitas y areniscas. El primero es portador de una asociación palinológica de edad bajociano-bathoniana y el segundo de dinosaurios de edad tithoniana. Se describen detalladamente e ilustran las secciones estratigráficas de ambos miembros de la formación en sus localidades tipo, cañadón Las Chacritas y estancia el Torito y se reconstruyen los paleoambientes del depocentro desde el Aaleniano al Tithoniano. La edad del miembro Puesto Almada en su localidad tipo se obtuvo mediante una datación radimétrica (K/Ar de biotitas provenientes de una delgada capa de toba volcánica (147,1 ± 3,3 Ma, Tithoniano proveniente de la parte superior de la unidad.

  19. La avalancha de rocas del cerro Los Cardos (37°10´S,70°53´O en la región norte de la provincia del Neuquén The rock avalanche of Cerro Los Cardos (37° 10´S, 70° 53´ W in the northern region of the province of Neuquén

    Directory of Open Access Journals (Sweden)

    E.F. González Díaz

    2005-03-01

    Full Text Available Se describe una nueva e importante avalancha de rocas, no reconocida hasta ahora, localizada a unos 25 km al oeste de la población de Andacollo. Muestra dos cicatrices o muescas de desprendimiento, de las cuales la austral es interpretada como la muesca principal de su desprendimiento y se halla al pie del borde occidental de una planicie estructural lávica, sobre cuyo extremo norte se ubica el cerro Los Cardos. Es un complejo movimiento, con numerosas escarpas de arranque internas en la masa movilizada, consideradas secundarias, las que al igual que la principal, tienen una general orientación noroeste-sureste. Su mecánica aparenta haberse iniciado como un movimiento translacional (planar a favor de la disposición casi vertical, con fuerte buzamiento hacia el oeste de las capas de la Formación Lileo. Sin embargo, la disposición espacial (cóncavas que adoptan las distintas muescas de arranque (tanto principales como secundarias, permite sugerir un desarrollo y continuación del movimiento como afín a un deslizamiento rotacional. A partir del desprendimiento austral el movimiento general se orientó hacia el sur, hacia el valle del arroyo Lileo, presumiblemente en sucesivos pulsos, identificables por escarpas de arranque internas. En el correspondiente al septentrional el desplazamiento se dirigió hacia el oeste hacia el valle del arroyo Palao. Con posterioridad el movimiento parece estar controlado por la pendiente de dicho valle hacia la afluencia al arroyo Lileo. La porción distal de sus acumulaciones alcanzó a trepar (run-up, el lateral opuesto del valle del arroyo Palao. La laguna de los Rojos se halla en una depresión supuestamente generada por el deslizamiento y fracturamiento de un bloque rocoso desprendido de la planicie estructural lávica de Los Cardos. Diversos factores intrínsecos, establecieron previamente al fenómeno condiciones favorables para el desprendimiento. Se propone como promotor de la avalancha de rocas a

  20. Cerro Prieto geothermal field: exploration during exploitation

    Energy Technology Data Exchange (ETDEWEB)

    1982-07-01

    Geological investigations at Momotombo included photogeology, field mapping, binocular microscope examination of cuttings, and drillhole correlations. Among the geophysical techniques used to investigate the field sub-structure were: Schlumberger and electromagnetic soundings, dipole mapping and audio-magnetotelluric surveys, gravity and magnetic measurements, frequency domain soundings, self-potential surveys, and subsurface temperature determinations. The geochemical program analyzed the thermal fluids of the surface and in the wells. The description and results of exploration methods used during the investigative stages of the Momotombo Geothermal Field are presented. A conceptual model of the geothermal field was drawn from the information available at each exploration phase. The exploration methods have been evaluated with respect to their contributions to the understanding of the field and their utilization in planning further development.

  1. HYDROLOGY, CERRO GORDO COUNTY, IA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydrology data include spatial datasets and data tables necessary for documenting the hydrologic procedures for estimating flood discharges for a flood insurance...

  2. TERRAIN, CERRO GORDO COUNTY, IOWA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  3. Geothermal well drilling manual at Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez P., A.; Flores S., M.

    1982-08-10

    The objective of the drilling manual is to solve all problems directly related to drilling during the construction of a well. In this case, the topics dealt which are drilling fluids and hydraulics to be applied in the field to improve drilling progress, eliminate risks and achieve good well-completion. There are other topics that are applicable such as drill bits and the drilling string, which are closely linked to drilling progress. On this occasion drilling fluid and hydraulics programs are presented, in addition to a computing program for a Casio FX-502P calculator to be applied in the field to optimize hydraulics and in the analysis of hydraulics for development and exploration wells at their different intervals.

  4. Hydrography, Published in 2008, Cerro Gordo County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Hydrography dataset, was produced all or in part from Hardcopy Maps information as of 2008. Data by this publisher are often provided in State Plane coordinate...

  5. Los cuerpos ígneos neógenos del cerro de Las Minas (35,3°S - 69,9°O, Cordillera Principal de los Andes, SO de Mendoza: geología, petrografía y geoquímica

    Directory of Open Access Journals (Sweden)

    M.J. Pons

    2007-06-01

    Full Text Available El cerro de Las Minas (35,3°S - 69,9°O consiste en cuatro unidades ígneas epizonales: plutón diorítico-tonalítico, plutón granodiorítico, plutón granítico y diques -filones capa andesíticos. Estas unidades forman parte del arco magmático neógeno del SO de Mendoza correspondiente a la Andesita Huincán. Intruyen a rocas sedimentarias jurásicas de las Formaciones Puchenque y Auquilco y las que en las cercanías del contacto con los plutones diorítico y granítico, están modificadas a hornfels, calizas recristalizadas y skarns bandeados con mineralización de Fe. Geoquímicamente, constituyen un conjunto de plutones cogenéticos de amplio rango composicional, metaluminosos, subalcalinos con afinidad calcoalcalina y del tipo I, características que son semejantes a las de otros plutones de márgenes convergentes vinculados a skarns de Fe. Han evolucionado por cristalización fraccionada de sus componentes minerales principales (plagioclasa-piroxeno-anfíbol-magnetita-titanita y mezcla localizada entre los magmas diorítico y granodiorítico. Sus patrones de elementos trazas incompatibles y tierras raras son similares a los observados en las rocas ígneas: a del arco volcánico neógeno (Andesita Huincán, b vinculadas a otros skarns de Fe del SO de Mendoza (Hierro Indio y El Kaiser, c del cerro Nevazón (37,5°S perteneciente al arco volcánico paleógeno del NO de Neuquén y, finalmente, d del arco volcánico cuaternario de un sector de la zona volcánica sur (TSVZ (34,5°-37°S de los Andes, emplazados en una corteza continental relativamente delgada (35-50 km. Esto sugiere que las rocas ígneas del cerro de las Minas se formaron a partir de magmas parentales calcoalcalinos y metaluminosos, derivados de una fuente mantélica similar, con escasez o ausencia de granate residual en la fuente.

  6. Spatio-temporal evolution of anthropogenic deformation around Cerro Prieto geothermal field in the Mexicali Valley, B.C., Mexico, between 1993 and 2009 from DInSAR and leveling.

    Science.gov (United States)

    Sarychikhina, Olga; Glowacka, Ewa; Robles, Braulio; Mojarro, Jose

    2014-05-01

    Land subsidence is an environmental hazard which could be caused by withdrawal of large amounts of fluid from beneath the earth's surface. Land subsidence is an issue in several geothermal fields worldwide (e.g., Geysers, USA (Mossop and Segall, 1997), Wairakei-Tauhara, New Zealand (Allis et al., 2009)). Cerro Prieto geothermal field (CPGF), located in the Mexicali Valley, northwest Mexico, is the oldest and largest Mexican geothermal field in operation and has been producing electricity since 1973. The large amount of geothermal fluids extracted to supply steam to the power plants has resulted in considerable deformation in and around the field (e.g. Glowacka et al., 1996, 1999; Carnec and Fabriol, 1999; Sarychikhina et al., 2011). The deformation includes land subsidence and related ground fissuring and faulting. These phenomena have produced severe damages to the local infrastructure such as roads, irrigation canals and other facilities. Detection of land subsidence and monitoring of the spatial and temporal changes of its pattern and magnitude can provide important information about the dynamics of this process and controlling geological structures. The technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) has been demonstrated to be a very effective technique for measuring ground deformation. This study presents an application of DInSAR interferogram stacking technique to investigate the land subsidence in the Mexicali Valley near CPGF. C-band ENVISAR ASAR images acquired between 2003 and 2009 from the ascending (track 306, frame 639) and descending track (track 84, frame 2961), obtained from the European Space Agency (ESA), as part of ESA CAT-1 project (ID - C1P3508), were used. Gamma ISP and DIFF/GEO software packages were used to calculate differential interferograms from SLC data and for differential interferograms stacking (Wegmüller and Werner, 1997). Eight average annual deformation rate maps were generated for 2005 (descending

  7. Metallogenic model of the Las Termas uranium deposit at Fiambala, Province of Catamarca, Argentina; Modelo metalogenetico del yacimiento de uranio Las Termas, Fiambala, Catamarca, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Morello, O.; Rubinstein, N.; Hongn, F.; Ferreira, L.; Anesa, J.; Arias, A.

    2011-07-01

    The Las Termas uranium-ore deposit, located in the geological province of Sierras Pampeanas, Argentina, is contained within the Precambrian metamorphic basement close to the contact with the Los Ratones Carboniferous granite. This deposit was originally linked to greisenization associated with Carboniferous magmatic activity. Nevertheless, recent data concerning pitchblende-type uraninite (113.6 Ma and 51.4 Ma) and the spatial relationship between the mineralization and Cretaceous rifting volcanism lead us to suggest a new genetic model, developed in two stages. During the first stage Carboniferous greisenization included the leaching of uranium from granite, whilst during the second stage Cretaceous rift-magmatism led to a hydrothermal system, which would have been responsible for uranium mineralization. (Author)

  8. Petrología y estructura de la faja de deformación La Chilca, Catamarca Petrology and structure of La Chilca Shear Zone, Catamarca

    Directory of Open Access Journals (Sweden)

    Mariano A. Larrovere

    2008-06-01

    Full Text Available Los estudios de campo, petrológicos y estructurales permitieron definir y caracterizar una zona de cizalla dúctil sobre el basamento metamórfico de las Sierras Pampeanas noroccidentales. La faja de deformación La Chilca se extiende en dirección nornoroeste por unos 24 kilómetros de largo y un ancho de 1 a 4 kilómetros sobre el límite austral de la sierra de Aconquija y su prolongación hacia el sur sobre la parte septentrional de la sierra de Ambato. Está compuesta por milonitas, protomilonitas y blastomilonitas que son el producto de la deformación dúctil que afectó al basamento metamórfico conformado originalmente por migmatitas y gneises. Las condiciones metamórficas durante la deformación alcanzaron la facies de esquistos verdes hasta la facies de anfibolita, con temperaturas de entre 350 a 500ºC. La foliación milonítica C predominante posee una orientación general N 330°/42° ENE, plano sobre el cual se desarrollan las lineaciones de estiramiento mineral con una orientación media de N 68°/42°. Determinamos para la esta faja de cizalla movimientos generales de carácter inverso, con desplazamientos del techo hacia el suroeste (N248°. Rasgos locales internos de carácter normal sugieren una mayor complejidad en la cinemática de deformación.Field, petrological and structural studies allowed to define and and to characterize a ductile shear zone on the metamorphic basement of the northwestern Sierras Pampeanas. La Chilca Shear Zone has a NNW trend for about 24 km and a width of 1-4 km in the southern border of the Sierra de Aconquija and northern part of the Sierra de Ambato. It is composed by mylonites, protomylonites and blastomylonites that are the product of the ductile deformation that affected the metamorphic basement originally composed by migmatites and gneisses. The metamorphic conditions during the deformation reached greenschist facies to amphibolite facies, with temperatures around 350 to 500 ºC. The dominant mylonitic foliation C is generally trending N 330°/42° ENE. On this plane there is a stretching mineral lineation of N68°/42°. Reverse displacements toward the southwest (N 248° were determined for this shear zone. Internal local features of direct displacements suggest some complexities in the deformation kinematics.

