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Sample records for cerro prieto reservoir

  1. 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.

  2. 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.

  3. 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.

  4. Geothermal drilling in Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. 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

  6. 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.

  7. Geohydrology of the Cerro Prieto geothermal aquifer

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. An overview of the geochemistry of Cerro Prieto geothermal field with emphasis on isotopic changes

    International Nuclear Information System (INIS)

    This paper reviews the global geochemical changes in the Cerro Prieto geothermal reservoir due to exploitation and presents some important conclusions. Distribution of oxygen-18, deuterium, chloride concentrations, enthalpy and geothermometry for the field are presented

  9. Mexican--American cooperative program at the Cerro Prieto Geothermal Field

    Energy Technology Data Exchange (ETDEWEB)

    Witherspoon, P.A.; Espinosa, H.A.; Lippmann, M.J.; Mercado, A.M.; Wollenberg, H.A.

    1978-08-01

    The Cerro Prieto project incorporates studies of the geologic, hydrogeologic, geochemical, and geophysical setting of the geothermal field as well as its structural, reservoir engineering, and subsidence characteristics. A description of the activities involved in each part of this cooperative program is presented. Text of the agreement between the Comision Federal de Electricidad of Mexico and the USERDA for the cooperative study of the Cerro Prieto geothermal field is included.

  10. 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).

  11. Properties of Cerro Prieto rock at simulated in situ conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schatz, J.F.

    1981-01-01

    Rocks from the Cerro Prieto Geothermal Field were tested under simulated in situ conditions in the laboratory to determine their properties and response to pore pressure reduction as would be caused by reservoir production. The primary purpose of the project was to provide information on compaction and creep as they may contribute to surface subsidence. Results show typical compressibilities for reservoir rocks of about 1 x 10/sup -6/ psi/sup -1/ and creep compaction rates of about 1 x 10/sup -9/ sec/sup -1/ when triggered by 1000 psi pore pressure reduction. This creep rate would cause significant porosity reduction if it continued for several years. Therefore it becomes important to learn how to correctly extrapolate such data to long times.

  12. 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.

  13. 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.

  14. Radon and ammonia transects across the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Semprini, L.; Kruger, P.

    1981-01-01

    Radon and ammonia transects, conducted at the Cerro Prieto geothermal field, involve measurement of concentration gradients at wells along lines of structural significance in the reservoir. Analysis of four transects showed radon concentrations ranging from 0.20 to 3.60 nCi/kg and ammonia concentrations from 17.6 to 59.3 mg/l. The data showed the lower concentrations in wells of lowest enthalpy fluid and the higher concentrations in wells of highest enthalpy fluid. Linear correlation analysis of the radon-enthalpy data indicated a strong relationship, with a marked influence by the two-phase conditions of the produced fluid. It appears that after phase separation in the reservoir, radon achieves radioactive equilibrium between fluid and rock, suggesting that the phase separation occurs well within the reservoir. A two-phase mixing model based on radon-enthalpy relations allows estimation of the fluid phase temperatures in the reservoir. Correlations of ammonia concentration with fluid enthalpy suggests an equilibrium partitioning model in which enrichment of ammonia correlates with higher enthalpy vapor.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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 (

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. Vertical movement along the Cerro Prieto transform fault, Baja California, Mexico - a mechanism for geothermal energy renewal

    Energy Technology Data Exchange (ETDEWEB)

    Vonder Haar, S.; Noble, J.E.; Puente Cruz, I.

    1979-03-01

    Data from 53 geothermal wells to depths of 1 to 3 km on either side of the right-lateral Cerro Prieto fault, as well as geophysical data, indicate vertical displacements of this fault of 400 to 600 m. This episoidic vertical movement has offset deltaic sandstone reservoirs that are primarily at 1200 m and 1800 m depth and contain 250{sup 0} to 345{sup 0}C water. A major fracture system for convective fluid movement has been thus maintained, with production at 150 MW.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Hydraulic model and steam flow numerical simulation of the Cerro Prieto geothermal field, Mexico, pipeline network

    International Nuclear Information System (INIS)

    The development of a hydraulic model and numerical simulation results of the Cerro Prieto geothermal field (CPGF) steam pipeline network are presented. Cerro Prieto is the largest water-dominant geothermal field in the world and its transportation network has 162 producing wells, connected through a network of pipelines that feeds 13 power-generating plants with an installed capacity of 720 MWe. The network is about 125 km long and has parallel high- and low-pressure networks. Prior to this study, it was suspected that steam flow stagnated or reversed from its planned direction in some segments of the network. Yet, the network complexity and extension complicated the analysis of steam transport for adequate delivery to the power plants. Thus, a hydraulic model of the steam transportation system was developed and implemented numerically using an existing simulator, which allowed the overall analysis of the network in order to quantify the pressure and energy losses as well as the steam flow direction in every part of the network. Numerical results of the high-pressure network were obtained which show that the mean relative differences between measured and simulated pressures and flowrates are less than 10%, which is considered satisfactory. Analysis of results led to the detection of areas of opportunity and to the recommendation of changes for improving steam transport. A main contribution of the present work is having simulated satisfactorily the longest (to our knowledge), and probably the most complex, steam pipeline network in the world. - Highlights: • Extensive literature review of flow models of geothermal steam gathering networks. • Hydraulic model of the Cerro Prieto geothermal field steam network. • Selection and validation of the employed pressure-drop model. • Numerical flow simulation of the world's largest geothermal steam gathering network. • Detailed network pressure drop analysis and mapping of steam flow distribution

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. Report of the seismic activity at the Cerro Prieto B.C., Mexico, geothermal field during 1996; Reporte de la actividad sismica registrada en el campo geotermico de Cerro Prieto, B.C., Mexico, durante 1996

    Energy Technology Data Exchange (ETDEWEB)

    Escamilla Hernandez, Abelardo [Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)

    1997-05-01

    In February 1996 started the operation of the Seismic Network of Cerro Prieto Geothermal Field (RESICP). It is constituted by five digital stations with velocity sensors of three components and a natural period of one second. The network worked continuously until December 2, 1996. During this period, we located 270 events in the field area and its neighborhood, with coda-length magnitude 1Cerro Prieto Dos and Cerro Prieto Tres. The recorded activity is less than in Zone A, focal depths are between five and seven km, and the coda- length magnitude is 1Cerro Prieto volcano and to the NW of it. The activity was of swarm type mainly, and inside this zone was recorded the greater event for the region (M{sub c}=4.21, 30 August at 06:245 Universal Time), coda-length magnitude 1 Cerro Prieto (RESICP); consta de cinco estaciones de tipo digital, sensores de velocidad de tres componentes, y periodo natural de un segundo. Trabajo en forma ininterrumpida hasta el 2 de diciembre de 1996. Durante ese periodo se localizaron

  4. 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. Oxygen isotopic profiles of pore-filling calcites in sandstones appear to be a reliable measure of the recent equilibrium temperature distribution in the field before production began. From these data, a detailed, three-dimensional map has been developed, showing the equilibrium temperatures in the geothermal field. A mass balance calculation has been performed using measured /sup 18/O 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. Paleotemperatures different from the present thermal regime have been studied by examining coexisting mineral systems which exchanged their oxygen with the geothermal brines at different rates.

  5. 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.

  6. 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

  7. 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. PMID:27418073

  8. 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.

  9. 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

  10. Trace element and isotopic chemistry of the surficial hydrothermal waters in the Cerro Prieto, Geothermal Field, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Valette-Silver, J.N.; Ganje, T.J.; Bradford, G.R.; Coplen, T.

    1982-08-10

    In the Cerro Prieto Geothermal Field, five kinds of surface emissions were discovered in spring, mud pot, geysers, fumarole, and cool pool. The major element composition of the 163 fluid samples collected in 1979, was previously performed. This study was recently completed by a determination of trace element concentrations, deuterium and oxygen isotope ratios. This geochemical analysis shows, as the major elements do, that each type of surficial emission is characterized by its own unique chemistry. Each category of surface emission appears to result from different processes; trace chemistry as well as isotope composition confirm the various origins of the different surface hydrothermal fluids.

  11. 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

  12. 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.

  13. 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.

  14. Integrated model for the natural flow regime in the Cerro Prieto hydrothermal system, B. C. , Mexico, based upon petrological and isotope geochemical criteria

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-01-01

    Studies of cuttings and core 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. A map showing the first occurrence of hydrothermal epidote shows a dome-shaped top to the steam-producing zone. The hottest of the mapped mineral zones - the biotite vermiculite zone - shows a dome displaced to the northeast relative to the epidote zone. Patterns of mineral zones observed in wells are consistent with patterns of oxygen isotopic ratios in calcite and quartz. Using both criteria all of the boreholes so far studied were classified as belonging to one of four different regimes. These are: (a) the thermal plume of upward flowing water close to boiling, marked by a regular sequence of prograde mineral zones and large isotopic shifts; (b) the discharge system where fluid leaks to the surface, as indicated by the occurrence of only a few low temperature mineral zones, which extend over large depth intervals with little isotope exchange; (c) the horizontal flow zone, in which boreholes penetrate reversals of both mineral zones and isotope shifts with increasing depth; and (d) the recharge zone where cold water is descending. Plotting these four types of boreholes on a map reveals a simple, consistent, pattern. This is interpreted to have been produced by a thermal plume dipping at 45/sup 0/ to the northeast.

  15. 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

  16. 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

  17. Pressure changes and their effects on the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Bermejo M, F.J.; Navarro O, F.X.; Esquer P, C.A.; Castillo B, F.; de la Cruz D, F.C.

    1981-01-01

    Continuous extraction of the water-steam mixture at the field has been increasing to fulfill the steam requirements of the power plant. As a result, pressure declines have been observed in the producing strata in all of the wells, as well as in the geothermal reservoir as a whole. Anomalous behavior that has been observed in the wells' hydraulic columns in most cases is due to the interconnection of the various strata penetrated by the well. When this occurs, unbalanced hydraulic pressures cause the movement of fluids between the strata. As an example of this hydraulic imbalance causing the flow of fluids from an upper to a lower zone, well Nuevo Leon 1 where this effect occurs between regions 600 m apart was chosen.

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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.

  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. 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.

  5. Reservoirs

    OpenAIRE

    Nilsson, Christer

    2009-01-01

    This article provides an overview of the water reservoirs in the world. There are nearly 50 000 large dams in the world, retaining more than 6500 km3 of water. Creation of reservoirs has inundated an area like the size of France or California and has forced 40–80 million people to resettle. The majority of these reservoirs have been built during the last 50 years, but new reservoirs are still constructed at a rate of nearly one new reservoir per day. Reservoirs are used for irrigation, hydroe...

  6. The Cerro Solo Project

    International Nuclear Information System (INIS)

    The objective of the Cerro Solo Project, which was initiated in 1990, is to perform the assessment of the Co. Solo uranium ore deposit in a sequential manner. The deposit, which is located in the Patagonia Region, Argentine Republic, belongs to the sandstone type, and to the subtype coarse-grained, high energy stream. Uranium occurrences are peneconcordant, lenticular shaped and irregularly distributed in the fluvial sediments of the cretaceous Chubut Group. Resources estimated using up to present data, in tonnes of uranium recoverable at costs up to $80/kg U, are: Reasonable Assured Resources (RAR): 300 tU; Estimated Additional Resources - Category I (EAR-I): 900 tU; Estimated Additional Resources - Category II (EAR-II): 2400 tU. Resources of this ore deposit are significant to the uranium requirements in Argentina. (author). 3 refs, 6 figs

  7. 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.

  8. 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.

  9. Treatment of the Cerro Prieto I brines for use in reinjection. 2. Results of the pilot plant tests

    Energy Technology Data Exchange (ETDEWEB)

    Hurtado J, R. (Instituto de Investigaciones Electricas, Mexicali, Mexico); Mercado G, S.; Rocha C, E.; Gamino O, H.; Garibaldi P, F.

    1981-01-01

    Silica removal experiments have been carried out both in the laboratory and in pilot scale tests. The results obtained to date are presented, with special emphasis on the pilot tests with or without the use of flocculants. Previous studies on brine treatment are described briefly.