  9. ARQUITECTURA Y PAISAJES EN LA LOCALIDAD ARQUEOLÓGICA DE ANDALHUALA (VALLE DE YOCAVIL, CATAMARCA / Architecture and landscape in Andalhuala archaeological locality (Yocavil Valley, Catamarca

    Directory of Open Access Journals (Sweden)

    Alina Alvarez Larrain

    2010-12-01

    Full Text Available El espacio arquitectónico se constituye como parte del paisaje cultural que participa de lleno en la construcción y reproducción de las prácticas domésticas y rituales y del imaginario colectivo de la comunidad que lo construye y lo habita. La localidad arqueológica de Andalhuala se presenta así como un área que nos permite abordar cómo fue la construcción y el uso del espacio en la vertiente oriental del valle de Santa María o Yocavil, cuyos patrones de asentamiento fueron anteriormente definidos a partir de lo conocido para el flanco occidental. Se discuten aquí las evidencias recuperadas a partir de tareas de prospección y relevamiento arquitectónico en la mencionada localidad. Los resultados obtenidos hasta ahora revelan un panorama complejo de ocupaciones desde los inicios del primer milenio D.C. hasta los finales de los tiempos tardíos, abarcando una franja espacial desde los terrenos bajos próximos a cuencas permanentes hasta los pisos inferiores de la Sierra del Aconquija.Palabras clave: Valle de Yocavil; localidad arqueológica de Andalhuala ; sociedades agropastoriles; paisajes arqueológicos; variabilidad de asentamientos.AbstractThe architectural space is set up as part of the cultural landscape is fully involved in the construction and reproduction of domestic and ritual practices and the collective imagination of the community that builds and inhabits it. The Andalhuala archaeological locality is thus presented as an area that allows us to consider what was the construction and use of space on the eastern slope of the valley of Santa Maria or Yocavil whose patterns of settlement were previouly identified from the known to the western flank. We discuss here the evidence recovered from prospecting and surveying architectural in the mentioned locality. The results so far indicate a complex picture of occupations since the beginning of the first millennium D.C. until the final of the late times, comprising a strip space from the lowlands near permanent basins to the lower floors of the Sierra del Aconquija.Keywords: Yocavil Valley; Andalhuala archaeological locality; agropastoral societies; archaeological landscape; variability of settlements.

  10. Paracas geoglyphs of the peruvian south coast: Cerro Lechuza and Cerro Pico

    OpenAIRE

    García Soto, Rubén

    2015-01-01

    Traditionally, the manufacture of large found drawings on desert plains and hill slopes of the Peruvian south coast was at-tributed to the Nasca society. However, since the 1980s, it is known that this cultural manifestation is a tradition that wouldhave begun towards the 750 BC during the early part of the development of the Paracas culture. Paracas geoglyphs have beenreported from Pisco to the Rio Grande Basin of Nasca, particularly in the area of Palpa where the where they have identifiedm...

  11. ¿Quién está contra quién en los cerros orientales de Bogotá? La perspectiva local desde el barrio la Cecilia = Who is against who in the eastern hills of Bogotá? The local perspective from the neighborhood of la Cecilia

    Directory of Open Access Journals (Sweden)

    Ana María López Ortego

    2016-09-01

    Full Text Available Este trabajo aborda las controversias medioambientales, jurídicas y habitacionales que confluyen en el área de reserva medioambiental de los Cerros Orientales de Bogotá. La lógica socio-urbanística de la ciudad -ligada a las urbanizaciones piratas y la invasión-; los movimientos migratorios -acentuados por el conflicto armado- y la falta de definición de una política pública clara en los últimos 30 años, ha desembocado en un conflicto entre pobladores, organizaciones civiles de defensa del medioambiente, empresas privadas e instituciones públicas, mediados casi exclusivamente por resoluciones judiciales puntuales. Este trabajo recoge -a través de fuentes secundarias- las que se consideran principales iniciativas y acciones de gobierno impartidas de arriba a abajo (Top Down e investiga -a través de fuentes primarias recogidas en el barrio La Cecilia-, las percepciones territoriales e iniciativas de acción comunitaria de abajo a arriba (Bottom up, indagando en los estériles procesos de diálogo entre estas dos formas de hacer ciudad.This paper addresses the environmental, legal and housing disputes that converge in the environmental reserve located at the Cerros Orientales (eastern hills of Bogota. The socio-urban logic of the city -linked to pirate developments and invasion-, the migration flows -emphasized by the armed conflict- and the lack of definition of a clear public policy for the last 30 years, has led to a conflict between residents, civil environmental protection organizations, private companies and public institutions in which almost only specific judgments have interceded. This paper duly reflects -through secondary sources- those considered main government initiatives and actions implemented with a top-down approach and it investigates -through primary sources collected in the neighborhood La Cecilia- the bottom-up community action initiatives and territorial perceptions, looking into

  12. Un corredor verde entre cerros desde 1934, y las posibilidades actuales desde un ejercicio académico de pregrado en Recoleta./ A green corridor between the hills since 1934, and its current possibilities, explored through an undergraduate academic exercise in Recoleta

    Directory of Open Access Journals (Sweden)

    María Isabel Pavez Reyes

    2013-12-01

    Full Text Available En el marco de una investigación FAU –U. Chile, “El antiguo sector de La Chimba: en defensa de sus vestigios patrimoniales, una vida comunitaria de escala barrial y un futuro ambiente sustentable” , y la reconsideración de una proposición de Karl Brunner en Recoleta, un grupo de estudiantes exploran un polígono del pericentro norte de Santiago, presentando las posibilidades y limitaciones actuales para lograr una cierta continuidad verde entre los cerros San Cristóbal y Blanco en la perspectiva de una renovación con mayor sustentabilidad urbana./ This article is part of the research project entitled “The old area of La Chimba: in defense of its heritage traces, a neighborhood scale community life and a sustainable environment for the future” (funded through the Universidad de Chile’s Faculty of Architecture and Urbanism research fund. A group of undergraduate architecture students revisit a proposition made by Karl Brunner for Recoleta, exploring the possibilities and limitations to achieve a continuity of green spaces between the San Cristobal and Blanco hills, from an urban sustainability perspective.

  13. Discussion of 'Geomorphology, internal structure, and successive development of a glacier foreland in the semiarid Chilean Andes (Cerro Tapado, upper Elqui Valley, 30°08‧ S, 69°55‧ W.)', by S. Monnier, C. Kinnard, A. Surazakov and W. Bossy, Geomorphology 207 (2014), 126-140

    Science.gov (United States)

    Nobes, David C.

    2015-12-01

    Recently, Monnier et al. (2014, Geomorphology 207, 126-140) suggested that diffraction events with air-wave velocities along profile CD were caused by an air-filled void at depth within one of the glaciers of the Cerro Tapado, Chile. This is not physically possible. The velocity at which radar travels to and from the scattering feature that causes a diffraction is at the velocity that surrounds and overlies the scatterer. Thus, their air-wave velocity features are on the surface of the glacier, not at depth. Their three-layer model for profile CD, therefore, is more appropriately a two-layer model, with a lower density layer, with more air and debris, overlying a denser layer, likely corresponding to the firn-ice transition. In addition, they carried out common mid-point (CMP) velocity profiles. While it is encouraging that they have made such an attempt, the results will be affected significantly by the surface and subsurface topography, truncated beds, unconformities, etc., because CMP profiles inherently assume flat-lying surface and subsurface boundaries. The CMP results, while useful, must therefore be treated with caution and assumed to be highly inaccurate and only be used as general guides to vertical velocity variations.

  14. Efecto del sobrepastoreo en un pastizal de altura. Cumbres de Humaya. Catamarca. Argentina

    Directory of Open Access Journals (Sweden)

    E.A. de la Orden

    2006-01-01

    Full Text Available El pastoreo continuo en los pastizales de altura de las Sierras de Humaya produce una profunda modificación en la estructura de la comunidad vegetal. El objetivo de este trabajo fue evaluar la magnitud del efecto del pastoreo por ganado doméstico sobre la acumulación de biomasa de la comunidad vegetal, y cómo afecta el pastoreo continuo el escurrimiento, la infiltración y la pérdida de suelo. Las tareas de campo se realizaron entre los meses de septiembre de 2000 y septiembre de 2002, en un área clausurada al ganado doméstico en noviembre de 1996, y en una adyacente. El pastoreo continuo no afectó a la cobertura vegetal, pero promovió una estructura de tipo césped, provocando un aumento de la escorrentía superficial y la exportación de sedimentos. La exclusión de pastoreo favoreció el establecimiento de especies de los géneros Festuca sp. y Stipa sp.

  15. ACERCA DE LA FLORA DE ANTOFAGASTA DE LA SIERRA, CATAMARCA, ARGENTINA. AMBIENTE Y PALEOAMBIENTE

    Directory of Open Access Journals (Sweden)

    M. Fernanda Rodríguez

    2013-01-01

    Full Text Available Se presenta una síntesis de los trabajos realizados sobre la identificación, anatomía y usos de especies vegetales, actuales y recuperadas en el marco de las investigaciones arqueobotánicas, llevadas a cabo en Antofagasta de la Sierra durante las campañas arqueológicas realizadas en los años 1994-2000. Se describen las transectas realizadas a partir de los sitios arqueológicos estudiados, las asociaciones vege- tales características y se presenta un listado de las especies vegetales halladas. Se describe el uso actual y se señala el nombre vernáculo para cada taxón. Luego, se presenta una descripción anatómica de tallo, raíz u hoja, dependiendo del caso, de cada uno de los taxones presentes en los sitios arqueológicos, identificados por medio de la comparación anatómica con material actual de referencia; se presentan las correspondientes fotomicrografías obtenidas con microscopio óptico y/o microscopio electrónico de barrido. Finalmente, se discute el uso, en la actualidad y en el pasado, de las especies recuperadas en los sitios arqueológicos del área de estudio, destacando aquellos aspectos que suponen cambio y continui- dad a través del tiempo.

  16. Mineralogía del Prospecto Bajo Agua Tapada, Catamarca, Argentina

    OpenAIRE

    Gimeno Torrente, Domingo; Carrazana, Ariana; Bruna Novillo, Julio; Fernández Turiel, José Luis

    2011-01-01

    El objeto de este trabajo es la definición por vez primera de las asociaciones minerales (menas productivas y paragénesis de alteración hidrotermal)del llamado Prospecto Bajo Agua Tapada, de cara a la realización de una primera valoración de su interés; este trabajo se ha realizado tanto mediante mapeo y muestreo superficial como tras el estudio (mineralógico y geoquímica)de unos 2800 m de sondeos realizados a testigo contínuo.

  17. Niveles de exposición de yacimientos del distrito minero Agua de Dionisio (YMAD, Catamarca

    Directory of Open Access Journals (Sweden)

    A. A. Gutiérrez

    2006-06-01

    Full Text Available Los yacimientos del distrito minero Agua de Dionisio quedaron al descubierto por el desplome y erosión del Complejo Volcánico Farallón Negro. El nivel de emplazamiento y procesos morfotectónicos posteriores son, entre otros, los factores que determinaron el nivel de exposición de cada yacimiento. De acuerdo al nivel de exposición, en las rocas de superficie están presentes elementos químicos representativos de la zonación vertical u horizontal del sistema hidrotermal. Se estudia el nivel de exposición de algunos yacimientos a partir del tratamiento geoestadístico de elementos químicos obtenidos de muestras de rocas de superficie. En el nivel de exposición del yacimiento epitermal Alto de la Blenda están presentes elementos característicos de la zona de sulfosales y otros de la zona de sulfuros del sistema epitermal. En el yacimiento epitermal Farallón Negro los elementos asociados se corresponden con la zona intermedia (sulfuros-sulfosales del sistema. En los yacimientos tipo pórfidos de cobre La Alumbrera y Las Pampitas los grupos de elementos determinados son representativos de la zona propilítica y de la zona sericítica-potásica de un sistema tipo pórfido de cobre. En el yacimiento El Durazno los grupos de elementos representan la zona de alteración sericítica-potásica y otros la zona propilítica de un sistema tipo pórfido de cobre. En la zona de Agua Tapada las muestras representan a prospectos epitermales y tipo pórfido de cobre; los grupos de elementos son representativos de la zona de sulfuros-sulfosales del sistema epitermal y no se logra diferenciar entre un sistema epitermal y otro tipo pórfido de cobre.

  18. Mega-deslizamientos de la pared sur del cerro Aconcagua y su relación con depósitos asignados a la glaciación pleistocena Mega-landslide in the southern wall of the Aconcagua and its relationship with deposits assigned to Pleistocene glaciations

    Directory of Open Access Journals (Sweden)

    Luis Fauqué

    2009-12-01

    Full Text Available Con motivo de la confección de un mapa de susceptibilidad a los procesos de remoción en masa que afectan a la localidad de Puente del Inca, se procedió a revisar la controvertida génesis del depósito Horcones. Se analizó la morfología del depósito y del paisaje circundante, la mineralogía y textura de sus materiales y finalmente se realizaron dataciones radimétricas. Sobre la base de estos estudios se concluye que el depósito de Horcones es el resultado de un flujo saturado derivado de una avalancha de rocas o mega-deslizamiento, originada por el colapso de una divisoria de aguas en la pared sur del cerro Aconcagua, durante tiempos tardioglaciales o postglaciales. Depósitos similares al de Horcones rellenan el valle del río Cuevas hacia el este y son cubiertos por otros, que también previamente fueron considerados como glaciarios (e.g. morena terminal del Drift Penitentes. El análisis de este material en las cercanías de la localidad de Penitentes, utilizando una metodología semejante, revela que corresponde a un flujo de gran envergadura proveniente de la quebrada Mario Ardito. De acuerdo a estas nuevas interpretaciones resulta clara la necesidad de realizar una exhaustiva revisión de la estratigrafía glaciaria en la zona. Surgen además nuevas ideas en cuanto a la génesis del monumento natural Puente del Inca. Finalmente, la comprensión de la evolución geomorfológica de la pared sur del cerro Aconcagua arroja luz sobre los surge del glaciar Horcones Inferior, revistiendo una gran importancia para la evaluación de los riesgos geológicos del Parque Provincial Aconcagua.During the preparation of a susceptibility map of mass wasting processes affecting Puente del Inca town, the controversial genesis of the Horcones deposit was reviewed and discussed. The surrounding landscape, the morphology of the deposit along with its mineralogical and textural features were analysed; finally several radiometric data were performed

  19. Caracterización petrográfica y geoquímica del batolito Cerro Aspero-Alpa Corral (32°34'-32°42' LS y 64°43'-64°52' LO, provincia de Córdoba, Argentina

    Directory of Open Access Journals (Sweden)

    Porta, G.

    1992-12-01

    Full Text Available The Cerro Aspero-Alpa Corral (CA-AC batholith is a 440 km2 granite body present in the Southern edge of the Eastern Pampean Ranges, Córdoba province, central Argentina. The intrusive body of probably paleozoic age shows both post-tectonic and epizonal character. Country rocks include Upper Precambrian-Lower Paleozoic metasedimentary rocks mainly represented by mica-schists, gneisses and migmatites, locally interrupted by minor amphibolite and marble outcrops.This paper deals with representative petrographic and geochemical data that characterize a 150 km2 central stripe between 32°34'-32°42'S and 64°43'-64°52'W.Three granitic facies have been distinguished based on their distinctive modal mineralogy and texture, and upon well known chemical parameters.A K-feldspar megacryst porphydic-type is the areally prevalent facies, but dykes of micro- leucogranites and biotite-phenocryst bearing granite are also well represented. They are all monzogranites of subalkaline and peraluminous chemistry. Their mineralogy shows variable proportions of QAP constituents and micas, with minor phases represented by Fe-Ti oxides, apatite (Ap, titanite (Tt, allanite (Aln.Microgranular enclaves, abundantly distributed in the porphydic facies, provide valuable information for a better understanding of parental magma evolution.The high-Ca content of the melt makes this body quite distinctive compared to its larger northern neighbour, the Achala batholith.Pegmatite and aplite bodies, as well as fluorite bearing breccias and quartz veins, barren or mineralized, are also present within the CA-AC batholith.El batolito Cerro Aspero-Alpa Corral (CA-AC es un cuerpo granítico que aflora en el extremo sur de las Sierras Pampeanas Orientales, en la provincia de Córdoba, República Argentina, cubriendo una superficie cercana a los 440 km2.Es un cuerpo intrusivo postcinemático de probable edad paleozoica. Las rocas encajantes son metamorfitas correspondientes al Prec

  20. ¿Un atajo al Paraíso?* Un análisis de la construcción epistemológica del modelo ‘bietápico’ de las reformas estructurales

    Directory of Open Access Journals (Sweden)

    Dante Avaro

    2004-12-01

    Full Text Available On the basis of the so called Washington Consensus, different “consensus” ensued, such as that of SanPablo, Santiago de Chile, and the cycle came to a close in 2001 with the lesser known Disensus of Washington. At different stages of the Washington Consensus, an analytical, ideographic and practical link was posed between first, second and third generation reforms. This paper tries to understand the relationship between first and second generation reforms under the heading of the two–stage model. Its main thesis is that there is an ideographic and logical coherence between the two generations of reform, although an insufficient epistemological construct prevails, which allows questioning the continuity between the two points in the two–stage model.

  1. Informe sobre el Proyecto Alfa Biblioteca de Babel: ¿Un atajo para la administración de bibliotecas universitarias? Biblioteca de Babel Alfa Project Report: A shortcut for the academic libraries management?

    Directory of Open Access Journals (Sweden)

    Liliana Laura Rega

    2006-12-01

    Full Text Available El Proyecto Alfa Biblioteca de Babel que reúne bibliotecas universitarias de América Latina y Europa comenzó en marzo de 2005 y prevé su conclusión en marzo de 2007. El presente trabajo intenta describir los objetivos y los resultados esperados, e informa las actividades realizadas por la Red Biblioteca de Babel. Finalmente se analizan las propuestas del proyecto en cuanto al rol de las bibliotecas universitarias, y su relación con la innovación en las prácticas pedagógicas.Biblioteca de Babel Alfa Project that assembles academic libraries from Latin America and Europe was approved on March, 2005 and its conclusion is foreseen on March, 2007. This article attempts to describe the aims and the expected results, and reports the activities of the Biblioteca de Babel Network. Finally it analizes the proposals of the project about the role of academic libraries and their relationship with innovations in pedagogical practices.

  2. El hábitat carpetano del cerro del Gollino

    OpenAIRE

    Perea Caveda, Alicia; Lourdes PRADOS TORREIRA; Santos Velasco, Juan Antonio

    1998-01-01

    [ES] Los resultados de las dos campairas de excavación en el yacimiento han permitido la identificación de un gran hábitat amurallado datable entre fines del siglo III a.c. y el primer tercio del siglo I a.c., que aporta datos significativos sobre el proceso de rornanización de la Carpetania.

  3. Parcels and Land Ownership, Published in 2008, Cerro Gordo County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Parcels and Land Ownership dataset, was produced all or in part from Published Reports/Deeds information as of 2008. This data set includes internal links to...

  4. Temperature distribution in the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Castillo B, F.; Bermejo M, F.J.; Domiguez A, B.; Esquer P, C.A.; Navarro O, F.J.

    1981-01-01

    A series of temperature and pressure logs and flow rate measurements was compiled for each of the geothermal wells drilled to different reservoir depths between October 1979 and December 1980. Based on the valuable information obtained, a series of graphs showing the thermal characteristics of the reservoir were prepared. These graphs clearly show the temperature distribution resulting from the movement of fluids from the deep regions toward the higher zones of the reservoir, thus establishing more reliable parameters for locating new wells with better production zones. Updated information based on data from new deep wells drilled in the geothermal field is presented here. This new information does not differ much from earlier estimates and theories. However, the influence of faulting and fracturing on the hydrothermal recharge of the geothermal reservoir is seen more clearly.

  5. Magnetotelluric studies at the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Goubau, W.M. (Lawrence Berkeley Lab., CA); Goldstein, N.E.; Clarke, J.

    1981-01-01

    During three years of magnetotelluric surveying, data were acquired at 26 sites distributed over 190 km/sup 2/ around the production area. A relatively well-defined strike of N27W +- 1.5/sup 0/ (magnetic) was established. The simple model shown suggests a lateral discontinuity in the vicinity of Nueva Leon.

  6. County and Parish Boundaries, Published in 2003, Cerro Gordo County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This County and Parish Boundaries dataset, was produced all or in part from Hardcopy Maps information as of 2003. Data by this publisher are often provided in State...

  7. Drilling rate for the Cerro Prieto stratigraphic sequence

    Energy Technology Data Exchange (ETDEWEB)

    Prian C, R.

    1981-01-01

    Drilling practice at the field has been modified in several ways as better information is being obtained. The stratigraphic sequence of the area is made up of three sedimentary rock units of deltaic origin having different densities. These units have been named non-consolidated, semi-consolidated, and consolidated rocks; the thermal reservoirs are located in the latter. To investigate how the drilling rates are affected by the three rock units, plots of drilling advance versus time were made for a large number of wells. A typical plot is shown and drilling rates are practically constant in three different zones; that is, the drilling rate has only two breaks or changes in slope.

  8. E-ELT project: geotechnical investigation at Cerro Armazones

    Science.gov (United States)

    Ghiretti, Paolo; Heinz, Volker; Pollak, Daniela; Lagos, Jose

    2012-09-01

    The design and construction of large telescopes include significant geotechnical challenges. In order to guarantee reliable and stable operations, a giant telescope like the European - Extremely Large Telescope (E-ELT) requires a foundation performance according to the level of accuracy of the other telescope's components. This paper describes the main geological and geotechnical activities conducted on site along with the studies completed in specialized geotechnical laboratories with the objective to achieve a thorough characterization of the ground conditions. This study shows that, the properties of the foundation materials are appropriate to guarantee a good performance of the E-ELT.

  9. Territorialidad y reproducción social: Los tinogasta en Belén, Catamarca, durante el siglo XVIII Territoriality and social reproduction: The tinogasta in Belen, Catamarca. 18th century

    Directory of Open Access Journals (Sweden)

    Federico Ignacio Vázquez

    2011-01-01

    Full Text Available Este trabajo se propone analizar las prácticas de territorialización desplegadas por los Tinogasta en Belén durante el siglo XVIII. Se analizaran los mecanismos jurídicos coloniales a partir de los cuales los Tinogasta buscaron "reterritorializar" su espacio, para recomponer sus condiciones de reproducción social. En este sentido, se observará cómo, frente a diversas prácticas de dominación, algunas poblaciones indígenas implementaron estrategias de resistencia, negociación y/o alianza para reinterpretar la realidad colonial y operar sobre ella. Así, lejos de ser meros espectadores pasivos de su dominio se transformaron en agentes de su reproducción social en un contexto de asimetría.This paper analyzes the practices of territorialization deployed by the Tinogasta in Belen through the 18th century. It will analyze how, through colonial legal mechanisms, the Tinogasta looked for "re-territorialize" their space in order to rebuild their conditions of social reproduction. We intend to observe how some Indian populations implemented multiple resistance, negotiation and/or alliance strategies against diverse domination practices in order to reinterpret -and operate on- the colonial reality. Then, far from being mere passive spectators of their dominance they became agents of their own social reproduction in an asymmetrical context.

  10. Macroindicadores cinemáticos en el Bloque Ambato, provincias de Tucumán y Catamarca Kinematic macroindicators in the Ambato Block, provinces of Tucumán and Catamarca

    Directory of Open Access Journals (Sweden)

    Adolfo Antonio Gutiérrez

    2008-03-01

    Full Text Available En el extremo oriental del antepaís andino (65°30'-66°15'O y 27°30'-28°30'S un conjunto de sierras (bloque Ambato se orientan en dirección noroeste evidenciando un desplazamiento hacia el este de aproximadamente 26,5 km que contrastan con la tendencia regional noreste de las sierras de Aconquija al norte y Ancasti al sur. Estas sierras pertenecen al sistema morfotectónico de Sierras Pampeanas. El conjunto de sierras que constituyen el bloque Ambato deben su morfoestructura actual a cizallamiento sinistral de rumbo noroeste que produjo procesos tectónicos extensivos y transpresivos en el Pleistoceno. Macroindicadores cinemáticos dan cuenta de estos procesos: fallas normales, cuencas intramontanas y valles, cuñas de deformación, fallas rotacionales, fallas inversas, cizallas Riedel y estructuras elípticas.At the eastern-most Andean foreland (65°30'-66°15'W y 27°30'-28°30'S the Ambato Block mountain shows a NW orientation which differs from the common NE regional strike, at this part of the Pampean Ranges. The present-day morphotectonics configuration of the Ambato Block is due to a Pleistocene synistral shear zone along the major north/south Andean faults. Kinematic macroindicators identified are: second order Riedel fractures, transpressive structure like deformation wedges and pull-apart basins, rotational faults, normal faults, inverse faults and eliptic structures.