  10. Sedimentary rocks Uranium in Cerro Largo Province

    International Nuclear Information System (INIS)

    With the aim of the uranium minerals exploration has been carried out several studies by UTE technicians in Cerro Largo Province from 1968 to 1969. In uranium concentration has been found pyrite, phosphate, iron oxides and manganese in uranium. Furthermore in La Divisa Ore were studied concentration Uranium enrichment has been studied in La Divisa ore

  11. Second workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, P.; Ramey, H.J. Jr. (eds.)

    1976-12-03

    occurrences took place between the first workshop in December 1975 and this present workshop in December 1976. For one thing, the newly formed Energy Research and Development Administration (ERDA) has assumed the lead role in geothermal reservoir engineering research. The second workshop under the Stanford Geothermal Program was supported by a grant from ERDA. In addition, two significant meetings on geothermal energy were held in Rotarua, New Zealand and Taupo, New Zealand. These meetings concerned geothermal reservoir engineering, and the reinjection of cooled geothermal fluids back into a geothermal system. It was clear to attendees of both the New Zealand and the December workshop meetings that a great deal of new information had been developed between August and December 1976. Another exciting report made at the meeting was a successful completion of a new geothermal well on the big island of Hawaii which produces a geothermal fluid that is mainly steam at a temperature in excess of 600 degrees F. Although the total developed electrical power generating capacity due to all geothermal field developments in 1976 is on the order of 1200 megawatts, it was reported that rapid development in geothermal field expansion is taking place in many parts of the world. Approximately 400 megawatts of geothermal power were being developed in the Philippine Islands, and planning for expansion in production in Cerro Prieto, Mexico was also announced. The Geysers in the United States continued the planned expansion toward the level of more than 1000 megawatts. The Second Workshop on Geothermal Reservoir Engineering convened at Stanford December 1976 with 93 attendees from 4 nations, and resulted in the presentation of 44 technical papers, summaries of which are included in these Proceedings. The major areas included in the program consisted of reservoir physics, well testing, field development, well stimulation, and mathematical modeling of geothermal reservoirs. The planning forth is year

  12. Accurate Geodetic Coordinates for Observatories on Cerro Tololo and Cerro Pachon

    CERN Document Server

    Mamajek, Eric E

    2012-01-01

    As the 50th anniversary of the Cerro Tololo Inter-American Observatory (CTIO) draws near, the author was surprised to learn that the published latitude and longitude for CTIO in the Astronomical Almanac and iraf observatory database appears to differ from modern GPS-measured geodetic positions by nearly a kilometer. Surely, the position for CTIO could not be in error after five decades? The source of the discrepancy appears to be due to the ~30" difference between the astronomical and geodetic positions -- a systematic effect due to vertical deflection first reported by Harrington, Mintz Blanco, & Blanco (1972). Since the astronomical position is not necessarily the desired quantity for some calculations, and since the number of facilities on Cerro Tololo and neighboring Cerro Pachon has grown considerably over the years, I decided to measure accurate geodetic positions for all of the observatories and some select landmarks on the two peaks using GPS and Google Earth. Both sets of measurements were inter-...

  13. Accurate Geodetic Coordinates for Observatories on Cerro Tololo and Cerro Pachon

    OpenAIRE

    Mamajek, Eric E.

    2012-01-01

    As the 50th anniversary of the Cerro Tololo Inter-American Observatory (CTIO) draws near, the author was surprised to learn that the published latitude and longitude for CTIO in the Astronomical Almanac and iraf observatory database appears to differ from modern GPS-measured geodetic positions by nearly a kilometer. Surely, the position for CTIO could not be in error after five decades? The source of the discrepancy appears to be due to the ~30" difference between the astronomical and geodeti...

  14. 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.

  15. Optical atmospheric extinction over Cerro Paranal

    CERN Document Server

    Patat, F; O'Brien, K; Pompei, E; Bensby, T; Carraro, G; Postigo, A de Ugarte; Fox, A; Gavignaud, I; James, G; Korhonen, H; Ledoux, C; Randall, S; Sana, H; Smoker, J; Stefl, S; Szeifert, T

    2010-01-01

    Aims: The present study was conducted to determine the optical extinction curve for Cerro Paranal under typical clear-sky observing conditions, with an accuracy of 0.01 mag/airmass. Methods: The extinction curve of Paranal was obtained through low-resolution spectroscopy of 8 spectrophotometric standard stars observed with FORS1 mounted at the 8.2 m Very Large Telescope, covering a spectral range 3300-8000 A. A total of 600 spectra were collected on more than 40 nights distributed over six months, from October 2008 to March 2009. The average extinction curve was derived using a global fit algorithm, which allowed us to simultaneously combine all the available data. The main atmospheric parameters were retrieved using the LBLRTM radiative transfer code, which was also utilised to study the impact of variability of the main molecular bands of O2, O3, and H2O, and to estimate their column densities. Results: In general, the extinction curve of Paranal appears to conform to those derived for other astronomical si...

  16. Herpetofauna del Cerro Guiengola, Istmo de Tehuantepec, Oaxaca

    OpenAIRE

    Cintia Natalia Martín-Regalado; Rosa Ma. Gómez-Ugalde; Ma. Emma Cisneros-Palacios

    2011-01-01

    Este estudio se realizó en el Cerro Guiengola, Tehuantepec, Oaxaca, con el objetivo de contribuir al conocimiento de la herpetofauna en dicha área. Se obtuvieron 602 registros visuales y se recolectaron 103 ejemplares de anfibios y reptiles durante 60 días de trabajo de campo. Se enlistan 40 especies, pertenecientes a 33 géneros y 18 familias. Se determinó la distribución de la herpetofauna en el Cerro Guiengola por microhábitat, tipo de vegetación y altitud. Usando el método de Jaccard se el...

  17. Report of boring made in the South of Cerro Largo district (Cerro Largo) 1977-1978

    International Nuclear Information System (INIS)

    The present work are within the framework and compiles the data obtained by means of the study of the perforations executed in the District Cerro Largo Sur of the detailed prospection of uranium minerals. This study was carried out by technicians of Geologic ex--Institute of Uruguay (IGU) - at the moment National Direction of Mining and Geology. (DINAMIGE). The works began at the beginning of 1977 and continued until 1978 July; The headquarters of the program of prospection of uranium was carried out by Ing. Hector Goso. In this report the conclusions drawn at the time of the detection of the works in the District already published, as well as the litologicos cuts of all the executed perforations are included

  18. EL CERRO DE POTOSÍ Y EL DIOS PACHACÁMAC THE CERRO DE POTOSÍ AND THE PACHACÁMAC GOD

    OpenAIRE

    Teresa Gisbert

    2010-01-01

    En este trabajo se plantea que el Cerro de Potosí se ocultó a los españoles por ser el santuario más importante de la región, el cual estaba dedicado al dios Pachacámac. Los testimonios que indican que el cerro de Potosí era "Apu" (Cerro o Señor) adorado son abundantes, pero es el cronista Arzans de Orsúa y Vela (año 1736) quien dice que este "Apu" pertenecía a Pachacámac, dios del mundo subterráneo. Una tradición recogida cerca del salar de Uyuni dice lo mismo; finalmente un sacrificio reali...

  19. EL CERRO DE POTOSÍ Y EL DIOS PACHACÁMAC THE CERRO DE POTOSÍ AND THE PACHACÁMAC GOD

    Directory of Open Access Journals (Sweden)

    Teresa Gisbert

    2010-06-01

    Full Text Available En este trabajo se plantea que el Cerro de Potosí se ocultó a los españoles por ser el santuario más importante de la región, el cual estaba dedicado al dios Pachacámac. Los testimonios que indican que el cerro de Potosí era "Apu" (Cerro o Señor adorado son abundantes, pero es el cronista Arzans de Orsúa y Vela (año 1736 quien dice que este "Apu" pertenecía a Pachacámac, dios del mundo subterráneo. Una tradición recogida cerca del salar de Uyuni dice lo mismo; finalmente un sacrificio realizado en el siglo XVI a orillas del lago Titicaca en honor a Pachacámac, muestra la presencia de este dios en el Collasuyo. Cuando los incas llegaron a Potosí introdujeron el culto al Sol y cuando llegaron los españoles identificaron el cerro con la Virgen María la cual, a su vez, se identificó con la Pachamama o Madre Tierra.In this essay it is argued that "Cerro de Potosf' was hidden from the Spanish conquerors because it was the region's most important huaca or sanctuary, due to the fact that it was dedicated to the god Pachacámac. Abundant testimonies (colonial documents indicate that "Cerro de Potosf was a worshipped "Apu" (Mountain, Señor or Lord, nevertheless chronicler Orzans de Orsúa y Vela (1736 stated that this "Apu" belonged to Pachacámac, god of the underworld. A tradition collected near the Salar de Uyuni states the same; finally, a sacrifice in honor of Pachacámac that occurred during the 16th century on the shores of Lake Titicaca, shows the presence of this god in the Collasuyo. When the Incas reached Potosí, they introduced worship of the Sun, and when the Spanish conquerors arrived, they identified the "Cerro de Potosf with the Virgin Mary which at the same time was identified with Pachamama or Mother Earth.

  20. 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.

  1. The Cerro LOS Calvos and La Banderia chondrites

    Science.gov (United States)

    Whitlock, Randall; Lewis, Charles F.; Clark, James C.; Moore, Carleton B.

    1991-06-01

    The Cerro los Calvos meteorite is a single stone of 68.5 g found in the Nuevo Mercurio strewn field of Zacatecas, (Mexico). It is an unusual H4 chondrite. Its olivine (Fa12.5) and orthopyroxene (Fs 11.7, Wo 0.8) are reduced relative to typical H chondrites. The La Banderia meteorite of 54.3 g from the same vicinity is an LL5 chondrite of shock classification e.

  2. 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

  3. Report of the Cerro Chato ultrabasic geophysical studies

    International Nuclear Information System (INIS)

    This report refers to the obtained results of geophysical practiced during the year 1985 in the area of the ultrabasic of Cerro Chato, located in the area called Puntas del Malbajar in Durazno province. The aim was rehearsed an answer of an ultrabasic behaviour of the geophysical prospecting methods.They were carried out studies in magnetometry, induced polarization, electromagnetism and resistivity measurements in electric vertical sound. As well conclusions as recommendations express that applied geophysical methods allow to make ultrabasic charts or maps.

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

    International Nuclear Information System (INIS)

    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.)

  5. 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.)

  6. Fluid evolution of Cerro Colorado Porphyry Copper Mine

    Science.gov (United States)

    Tsang, Debbie Pui Wai; Wallis, Simon

    2014-05-01

    The Cerro Colorado porphyry copper deposit is the northernmost currently active copper mine in Chile, producing 90.5kt copper per year. It belongs to one of the Paleocene to early Eocene porphyry copper deposits that are distributed along the western slope of the main Andean Cordillera in Northern Chile (Bouzari & Clark, 2002). Active commercial production began in 1994, and the estimated reserves within the supergene blanket can sustain further 12 years of copper mining. Field studies of the well-exposed geology around the mine site and the access to drilled cores that penetrate into the hypogene zone provide a good opportunity to study the temporal relationship between magmatism, hypogene and supergene ore formation of the region. The geological evolution of Cerro Colorado area can be generalized as follows. The Cretaceous Cerro Empexa Formation, consisting of a sequence of volcanic rocks, mainly andesitic lava and breccia, lahars, some ignimbrite intercalations and dacitic tuff (Charrier, Pinto & Rodrigues, 2007), was intruded by tonalitic to dioritic magma in Middle-Eocene. Magmatic activities generated brecciated rocks accompanying with different alteration zones radiate outward from the intrusion. The mineralized hypogene protore later interacted with ground water, creating the supergene blanket, which is now the principal mining target of Cerro Colorado. Several plutonic lithologies with slight but distinct compositional differences were exposed in the valleys around the mine site. The presence of these several phases of small-scale intrusions suggests the ore genesis may be related to multiple pulses of heating and associated fluid flow. Complementarily, on-site geologists have reported occurrences of early stage biotites vein cutting into phyllitic alteration zone, or across terminal stage quartz-pyrite veins in the drilled cores. These observations are direct evidences of at least two major distinct phases of fluid flow, and imply the ore mineralization

  7. Reservoir management

    International Nuclear Information System (INIS)

    A reservoir's life begins with exploration leading to discovery followed by delineation of the reservoir, development of the field, production by primary, secondary and tertiary means, and finally to abandonment. Sound reservoir management is the key to maximizing economic operation of the reservoir throughout its entire life. Technological advances and rapidly increasing computer power are providing tools to better manage reservoirs and are increasing the gap between good and neutral reservoir management. The modern reservoir management process involves goal setting, planning, implementing, monitoring, evaluating, and revising plans. Setting a reservoir management strategy requires knowledge of the reservoir, availability of technology, and knowledge of the business, political, and environmental climate. Formulating a comprehensive management plan involves depletion and development strategies, data acquisition and analyses, geological and numerical model studies, production and reserves forecasts, facilities requirements, economic optimization, and management approval. This paper provides management, engineers geologists, geophysicists, and field operations staff with a better understanding of the practical approach to reservoir management using a multidisciplinary, integrated team approach

  8. Dynamic characterization of the M19 area, Cerro Negro Field, corresponding to Carabobo Block, Orinoco oil belt.

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, A. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of). E and P Orinoco Belt Division

    2009-07-01

    The Orinoco oil belt in Venezuela is divided into the Boyaca, Junin, Ayacucho and Carabobo areas. This study characterized the M19 area of the Cerro Negro Field, corresponding to Carabobo Block, one of the most prospective areas in the Orinoco oil belt. This small section of Carabobo Block involves a stock tank original oil in place of 11,000 MMSTB with an API gravity between 7.8 and 8. The initial reservoir pressure is about 1,200 psia and solution gas drive is the predominant primary production mechanism. The range of viscosities varies from 2,000 to 6,000 cps. The average porosity is 30 per cent and permeability varies from 2 to 7 Darcies. This study focused on obtaining a better understanding of the reservoir behaviour. Results from geophysics, petrophysics, sedimentology, and reservoir engineering analysis were integrated in order to characterize the area with a simulation model and to address many uncertainties which have affected exploitation of the oil field since 1980. These issues are related to vertical drainage, horizontal well spacing, and horizontal well length. The pressure model did not reveal any evidence of main compartments within the reservoir. The petrophysical properties and fluid model honours the production behaviour of the whole field. The critical gas saturation that is needed to achieve a production gas match is approximately 3 per cent. The optimum horizontal length should not exceed 4600 feet and vertical drainage suggests a well spacing of 80 ft in order to minimize interference. The cold recovery factor would increase by reducing the horizontal spacing up to 200 mts. The need for implementing a thermal and chemical process to increase the recovery factor was reinforced. 7 refs., 5 tabs., 47 figs.