  11. Zooarqueología de una unidad doméstica Formativa: El caso de Loma Alta (Catamarca, Argentina Zooarchaeology of a Formative domestic unit: The case of Loma Alta (Catamarca, Argentina

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    Andrés Darío Izeta

    2006-12-01

    Full Text Available El propósito de este trabajo es el de aportar datos e interpretaciones de la economía de una unidad doméstica de un sitio del Período Formativo del noroeste argentino (Loma Alta Núcleo E relacionada con el manejo de camélidos. El registro proporcionalmente menor del resto de los animales (aves, armadillos, roedores y ciervos hace casi imposible evaluar su significación económica sino es por comparación con la de los camélidos andinos. Por ello se tratarán en detalle los restos de camélidos con el fin de ofrecer algunas interpretaciones sobre la obtención, uso y manejo de estos animales entre los antiguos habitantes de este núcleo habitacional. Principalmente se estudió el conjunto de camélidos teniendo en cuenta las especies presentes, su proporción, así como las clases de edad representadas en esta muestra. A través del análisis del conjunto se pudo identificar la presencia de actividades pastoriles complementadas con prácticas de caza. En cuanto al uso específico de estos animales e independientemente de la edad se pudo establecer una estrategia general orientada hacia el consumo de unidades anatómicas de mayor valor económico.The aim of this paper is to present data and interpretations of the household economy of a Formative Period archaeological site from northwestern Argentina (Loma Alta Núcleo E based on the analysis of the camelid record. The occurrence of other taxa (birds, armadillos, rodents, and cervids is relatively poor, making their interpretation in economic terms very difficult without a comparison with camelid remains. Subsequently, camelid species presence and age classes (based on bone fusion stages are considered in order to evaluate the acquisition, use and management of those animals by the old inhabitants of this domestic unit. The study of the camelid assemblage allows us to interpret the presence of herding strategies complemented with hunting activities. Lastly, a general tendency towards the use of high return rate anatomical units was observed.

  12. Sucesiones lacustres postgondwánicas-preandinas en la región de Famatina (La Rioja y Catamarca Postgondwanic-preandean lacustrine successions in the Famatina Belt (La Rioja and Catamarca provinces

    Directory of Open Access Journals (Sweden)

    F.M. Dávila

    2005-03-01

    Full Text Available En el flanco oriental de la región central de Famatina al oeste de Angulos se describe una sucesión sedimentaria de ~180 m de espesor formada por niveles basales de silcretes grises, bancos de yeso blanquecinos y una sucesión de pelitas moradas y varicolores con intercalaciones de areniscas finas tabulares y bancos de dolomitas laminadas amarillentas. Esta localidad se conoce como La Yesera dado que, localmente, el banco de yeso engrosado tectónicamente alcanza 23 m de espesor. Esta sucesión suprayace en contacto neto a depósitos fluvio-eólicos del Pérmico reconocidos previamente en la región e infrayace en discordancia angular al Mioceno Inferior (Formación del Crestón. Las facies sedimentarias permiten interpretar que luego de una discontinuidad representada por el desarrollo de costras silicificadas se expandieron cuerpos lacustres hipersalinos, en condiciones de escaso relieve. La ubicación estratigráfica del intervalo estudiado junto a su comprobada extensión regional y los marcados contrastes litofaciales, de color y de la estratofábrica con los paquetes sedimentarios infra y suprayacentes permitiría considerar a este intervalo como una unidad litoestratigráfica independiente. Por tal razón, se propone denominarla Formación La Veteada, siendo su estratotipo la sección aflorante sobre el flanco oriental del anticlinal Los Colorados (La Yesera, próximo al cierre norte de dicha estructura. Análisis micropaleontológicos preliminares no han sido fértiles. No obstante, la correlación litoestratigráfica de este intervalo que ha sido también reconocido tanto en la vertiente occidental del Famatina como en las exposiciones de la región septentrional, junto a datos termocronológicos provenientes de la región circundante permitirían proponer una edad triásica a jurásica, aunque no puede descartarse una edad cretácica o hasta paleógena.On the eastern edge of the central Famatina Belt, west of the Angulos town, we describe a ~180-m thick sedimentary section compound of a basal grey silcrete covered by gypsum beds and a thick succession of purple mudstones interlayered by varicolored fine sandstones sheets and laminated yellowish dolomites. The study region is acknowledged as La Yesera, because of the recurrence of tectonicallythicken gypsum layers, which locally are ~23 m thick. The whole succession overlies the fluvio-eolian Permian and unconformably underlies Early Miocene synorogenic strata (Del Crestón Formation, both sequences already described in the literature. The sedimentary facies associations allow interpreting that after an important discontinuity evidenced by a siliceous duricrust, extent hypersaline lacustrine systems developed, which support low-relief settings. The stratigraphic position and regional distribution of these strata, together with the facies, color and stratofabric features would allow differentiating a new stratigraphic unit. Thus, we propose to name it the Veteada Formation, localizing its stratotype on the eastern limb of the Colorados anticline (La Yesera region, close to its northern plunging zone. Preliminary micropaleontological analyses on some of these beds have been unfortunately infertile. Yet, lithostratigraphic correlations across and along strike the Famatina Belt, plus indirect deductions coming from termochronologic data from Famatina and nearby regions, would suggest a Triassic or Jurassic age, although we cannot reject the Cretaceous or even Paleogene.

  13. AGRICULTURA Y POTENCIAL PRODUCTIVO EN EL VALLE DE AMBATO, CATAMARCA, ARGENTINA (SIGLOS VI A XI D.C / Agriculture and productive potential in the Ambato Valley, Catamarca, Argentina (VI-XI centuries AD

    Directory of Open Access Journals (Sweden)

    Germán Figueroa

    2009-12-01

    Full Text Available El control y acumulación de recursos económicos en el Valle de Ambato entre los siglos VI y XI d.C. ha sido considerado como un factor de suma importancia en el mantenimiento y reproducción de las diferencias sociales entre las personas. Se cree que el uso de sectores seleccionados del paisaje como áreas de producción agrícola se hallaba vinculado de manera funcional y organizacional con agregados residenciales o aldeas emplazadas en el fondo del valle. En dichos sectores, más precisamente sobre los faldeos de la sierra de la Graciana y del Ambato, se registró la presencia de infraestructura agrícola, tales como terrazas de cultivo, represas y canales. En este trabajo, se analizan los sistemas de cultivo y su potencial productivo en relación a los grupos humanos que habitaron el valle, para lo cual se lleva a cabo una caracterización del sistema hidro-agrícola y un análisis de su capacidad sustentadora en base a registros arqueológicos y observaciones etnográficas propias. Los resultados obtenidos permitirán discutir acerca de la posible existencia de un excedente económico, utilizado por un determinado sector de la población con el propósito de usufructuar los beneficios derivados del mismo.   Palabras clave: Valle de Ambato, Aguada, sistemas agrícolas, potencial productivo, excedente económico.   Abstract The control and accumulation of economic resources in the Ambato Valley between VI and XI centuries AD has been considered a key factor in the maintenance and reproduction of social differences between people. It is believed that the use of selected sectors of the landscape as agricultural production areas was functional and organizational associated with villages located in the valley bottom. In these sectors, and more precisely on the slopes of Graciana and Ambato mountain ranges, the presence of agricultural infrastructure was registered, such as farming terraces, dams and channels. In this paper, we analyze the farming systems and their productive potential in relation to the human groups that inhabited the valley. In order to accomplish these objectives we carry out a characterization of the hydro-agricultural system and an analysis of its carrying capacity based on archaeological records and our own ethnographic observations. The obtained results will allow discussing about possible existence of an economic surplus, used by a particular sector of the population with the purpose of usufruct benefits derived from it.   Keywords: Ambato Valle, Aguada, agricultural systems, productive potential, economic surplus.

  14. Niveles de exposición de yacimientos del distrito minero Agua de Dionisio (YMAD, Catamarca Exposures levels of the deposits of the Agua de Dionisio (YMAD mining district, Catamarca

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    A. A. Gutiérrez

    2006-06-01

    Full Text Available Los yacimientos del distrito minero Agua de Dionisio quedaron al descubierto por el desplome y erosión del Complejo Volcánico Farallón Negro. El nivel de emplazamiento y procesos morfotectónicos posteriores son, entre otros, los factores que determinaron el nivel de exposición de cada yacimiento. De acuerdo al nivel de exposición, en las rocas de superficie están presentes elementos químicos representativos de la zonación vertical u horizontal del sistema hidrotermal. Se estudia el nivel de exposición de algunos yacimientos a partir del tratamiento geoestadístico de elementos químicos obtenidos de muestras de rocas de superficie. En el nivel de exposición del yacimiento epitermal Alto de la Blenda están presentes elementos característicos de la zona de sulfosales y otros de la zona de sulfuros del sistema epitermal. En el yacimiento epitermal Farallón Negro los elementos asociados se corresponden con la zona intermedia (sulfuros-sulfosales del sistema. En los yacimientos tipo pórfidos de cobre La Alumbrera y Las Pampitas los grupos de elementos determinados son representativos de la zona propilítica y de la zona sericítica-potásica de un sistema tipo pórfido de cobre. En el yacimiento El Durazno los grupos de elementos representan la zona de alteración sericítica-potásica y otros la zona propilítica de un sistema tipo pórfido de cobre. En la zona de Agua Tapada las muestras representan a prospectos epitermales y tipo pórfido de cobre; los grupos de elementos son representativos de la zona de sulfuros-sulfosales del sistema epitermal y no se logra diferenciar entre un sistema epitermal y otro tipo pórfido de cobre.Deposits from the Agua de Dionisio mining district were uncovered by the collapse and erosion of the Farallón Negro Volcanic Complex. Site level and later morphotectonic processes are, among other, factors that determine the exposure level of each deposit. According to the exposure level, chemical elements being representative of the vertical or horizontal zoning of the hydrothermal system are present. The exposure levels of some deposits are studied from the geostatistical treatment of chemical elements obtained from surface rock samples. At the exposure level of the Alto de la Blenda epithermal deposit, characteristic elements from the sulfosalt zone, and others from the epithermal system sulphide zone are present. In the Farallón Negro epithermal deposit, the associated elements match with the system intermediate zone (sulphides-sulfosalts. In the La Alumbrera and Las Pampitas porphyry-type copper deposits, the groups of certain elements are representative of the propylitic and sericytic-potassic zones of a porphyry-type copper system. In the El Durazno deposit, some groups of elements represent the zone of sericytic-potassic alteration while others represent the propilytic zone of a porphyry-type copper system. In the Agua Tapada zone, the samples represent epithermal and porphyry-type copper prospects; the groups of elements are representative of the sulphide-sulphsalt zone of the epithermal system, but an epithermal and a porphyry-type copper system cannot be differentiated.

  15. Macroindicadores cinemáticos en el Bloque Ambato, provincias de Tucumán y Catamarca

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    Adolfo Antonio Gutiérrez

    2008-03-01

    Full Text Available En el extremo oriental del antepaís andino (65°30'-66°15'O y 27°30'-28°30'S un conjunto de sierras (bloque Ambato se orientan en dirección noroeste evidenciando un desplazamiento hacia el este de aproximadamente 26,5 km que contrastan con la tendencia regional noreste de las sierras de Aconquija al norte y Ancasti al sur. Estas sierras pertenecen al sistema morfotectónico de Sierras Pampeanas. El conjunto de sierras que constituyen el bloque Ambato deben su morfoestructura actual a cizallamiento sinistral de rumbo noroeste que produjo procesos tectónicos extensivos y transpresivos en el Pleistoceno. Macroindicadores cinemáticos dan cuenta de estos procesos: fallas normales, cuencas intramontanas y valles, cuñas de deformación, fallas rotacionales, fallas inversas, cizallas Riedel y estructuras elípticas.