  9. Report of mortmorilloniticas clay in the Medina swamp (Cerro Largo district)

    International Nuclear Information System (INIS)

    This report describes the prospect ion work for the montmorillonitics clay in the region of Medina swamp in Cerro Largo district. The existence of new deposits was detected by cartography and geological study.

  10. Hidrogeologic and geophysical studies into Agro school Melo UTU Cerro Largo province

    International Nuclear Information System (INIS)

    The technical University UTU of Uruguay requested and Hidrogeologic study with the aim to analyze the factibility to discover underground stream waters which supply groundwaters into agro school Ing Agr. Alcides E Pintos Melo, Cerro Largo province.

  11. 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.

  12. Evaluation of the physical characteristic of Cerro bend blocks used for radiation therapy

    International Nuclear Information System (INIS)

    In Radiation Therapy, the sparing of normal tissues can be performed using either multi-leaf collimators or Cerro bend blocks. The current work focuses on the physical characteristics of Cerro bend blocks including attenuation coefficient, effective penumbra width and isodose curves undulation in penumbral regions. Materials and Methods: All measurements were performed using a dual energy linac and the Cerro bend blocks designed and fabricated using a commercial Cerro bend material. Data were collected using a calibrated ionization chamber as well as EDR2 films. Results: The results showed that the attenuation coefficient was found to be 0.4475 and 0.4276 cm-1 for photon beams 6 MV and 15 MV, respectively, and a potential air bubble with a diameter greater than 3 mm affects beam attenuation significantly. The optimum Cerro bend block width was found to be around 16 mm. The isodose curves scalloping achieved for secondary collimator jaws, were also similar. Conclusion: If Cerro bend blocks are used as a basic method to protect normal tissues, its physical characteristics will be recommended to be taken into account comprehensively.

  13. Uranium and Molybdenum extraction from a Cerro Solo deposit ore

    International Nuclear Information System (INIS)

    Cerro Solo, located in Chubut, Argentina, is a sandstone type uranium-molybdenum deposit. Good recovery of both elements can be achieved by acid leaching of the ore but the presence of molybdenum in pregnant liquors is an inconvenient to uranium separation and purification. A two steps process is developed. A selective alkaline leaching of the ore with sodium hydroxide allows separating and recovering of molybdenum and after solid-liquid separation, the ore is acid leached to recover uranium. Several samples averaging 0,2% uranium and 0,1% molybdenum with variable U/Mo ratio have been used and in both steps, leaching and oxidant reagents concentration, temperature and residence time in a stirred tank leaching have been studied. In alkaline leaching molybdenum recoveries greater than 96% are achieved, with 1% uranium extraction. In acid leaching up to 93% of the uranium is extracted and Mo/U ratio in solvent extraction feed is between 0,013 and 0,025. (author)

  14. 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.

  15. 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 (<10 %) microphenocrysts of either olivine or orthopyroxene. The small compositional range and low phenocryst content indicate evolution controlled by low percentages (<10 %) of fractional crystallization of olivine and clinopyroxene of magmas similar to the least evolved rocks from the field, accompanied by assimilation during rapid ascent through the crust. Evolved 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.

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

    OpenAIRE

    Wes Hildreth; Brad Singer; Estanislao Godoy; Francisco Munizaga

    1998-01-01

    ABSTRACT 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.La edad y formación del cerro Campanario, un estratovolcán má...

  17. Evaluation of the Cerro Solo nuclear ore, province of Chubut. The Cerro Solo project within the frame of uranium exploration in Argentina. Pt. 1

    International Nuclear Information System (INIS)

    The Cerro Solo ore deposit was selected by the CNEA to invest in an assessment project because of their promising grade and amount of known and potential resources, significant to Argentina's uranium requirements. The deposit, which is located in the central region of the Chubut Province, belongs to the sandstone type and is hosted by the cretaceous Chubut Group. Technical studies carried out forecast an important growth of nuclear capacity to meet Argentina's energy requirements in the first two decades of of the the next century. To be in position to confront the challenge presented by increasing uranium resources to fuel the nuclear powers plants it is very important, as a first step, to improve the geological knowledge of uranium favorability in the country. The preliminary results of the Cerro Solo project indicate that the eastern slope of the Pichinan hills is a promising area for development of uranium resources, increasing the favorability of the San Jorge Basin in order to allow contributing to meet future uranium requirements. The Cerro Solo Project was planned in a sequential manner, as a multidisciplinary effort which includes studies on: geologic setting of mineralization, resource estimates, costs of mining and milling methods, economic analysis and environmental impact research. Among the mining methods, studies include the alternative of the in-situ leaching technology, which is becoming a low producing cost interesting possibility. (Author)

  18. Forecast of environmental impact in the evaluation of Cerro Solo nuclear mine

    International Nuclear Information System (INIS)

    This work presents a project for the study of the environmental impact of the Cerro Solo uranium mine. The survey is to be carried out performing different kinds of studies: mineralization, tectonics, hydrogeology, preliminary studies on different exploitation methods, costs, reserves estimation, economical studies and preliminary studies on possible environmental impacts. (author). 24 refs., 1 fig., 1 tab

  19. Eruptive Variations During the Emplacement of Cerro Pinto, an Ambitious Rhyolite Dome, Puebla, Mexico

    Science.gov (United States)

    Zimmer, B.; Riggs, N.; Carrasco-Nunez, G.

    2006-12-01

    Cerro Pinto is a rhyolite dome complex located in the eastern Trans-Mexican Volcanic Belt. The complex is composed of four tuff rings and four domes that were emplaced in three distinct eruptive stages marked by changes in vent location and eruptive character. Each of these stages contained eruptive sequences that follow simple rhyolite-dome models, in which a pyroclastic phase is followed immediately by effusive dome emplacement. However, some aspects of the eruptive history, such as the occurrence of explosive reactivation and dome destruction through a lateral blast are uncommon in small rhyolitic structures and are more commonly associated with polygenetic structures, such as stratovolcanoes or calderas. In these larger structures, new pulses of magma often initiate reactivation, but at Cerro Pinto the story is different. Major and trace element geochemistry suggest that Cerro Pinto was sourced by a small, isolated magma chamber, unassociated with any surrounding silicic centers and did not experience any change in chemical composition over the course of the eruption. Based on these data and field observations, it is inferred that Cerro Pinto's eruptive variations were not the result of the influx of a new magma batch, but were the result of both phreatomagmatic interactions and the presence of a small magma chamber that was zoned with respect to volatiles. Both of these factors are commonly encountered in volcanologic studies, but documentation of their influence on smaller structures is under represented. Rhyolite domes have long been considered relatively simple volcanic structures with only localized hazard implications. However, the eruptive variations displayed by Cerro Pinto suggest that isolated rhyolite dome evolutions can be much more complex with the potential for explosive reactivation and dome collapse; events that must be taken into consideration when making hazard assessments.

  20. Consideration of the ultramafic intrusive rocks in Arroyo Las Palmas (ex Cerro Chato - Las Canias) Durazno. R. O. del Uruguay

    International Nuclear Information System (INIS)

    This work is about the ultramafic rocks which its chemistry composition fluctuate since the basic to the ultra basic field and appear in the nascent of the Las Palmas stream near Las Canias and Cerro Chato district.

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

    OpenAIRE

    Cindy M. Hurtado; Víctor Pacheco

    2015-01-01

    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...

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

    OpenAIRE

    Lakicevic, Masha; Kimeswenger, Stefan; 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 ...

  3. 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.

  4. El bronce final y la Edad del Hierro en "Cerro del Berrueco" (Ávila-Salamanca

    Directory of Open Access Journals (Sweden)

    J. Francisco FABIÁN GARCÍA

    2009-10-01

    Full Text Available El Cerro del Berrueco es un monte-isla enclavado en las inmediaciones del Sistema Central y, más concretamente, de las Sierras de Gredos y Béjar, en el sector Sur-Occidental de la Meseta Norte. Corresponde una parte de él a la provincia de Avila y otra, más extensa, a la de Salamanca.

  5. Light pollution at high zenith angles, as measured at Cerro Tololo Inter-American Observatory

    CERN Document Server

    Krisciunas, Kevin; Sanhueza, Pedro; Smith, Malcolm G

    2010-01-01

    On the basis of measurements of the V-band sky brightness obtained at Cerro Tololo Inter-American Observatory in December 2006 and December 2008 we confirm the functional form of the basic model of Garstang (1989, 1991). At high zenith angles we measure an enhancement of a factor of two over Garstang's later model when there is no marine cloud layer over La Serena/Coquimbo. No corresponding enhancement is found in the B-band.

  6. Works carried out in the south of Cerro Largo district. Uranium prospection programme. Preliminary report

    International Nuclear Information System (INIS)

    During the carried out work of radimetric preliminary Investigation in the northeast of the uraniferous country were detected radimetric anonalias which are associated to the formation San Gregorio and Tres Islas. Later the works of prospection ratified those anomalies to which they defined in the environs other anomalies. The studies of revision of these conducted anomalies they took to conclude the necessity to carry out a detailed study of the area to that district was denominated Cerro Largo Sur

  7. Permeability estimation for heavy oil reservoir: an alternative approach to avoid misleading tendencies

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, L. [PDVSA (Venezuela)

    2011-07-01

    In oil production, characterization of the reservoir has to be undertaken in order to optimize the hydrocarbon production rate. Permeability is one of the most important parameters of a reservoir but estimation is difficult in heavy oil reservoirs and requires the use of multiple techniques. The objective of this paper was to evaluate the results of implementing a multi-scale permeability estimation method. Scale support effect and the physics of the measurements were looked into through a study which was conducted in Venezuela on two of PDVSA's fields, the Cerro Negro Field and the Morichal Field. Results showed that the proposed methodology captured efficiently the influence of parameters on permeability production and was successful in removing the local bias from the permeability data. The multi scale permeability estimation methodology was shown to address the issues encountered with a unique approach and to provide excellent results.

  8. Huacas olvidadas y cerros santos: Apuntes metodológicos sobre la cartografía sagrada en los Andes del sur de Bolivia

    OpenAIRE

    Pablo Cruz

    2009-01-01

    A través de la articulación de fuentes coloniales tempranas con los registros arqueológicos y etnográficos locales, hemos identificado varios cerros sacralizados y huacas prehispánicas de las regiones de Potosí y Chuquisaca (Bolivia). A partir de tres casos: los cerros Potosí y Porco, el cerro Quiquijana y el cerro Poder de Dios, se exploran y analizan las dimensiones religiosas y políticas del culto a las montañas en los Andes surandinos.A combination of early colonial sources and local arch...

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

    International Nuclear Information System (INIS)

    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. According to the burn severity map and the fire intensity map, the Cerro Grande Fire is estimated to have covered 42,885.4 acres and 42,854.7 acres, respectively. Of this, 57.0 percent was burned at low severity and 34.7 percent was burned at high severity. Similarly, 40.0 percent of the Cerro Grande Fire burned at high fire intensity, greater than 70 percent mortality, while 33.1 percent burned at moderately low intensity, 10 to 40 percent mortality. The most frequently burned cover types over the entire Cerro Grande Fire were ponderosa pine forest and mixed conifer forest, at approximately 43 percent each. However, portions of the fire that burned on Los Alamos National Laboratory (LANL) property were predominantly in ponderosa pine forests, whereas the Cerro Grande Fire burned primarily in mixed conifer forests on lands managed by other agencies. Some of the polygons of burn severities and fire intensities were extensive. The two largest burn severity polygons were 10,111 acres and 10,903 acres and these were burned at low severity. The next two largest polygons were 8999 acres (14 square miles) and 1551 acres (2.4 square miles) and both of these polygons

  10. Comentarios a las ponencias de Lourenzo Fernández Prieto y Marcela Sabaté Sort

    Directory of Open Access Journals (Sweden)

    Ricardo ROBLEDO HERNÁNDEZ

    2010-02-01

    Full Text Available La ponencia de Lorenzo Fernández Prieto empieza por reivindicar los problemas del presente como punto de partida en la construcción de la historia aconsejando tener en cuenta como referente la crisis del modelo de modernización y el fin de la ideología del progreso. Resulta llamativo que al mismo tiempo, aunque sea de forma marginal, eche una lanza a favor de Fukuyama, tildado habitualmente de ideología conservadora. Pero esto, por decirlo de algún modo, es casi una anécdota puesto que el principal foco de atención es la historia rural como el ámbito más pertinente de historia transnacional. Su ponencia es un alegato más que engrosa la corriente de opinión cada vez más caudalosa en contra de la tesis del fracaso o del excepcionalismo hispánicos. Casi hace treinta años que se está hablando en esta dirección, desde que Martínez Alier y Naredo descartaron que existiera una evolución muy diferente de la agricultura española y que el comportamiento de los grandes labradores o el carácter de las instituciones fueran factores explicativos relevantes en esa supuesta diferenciación.

  11. Status of Norris Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Norris Reservoir summarizes reservoir and watershed characteristics, reservoir uses, conditions that impair reservoir uses, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most up-to-date publications and data available, and from interviews with water resource professionals in various federal, state, and local agencies, and in public and private water supply and wastewater treatment facilities. 14 refs., 3 figs.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Geo archaeology in Cerro Lutz site, paleoenvironmental and palaeo geographic implications. Province of Entre Rios, Argentina

    International Nuclear Information System (INIS)

    The aim of this paper is to present the geo morphological evolution of the Cerro Lutz archaeological site located in the Lower Par ana Delta, Argentina River (Gualeguaychu Department). This is to add information to the paleogeographic and paleoenvironmental scheme during the occupation of site and add data to refine the regional evolution of deltaic advance against the Parana River.The geomorphology of the delta is composed of landforms resulting from fluvial modeling, coastal ( wave and tidal ) and to a lesser extent wind.They have different relative ages and dating from the late Pleistocene to the present

  14. Uranium prospecting in Cerro Partido Region-Encruzilhada do Sul Basin-RS, Brazil

    International Nuclear Information System (INIS)

    The Cerro Partido residual basin is a shallow (85 meters) and small (25km2) sedimentary basin, a remainder of the erosive cicle, enclosed in the pre-cambrian granitic rocks of the Rio Grande do Sul Shield. Grades of 0.2+ U3O8 were found in its upper-paleozoic sandstones and shales drilles for uranium. The small size and thicknesses of these concentrations prevent their economic mining. However, the different levels of the shield exposed by tectonics, the intrusive granitic, riolitic and syenitic rocks, the anomalous uranium contents in sedimentary and crystalline rocks recommend further investigations on the shield area

  15. Inestabilidad de laderas en el barrio cerros de marín, maracaibo, estado zulia, venezuela

    OpenAIRE

    Katty Montiel; Yendry González Bravo; Crismar Loaiza Arellano; Edith Gouveia Muñetón

    2008-01-01

    Se propone la aplicación de técnicas que permitan establecer una zonificación de amenaza geomorfológica para el barrio Cerros de Marín del municipio Maracaibo, expresada en términos de inestabilidad y propensión al colapso de laderas. Se efectuó un estudio de las condiciones biofísicas como litología, procesos morfogenéticos, precipitaciones y el efecto de las actividades humanas, basado en el método heurístico de Van Westen. Mediante la teledetección, inspección de campo y ...

  16. Reservoir fisheries of Asia

    International Nuclear Information System (INIS)

    At a workshop on reservoir fisheries research, papers were presented on the limnology of reservoirs, the changes that follow impoundment, fisheries management and modelling, and fish culture techniques. Separate abstracts have been prepared for three papers from this workshop

  17. 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.

  18. 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).

  19. Photosynthesis within Mars' volcanic craters?: Insights from Cerro Negro Volcano, Nicaragua

    Science.gov (United States)

    Rogers, K. L.; Hynek, B. M.; McCollom, T. M.

    2011-12-01

    Discrete locales of sulfate-rich bedrocks exist on Mars and in many cases represent the products of acid-sulfate alteration of martian basalt. In some places, the products have been attributed to hydrothermal processes from local volcanism. In order to evaluate the habitability of such an environment, we are investigating the geochemical and biological composition of active fumaroles at Cerro Negro Volcano, Nicaragua, where fresh basaltic cinders similar in composition to martian basalts are altered by acidic, sulfur-bearing gases. Temperatures at active fumaroles can reach as high as 400°C and the pH of the steam ranges from red algae that inhabit acidic, geothermal environments. Many of sequences related to Ktedonobacteria and Actinobacteria have also been found in acid mine drainage environments. The Archaeal community was far less diverse, with sequences matching those of unclassified Desulfurococcales and unclassified Thermoprotei. These sequences were more distant from isolated species than the bacterial sequences. Similar bacterial and archaeal communities have been found in hot spring environments in Yellowstone National Park, Greenland, Iceland, New Zealand and Costa Rica. Some of Mars' volcanoes were active for billions of years and by analogy to Cerro Negro, may have hosted photosynthetic organisms that could have been preserved in alteration mineral assemblages. Even on a generally cold and dry Mars, volcanic craters likely provided long-lived warm and wet conditions and should be a key target for future exploration assessing habitability.

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

    International Nuclear Information System (INIS)

    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)

  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. Status of Cherokee Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    This is the first in a series of reports prepared by Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overviews of Cherokee Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports, publications, and data available, and interviews with water resource professionals in various Federal, state, and local agencies and in public and private water supply and wastewater treatment facilities. 11 refs., 4 figs., 1 tab.

  3. Evolution of tuff ring-dome complex: the case study of Cerro Pinto, eastern Trans-Mexican Volcanic Belt

    Science.gov (United States)

    Zimmer, Brian W.; Riggs, Nancy R.; Carrasco-Núñez, Gerardo

    2010-12-01

    Cerro Pinto is a Pleistocene rhyolite tuff ring-dome complex located in the eastern Trans-Mexican Volcanic Belt. The complex is composed of four tuff rings and four domes that were emplaced in three eruptive stages marked by changes in vent location and eruptive character. During Stage I, vent clearing produced a 1.5-km-diameter tuff ring that was then followed by emplacement of two domes of approximately 0.2 km3 each. With no apparent hiatus in activity, Stage II began with the explosive formation of a tuff ring ~2 km in diameter adjacent to and north of the earlier ring. Subsequent Stage II eruptions produced two smaller tuff rings within the northern tuff ring as well as a small dome that was mostly destroyed by explosions during its growth. Stage III involved the emplacement of a 0.04 km3 dome within the southern tuff ring. Cerro Pinto's eruptive history includes sequences that follow simple rhyolite-dome models, in which a pyroclastic phase is followed immediately by effusive dome emplacement. Some aspects of the eruption, however, such as the explosive reactivation of the system and explosive dome destruction, are more complex. These events are commonly associated with polygenetic structures, such as stratovolcanoes or calderas, in which multiple pulses of magma initiate reactivation. A comparison of major and trace element geochemistry with nearby Pleistocene silicic centers does not show indication of any co-genetic relationship, suggesting that Cerro Pinto was produced by a small, isolated magma chamber. The compositional variation of the erupted material at Cerro Pinto is minimal, suggesting that there were not multiple pulses of magma responsible for the complex behavior of the volcano and that the volcanic system was formed in a short time period. The variety of eruptive style observed at Cerro Pinto reflects the influence of quickly exhaustible water sources on a short-lived eruption. The rising magma encountered small amounts of groundwater that

  4. 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

  5. Natural radiation at the Cerro Solo U-Mo deposit (Argentina)

    International Nuclear Information System (INIS)

    This paper presents results of work done to establish baseline levels of natural radiation in the vicinity of the Cerro Solo U-Mo deposit, prior to proposed uranium mining activities. This was accomplished through a number of Comision Nacional de Energia Atomica (CNEA) and International Atomic Energy Agency (IAEA) supported activities, including reprocessing and back-calibration of 1978-79 airborne gamma ray spectrometry data and acquisition of new ground gamma ray spectrometry data. The Cerro Solo U-Mo deposit is located in Chubut province in the southern Patagonia region of Argentina at 43 deg 20' south latitude and 68 deg 45' west longitude, at 630 metres above sea level. The deposit occurs as conformable layers and lenses within Cretaceous sandstone and conglomerate of Los Adobes Formation (Chubut Group). These units represent a high-energy fluvial system. The mineralized horizons occur between 60 and 120 metres below surface. Cretaceous tuffs of Cerro Barcino Formation (Chubut Group) and Jurassic andesitic rocks of the Lonco Trapial formation complement the main local geology. Regionally, a thin soil horizon is developed from the underlying bedrock. In 1978-79 the CNEA collected, under contract, approximately 100,000 line kilometres of multiparameter (gamma ray spectrometry and total field magnetic) airborne geophysical data (1) between 42 deg. - 47 deg. S and 67 deg. 30' - 70 deg. W. The survey was flown at a line spacing of 1 kilometre with a gamma ray detector volume of 48 litres. Stacked profiles and contour line maps were produced from the corrected counts for potassium, uranium and thorium. In cooperation with the IAEA and the Geological Survey of Canada (GSC) the original archive data from this survey was reprocessed and back-calibrated (2) to produce a corrected digital archive to be used for ongoing and future geological mapping, mineral exploration and environmental radiation monitoring. To support regional interpretation of the airborne geophysical

  6. Transport of reservoir fines

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander; Stenby, Erling Halfdan

    Modeling transport of reservoir fines is of great importance for evaluating the damage of production wells and infectivity decline. The conventional methodology accounts for neither the formation heterogeneity around the wells nor the reservoir fines’ heterogeneity. We have developed an integral...... dispersion equation in modeling the transport and the deposition of reservoir fines. It successfully predicts the unsymmetrical concentration profiles and the hyperexponential deposition in experiments....

  7. Stratigraphic and tectonic revision of Cerro Olivo Complex located of Southeastern of Uruguay

    International Nuclear Information System (INIS)

    This paper presents a stratigraphic and tectonic revision of Cerro Olivo Complex, located in the Southeastern part of the Uruguayan Predevonian Shield. This informal lithostratigraphic unit constitutes the country rock for the emplacement of late-orogenic granitoids, during Neoproterozoic to Cambrian times. This unit groups all the lithodemes affected by deformation and metamorphism. Recent studies indicate the presence of straight gneisses of quartzo-feldspathic composition in the coast of Maldonado Department. These rocks were interpreted as the result of intense deformation in high temperature. These tectonites base a new stratigraphic insight for the complex. They allow their lithotypes to be organized by petrotectonic features, being a function of PT conditions for every last strain process

  8. 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...

  9. Ordenación de espacios naturales: Los Cerros de Escazú (Costa Rica)

    OpenAIRE

    Zúñiga Venegas, William

    2004-01-01

    La presente tesis doctoral se realizó en Costa Rica, país del Istmo Centroamericano que ocupa el tercer lugar en extensión entre los siete países que lo integran, con un territorio de 51.100km2 y una población de 3.824.593 habitantes. De su extensión terrestre, por lo menos el 26% (13 286km2), cuenta con algún tipo de figura legal de protección ya sea ambiental o de los recursos naturales. El área específica de la investigación se localiza en la Zona Protectora de los Cerros de Escazú; que c...

  10. Using of gamma spectrometric data for geological mapping of the Berra Bonita Cerro Azul - PR - Brazil

    International Nuclear Information System (INIS)

    The present paper discuss a geological-geophysical study at Cerro Azul district, state of Parana, Brazil, in an area of 42 Km2. The district is part of the proterozoic Ribeira belt, and it contains metamorphic rocks, two syn collisional granitic intrusions (Tres Corregos and Morro Grande) as well as Mesozoic mafic dikes. Comparing geological map and gamma spectro metrical data (K, U, Th) aerial and terrestrial, it was observed that: the thorium values and profiles seem to reflect the distinct lithologies of the area; potassium maps and profiles show the contacts between granites and host rocks, as well as, the different facies at the Tres Corregos granite; comparing the U, K and Th values of the two granite bodies, Morro Grande is more radioactive. (author)

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 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.

  13. Synthesis of the works of geophysical (electrical soundings) carried out in the region of the anomalies of Yerba Sola (Cerro Largo) Uruguay

    International Nuclear Information System (INIS)

    In this report has been studied geographical localization, geology, geophysics prospection, equipment and methods used and their results in Yerba Sola anomalies Province Cerro Largo and Fraile Muerto formation

  14. Reflexiones en torno a la vulnerabilidad social y residencial de los asentamiento informales de los cerros de Valparaíso, Chile

    OpenAIRE

    Bailey, Christine; Zenteno, Elizabeth

    2015-01-01

    El incendio del pasado abril del 2014 ha abierto una serie de reflexiones respecto a las condiciones y riesgos que viven miles de familias de asentamientos informales de los cerros de Valparaíso. Aplicando una serie de entrevistas en profundidad a mujeres residentes en los cerros y quebradas, el estudio apunta a comprender las condiciones que las llevaron a habitar en aquellas zonas, visualizando el lento e infinito proceso de construcción de sus viviendas y asentamiento ...

  15. A synthesis of palynological data from the Lower Permian Cerro Pelado Formation (Parana Basin, Uruguay): A record of warmer climate stages during Gondwana glaciations

    OpenAIRE

    Beri, A.; Martínez-Blanco, X.; Mourelle, D.

    2010-01-01

    This paper presents a synthesis of the palynological record in the Cerro Pelado Formation deposits (Lower Permian, Paraná basin, Cerro Largo Department, north-eastern Uruguay) based on pre-existing data and new findings. The successions studied in this formation consist mainly of non-marine to glacial-marine mudstones and sandy mudstones. The palynological assemblages yielded by 32 samples collected from two outcrops and thirty borehole samples demonstrate that not significant floral changes ...

  16. Description of a New Galapagos Giant Tortoise Species (Chelonoidis; Testudines: Testudinidae from Cerro Fatal on Santa Cruz Island.

    Directory of Open Access Journals (Sweden)

    Nikos Poulakakis

    Full Text Available The taxonomy of giant Galapagos tortoises (Chelonoidis spp. is currently based primarily on morphological characters and island of origin. Over the last decade, compelling genetic evidence has accumulated for multiple independent evolutionary lineages, spurring the need for taxonomic revision. On the island of Santa Cruz there is currently a single named species, C. porteri. Recent genetic and morphological studies have shown that, within this taxon, there are two evolutionarily and spatially distinct lineages on the western and eastern sectors of the island, known as the Reserva and Cerro Fatal populations, respectively. Analyses of DNA from natural populations and museum specimens, including the type specimen for C. porteri, confirm the genetic distinctiveness of these two lineages and support elevation of the Cerro Fatal tortoises to the rank of species. In this paper, we identify DNA characters that define this new species, and infer evolutionary relationships relative to other species of Galapagos tortoises.