  16. Violencia y tensión social en Rincón Chico 21 (Santa María, Catamarca

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    Mendonça, Osvaldo Juan

    2005-01-01

    Full Text Available El funeral y sus símbolos son formas en que las sociedades elaboran la muerte de sus miembros. La ceremonia puede presentar variaciones en su complejidad, pero sólo una porción de la misma termina formando parte del registro arqueológico. Esta circunstancia determina un número importante de recaudos al considerar la interpretación del registro funerario, particularmente las causas de muerte a partir de este registro. Una circunstancia especial lo constituye la muerte por causas violentas, ya que proporciona evidencias de índole tanto biológica como cultural. En este trabajo se describen y analizan críticamente los indicadores de muerte violenta en individuos de una cámara sepulcral (C-13 del cementerio de Rincón Chico 21. Un importante conjunto de puntas de proyectil impactando el interior de los cuerpos, la presencia de un esqueleto en condiciones de muy baja integridad, e inclusiones funerarias, permiten discutir e interpretar el conjunto en un escenario de violentas interacciones locales y regionales, de Contacto, y de resistencia territorial.

  17. Sarcophagidae (Diptera de importancia forense en la puna de Catamarca, Argentina: la ovoviviparidad como ventaja en condiciones de extrema aridez

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    Fernando H. ABALLAY

    2011-01-01

    Full Text Available A pesar de ser fauna necrófaga y de estar presentes en cadáveres humanos, los Sarcophagidae no suelen utilizarse en estudios forenses debido a la dificultad en su identificación y la poca información sobre su biología. En este trabajo, se identificaron las especies de Sarcophagidae asociadas a cadáveres y se estudió su relación con los estados de descomposición. Se analizaron las preferencias por los sustratos cadavéricos (cerdo y llama y las condiciones microambientales (sol y sombra en un ambiente de altura (3.600 msnm, durante la primavera. Se utilizaron dos cadáveres de cerdo dispuestos al sol y a la sombra y un cadáver de llama dispuesto al sol. Se colectaron 597 individuos pertenecientes a cinco especies de Sarcophagidae: M. antofagastensis Mulieri, Mariluis & Aballay (n=347, M. quimaliensis (Lopes (n=117, M. rusca (Hall (n=32, M. penai (Lopes (n=5 y M. aulacophyto Pape (n=96. Tanto M. antofagastensis, como M. quimaliensis fueron las únicas especies con colonización efectiva y representaron el 78% del total de adultos colectados. Microcerella antofagastensis fue la colonizadora primaria. Ambas especies respondieron de forma similar ante las condiciones microambientales y prefirieron el cadáver de cerdo. Se discute la importancia de M. antofagastensis y M. quimaliensis, como especies indicadoras y las posibles ventajas de la ovoviviparidad frente a otras especies ovíparas, en condiciones de extrema aridez.

  18. Petrología y estructura de la faja de deformación La Chilca, Catamarca

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    Mariano A. Larrovere

    2008-06-01

    Full Text Available Los estudios de campo, petrológicos y estructurales permitieron definir y caracterizar una zona de cizalla dúctil sobre el basamento metamórfico de las Sierras Pampeanas noroccidentales. La faja de deformación La Chilca se extiende en dirección nornoroeste por unos 24 kilómetros de largo y un ancho de 1 a 4 kilómetros sobre el límite austral de la sierra de Aconquija y su prolongación hacia el sur sobre la parte septentrional de la sierra de Ambato. Está compuesta por milonitas, protomilonitas y blastomilonitas que son el producto de la deformación dúctil que afectó al basamento metamórfico conformado originalmente por migmatitas y gneises. Las condiciones metamórficas durante la deformación alcanzaron la facies de esquistos verdes hasta la facies de anfibolita, con temperaturas de entre 350 a 500ºC. La foliación milonítica C predominante posee una orientación general N 330°/42° ENE, plano sobre el cual se desarrollan las lineaciones de estiramiento mineral con una orientación media de N 68°/42°. Determinamos para la esta faja de cizalla movimientos generales de carácter inverso, con desplazamientos del techo hacia el suroeste (N248°. Rasgos locales internos de carácter normal sugieren una mayor complejidad en la cinemática de deformación.

  19. Paisaje sociopolítico y beligerancia en el valle de Hualfín (Catamarca, Argentina.

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    Federico Wynveldt.

    2009-01-01

    Full Text Available In this article we propose an operative definition of landscape that includes not only its material aspects but also its capability to signify and direct social relationships. This concept is applied, focusing on the spatial dimension, to the study of three archaeological sites in the Argentinian Northwest, belonging to the Regional Development Period (1000-1480/Inka (1480-1535. Analyzing information related to the landscape, we interpret sociopolitical aspects concerning the inhabitants of the Hualfin Valley in a period characterized by confict and warfare.

  20. The use of NAA for chemical characterisation of clay sources within an archaeological ceramic study in the Chaschuil-Abaucan region (Tinogasta, Catamarca, Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Pla, R.R.; Moreno, M.A. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina). Tecnicas Analiticas Nucleares; Ratto, N.R. [Universidad de Buenos Aires (Argentina). Facultad de Filosofia y Letras. Seccion Arqueologia; Fuente, G. de la; Orgaz, M. [Universidad Nacional de Catamarca (Argentina). Escuela de Arqueologia

    2002-07-01

    Application of Neutron Activation Analysis (NAA) to provenience studies of archaeological ceramics involves the determination of clay sources used for their production. This work presents the study on raw materials and its relation to sherd results, on samples from Argentine southern Puna,using NAA. An hypothesis was stated that the Puna region of Chaschuil served as a corridor for the circulation of goods, energy and information, interconnecting large areas and relating to facilities at the bottom of the valley, especially at the Bolson de Fiambala. Potential raw material source locations were sampled both in Puna and valley, considering availability, plasticity, workability and textural fractions of the deposits. Factor analysis was used for evaluation of the results. The graphical representation of the first three factors showed a dense grouping of valley clays with Puna samples as outliers. Within the valley group, those clays from La Troya river appeared closely related to each other. XRD of these samples showed 100 % good quality clays for ceramic manufacture and high presence of clay fraction (17 - 45 % concentration values), with excellent properties regarding their plasticity and workability. The evaluation of a matrix composed of clay and sherd analytical results showed that sherds from valley area were manufactured with local raw materials that included the already sampled sources and others still to be located; that most of Puna sherds were manufactured with raw materials from the valley area, mainly La Troya and that Puna sources of raw materials were not used in the manufacture of those sherds sampled at Puna sites. (author)

  1. Ni utilitarios ni suntuarios. Los cinceles de metal del sitio Martínez 1, valle de Ambato, Catamarca, siglos VI al XI DC

    OpenAIRE

    Guillermina Espósito

    2006-01-01

    La clasificación dicotómica que le ha sido casi invariablemente otorgada a los objetos de metal, ha delimitado la caracterización de “lo metálico” a aquello prescripto por las categorías a través de las cuales justamente se lo clasificó, esto es, suntuario o utilitario. Pero ¿cómo distinguir el carácter utilitario o suntuario de un particular objeto metálico?, y en todo caso ¿cómo definir la practicidad o suntuosidad de algo?, ¿es relevante por sí sola la categorización de los obj...

  2. Londres y Catamarca: la articulación rural / urbano en una localidad del no argentino a fines del S. XX

    Directory of Open Access Journals (Sweden)

    Andrea Mastrángelo

    2000-06-01

    Full Text Available ¿Cómo organiza el espacio la expansión capitalista de fines del S. XX? A partir del análisis del caso de un emprendimiento minero en el noroeste argentino, este artículo realiza una revisión histórica de cómo se organiza, articuló históricamente y articula en la actualidad un centro urbano con unidades sociales mayores.How does capitalist expansion manage space at the end of XXth Century? Beginning with a case study on a mining mega enterprise in argentinian NW, this article makes a historical revision on how did a little community survive and how did it managed and articulated with greater social units.

  3. Patrimonio geológico en una región de la Sierra de Aconquija, Provincias de Tucumán y Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    Gloria Patricia Ibáñez Palacios

    2012-01-01

    Full Text Available Los accesos al Parque Nacional Campo de Los Alisos (Sierra de Aconquija poseen una gran geodiversidad, que repercute en un rico y variado Patrimonio geológico con múltiples recursos turísticos y paisajísticos aún no aprovechados de manera sustentable. En este trabajo se presenta un inventario preliminar de los lugares de interés geológico (LIG relacionados con las criogeoformas cuaternarias en la región, con el objeto de divulgar el Patrimonio geológico y la preservación de los geositios en la región, y ofrecer estos conocimientos a los especialistas en turismo para que se generen los georecursos y geoproductos necesarios para la actividad turística. Durante el trabajo de campo se identificaron numerosos lugares de interés geológico.

  4. Distribución de las alteraciones y mineralizaciones enla sección central del yacimiento Agua Rica (27º22'S-66º16'O, Catamarca

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    Marta Franchini

    2009-06-01

    Full Text Available Agua Rica es un yacimiento deCu (Mo-Au de clase mundial en el cual las alteraciones-mineralizaciones tipopórfido y epitermal de alta sulfuración que normalmente distan 1 km en sentidovertical, están localizadas en el mismo nivel de erosión. En el sectoroccidental de la sección analizada, el pórfido Seca Norte preserva relictos dealteración potásica del estadio de alteración temprano de alta temperatura conla mineralización de Cu (Mo, Au encapsulada en un halo fílico donde lacalcopirita, la pirita y la bornita formadas en condiciones de sulfuración bajaa intermedia, han sido reconstituidas en covellita y pirita bajo condiciones dealta sulfuración. La paragénesis de alta temperatura de la alteración arcillosaavanzada (andalucita y pirofilita ± diasporo, formada a partir de lacondensación del vapor magmático, se preserva en las raíces del halo dealteración arcillosa avanzada y en los clastos de las brechas hidrotermalesreemplazando a la alteración fílica. Los clastos de sílice residual con huecosen los niveles más superficiales de la brecha central, sugieren que atemperaturas más bajas los fluidos alcanzaron pH muy bajos. El brechamientosubsecuente, probablemente acaecido durante la energía mecánica liberada delemplazamiento de magma en niveles superficiales, y los fluidos hidrotermalesgenerados precipitaron una paragénesis de temperatura intermedia (alunita +diásporo + zunyita con abundante covellita + enargita + pirita ± kuramita yazufre nativo que cementaron los clastos en las partes más profundas. La presenciade esfalerita, emplectita, colucita, sulfuro de Pb y Bi y azufre nativo con oroy plata en los niveles superiores de las brechas, indica flujos tardíos defluidos hidrotermales con oro, probablemente con temperaturas más bajas peroaún con alta actividad del azufre, según la ausencia de hierro en lacomposición de la esfalerita.

  5. "LOS TECHOS DEL VECINO": ANÁLISIS ANTRACOLÓGICO DE RESTOS DE CONSTRUCCIÓN CARBONIZADOS DE LOS SITIOS "IGLESIA DE LOS INDIOS" Y "PIEDRAS BLANCAS" (CATAMARCA

    Directory of Open Access Journals (Sweden)

    María B. Marconetto

    2008-01-01

    Full Text Available El registro arqueológico del Valle de Ambato en el Noroeste argentino presenta la particularidad de preservar las maderas empleadas en la construcción de los asentamientos, debido a incendios ocurridos en la zona hacia el siglo XI d.C. Esta peculiaridad ha permitido recuperar hasta el momento abundante material. Se realizó la identificación taxonómica de muestras correspondientes a 105 troncos utilizados como postes y vigas en la construcción de los sitios "Iglesia de los Indios" y "Piedras Blancas". Los análisis antracológicos presentaron resultados sensiblemente diferentes, habiéndose empleado para la Iglesia de los Indios materias primas alóctonas al valle, contrariamente a lo que ocurre en el sitio Piedras Blancas. Sobre esta base se discuten las correspondencias entre ambos sitios en torno a la selección, usos y significados de los distintos recursos forestales.

  6. Stock monzogranítico El Chorro (Sierra de Ancasti, Catamarca: un ejemplo de magmatismo tipo S con granate ígneo

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    Juan A Dahlquist

    2011-06-01

    Full Text Available Las rocas graníticas ordovícicas de la sierra de Ancasti representan uno de los afloramientos más orientales del cinturón orogénico famatiniano de Sierras Pampeanas. Se describe un pequeño stock granítico (denominado El Chorro cuyo rasgo distintivo es la presencia de granate. Aunque el granate es un mineral accesorio poco común en rocas ígneas, su presencia es petrológicamente significativa. El Chorro es un monzogranito tipo S que contiene una inusual cantidad de granate magmático (2,8 % modal. Estudios combinados de petrología, química mineral y de geoquímica de roca total sugieren que se trata de un magma peraluminoso generado por la fusión parcial de rocas metasedimentarias, con la subsecuente formación de granate durante la cristalización. Los estudios realizados muestran que el granate cristalizó en equilibrio con otras fases minerales como biotita y muscovita. Cálculos geotermobarométricos revelan una temperatura de cristalización de 710-716 ºC y una presión de 3,8 + 0,8 kbar, indicando que el magma fue emplazado en la corteza media (~ 14 km con temperaturas de cristalización magmáticas medias a bajas.