  17. Nueva edad de la base del grupo Chubut en la mena uranífera Cerro Solo, provincia del Chubut

    Directory of Open Access Journals (Sweden)

    Nilda Marveggio

    2013-09-01

    Full Text Available En este trabajo se analizan las características litológicas de la roca hospedante de la mineralización de uranio del yacimiento Cerro Solo, que corresponde al miembro inferior de la Formación Los Adobes, unidad basal del Grupo Chubut en su sector norte. Se analiza la asociación de polen angiospérmico de allí recuperada, y en base a ese análisis, se establece una edad albiana temprana para la asociación polínica, que determina una edad más joven que la considerada hasta el momento para el inicio de la depositación de las sedimentitas del Grupo Chubut en el depocentro del yacimiento Cerro Solo.

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

    OpenAIRE

    Visconti, G; Montalvo, C. I.; Goin, F J

    2000-01-01

    We describe the most complete South American marsupial association of Huayquerian Age (late Miocene). Specimens were recovered from several new localities of central and northern La Pampa province (central Argentina), at levels assignable to Cerro Azul Fm.: Bajo Giuliani, Quehué, Telén, El Guanaco, and Laguna Chillhué. Loessoid sediments studied from this formation are indicative of lacustrine deposits overlaid by eolian levels bearing evidences of pedogenesis. A study of these...

  19. ‘Looking at risk with both eyes’: health and safety in the Cerro Rico of Potosí (Bolivia)

    OpenAIRE

    Lopez-Trueba, Mei

    2014-01-01

    This thesis is concerned with core assumptions and practices in dominant approaches to Occupational Health and Safety (hereafter, OHS). I critically evaluate these through an anthropological exploration of the everyday perceptions, experiences and practices related to OHS risks amongst the cooperative miners employed in the Cerro Rico of Potosi (Bolivian Highlands). Drawing on 17 months of ethnographic fieldwork conducted between 2009 and 2011, the thesis examines the lives and livelihood...

  20. Sediment management for reservoir

    International Nuclear Information System (INIS)

    All natural lakes and reservoirs whether on rivers, tributaries or off channel storages are doomed to be sited up. Pakistan has two major reservoirs of Tarbela and Managla and shallow lake created by Chashma Barrage. Tarbela and Mangla Lakes are losing their capacities ever since first impounding, Tarbela since 1974 and Mangla since 1967. Tarbela Reservoir receives average annual flow of about 62 MAF and sediment deposits of 0.11 MAF whereas Mangla gets about 23 MAF of average annual flows and is losing its storage at the rate of average 34,000 MAF annually. The loss of storage is a great concern and studies for Tarbela were carried out by TAMS and Wallingford to sustain its capacity whereas no study has been done for Mangla as yet except as part of study for Raised Mangla, which is only desk work. Delta of Tarbala reservoir has advanced to about 6.59 miles (Pivot Point) from power intakes. In case of liquefaction of delta by tremor as low as 0.12g peak ground acceleration the power tunnels I, 2 and 3 will be blocked. Minimum Pool of reservoir is being raised so as to check the advance of delta. Mangla delta will follow the trend of Tarbela. Tarbela has vast amount of data as reservoir is surveyed every year, whereas Mangla Reservoir survey was done at five-year interval, which has now been proposed .to be reduced to three-year interval. In addition suspended sediment sampling of inflow streams is being done by Surface Water Hydrology Project of WAPDA as also some bed load sampling. The problem of Chasma Reservoir has also been highlighted, as it is being indiscriminately being filled up and drawdown several times a year without regard to its reaction to this treatment. The Sediment Management of these reservoirs is essential and the paper discusses pros and cons of various alternatives. (author)

  1. 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 <800 °C) during early stages of ascent or storage at shallower levels. Based on amphibole mineral chemistry, the felsic resident melt had a rhyolitic composition (71 ± 2 wt.% SiO2), whereas the hybrid magma, from which the amphibole rims crystallized, was dacitic (64 ± 3 wt.% SiO2). The bulk 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

  2. Reservoir characterization of Pennsylvanian sandstone reservoirs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1995-02-01

    This final report summarizes the progress during the three years of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description; (ii) scale-up procedures; (iii) outcrop investigation. The first section describes the methods by which a reservoir can be described in three dimensions. The next step in reservoir description is to scale up reservoir properties for flow simulation. The second section addresses the issue of scale-up of reservoir properties once the spatial descriptions of properties are created. The last section describes the investigation of an outcrop.

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

    Science.gov (United States)

    2016-01-01

    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. PMID:27144824

  4. 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.

  5. Monitoring the atmospheric throughput at Cerro Tololo Inter-American Observatory with aTmCam

    CERN Document Server

    Li, Ting; Marshall, J L; Nagasawa, D Q; Carona, D W; Boada, S

    2014-01-01

    We have built an Atmospheric Transmission Monitoring Camera (aTmCam), which consists of four telescopes and detectors each with a narrow-band filter that monitors the brightness of suitable standard stars. Each narrowband filter is selected to monitor a different wavelength region of the atmospheric transmission, including regions dominated by the precipitable water vapor and aerosol optical depth. The colors of the stars are measured by this multi narrow-band imager system simultaneously. The measured colors, a model of the observed star, and the measured throughput of the system can be used to derive the atmospheric transmission of a site on sub-minute time scales. We deployed such a system to the Cerro Tololo Inter-American Observatory (CTIO) and executed two one-month-long observing campaigns in Oct-Nov 2012 and Sept-Oct 2013. We have determined the time and angular scales of variations in the atmospheric transmission above CTIO during these observing runs. We also compared our results with those from a G...

  6. 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...

  7. 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 ...

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

    Science.gov (United States)

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

    1999-12-01

    Each year, Cerro Tololo Inter-American Observatory (CTIO) 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. 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 16 REU students (with 4 more coming in 2000). Thirteen (and counting) publications have resulted from CTIO REU projects; all 4 REU students in the 1999 program attended the 194th AAS meeting to present posters based on their projects. We present here an overview of the REU program at CTIO.

  9. 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.

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

    Science.gov (United States)

    Tantaleán, Henry; Stanish, Charles; Rodríguez, Alexis; Pérez, Kelita

    2016-01-01

    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. PMID:27144824

  11. Optical and infrared observations of SN 1987A from Cerro Tololo Inter-American Observatory

    International Nuclear Information System (INIS)

    Results from optical and infrared observations of SN 1987A obtained at Cerro Tololo Inter-American Observatory over the first seven months since core collapse are reviewed. Around 130 days after outburst, the bolometric light curve began to smoothly decline at a rate of ∼ 0.01 mag day-1, providing dramatic confirmation of the prediction that radioactivity had powered the optical display after the first month./ the peculiar color changes are kinks observed beginning on the 25th day probably signaled the initial release of trapped energy from mass 56 material. The bolometric luminosity of SN 1987A was unusually low at first, but reached a value more typical of other type II supernovae by the time that the final exponential decline had begun. Over much of the period covered by these observations, the optical and infrared spectra were characterized by strong absorption lines of Ba II and Sr II. Comparison with the spectra of other type II supernovae at similar stages of evolution supports the suggestion that s-processed elements were enriched in the hydrogen envelope of the progenitor, Sanduleak - 69 degrees 202

  12. 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.

  13. Optimising reservoir operation

    DEFF Research Database (Denmark)

    Ngo, Long le

    Anvendelse af optimeringsteknik til drift af reservoirer er blevet et væsentligt element i vandressource-planlægning og -forvaltning. Traditionelt har reservoirer været styret af heuristiske procedurer for udtag af vand, suppleret i en vis udstrækning af subjektive beslutninger. Udnyttelse af...... reservoirer involverer en lang række interessenter med meget forskellige formål (f.eks. kunstig vanding, vandkraft, vandforsyning mv.), og optimeringsteknik kan langt bedre lede frem til afbalancerede løsninger af de ofte modstridende interesser. Afhandlingen foreslår en række tiltag, hvormed traditionelle...... har betydning for driften af reservoiret. MIKE 11 modelsystemet er udvalgt til simulering af flodsystemet inklusiv reservoiret, mens en evolutionsbaseret algoritme i softwaresystemet AUTOCAL er benyttet som optimeringsværktøj. Herved er det blevet muligt at beregne gruppen af ikke-dominerede løsninger...

  14. Reservoir annual 1994

    International Nuclear Information System (INIS)

    Statistical information with regard to performance and reservoir parameters of provincial oil and gas pools was consolidated into a convenient reference manual. The information was subdivided into nine sections, each dealing with a specific type of reservoir data. Maps showing oil and gas pools, production areas and well spacing were presented. Reservoir data and reserves for all oil and gas pools broken down by unit and non-unit areas was also provided. Natural gas production in 1994 was 7.905 billion cubic metres, setting a new record and exceeding the previous record set in 1993 by about 10.5%. Initial reserves of gas were increased by 9.962 billion cubic metres in 1994, resulting in a net increase of 2.051 billion cubic metres and a remaining established reserves year-end value of 86.748 billion cubic meters. There were 892 new gas well completions in 1994. tabs., figs

  15. 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)

    OpenAIRE

    Violeta Soledad Di Prado; Canela Castro

    2014-01-01

    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 ...

  16. ESTUDIO ERGONÓMICO DEL PUESTO DE TRABAJO DE RECOLECTOR DE CÍTRICOS EN LA FINCA "HACIENDA EL CERRO", PERTENECIENTE A LA SOCIEDAD; EXPLOTACIONES EL CERRO S.A.

    OpenAIRE

    Guardado-Moro, José Ramón

    2013-01-01

    El objeto del TFM que me ocupa, está basado en el estudio de una empresa agraria, en concreto una empresa dedicada a la producción de cítricos, dicha empresa se denominada EXPLOTACIONES EL CERRO, S.A., cuyo centro de trabajo recibe el nombre de “finca El Cerro”. Dicha finca está compuesta de 150 hectáreas, todas ellas ocupadas por cítricos de diferentes variedades. Cada una de estas variedades tiene una época de recolección diferente, lo que permite a la empresa sacar fruta al mercado d...

  17. Subduction and exhumation structures preserved in Cerro del Almirez HP metaserpentinites (Betic Cordillera, SE Spain)

    Science.gov (United States)

    Jabaloy-Sánchez, Antonio; López Sánchez-Vizcaíno, Vicente; Gómez-Pugnaire, María Teresa; Padrón-Navarta, José Alberto; Garrido, Carlos J.

    2014-05-01

    The Cerro del Almirez massif (Nevado-Filábride Complex, Betic Cordillera, SE Spain) is composed of antigorite serpentinite and chlorite harzburgite separated by a thin reaction front in a paleo-subduction setting. Structural analysis of ultramafic lithologies and metasedimentary host rocks provides information on the tectonic evolution of this massif during prograde metamorphism in a subduction zone and during subsequent exhumation. Here we report for the first time HP structures related to a subduction event underwent by ultramafic rocks of the Nevado-Filábride Complex. The oldest subduction-related structures are preserved in Atg-serpentinites: a penetrative S1 foliation and associated L1 stretching lineation were formed in a non-coaxial regime with a top-to-the-W sense of shearing. This planar linear fabric is crosscut by olivine ± Ti-clinohumite veins formed during the prograde breakdown of brucite and pre-metamorphic clinopyroxene at temperatures ranging from 465 to 500 ºC [1]. Veins occur as a system of decimetric long joints, some of them hybrid open and sheared veins with associated drag folds. They recorded embrittlement processes due to the release of 6% vol. H2O of the rock. S1 foliation can, however, be simultaneous with or be overgrown by olivine and/or tremolite porphyroblasts, product of the prograde reaction Di + Atg → Fo + Tr + H2O, which occurred at T > 600 ºC and P = 1.7-1.9 GPa [1]. Generation of S1/L1 fabric was followed by static annealing at ca. 680 ºC and 1.6-1.9 GPa [2]. The S1/L1 fabric in Atg-serpentinite is crosscut by the Atg-out isograd and overgrown by the Atg-serpentinite dehydration products that gave place to Chl-harzburgite. Peak metamorphic conditions of the Chl-harzburgite assemblage reached 680-710 ºC and 1.6-1.9 GPa [3]. Prograde Chl-harzburgite is crosscut by sets of conjugate zones associated to grain-size reduction of olivine grains [3]. These grain size reduction zones are interpreted as brittle structures

  18. Glacier mass balance reconstruction by sublimation induced enrichment of chemical species on Cerro Tapado (Chilean Andes

    Directory of Open Access Journals (Sweden)

    P. Ginot

    2006-01-01

    Full Text Available A 36 m long ice core down to bedrock from the Cerro Tapado glacier (5536 m a.s.l, 30°08' S, 69°55' W was analyzed to reconstruct past climatic conditions for Northern Chile. Because of the marked seasonality in the precipitation (short wet winter and extended dry summer periods in this region, major snow ablation and related post-depositional processes occur on the glacier surface during summer periods. They include predominantly sublimation and dry deposition. Assuming that, like measured during the field campaign, the enrichment of chloride was always related to sublimation, the chemical record along the ice core may be applied to reconstruct the history of such secondary processes linked to the past climatic conditions over northern Chile. For the time period 1962–1999, a mean annual net accumulation of 316 mm water equivalent (weq and 327 mm weq loss by sublimation was deduced by this method. This corresponds to an initial total annual accumulation of 539 mm weq. The annual variability of the accumulation and sublimation is related with the Southern Oscillation Index (SOI: higher net-accumulation during El-Niño years and more sublimation during La Niña years. The deepest part of the ice record shows a time discontinuity; with an ice body deposited under different climatic conditions: 290 mm higher precipitation but with reduced seasonal distribution (+470 mm in winter and –180 mm in summer and –3°C lower mean annual temperature. Unfortunately, its age is unknown. The comparison with regional proxy data however let us conclude that the glacier buildup did most likely occur after the dry mid-Holocene.

  19. Water Quality Monitoring in the Cerro Solo U District Chubut, Argentina

    International Nuclear Information System (INIS)

    Full text: This work was carried out on behalf of the European Union INCO DC project called Water Quality in Mining Areas of Latin America. The Cerro Solo U district is located in Chubut province in the southern Patagonia region of Argentina at 43o20' south latitude and 68o45' west longitude, at 630 metres above sea level and covering an area of 420 square kilometers. The main deposit occurs as conformable layers and lenses within Cretaceous sandstones and conglomerates of the Los Adobes formation (Chubut Group). These units represent a high-energy fluvial system. The mineralized horizons occur between 60 and 120 metres below the surface. The average grade is 0.4% U, and the uranium resources (RAR + EAR I) are calculated in 4 600 tonnes of recoverable uranium. Cretaceous tuffs of the Cerro Barcino formation (Chubut Group) and Jurassic andesitic rocks of the Lonco Trapial formation complement the main local geology. In this area, a water quality monitoring network was established in order to evaluate the pre-mining hydro-geochemistry baseline of the district. The sampling stations include: exploration boreholes (8), springs and wells (5), streams (2) and an artesian well (1). The boreholes belong to the Cerro Solo deposit and represent the groundwater in contact with the mineralized bodies. The spring and well stations are located close to the deposit area and provide a source of water for human and animal consumption in the surrounding farms. The stream stations are located in the Chubut River, which is the only perennial stream in the region and represents the background for surface water quality. Finally, the artesian well represents a mineralized water source in the study area. In order to evaluate the seasonal variations in the water composition, the samples were collected both in the wet and dry periods of the year. Water samples were filtered (0.4 μm), and collected in pre-cleaned, high-density polyethylene bottles. Temperature, pH, Eh, dissolved oxygen

  20. La «embajada oficiosa» de Indalecio Prieto en México durante la presidencia de Lázaro Cárdenas, 1939-1940

    Directory of Open Access Journals (Sweden)

    Mateos, Abdón

    2003-08-01

    Full Text Available The author tries to set Indalecio Prieto’s mission in Cárdenas’ Mexico within its political context, emphasizing the background of the relationship between the Spanish republican socialists and the Mexican leftist nationalists and its development from the 1920’s onwards. The present monograph is an account of the JARE’s management and of President L. Cárdenas’ policy towards the Spanish republican refugees until the beginning of Ávila Camacho’s presidency

    El autor contextualiza la misión de Indalecio Prieto en el México cardenista, destacando los antecedentes de las relaciones entre los republicanos-socialistas españoles y la izquierda nacionalista mexicana establecidas desde los años veinte. La monografía analiza la gestión de la JARE y la política de Lázaro Cárdenas hacia los refugiados republicanos españoles hasta el comienzo de la presidencia de Manuel Ávila Camacho.

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

    OpenAIRE

    Edith Arias; Richard Cadenillas; Víctor Pacheco

    2011-01-01

    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 pertenecie...

  2. Palaeoenvironment reconstruction, volcanic evolution and geochronology of the Cerro Blanco subcomplex, Nevados de Chillan volcanic complex, Central Chile

    OpenAIRE

    Mee, Katy; Gilbert, Jennie S.; McGarvie, David W.; Naranjo, Jose A.; Pringle, Malcolm S.

    2009-01-01

    Nevados de Chillán Volcanic Complex, central Chile, has been active for at least 640 ka—a period spanning a number of glacial and interglacial periods. Geologic mapping, radiometric dating and geochemical analysis have identified six new volcanic units and produced four new 40Ar/39Ar ages for Cerro Blanco, the northern subcomplex of Nevados de Chillán volcano. Compositions range from dacite to basaltic-andesite and a new geologic map is presented. Examination of lava fracture structures on bo...

  3. Los marsupiales (Mammalia) del Mioceno Superior de la formación Cerro Azul (Provincia de la Pampa, Argentina)

    OpenAIRE

    Goin, Francisco Javier; Montalvo, Claudia; Visconti, G

    2000-01-01

    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 ind...

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

    OpenAIRE

    Cabrera, Paloma; Perdigones, Lorenzo

    1996-01-01

    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 regardi...

  5. TITAN2D simulations of pyroclastic flows at Cerro Machín Volcano, Colombia: Hazard implications

    Science.gov (United States)

    Murcia, H. F.; Sheridan, M. F.; Macías, J. L.; Cortés, G. P.

    2010-03-01

    Cerro Machín is a dacitic tuff ring located in the central part of the Colombian Andes. It lies at the southern end of the Cerro Bravo-Cerro Machín volcanic belt. This volcano has experienced at least six major explosive eruptions during the last 5000 years. These eruptions have generated pyroclastic flows associated with Plinian activity that have traveled up to 8 km from the crater, and pyroclastic flows associated with Vulcanian activity with shorter runouts of 5 km from the source. Today, some 21,000 people live within a 8 km radius of Cerro Machín. The volcano is active with fumaroles and has shown increasing seismic activity since 2004, and therefore represents a potentially increasing threat to the local population. To evaluate the possible effects of future eruptions that may generate pyroclastic density currents controlled by granular flow dynamics we performed flow simulations with the TITAN2D code. These simulations were run in all directions around the volcano, using the input parameters of the largest eruption reported. The results show that an eruption of 0.3 km 3 of pyroclastic flows from a collapsing Plinian column would travel up to 9 km from the vent, emplacing a deposit thicker than 60 m within the Toche River valley. Deposits >45 m thick can be expected in the valleys of San Juan, Santa Marta, and Azufral creeks, while 30 m thick deposits could accumulate within the drainages of the Tochecito, Bermellón, and Coello Rivers. A minimum area of 56 km 2 could be affected directly by this kind of eruption. In comparison, Vulcanian column-collapse pyroclastic flows of 0.1 km 3 would travel up to 6 km from the vent depositing >45 m thick debris inside the Toche River valley and more than 30 m inside the valleys of San Juan, Santa Marta, and Azufral creeks. The minimum area that could be affected directly by this kind of eruption is 33 km 2. The distribution and thickness of the deposits obtained by these simulations are consistent with the hazard

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

    OpenAIRE

    Hormaza Francisco; Vivas Oscar; Parra Alejandro

    2000-01-01

    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.

  7. Estructura, composición y diversidad de la selva baja caducifolia del Cerro Verde, Nizanda (Oaxaca), México

    OpenAIRE

    José Antonio Gallardo Cruz; Meave, Jorge A.; Eduardo A. Pérez García

    2005-01-01

    En este estudio se describe la estructura, la composición florística y los patrones de diversidad de la selva baja caducifolia del Cerro Verde, localizado en Nizanda (Istmo de Tehuantepec, Oaxaca, México). En 30 parcelas de 100 m2 se censaron las plantas leñosas con DAP #8805; 1 cm (estrato alto), y en cinco subcuadros de 4 m2 dentro de cada una se censaron las plantas con DAP 1 cm, pero con altura 30 cm (estrato bajo). Se encontraron 194 especies distribuidas en 52 familias. La riqueza de...

  8. Parallel reservoir simulator computations

    International Nuclear Information System (INIS)

    The adaptation of a reservoir simulator for parallel computations is described. The simulator was originally designed for vector processors. It performs approximately 99% of its calculations in vector/parallel mode and relative to scalar calculations it achieves speedups of 65 and 81 for black oil and EOS simulations, respectively on the CRAY C-90

  9. Chalk as a reservoir

    DEFF Research Database (Denmark)

    Fabricius, Ida Lykke

    chalk intervals are to some extent cemented and cannot compact mechanically at realistic effective stresses and only deform elastically. All chalk intervals though, may react by fracturing to changes in shear stress. So where natural fractures are not prevalent, fractures may be generated hydraulically....... Fractures play a significant role in the production of hydrocarbons from chalk reservoirs....

  10. Reinjection into geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Bodvarsson, G.S.; Stefansson, V.

    1987-08-01

    Reinjection of geothermal wastewater is practiced as a means of disposal and for reservoir pressure support. Various aspects of reinjection are discussed, both in terms of theoretical studies as well as specific field examples. The discussion focuses on the major effects of reinjection, including pressure maintenance and chemical and thermal effects. (ACR)

  11. Geothermal reservoirs - A brief review

    OpenAIRE

    Ganguly, Sayantan; Kumar, Mohan MS

    2012-01-01

    A brief discussion and review of the geothermal reservoir systems, geothermal energy and modeling and simulation of the geothermal reservoirs has been presented here. Different types of geothermal reservoirs and their governing equations have been discussed first. The conceptual and numerical modeling along with the representation of flow though fractured media, some issues related to non isothermal flow through fractured media, the efficiency of the geothermal reservoir, structure of the num...

  12. Cuerpos intrusivos asociados a las mineralizaciones polimetálicas del depósito Cerro León, área del anticlinal El Tranquilo, Santa Cruz: evidencias geofísicas Intrusive bodies associated with the polymetallic mineralization of the Cerro León deposit, area of Cerro Tranquilo anticline, Santa Cruz: Geophysical evidence

    OpenAIRE

    G. A Peñalva; S. M. Jovic; C. J. Chernicoff; D.M. Guido; I. Schalamuk

    2008-01-01

    Las características geológicas tales como presencia de cuerpos intrusivos y subvolcánicos someros básicos a intermedios y de las mineralizaciones con alto contenido de sulfuros del área del anticlinal El Tranquilo, son particulares y poco representadas en el macizo del Deseado. El depósito polimetálico vetiforme Cerro León presenta una signatura geoquímica-mineralógica que lo diferencia del clásico modelo epitermal de baja sulfuración característico del macizo del Deseado. Los datos aeromagné...

  13. Analisis neotectónico del área Cerro Salinas, departamento Sarmiento, provincia de San Juan Neotectonic analysis of the Cerro Salinas area, Sarmiento department, province of San Juan

    Directory of Open Access Journals (Sweden)

    Héctor Cisneros

    2010-12-01

    Full Text Available El cerro Salinas es una de las exposiciones más australes del basamento cristalino de las Sierras Pampeanas. Alrededor del mismo han sido reconocidos varios trazos de fallas caracterizados por escarpas rectilíneas de dirección submeridiana, que afectan a depósitos sedimentarios referidos al Terciario y Cuaternario. La actitud espacial de las fallas neotectónicas está controlada por la posición de la estratificación y de los contactos litológicos principales de las unidades terciarias, lo cual se ha interpretado preliminarmente como evidencia del flexodeslizamiento asociado al acortamiento andino. Esta situación guarda mucha similitud con el estilo de deformación de las principales zonas de fallamiento cuaternario de la Precordillera Oriental. Acorde con la distribución espacial de las deformaciones neotectónicas y de la geometría de las mismas, se dividió al área analizada en tres sectores. La principal estructura neotectónica, la falla Cerro Salinas, constituye el límite oeste tanto del cerro Salinas como de los afloramientos precuaternarios circundantes con una longitud reconocida de 15,77 km. Las observaciones realizadas en el área de estudio, principalmente al norte del mismo permiten indicar que la deformación en el frente de falla está vinculada a escarpas asociadas con fallas inversas propagantes. La discriminación cronológica de las unidades morfoestratigráficas cuaternarias se realizó en base a datos de multiparámetros y a la signatura de las superficies aluviales en imágenes Landsat ETM+ y ASTER, mediante procesamiento en base al método de componentes principales. En base a la sumatoria del desplazamiento vertical desarrollado por las escarpas de falla para el Pleistoceno tardío, se ha estimado una tasa de levantamiento mínima de 0,13 mm/año.The so called Cerro Salinas is one of the southernmost expressions of the Sierras Pampeanas crystalline basement. Several fault traces with N-S-trending rectilinear

  14. 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.

  15. Storm Water Quality in Los Alamos Canyon following the Cerro Grande Fire

    Energy Technology Data Exchange (ETDEWEB)

    M. Johansen; B. Enz; B. Gallaher; K. Mullen; D. Kraig

    2001-04-01

    In May 2000, the Cerro Grande Fire burned about 7400 acres of forest on the Los Alamos National Laboratory (LANL) and about 10,000 acres in watersheds above LANL on Santa Fe National Forest lands. The resulting burned landscapes raised concerns of increased storm water runoff and transport of contaminants by runoff in the canyons traversing LANL. On June 2 and 3, 2000, rain fell in the Los Alamos Canyon watershed generating storm water runoff in the canyon bottom. This event was important in that it was the first significant runoff on LANL following the fire and occurred in a canyon containing known legacy waste sites. Samples from this runoff were analyzed for radionuclide, metal, inorganic, and organic constituents. Results show radionuclide concentrations at or below previous (pre-fire) maximum levels at locations on LANL and downstream. However, greater concentrations of some fallout-associated radionuclides (cesium-137 and strontium-90) were seen arriving on LANL from upstream areas compared to pre-fire conditions. Tests indicate most of the radionuclides in the samples were bound to sediments, not dissolved in water. Most radionuclide concentrations in sediments were below LANL Screening Action Levels, with cesium-137 and strontium-90 as exceptions. Most radionuclide concentrations in samples taken at LANL's downstream boundary were greater than those taken upstream, indicating the presence of contributing sources on LANL. For comparison purposes, doses were calculated on a mrem per liter of unfiltered water basis for 11 radionuclides commonly associated with atmospheric fallout and with LANL operations. The maximum dose was 0.094 mrem per liter unfiltered water and was largely associated with plutonium-239/240. In contrast, all filtered samples had total doses less than 0.001 mrem per liter. Compared to past data, potential doses were not increased by the fire during this initial runoff event. Of the 25 metals tested for, seven were above pre

  16. Analysis and simulatin of rock avalanche sequence in the Cerro Caquilluco landslide (Tacna, Peru)

    Science.gov (United States)

    Crosta, Giovanni B.; Frattini, Paolo; Valbuzzi, Elena; Hermanns, Reginald L.