  7. Patrimonio geológico en una región de la Sierra de Aconquija, Provincias de Tucumán y Catamarca, Argentina

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    Gloria Patricia Ibáñez Palacios

    2012-01-01

    Full Text Available Access to Campo de los Alisos National Park, Sierra de Aconquija, has a varied geological heritage, offering numerous tourist attractions, natural resources and landscapes not yet used in a sustainable way. We present a preliminary inventory of geological interest sites related to Quaternary cryoforms in the region in order to link this geological heritage with educational aims and economic use. The aim is to increase consciousness about the value of this natural area and the same time the wish to enhance the environmental protection of the geological interest sites, and offer this knowledge to specialists in tourism to generate the georesources and geoproducts necessary for tourism activity. Large number of geotopes were identified during the field work.

  8. Control estructural sobre el plutón Los Ratones y la mineralización de uranio en la sierra de Fiambalá, Sierras Pampeanas, Catamarca

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    Fernando Hongn

    2010-12-01

    Full Text Available El Granito Los Ratones, de edad carbonífera, está compuesto por dos facies principales: porfírica y equigranular. La mineralización de uranio alojada en la caja metamórfica sobre el borde NO del plutón se interpreta asociada a un greisen abierto rico en flúor vinculado con las facies equigranular. La cartografía detallada de la roca de caja del plutón, de parte de los bordes del intrusivo y de las manifestaciones uraníferas muestra un marcado control estructural sobre el emplazamiento del plutón, particularmente de la facies porfírica, y sobre la circulación de los fluidos mineralizantes. Cuatro juegos de fracturas participan de este control. Los dos principales de rumbo N y NE coinciden nítidamente con los bordes oeste y noroeste de la facies porfírica y con las expresiones más notables de la mineralización de uranio. El tercer juego corresponde a fracturas de rumbo E-O que son secundarias respecto a las anteriores considerando su frecuencia y longitud, al igual que el cuarto de rumbo NO. Los buzamientos de los juegos de fracturas N y NE son próximos a la vertical, orientación corroborada por estudios geofísicos en la zona dominada por las fracturas NE. Además de los rasgos mencionados, los diques básicos y ácidos que acompañan al plutón siguen preferentemente estas orientaciones. Las estructuras que controlan el magmatismo y la mineralización estarían vinculadas con un sistema de fallas meridianas con movimiento horizontal derecho principal y normal subordinado que parcialmente reactivaron heterogeneidades del basamento metamórfico, básicamente la foliación principal. Flexiones y quiebres a lo largo de estas estructuras generaron zonas dilatantes en las que se concentraron el magmatismo y la mineralización.

  9. Carbon isotope geochemistry of hydrocarbons in the Cerro Prieto geothermal field, Baja California Norte, Mexico

    Science.gov (United States)

    Des Marais, D. J.; Stallard, M. L.; Nehring, N. L.; Truesdell, A. H.

    1988-01-01

    Hydrocarbon abundances and stable-isotopic compositions were measured in wells M5, M26, M35 and M102, which represent a range of depths (1270-2000 m) and temperatures (275-330 degrees C) in the field. In order to simulate the production of the geothermal hydrocarbons, gases were collected from the pyrolysis of lignite in the laboratory. This lignite was obtained from a well which sampled rock strata which are identical to those occurring in the field, but which have experienced much lower subsurface temperatures. In both the well and the laboratory observations, high-temperature environments favored higher relative concentrations of methane, ethane and benzene and generally higher delta 13C-values in the individual hydrocarbons. The best correlation between the laboratory and well data is obtained when laboratory-produced gases from experiments conducted at lower (400 degrees C) and higher (600 degrees C) temperatures are mixed. This improved correlation suggests that the wells are sampling hydrocarbons produced from a spectrum of depths and temperatures in the sediments.

  10. The Dancing Sky: 6 years of night sky observations at Cerro Paranal

    CERN Document Server

    Patat, F

    2008-01-01

    The present work provides the results of the first six years of operation of the systematic night-sky monitoring at ESO-Paranal (Chile). The UBVRI night-sky brightness was estimated on about 10,000 VLT-FORS1 archival images, obtained on more than 650 separate nights, distributed over 6 years and covering the descent from maximum to minimum of sunspot cycle n.23. Additionally, a set of about 1,000 low resolution, optical night-sky spectra have been extracted and analyzed. The unprecedented database discussed in this paper has led to the detection of a clear seasonal variation of the broad band night sky brightness in the VRI passbands, similar to the well known semi-annual oscillation of the NaI D doublet. The spectroscopic data demonstrate that this seasonality is common to all spectral features, with the remarkable exception of the OH rotational-vibrational bands. A clear dependency on the solar activity is detected in all passbands and it is particularly pronounced in the U band, where the sky brightness de...

  11. El hábitat carpetano del cerro del Gollino (Corral de Almaquer, Toledo)

    OpenAIRE

    Santos Velasco, Juan Antonio; Perea Caveda, Alicia; Lourdes PRADOS TORREIRA

    1998-01-01

    Los resultados de las dos campañas de excavación en el yacimiento han permitido la identificación de un gran hábitat amurallado datable entre fines del siglo III a. C. y el primer tercio del siglo I a. C., que aporta datos significativos sobre el proceso de romanización de la Carpetania. Les fouilles qui ont eu lieu dans cet oppidum permettent dater le gisement entre la fin du IIIème et le premier tiers du Ier siècle av.C., et offrent des éléments pour comprendre le procès d'aculturation d...

  12. VizieR Online Data Catalog: Cerro Armazones spectroscopy of F dwarfs (Pribulla+, 2014)

    Science.gov (United States)

    Pribulla, T.; Sebastian, D.; Ammler-von Eiff, M.; Stahl, O.; Berndt, A.; Chini, R.; Hoffmeister, V.; Mugrauer, M.; Neuhauser, R.; Vanko, M.

    2015-04-01

    Optical spectroscopy at the OCA was secured using the BESO spectrograph fibre-fed from the focus of the 1.5m Hexapod telescope (see Fuhrmann et al. 2011). 409 spectra of 187 dwarfs were obtained between 2009 April 10 and 2010 March 29. Exposure times ranged between 300 and 1800s. (2 data files).

  13. Cerro Xalapaxco: An Unusual Tuff Cone with Multiple Explosion Craters, in Central Mexico (Puebla)

    Science.gov (United States)

    Abrams, M. J.; Siebe, C.

    1994-01-01

    The Xalapaxco tuff cone is located on the northeast flank of La Malinche stratovolcano in central Mexico. An unusually large number (10) of explosion craters, concentrated on the central and on the uphill side of the cone, expose alternating beds of stratified surge deposits and massive fall deposits.

  14. Two-dimensional inversion of resistivity monitoring data from the Cerro Prieto geothermal field

    Science.gov (United States)

    Goldstein, N. E.; Sasaki, Y.; Wilt, M. J.

    1985-03-01

    Two dimensional iterative, least-squares inversions were performed on dc resistivity data obtained over the geothermal field at five successive times during the 1979-1983 period. The solutions gave the percent change in resistivity within each of 47 rectangular blocks representing the reservoir and recharge regions. The changes are consistent with hydrogeologic and recharge models, on the basis of geophysical well logs, well cuttings, well production, geochemical and reservoir engineering data. The solutions support the model of a reservoir that is recharged mainly by cooler, less saline water, causing changes in both pore fluid resistivity and the extent of boiling near the wells. There may be a component of high-temperature recharge from below and to the east, but flow may be impeded by a two-phase zone. Notwithstanding the various sources of error and uncertainty in the data acquisition and 2-D inversions, repetitive, high precision dc resistivity monitoring seems to be a useful method for assessing reservoir conditions when used in conjunction with production and reservoir engineering data and analysis.

  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CERRO GORDO COUNTY, IOWA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  16. Rehabilitación Unión Obrera: cerro Cordillera

    OpenAIRE

    Araya, Raúl; Castillo Couve, Maria Jose; Prado,Francisco

    2009-01-01

    La recuperación del edificio donado en 1898 por Juana Ross de Edwards, es la primera experiencia de rehabilitación de vivienda social con carácter patrimonial. Se destaca en la operación la decisión de los habitantes de permanecer viviendo en el inmueble, tras mejorar sus condiciones de habitabilidad y de equipamiento.

  17. Analysis of exploratory wells in the Cerro Prieto Field and the Mexicali Valley

    Energy Technology Data Exchange (ETDEWEB)

    Cobo R., J.M.; Bermejo M., F.J.

    1982-08-10

    Agricultural development in the Mexicali Valley and in the high cost of electric power required to operate the irrigation wells in the Valley prompted the Mexican government to investigate the possibility of taking advantage of thermal manifestations in the area located 28 km southeast of the city of Mexicali to generate electric power and thereby partially decrease the flight of foreign exchange. In 1958, a geologic study of the southern and southeastern zone of Mexicali was conducted to identify the possibilities of tapping geothermal resources. The purpose of this study was to gain knowledge of the geologic conditions in this area and, if possible, to establish the location of exploratory and production wells and, on the basis of the results of the former, examine the geologic history in order to gain knowledge and understanding of the structural control of the steam. On the basis of this study, it was recommended that 3 exploratory wells should be drilled in order to locate weak zones that would easily allow for steam flow.

  18. Proceedings: third symposium on the Cerro Prieto geothermal field, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    These proceedings include both English and Spanish versions of each paper presented at the symposium. Illustrations and tables, which have been placed between the two versions, include captions in both languages. Forty-one papers are included. Five papers were indexed for EDB previously. Separate abstracts were prepared for thirty-three papers and three were listed by title.

  19. Highlighting the 'Multiple' in MSPs: The Case of Cerro Chapelco, Patagonia, Argentia

    NARCIS (Netherlands)

    Moreyra, A.; Wegerich, K.

    2006-01-01

    Mainstream opinions put forward the idea that changes in water policies should be moving toward Integrated Water Resources Management at the level of the river basin (or watersheds). For its implementation, participation by river basin organizations (river basin authorities, river basin committees,

  20. Carbon isotope geochemistry of hydrocarbons in the Cerro Prieto geothermal field, Baja California Norte, Mexico.

    Science.gov (United States)

    Des Marais, D J; Stallard, M L; Nehring, N L; Truesdell, A H

    1988-01-01

    Hydrocarbon abundances and stable-isotopic compositions were measured in wells M5, M26, M35 and M102, which represent a range of depths (1270-2000 m) and temperatures (275-330 degrees C) in the field. In order to simulate the production of the geothermal hydrocarbons, gases were collected from the pyrolysis of lignite in the laboratory. This lignite was obtained from a well which sampled rock strata which are identical to those occurring in the field, but which have experienced much lower subsurface temperatures. In both the well and the laboratory observations, high-temperature environments favored higher relative concentrations of methane, ethane and benzene and generally higher delta 13C-values in the individual hydrocarbons. The best correlation between the laboratory and well data is obtained when laboratory-produced gases from experiments conducted at lower (400 degrees C) and higher (600 degrees C) temperatures are mixed. This improved correlation suggests that the wells are sampling hydrocarbons produced from a spectrum of depths and temperatures in the sediments.

  1. Cerro Prieto Geothermal Field, Proceedings of the Symposium, 1st, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Barbier, E. (ed.)

    1979-01-01

    This conference is published in two volumes and contains 35 papers, 31 of which are abstracted separately. The subject matter is primarily concerned with the understanding of geology, hydrogeology, geophysics, reservoir engineering, geochemistry and electric power generation associated with the procurement of geothermal energy.