    2014-05-01

    The Cerro Caquilluco (Tacna, Peru) rock avalanche complex has a total volume of about 15 km3 and a length of 43 km, extending from 3900 m a.s.l to 530 m a.s.l.. Based on geomorphological interpretation and lithological evidences, we reconstructed a possible rock-avalanches sequence consisting of at least nine major events. For each event, we calculated the mobilized volumes through the comparison of pre- and post-failure morphology. We argue that the first rock avalanche event corresponds to the Cerrillos Negros rock avalanche, characterized by a distal tongue shaped lobe, 11 km long, 3 km wide and 25 to 60 m thick (rough volume estimate 1.15 km3), deposited along the piedmont surface (average slope: 2° ). The reconstruction of pristine pre-failure morphology was accomplished by mimicking the preserved morphology close to the source area, and by removing the deposited volumes from the rock avalanche path. For this, we made the hypothesis that the old paleosurface was already eroded by valleys progressively moving upstream during a wetter climate, as suggested by Hoke et al (2007) for similar conditions in northern Chile. The reconstruction of the pre-event morphology required several attempts to fit the eroded and the deposited volumes. Finally, a total mobilized volume of about 10.2 km2 was obtained for this event. For the successive scenarios of slide retrogression, we used the morphologies obtained by previous scenarios as pre-failure morphologies, and we calculated, by difference with current topography, the lobe volumes. The volumes of single rock avalanche episodes decrease from the first to the last event, roughly following a power-law decay. This behavior is comparable to that described by Utili and Crosta (2011) for retrogressive instabilities in rocky cliffs. The rock-avalanche events have been simulated, to verify the different scenarios in terms of spreading area and maximum runout, by using SPH (Smooth Particle Hydrodynamics) and Finite Element codes

  17. 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.

  18. Chalk as a reservoir

    DEFF Research Database (Denmark)

    Fabricius, Ida Lykke

    Reservoir properties of chalk depend on the primary sediment composition as well as on subsequent diagenesis and tectonic events. Chalks of the North Sea almost exclusively have mudstone or wackestone texture. Microfossils may have retained their porosity where degree of diagenesis is low, or be......, and the best reservoir properties are typically found in mudstone intervals. Chalk mudstones vary a lot though. The best mudstones are purely calcitic, well sorted and may have been redeposited by traction currents. Other mudstones are rich in very fine grained silica, which takes up pore space and...... thus reduces porosity at the same time as it increases specific surface and thus cause permeability to be low. In the Central North Sea the silica is quartzitic. Silica rich chalk intervals are typically found in the Ekofisk and Hod formations. In addition to silica, Upper Cretaceous and Palæogene...

  19. Status of Blue Ridge Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

  20. The aggressiveness of the geothermal steam controlled; La agresividad del vapor geotermico controlada

    Energy Technology Data Exchange (ETDEWEB)

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

    1989-12-31

    The first two units of Cerro Prieto have generated electric energy since 1973; in 1988 completed 15 years of continuous operation, without corrosion problems in the turbines in spite of the utilization of geothermal steam. The experience and the good results obtained during the first years of operation of these two units of 37.5 MW each, were of great help for the Cerro Prieto extension, having as of this date an installed capacity of 620 MW. [Espanol] Las dos primeras unidades de Cerro Prieto han generado energia electrica desde 1973; cumplieron 15 anos de operacion continua en 1988, sin problemas de corrosion en las turbinas a pesar del uso de vapor geotermico. La experiencia y los buenos resultados obtenidos durante los primeros anos de operacion de estas dos unidades de 37.5 MW cada una fueron de gran apoyo para la aplicacion de Cerro Prieto, teniendose a la fecha 620 MW de capacidad instalada.

  1. 40Ar/39Ar geochronology and palynology of the Cerro Negro formation, South Shetland Islands, Antarctica: a new radiometric tie for cretaceous terrestrial biostratigraphy in the southern hemisphere

    International Nuclear Information System (INIS)

    The upper part of the Jurassic-Cretaceous Byers Group, exposed on Byers Peninsula in the South Shetland Islands, Antarctica, consists of 1.4 km of non-marine strata assigned to the Cerro Negro Formation. Silicic pyroclastic units close to the base of the formation have yielded new 40Ar/39Ar ages of 120.3 ± 2.2 Ma on plagioclase from one horizon, and 119.4 ± 0.6 and 119.1± 0.8 Ma on biotite and plagioclase from a second horizon. Plagioclase from a welded ignimbrite close to the topmost exposed part of the formation has given an 40Ar/39Ar age of 119 ± 3.0 Ma. These ages indicate that the Cerro Negro Formation was deposited during a relatively short period in early Aptian times. The identification of palynomorph taxa has enabled us to propose correlations for the Cerro Negro Formation with spore/pollen zonations of South America and Australia. The presence of Interulobites pseudoreticulatus, Appendicisporites and F. wonthaggiensis in the Cerro Negro Formation supports correlation with the Interulobites-Foraminisporis and the lower part of the tectifera-corrugatus zones in southern South America. The presence of Foraminisporis asymmetricus and other palynomorphs suggests correlation with the Cyclosporites hughesii Interval Zone of early to late Aptian age in Australia. These data represent a valuable addition to the few radiometric ties available for Mesozoic terrestrial palyno-stratigraphy in the Southern Hemisphere. Copyright (1999) Blackwell Science Pty Ltd

  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. Environmental assessment of cooling reservoirs

    International Nuclear Information System (INIS)

    The environmental impacts, both adverse and beneficial, of cooling reservoirs are compared to cooling towers as an alternative closed cycle cooling system. Generally, the impacts associated with the construction of a cooling reservoir system are greater than for a comparable cooling tower system. Operational impacts are generally greater for cooling towers due to their visual impact, plus icing, fogging, and noise problems. The principle advantages of cooling reservoirs are their lower operating and maintenance costs, greater reliability, greater cooling efficiency, reduced water consumption in areas where cooling water storage is required, and their multiple use potential. A review of pertinent literature on cooling reservoir ecosystems, has revealed that entrainment, thermal, and chemical effects generally result in reduced populations of phytoplankton, zooplankton, and benthos in the vicinity of the power plant discharge. Adverse far field effects are generally less significant and are sometimes stimulatory. The overall effects of a power plant on the fish populations of cooling reservoirs appear to be minor. Based on the thermal characteristics of a model 6400 acre cooling reservoir with four 1150 MWe reactors, the ecological characteristics of the reservoir were predicted. The multiple use possibilities of cooling reservoirs provide their most significant beneficial aspect when compared to cooling towers. In addition, the cage culture of food fishes in cooling reservoirs provides an economical and practical method of commercially utilizing the waste heat discharged by power plants. For many areas of the country, cooling reservoirs appear to provide an environmentally and socially desirable alternative to cooling towers

  4. A re-appraisal of the stratigraphy and volcanology of the Cerro Galán volcanic system, NW Argentina

    Science.gov (United States)

    Folkes, Christopher B.; Wright, Heather M.; Cas, Ray A.F.; de Silva, Shanaka L.; Lesti, Chiara; Viramonte, Jose G.

    2011-01-01

    From detailed fieldwork and biotite 40Ar/39Ar dating correlated with paleomagnetic analyses of lithic clasts, we present a revision of the stratigraphy, areal extent and volume estimates of ignimbrites in the Cerro Galán volcanic complex. We find evidence for nine distinct outflow ignimbrites, including two newly identified ignimbrites in the Toconquis Group (the Pitas and Vega Ignimbrites). Toconquis Group Ignimbrites (~5.60–4.51 Ma biotite ages) have been discovered to the southwest and north of the caldera, increasing their spatial extents from previous estimates. Previously thought to be contemporaneous, we distinguish the Real Grande Ignimbrite (4.68 ± 0.07 Ma biotite age) from the Cueva Negra Ignimbrite (3.77 ± 0.08 Ma biotite age). The form and collapse processes of the Cerro Galán caldera are also reassessed. Based on re-interpretation of the margins of the caldera, we find evidence for a fault-bounded trapdoor collapse hinged along a regional N-S fault on the eastern side of the caldera and accommodated on a N-S fault on the western caldera margin. The collapsed area defines a roughly isosceles trapezoid shape elongated E-W and with maximum dimensions 27 × 16 km. The Cerro Galán Ignimbrite (CGI; 2.08 ± 0.02 Ma sanidine age) outflow sheet extends to 40 km in all directions from the inferred structural margins, with a maximum runout distance of ~80 km to the north of the caldera. New deposit volume estimates confirm an increase in eruptive volume through time, wherein the Toconquis Group Ignimbrites increase in volume from the ~10 km3 Lower Merihuaca Ignimbrite to a maximum of ~390 km3 (Dense Rock Equivalent; DRE) with the Real Grande Ignimbrite. The climactic CGI has a revised volume of ~630 km3 (DRE), approximately two thirds of the commonly quoted value.

  5. Analisis neotectónico del área Cerro Salinas, departamento Sarmiento, provincia de San Juan

    Directory of Open Access Journals (Sweden)

    Héctor Cisneros

    2010-12-01

    Full Text Available El cerro Salinas es una de las exposiciones más australes del basamento cristalino de las Sierras Pampeanas. Alrededor del mismo han sido reconocidos varios trazos de fallas caracterizados por escarpas rectilíneas de dirección submeridiana, que afectan a depósitos sedimentarios referidos al Terciario y Cuaternario. La actitud espacial de las fallas neotectónicas está controlada por la posición de la estratificación y de los contactos litológicos principales de las unidades terciarias, lo cual se ha interpretado preliminarmente como evidencia del flexodeslizamiento asociado al acortamiento andino. Esta situación guarda mucha similitud con el estilo de deformación de las principales zonas de fallamiento cuaternario de la Precordillera Oriental. Acorde con la distribución espacial de las deformaciones neotectónicas y de la geometría de las mismas, se dividió al área analizada en tres sectores. La principal estructura neotectónica, la falla Cerro Salinas, constituye el límite oeste tanto del cerro Salinas como de los afloramientos precuaternarios circundantes con una longitud reconocida de 15,77 km. Las observaciones realizadas en el área de estudio, principalmente al norte del mismo permiten indicar que la deformación en el frente de falla está vinculada a escarpas asociadas con fallas inversas propagantes. La discriminación cronológica de las unidades morfoestratigráficas cuaternarias se realizó en base a datos de multiparámetros y a la signatura de las superficies aluviales en imágenes Landsat ETM+ y ASTER, mediante procesamiento en base al método de componentes principales. En base a la sumatoria del desplazamiento vertical desarrollado por las escarpas de falla para el Pleistoceno tardío, se ha estimado una tasa de levantamiento mínima de 0,13 mm/año.

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

    Directory of Open Access Journals (Sweden)

    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

  7. 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

    OpenAIRE

    M. F. Márquez-Zavalía; M. A. Galliski

    2007-01-01

    En veta María Eugenia, Cerro Atajo, Catamarca, se encontró una asociación de minerales de estaño integrada por: chatkalita Cu6Fe2+Sn2S8, nekrasovita Cu26V2(Sn,As,Sb)6S32, colusita Cu26V2(As,Sn,Sb)6S32, kësterita Cu2(Zn,Fe)SnS4 y estannoidita Cu8(Fe,Zn)3Sn2S12. 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 ...