  2. Control estructural sobre el plutón Los Ratones y la mineralización de uranio en la sierra de Fiambalá, Sierras Pampeanas, Catamarca Structural control on the Los Ratones pluton and the uranium mineralization at the Fiambalá range, Sierras Pampeanas, Catamarca

    Directory of Open Access Journals (Sweden)

    Fernando Hongn

    2010-12-01

    Full Text Available El Granito Los Ratones, de edad carbonífera, está compuesto por dos facies principales: porfírica y equigranular. La mineralización de uranio alojada en la caja metamórfica sobre el borde NO del plutón se interpreta asociada a un greisen abierto rico en flúor vinculado con las facies equigranular. La cartografía detallada de la roca de caja del plutón, de parte de los bordes del intrusivo y de las manifestaciones uraníferas muestra un marcado control estructural sobre el emplazamiento del plutón, particularmente de la facies porfírica, y sobre la circulación de los fluidos mineralizantes. Cuatro juegos de fracturas participan de este control. Los dos principales de rumbo N y NE coinciden nítidamente con los bordes oeste y noroeste de la facies porfírica y con las expresiones más notables de la mineralización de uranio. El tercer juego corresponde a fracturas de rumbo E-O que son secundarias respecto a las anteriores considerando su frecuencia y longitud, al igual que el cuarto de rumbo NO. Los buzamientos de los juegos de fracturas N y NE son próximos a la vertical, orientación corroborada por estudios geofísicos en la zona dominada por las fracturas NE. Además de los rasgos mencionados, los diques básicos y ácidos que acompañan al plutón siguen preferentemente estas orientaciones. Las estructuras que controlan el magmatismo y la mineralización estarían vinculadas con un sistema de fallas meridianas con movimiento horizontal derecho principal y normal subordinado que parcialmente reactivaron heterogeneidades del basamento metamórfico, básicamente la foliación principal. Flexiones y quiebres a lo largo de estas estructuras generaron zonas dilatantes en las que se concentraron el magmatismo y la mineralización.The Carboniferous Los Ratones pluton is composed by two main facies: equigranular and porphyric. The uranium mineralization hosted by the metamorphic rock on the NW border of the pluton is related to a fluor- rich greisen related to the equigranular facies. The detailed mapping of the pluton host rock and the uranium mineralization shows a well-defined structural control on both the granite emplacement, particularly on the porphyric facies, and on the migration of the mineralized fluids. Four sets of fractures participate on this control. The two main with N and NE trends coincide clearly with the west and northwest border of the pluton as well as with the high-grade uranium manifestations. The third and fourth ones respectively corresponds to E-W and NW striking fractures, which are less developed in relation to the main fractures considering their frequency and size. Fractures of the four sets are high dipping close to vertical, attitude corroborated by geophysical studies in the area where the NE fractures are the best developed. In addition to the mentioned features, granite-related acidic and basic dikes follow mainly these orientations. The fracture sets seem to be related to a high-east dipping meridian fault system with right horizontal main movement component and subordinate normal displacement. These faults partially reactivated heterogeneities of the metamorphic rocks, mainly the dominant foliation. Changes on the strike of these fractures formed dilatant zones where magmatism and related mineralization were concentrated.

  3. Sarcophagidae (Diptera de importancia forense en la puna de Catamarca, Argentina: a ovoviviparidad como ventaja en condiciones de extrema aridez Sarcophagidae (Diptera of forensic importance at a high altitude desert in Catamarca, Argentina: ovoviviparity as an advantage under extreme arid conditions

    Directory of Open Access Journals (Sweden)

    Fernando H. Aballay

    2011-12-01

    Full Text Available A pesar de ser fauna necrófaga y de estar presentes en cadáveres humanos, los Sarcophagidae no suelen utilizarse en estudios forenses debido a la dificultad en su identificación y la poca información sobre su biología. En este trabajo, se identificaron las especies de Sarcophagidae asociadas a cadáveres y se estudió su relación con los estados de descomposición. Se analizaron las preferencias por los sustratos cadavéricos (cerdo y llama y las condiciones microambientales (sol y sombra en un ambiente de altura (3.600 msnm, durante la primavera. Se utilizaron dos cadáveres de cerdo dispuestos al sol y a la sombra y un cadáver de llama dispuesto al sol. Se colectaron 597 individuos pertenecientes a cinco especies de Sarcophagidae: M. antofagastensis Mulieri, Mariluis & Aballay (n=347, M. quimaliensis (Lopes (n=117, M. rusca (Hall (n=32, M. penai (Lopes (n=5 y M. aulacophyto Pape (n=96. Tanto M. antofagastensis, como M. quimaliensis fueron las únicas especies con colonización efectiva y representaron el 78% del total de adultos colectados. Microcerella antofagastensis fue la colonizadora primaria. Ambas especies respondieron de forma similar ante las condiciones microambientales y prefirieron el cadáver de cerdo. Se discute la importancia de M. antofagastensis y M. quimaliensis, como especies indicadoras y las posibles ventajas de la ovoviviparidad frente a otras especies ovíparas, en condiciones de extrema aridez.Despite their prevalence in human corpses during decomposition, Sarcophagidae are not frequently used in forensic studies due to the difficulty in their identification and to the lack of information on their biology. In this paper, we identified the species of Sarcophagidae associated to corpses and studied their relationship to decomposition stages. We analyzed preferences for different cadaveric substrates (pig and lama and microenvironmental conditions (shade, sun at a site located at 3600 m.a.s.l. during the spring. Two pig carcasses, one located in the shade and the other in the sun, and a third carcass of a lama located in the sun, were used. We collected 597 individuals belonging to five Sarcophagidae species: Microcerella antofagastensis Mulieri, Mariluis & Aballay (n=347, M. quimaliensis (Lopes (n=117, M. rusca (Hall (n=32, M. penai (Lopes (n=5 and M. aulacophyto Pape (n=96. Both M. antofagastensis and M. quimaliensis were the effective colonizers and represented 78% of the total adults collected. Microcerella antofagastensis was the primary colonizer. Both species had a similar response against microenvironmental conditions and both preferred the pig carcass. We discuss the importance of these two species as forensic indicators and the advantages of ovoviviparity against other oviparous species under extreme arid conditions.

  4. Los depósitos de bentonita de Barda Negra y cerro Bandera, departamento Zapala, provincia del Neuquén, Argentina Bentonite deposits of Barda Negra and Cerro Bandera, Zapala Department, Neuquén Province, Argentina

    Directory of Open Access Journals (Sweden)

    A. Impiccini

    2002-09-01

    Full Text Available Las bentonitas de la región nordpatagónica pueden ser agrupadas en dos distritos mineralogenéticos caracterizados desde el punto de vista geológico, geográfico y estratigráfico. En este trabajo se considera a las bentonitas terciarias localizadas en la región occidental, en el departamento Zapala, provincia del Neuquén. Los depósitos consisten en estratos lenticulares, subhorizontales, de 2 a 15 metros de espesor, la mayoría de ellos aflorantes. Están incluidos en la Formación Collón Curá, una secuencia miocena continental donde alternan tobas y areniscas. Los cuerpos de arcilla son productos de alteración de materiales piroclásticos vítreos en ambientes húmedos confinados, tales como cuerpos de agua someros. Los análisis por difracción de rayos X muestran que prevalece una esmectita dioctaédrica - montmorillonita - como único mineral arcilloso en la mayoría de los depósitos. Los minerales accesorios son cuarzo, feldespato, plagioclasa y cristobalita (ópalo-CT, y en menor proporción, ceolitas y yeso. El Na+ es el ión intercambiable dominante, junto con Ca++, Mg++ y K+. El contenido en Fe2O3 es muy alto. Estas bentonitas son buenos agentes ligantes en arenas de moldeo para fundición, pero sus propiedades reológicas y el test de filtrado no cumplen exactamente con las normas API para lodos de perforación de petróleo.Bentonites from the North Patagonia region can be grouped in two mineralogenic districts distinguishable on geological, geographical, and stratigraphical criteria. In this paper, we consider the Tertiary bentonites located in the western region, Zapala Department, Neuquén Province. The deposits occur in sub-horizontal lenticular beds, 2 to 15 m in thickness, most of which crop out at the surface. They lie within the Collón Curá Formation, a Miocene continental sequence of alternating tuffs and sandstones. The clay bodies are alteration products of pyroclastic glassy materials in confined wet environments, like shallow-water bodies. XRD analysis shows that a dioctahedral smectite -montmorillonite- prevails and is the only clay mineral occurring in the majority of the deposits. Accessory minerals are quartz, feldspar, plagioclase and cristobalite (opal-CT, with lesser amounts of zeolites and gypsum. Na+ is the dominant exchangeable ion, along with Ca++, Mg++ and K+. The Fe2O3 content is very high. The bentonites are good bonding agents in foundry molding sands, but their rheological and leak test properties do not match exactly with API regulations for oil-drilling muds.

  5. APORTES PALEOBOTÁNICOS EN LA RECONSTRUCCIÓN DE PALEODIETAS. ANÁLISIS DE COPROLITOS DEL CERRO CASA DE PIEDRA, SANTA CRUZ/Palaeobotany contributions in palaeodiets reconstruction. Coprolites analysis of Cerro Casa de Piedra, Santa Cruz.

    Directory of Open Access Journals (Sweden)

    Ana Cecilia Martínez Tosto

    2012-11-01

    Full Text Available Los coprolitos son heces fósiles deshidratadas o mineralizadas que contienen inclusiones orgánicas e inorgánicas. El estudio de las inclusiones de origen vegetal de los coprolitos permite conocer los ítems vegetales consumidos por los organismos e inferir la estacionalidad en el uso del sitio. El objetivo de este trabajo es estudiar el contenido de polen y de microrrestos vegetales de un coprolito humano del sitio CCP7 relacionado a una capa arqueológica fechada en 8920±200 C14 (UGA 7383 años AP. El sitio CCP7 está ubicado en la provincia de Santa Cruz (Argentina en el ecotono bosque-estepa. Se realizaron los análisis polínicos y microhistológicos de los restos vegetales del coprolito. Se identificaron 13 tipos polínicos, tres de ellos pertenecientes a la vegetación del bosque y el resto a la estepa. Mediante el análisis microhistológico se identificaron las especies Azorella monanthos, Empetrum rubrum y Gaultheria mucronata. El análisis simultáneo de la información extraída de los datos palinológicos y de los microhistológicos mostró coincidencias parciales entre el contenido de polen y de restos vegetales, permitiendo reconstruir la porción vegetal de la paleodieta e inferir la época del año en que el hombre que dio origen al coprolito estuvo ocupando el sitio CCP7.   Abstract Coprolites are dehydrated or mineralized fossil feces containing organic and inorganic inclusions. The study of plant inclusions of coprolites allows knowing the vegetable items consumed by organisms and inferring the seasonality in the use of the site. This work aims at studying pollen and plant remains from a human coprolite in the CCP7 site related to an archaeological layer dated from around 8920±200 14C (UGA 7383 years BP. CCP7 is located in the province of Santa Cruz (Argentina within the forest-steppe ecotone. Pollen and microhistological analyses of coprolite plant remains were conducted. Thirteen pollen types were identified: three from forest vegetation and the rest from the steppe. Azorella monanthos, Empetrum rubrum and Gaultheria mucronata were identified by means of microhistological analysis. Simultaneous microhistological and palynological data analysis showed partial matches between the content of pollen and plant remains, which helped to rebuild the palaeodiet plant portion and infer the time of year that the person who produced the coprolite was occupying the CCP7 site.

  6. Note on the diet of Ameiva edracantha (Squamata, Teiidae in Cerros de Amotape National Park, Tumbes, Peru

    Directory of Open Access Journals (Sweden)

    Juan C. Jordán

    2011-08-01

    Full Text Available The diet of Ameiva edracantha Bocourt 1874, a terrestrial diurnal teiid lizard distributed in northwestern Peru and southwestern Ecuador is described for the first time. Stomach contents of fifteen individuals collected from quebrada La Angostura were analyzed. Lepidopteran larvae, coleopterans, orthopterans and spiders were the dominant preys in the lizard’s diet. Snout-vent length and head length, width and height were not correlated to prey length, width and volume. Other parameters such as profitability and prey target selection could be involved in prey selection by A. edracantha.

  7. Cerro Bombero: registro de Hippidion saldiasi Roth, 1899 (Equidae, Perissodactyla en el Holoceno temprano de Patagonia (Santa Cruz, Argentina

    Directory of Open Access Journals (Sweden)

    Alberdi, M. T.

    2008-06-01

    Full Text Available A new record of Hippidion saldiasi with new radiocarbon data referred to early Holocene (8,850 ± 80 year C-14 B.P of Patagonia is reported. Both its peculiar geographic location in a scarcely prospected zone and its radiocarbon age, provide new elements to discuss the previous hypotheses about the extinction of the horses and its relations with the human beings that inhabited the different environments of South America.Presentamos un nuevo registro de Hippidion saldiasi con datación radiocarbónica directa correspondiente al Holoceno temprano de Patagonia (8.850 ± 80 años C-14 AP. Su particular ubicación temporal y geográfica en una zona poco estudiada hasta ahora y su registro reciente, aportan nuevos elementos para discutir las hipótesis previas sobre la extinción de los caballos y su relación con los grupos humanos que colonizaron los diferentes ambientes de América del Sur.

  8. GIS-Based Detection of Gullies in Terrestrial LiDAR Data of the Cerro Llamoca Peatland (Peru

    Directory of Open Access Journals (Sweden)

    Markus Forbriger

    2013-11-01

    Full Text Available Cushion peatlands are typical features of the high altitude Andes in South America. Due to the adaptation to difficult environmental conditions, they are very fragile ecosystems and therefore vulnerable to environmental and climate changes. Peatland erosion has severe effects on their ecological functions, such as water storage capacity. Thus, erosion monitoring is highly advisable. Erosion quantification and monitoring can be supported by high-resolution terrestrial Light Detection and Ranging (LiDAR. In this study, a novel Geographic Information System (GIS-based method for the automatic delineation and geomorphometric description of gullies in cushion peatlands is presented. The approach is a multi-step workflow based on a gully edge extraction and a sink filling algorithm applied to a conditioned digital terrain model. Our method enables the creation of GIS-ready polygons of the gullies and the derivation of geomorphometric parameters along the entire channel course. Automatically derived boundaries and gully area values correspond to a high degree (93% with manually digitized reference polygons. The set of methods developed in this study offers a suitable tool for the monitoring and scientific analysis of fluvial morphology in cushion peatlands.

  9. Geomorphological dynamics of Deception Island (Maritime Antarctic): a GIS based analysis of the Cerro de la Cruz - Crater Lake area

    Science.gov (United States)

    Melo, R.; Vieira, G.; Rocha, J.; Caselli, A.; Batista, V.; Ramos, M.

    2009-04-01

    This study, based on field surveying from the austral summer of 2007-2008, presents the first results of the detailed geomorphological mapping of Deception Island (South Shetlands, Antarctic Peninsula). The main objective is to provide new geomorphological observations aiming to understand: i) how climate change is affecting permafrost, ii) the interactions between volcanoes and permafrost and also, iii) the present-day geomorphological dynamics in an area of high environmental sensitivity. The detailed geomorphological mapping was made in the area between the Argentinean base of Decepción and the Spanish Base Gabriel de Castilla, corresponding to 4 km2, as well as in the vicinity of the ruins of the Chilean Refuge. Mapping focused on landforms and deposits that may be indicators of permafrost dynamics, such as rockfalls, gullies, debris flows, thermokarst depressions and lag surfaces. Active layer thickness was monitored during the summer in two sites with different topographic conditions using mechanical probing. The spatial distribution of the geomorphological processes and landforms was studied using a GIS, with the objective to study the controls of several independent variables, such as altitude, aspect, slope, topographical parameters and net summer radiation.

  10. Un proyecto educativo-cultural socialista: la Fundación Cesáreo del Cerro

    Directory of Open Access Journals (Sweden)

    Francisco de LUIS MARTÍN

    2010-03-01

    Full Text Available RESUMEN: Desde un principio, los trabajos de investigación sobre el socialismo español se han centrado preferentemente en aspectos como su historia política o los grandes debates ideológicos en que se vieron envueltas sus organizaciones. Como acertadamente señala Santos Julia, razones de afición y, sobre todo, de documentación explicarían esta preferencia. Sin embargo, desde hace unos años, la ampliación del elenco de temas de estudio, por una parte, y la aparición de análisis regionales y locales, por otra, ha contribuido, cuantitativa y cualitativamente, a profundizar y clarificar las claves del socialismo en nuestro país. En este esfuerzo de clarificación de capítulos hasta hace poco olvidados merece destacarse el relativo al universo educativo-cultural de nuestro socialismo. Aunque los problemas que enfrenta este campo son abundantes y la desaparición, escasez o dispersión de fuentes no es el menor, a los trabajos ya clásicos de un buen puñado de estudiosos se suma hoy un grupo escogido de jóvenes investigadores que tratan de sistematizar los planteamientos educativos del socialismo.

  11. Effect of Measured Wellhead Parameters and Well Scaling on the Computed Downhole Conditions in Cerro Prieto Wells

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, K.P.; Miller, C.W.; Lippmann, M.J.

    1980-12-16

    This paper is devoted to the discussion of the wellbore model and its describing equations, comparison between the computed and measured pressures and the effect of measured wellhead parameters on the downhole pressures in the well. Finally a wellbore model with multiple inside diameters is discussed and the effect of well scaling on the bottom hole pressures is studied.

  12. El complejo deslizamiento de Ailinco-Cerro Papas-Las Olletas (Departamento Minas, norte del Neuquén, Argentina

    Directory of Open Access Journals (Sweden)

    E.F. González Díaz

    2003-06-01

    Full Text Available De acuerdo a los antecedentes disponibles, acumulaciones de aspecto tilloide que conforman el irregular paisaje de un amplio sector de la cuenca de drenaje del arroyo Ailinco y que se extiende al pie del extremo sur de la serranía de la Puntilla y del faldeo oeste del Cº Papas y en el paraje de las Olletas, han sido consideradas como propias de la génesis glaciaria (morenas; tills. Los autores las interpretan como correspondientes a depósitos de un complejo conjunto local de grandes movimientos gravitacionales, en el que se han distinguido tres avalanchas de rocas, siendo las mayores aquellas del Cº Las Papas y de Ailinco y otra de menor porte ocurrida en la zona de Las Olletas. Sólo se describe su distribución y sus principales características morfológicas Se propone como el promotor de los mismos a la energía sísmica, teniendo en cuenta las condiciones sismotectónicas de la región y antecedentes de otros similares movimientos cercanos, ya analizados por los autores En el mapa geomorfológico adjunto, que cubre prácticamente la totalidad del área de las cuencas de los arroyos Ailinco y Manchana Covunco, se distinguen la presencia y distribución de otras geoformas menores, cuyo origen está relacionado con procesos propios de la morfogenia glaciaria, de un ambiente local de condiciones periglaciarias actuales y de la remoción en masa.

  13. Aerial Photography and Imagery, Oblique, Published in 2009, 1:4800 (1in=400ft) scale, Cerro Gordo County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Aerial Photography and Imagery, Oblique dataset, published at 1:4800 (1in=400ft) scale as of 2009. Data by this publisher are often provided in State Plane...

  14. A prevalência do baixo peso, baixa estatura, sobrepeso e obesidade: sua evolução nas crianças de Azampay (Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    Gisel Padula

    2013-12-01

    Full Text Available This study assesses the evolution of underweight, stunting, overweight and obesity prevalence in schoolchildren from Azampay between 1995 and 2004. The sample includes children between 6 and 13 years of age (1995: 32; 2004: 42. The recorded variables were Age (A, Weight (W and Height (H. Weight-for- age (W//A, Height-for-age (H//A (WHO reference 2007, -2 SD and body mass index (BMI (The International Obesity Task Force, with the values set out therein, were estimated. Epi-Info 6.0 software was used for statistical evaluation (χ2 p ≤ 0.05%.We observed a drop in underweight to the present (from 11.54% to 3.45%. Likewise, stunting and overweight decreased (the former, from 6.25% to 0%, and the latter from 6.25% to 4.76%. Differences were not statistically significant. Obesity prevalence was zero. Overall, new strategies for survival due to the deterioration of traditional patterns of subsistence, have not adversely affected the growth of children

  15. Procesos naturales y culturales que inciden en el estado actual de conservación de los sitios de la localidad arqueológica de La Ciénaga, Departamento de Belén, Pcia. de Catamarca

    Directory of Open Access Journals (Sweden)

    Juliana Alosilla

    2006-12-01

    Full Text Available Se realiza un análisis del estado de conservación de un conjunto de sitios de la localidad arqueológica de La Ciénaga que se encuentran muy deteriorados. El deterioro es producido por procesos naturales, entre los cuales el más importante es la erosión hídrica, y por procesos culturales, entre los que se destaca el saqueo. La desertización del ambiente es un proceso debido en gran medida a factores humanos que inciden en forma indirecta en la destrucción de los sitios arqueológicos. El patrimonio cultural juega un rol importante en la provisión y construcción de un sentido de comunidad, de pasado compartido y de identidad social. Desde esta perspectiva se considera al análisis del estado de conservación de los sitios y materiales arqueológicos como un paso inicial imprescindible para una gestión integral que involucre a la investigación arqueológica y a las acciones dirigidas a conservarlos y darlos a conocer.

  16. El hormiguero con parabólica. Un estudio de las transformaciones sociomediáticas

    Directory of Open Access Journals (Sweden)

    Lic. Tania Montoro

    2000-01-01

    Full Text Available ¿Qué es un viaje? En primer lugar, un desplazamiento en el espacio. El pasaje por algún sitio. Su duración depende siempre de dos conceptos racionales: la salida y la llegada. El viajero (investigador es alguien que se encuentra suspenso entre dos referencias, que balizan el recorrido. Viajar contiene en sí el aspecto de la separación entre conocido y desconocido, viejo y nuevo. Un atajo en el tiempo, desde el mundo anterior hacia el nuevo mundo. Un atajo cuyas fronteras son puertas y ventanas, metáforas de la separación. El viajero, es ante todo, un extranjero, un intruso, un observador marginal, pero atento...

  17. Entre cerros, lagos y ciénega. Sociedad y condiciones de salud en el México prehispánico

    Directory of Open Access Journals (Sweden)

    Héctor Favila Cisneros

    2013-01-01

    Full Text Available Se comparan las condiciones de vida y salud de tres poblaciones prehispánicas mesoamericanas con ecosistemas similares, que se ubican en el Altiplano Central mexicano, a través de la observación macroscópica de osamentas y del registro de los indicadores de salud: cribra orbitalia, hiperostosis, hipoplasia del esmalte dental, así como la periostitis en estas tres series esqueléticas. Los resultados indican un porcentaje importante de problemas nutricionales en sinergia con infecciones no específicas de los sitios del Altiplano Central, así como también un porcentaje considerable de periostitis en los tres grupos analizados.

  18. Cooperación y conflicto entre empresas, comunidades, nuevos movimientos sociales y el papel del gobierno. el caso de cerro de san pedro (méxico)

    OpenAIRE

    Vargas-Hernández, José G.

    2009-01-01

    El objetivo de este trabajo es analizar las relaciones de cooperación y conflicto entre la Compañía Minera (MSX) y las comunidades de San Pedro, Soledad y San Luis Potosí, los Nuevos Movimientos Sociales y los tres niveles de gobierno involucrados. La compañía Minera inició operaciones en una mina a cielo abierto de oro y plata con el apoyo de oficiales de los gobiernos locales, estatales y federal. Los habitantes de estas comunidades apoyados por grupos ambientalistas y Organizaciones No Gub...

  19. Cooperación y conflicto entre empresas, comunidades, nuevos movimientos sociales y el papel del gobierno. El caso de Cerro de San Pedro

    OpenAIRE

    Vargas-Hernández, José G.

    2009-01-01

    El objetivo de este trabajo es analizar las relaciones de cooperación y conflicto entre la Compañía Minera (MSX) y las comunidades de San Pedro, Soledad y San Luis Potosí, los Nuevos Movimientos Sociales y los tres niveles de gobierno involucrados. La compañía Minera inició operaciones en una mina a cielo abierto de oro y plata con el apoyo de oficiales de los gobiernos locales, estatales y federal. Los habitantes de estas comunidades apoyados por grupos ambientalistas y Organizaciones No Gub...

  20. ¿Ladrones, pequeños empresarios o trabajadores independientes? : K’ajchas, trapiches y plata en el cerro de Potosí en el siglo XVIII

    NARCIS (Netherlands)

    Barragàn, R.

    2015-01-01

    This article is a contribution to the history of a group of self-employed workers that produced 20 to 35% of Potosí’s silver in the 18th century. The paper begins remembering the contribution of historiography to the study of the k’ajchas. The analysis is centered then, in the property rights to the