  8. Eruptive history of the youngest Mexican Shield and Mexico's most voluminous Holocene eruption: Cerro El Metate

    Science.gov (United States)

    Oryaëlle Chevrel, Magdalena; Guilbaud, Marie-Noelle; Siebe, Claus

    2016-04-01

    Small to medium-sized shield volcanoes are an important component of many volcanic fields on Earth. The Trans-Mexican Volcanic Belt, one of the most complex and active continental arcs worldwide, displays a large number of such medium-sized volcanoes. In particular the Michoacán-Guanajuato Volcanic Field (MGVF) situated in central Mexico, is the largest monogenetic volcanic field in the world and includes more than 1000 scoria cones and about four hundred medium-sized volcanoes, also known as Mexican shields. The Mexican shields nevertheless represent nearly 70% of the total volume erupted since 1 Ma and hence played a considerable role in the formation of the MGVF. However, the source, storage, and transport as well as the physical properties (density, viscosity, volatile content, etc.) of the magmas involved in these eruptions remain poorly constrained. Here, we focus on Cerro El Metate, the youngest monogenetic andesite shield volcano of the field. New C14 dates for the eruption yield a young age (~AD 1250), which briefly precedes the initial rise of the Tarascan Empire (AD 1350-1521) in this region. This volcano has a minimum volume of ~9.2 km3 DRE, and its viscous lava flows were emplaced during a single eruption over a period of ~35 years covering an area of 103 km2. By volume, this is certainly the largest eruption during the Holocene in Mexico, and it is the largest andesitic effusive eruption known worldwide for this period. Such a large volume of lava erupted in a relatively short time had a significant impact on the environment (modification of the hydrological network, forest fires, etc.), and hence, nearby human populations probably had to migrate. Its eruptive history was reconstructed through detailed mapping, and geochemical and rheological analyses of its thick hornblende-bearing andesitic flows. Early and late flows have distinct morphologies, chemical and mineralogical compositions, and isotopic signatures which show that these lavas were fed by

  9. Geothermal reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, C.R.; Golabi, K.

    1978-02-01

    The optimal management of a hot water geothermal reservoir was considered. The physical system investigated includes a three-dimensional aquifer from which hot water is pumped and circulated through a heat exchanger. Heat removed from the geothermal fluid is transferred to a building complex or other facility for space heating. After passing through the heat exchanger, the (now cooled) geothermal fluid is reinjected into the aquifer. This cools the reservoir at a rate predicted by an expression relating pumping rate, time, and production hole temperature. The economic model proposed in the study maximizes discounted value of energy transferred across the heat exchanger minus the discounted cost of wells, equipment, and pumping energy. The real value of energy is assumed to increase at r percent per year. A major decision variable is the production or pumping rate (which is constant over the project life). Other decision variables in this optimization are production timing, reinjection temperature, and the economic life of the reservoir at the selected pumping rate. Results show that waiting time to production and production life increases as r increases and decreases as the discount rate increases. Production rate decreases as r increases and increases as the discount rate increases. The optimal injection temperature is very close to the temperature of the steam produced on the other side of the heat exchanger, and is virtually independent of r and the discount rate. Sensitivity of the decision variables to geohydrological parameters was also investigated. Initial aquifer temperature and permeability have a major influence on these variables, although aquifer porosity is of less importance. A penalty was considered for production delay after the lease is granted.

  10. Calderas and magma reservoirs

    Science.gov (United States)

    Cashman, Katharine V.; Giordano, Guido

    2014-11-01

    Large caldera-forming eruptions have long been a focus of both petrological and volcanological studies; petrologists have used the eruptive products to probe conditions of magma storage (and thus processes that drive magma evolution), while volcanologists have used them to study the conditions under which large volumes of magma are transported to, and emplaced on, the Earth's surface. Traditionally, both groups have worked on the assumption that eruptible magma is stored within a single long-lived melt body. Over the past decade, however, advances in analytical techniques have provided new views of magma storage regions, many of which provide evidence of multiple melt lenses feeding a single eruption, and/or rapid pre-eruptive assembly of large volumes of melt. These new petrological views of magmatic systems have not yet been fully integrated into volcanological perspectives of caldera-forming eruptions. Here we explore the implications of complex magma reservoir configurations for eruption dynamics and caldera formation. We first examine mafic systems, where stacked-sill models have long been invoked but which rarely produce explosive eruptions. An exception is the 2010 eruption of Eyjafjallajökull volcano, Iceland, where seismic and petrologic data show that multiple sills at different depths fed a multi-phase (explosive and effusive) eruption. Extension of this concept to larger mafic caldera-forming systems suggests a mechanism to explain many of their unusual features, including their protracted explosivity, spatially variable compositions and pronounced intra-eruptive pauses. We then review studies of more common intermediate and silicic caldera-forming systems to examine inferred conditions of magma storage, time scales of melt accumulation, eruption triggers, eruption dynamics and caldera collapse. By compiling data from large and small, and crystal-rich and crystal-poor, events, we compare eruptions that are well explained by simple evacuation of a zoned

  11. [Human reservoirs of Pneumocystis].

    Science.gov (United States)

    Wissmann, Gustavo; Morilla, Ruben; Friaza, Vicente; Calderón, Enrique; Varela, Jose M

    2010-01-01

    Pneumocystis jirovecii, the fungal agent that causes Pneumocystis pneumonia (PCP), is known to exclusively infect humans. Molecular studies have enabled detection of this fungus in individuals who have been colonized by P. jirovecii. Such colonization, found in several populations, seems to act as a human reservoir for the fungus. Various studies have reported mutations associated with sulfa resistance in P. jirovecii strains isolated from colonized patients, who can transmit the mutant genotype to PCP-susceptible individuals. The growing interest in P. jirovecii colonization may prompt the design of new prevention and management strategies for PCP. PMID:19403207

  12. Reservoir management cost-cutting

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, M.S.

    1996-12-31

    This article by Mohinder S. Gulati, Chief Engineer, Unocal Geothermal Operations, discusses cost cutting in geothermal reservoir management. The reservoir engineer or geoscientist can make a big difference in the economical outcome of a project by improving well performance and thus making geothermal energy more competitive in the energy marketplace. Bringing plants online in less time and proving resources to reduce the cycle time are some of the ways to reduce reservoir management costs discussed in this article.

  13. Encapsulated microsensors for reservoir interrogation

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  14. Tracer testing for reservoir description

    Energy Technology Data Exchange (ETDEWEB)

    Brigham, W.E.; Abbaszadeh-Dehghani, M.

    1987-05-01

    When a reservoir is studied in detail for an EOR project, well-to-well tracers should be used as a tool to help understand the reservoir in a quantitative way. Tracers complement the more traditional reservoir evaluation tools. This paper discusses the concepts underlying tracer testing, the analysis methods used to produce quantitative results, and the meaning of these results in terms of conceptual picture of the reservoir. Some of the limitations of these analysis methods are discussed, along with ongoing research on tracer flow.

  15. Tracer testing for reservoir description

    International Nuclear Information System (INIS)

    When a reservoir is studied in detail for an EOR project, well-to-well tracers should be used as a tool to help understand the reservoir in a quantitative way. Tracers complement the more traditional reservoir evaluation tools. This paper discusses the concepts underlying tracer testing, the analysis methods used to produce quantitative results, and the meaning of these results in terms of conceptual picture of the reservoir. Some of the limitations of these analysis methods are discussed, along with ongoing research on tracer flow

  16. Reservoir geochemistry; Geoquimica de reservatorios

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Joelma Pimentel; Rangel, Mario Duncan; Morais, Erica Tavares de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)], Emails: joelma.lopes@petrobras.com.br, mduncan@petrobras.com.br, ericat@petrobras.com.br; Aguiar, Helen G.M. de [Fundacao GORCEIX, Ouro Preto, MG (Brazil)], E-mail: helenaguiar.GORCEIX@petrobras.com.br

    2008-03-15

    Reservoir Geochemistry has many important practical applications during petroleum exploration, appraisal and development of oil fields. The most important uses are related to providing or disproving connectivity between reservoirs of a particular well or horizon. During exploration, reservoir geochemistry can indicate the direction of oil filling, suggesting the most appropriate places for drilling new wells. During production, studies of variations in composition with time and determination of proportions of commingled production from multiple zones, may also be carried out. The chemical constituents of petroleum in natural reservoirs frequently show measurable compositional variations, laterally and vertically. Due to the physical and chemical nature of petroleum changes with increasing maturity (or contribution of a second source during the filling process), lateral and vertical compositional variations exist in petroleum columns as reservoir filling is complete. Compositional variation can also be introduced by biodegradation or water washing. Once the reservoir is filled, density driven mixing and molecular diffusion tend to eliminate inherited compositional variations in an attempt to establish mechanical and chemical equilibrium in the petroleum column (England, 1990). Based on organic geochemical analysis it is possible to define these compositional variations among reservoirs, and use these data for developing of petroleum fields and for reservoir appraisal. Reservoir geochemistry offers rapid and low cost evaluation tools to aid in understanding development and production problems. Moreover, the applied methodology is relatively simple and gives reliable results, and can be performed routinely in any good geochemical laboratory at a relatively low cost. (author)

  17. Evaluation of the Cerro Solo nuclear ore, province of Chubut. On the economic parameters of the deposit. Pt. 3

    International Nuclear Information System (INIS)

    Preliminary results of the resources estimation carried out in the Cerro Solo uranium ore deposit, located in the Chubut Province, 1900 km SW from Buenos Aires and 380 Km W from Trelew, presented in tonnes of uranium recoverable at costs up to U$S 80/kgU, are as follows: a) Reasonable assured resources (indicated): 800 tU; b) Estimates Additional Resources (inferred): 2200 tU. Economic evaluation at the order-of-magnitude level, performed using the grade-tonnage model of the deposit, resulted a useful tool in the different stages of the project to identify the influence of technical parameters on the potential profitability. Research about feasibility of in-situ leaching method of exploitation for this deposit introduces an interesting alternative for future uranium production in the country. (Author)

  18. 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.

  19. Charnockitic ortho gneisses and mafic granulites of Cerro Olivo complex, proterozoic basement of SE Uruguay, Part 1: Geology

    International Nuclear Information System (INIS)

    Charnockitic ortho gneisses and mafic granulite s exposed in the Cerro Bori Block, in the center of Punta del Este terrain, were the first document occurrence of granulitic rocks from SE sector of the Uruguayan Shield. We present here their main geological features, with the purpose to suggest some petrologic and structural interesting problems for a future lithogeochemical, mineral chemistry, stable isotopes and fluid inclusion studies about these rocks. We propose some speculation form field-based studies considering a cognate magmatic origin of both kinds of rocks, previous to a homogeneous granulitic metamorphism. Some structural evidences indicate that after their uplift, these rocks were located on over thickened crust, at great to medium deepness. A cataclasis during anatexis and amphibolite-facies mineral association stabilization are common phenomena. Other evidences suggest a polycyclic character for the regional geologic evolution

  20. 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.

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    Visconti, G.

    2000-04-01

    Full Text Available We describe the most complete South American marsupial association of Huayquerian Age (late Miocene. Specimens were recovered from several new localities of central and northern La Pampa province (central Argentina, at levels assignable to Cerro Azul Fm.: Bajo Giuliani, Quehué, Telén, El Guanaco, and Laguna Chillhué. Loessoid sediments studied from this formation are indicative of lacustrine deposits overlaid by eolian levels bearing evidences of pedogenesis. A study of these levels at each one of the new localities led to their correlation in an integrated profile of Cerro Azul Fm. This formation corresponds to «Epecuén Fm.», at least in Salinas Grandes de Hidalgo, and probably also to the upper levels of Arroyo Chasicá Fm. The studied marsupials are representative of almost all major lineages (orders of South American Neogene marsupials. The marmosine didelphid Zygolestes tatei sp. nov. differs from the type species of the genus in its larger size, unreduced third lower premolar, and in the less reduction of the metaconid in the last lower molar. Another marmosine, Thylamys pinei sp. nov., differs from other Marmosini in the twinning of the para- and metaconid in the lower molars, and in the wider talonid of the m4. The Monodelphini marmosines Thylatheridium hudsoni y T. dolgopolae are abundant in several localities of this formation; their study confirms close affinities between this genus and Monodelphis. The didelphines Hyperdidelphys pattersoni and an indeterminate species of Lutreolina are also represented by a few specimens. A mandibular fragment including part of the last molar may represent the oldest record of a Sparassocynidae in central Argentina. The Borhyaenidae and Thylacosmilidae (Sparassodonta are also recorded by a few, fragmentary specimens. Pliolestes venetus sp. nov. (Paucituberculata, Caenolestidae differs from the type species of the genus in its smaller size and in the larger, less displaced metaconid in the

  3. 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

  4. Development of the Cerro solo deposit and uranium favorability of the San Jorge Gulf Basin, province of Chubut

    International Nuclear Information System (INIS)

    In the future the uranium exploration activities of CNEA would tend to improve the knowledge of geology and uranium favorability; to perform prospection tasks, and research and development in exploration technologies, to contribute to be in a position to meet the requirements of the country in the long term. On the other hand, a strong growth of nuclear capacity is expected in the first two decades of the next century. Based on its promising grade, the Cerro Solo uranium ore deposit was selected in 1990 by the CNEA to carry out an assessment project. The intensive exploration level was accomplished, as follows: definition of general characteristics of the main orebodies; detailed geologic studies; estimation of resources with adequate data; and preliminary selection of mining-milling methods to estimate the potential profitability of the project. The deposit belongs to the sandstone type. The mineralized layers are distributed into the fluvial sandstones and conglomerates of the cretaceous Chubut Group, lying 50 to 130 m deep Resources of the deposit, with an average grade of 0.3% U, in tonnes of recoverable uranium at costs of up to $80/kg U, are: Reasonable Assured Resources (RAR): 800 t U, Estimated Additional Resources, Category I (EAR-I): 2100 t U. Follow-up drilling programmes are being performed at present in some of the target sites defined in the paleochannel that hosts the Cerro Solo deposit, in order to establish the hypothetical resources of the area. The sites were determined as a result of the exploration that CNEA conducted in the Pichinan uranium district. Recently a regional research project was formulated, for the detailed exploration in the San Jorge Gulf Basin, where the Chubut Group is distributed. 17 refs, 4 figs

  5. Cesium reservoir and interconnective components

    International Nuclear Information System (INIS)

    The program objective is to demonstrate the technology readiness of a TFE (thermionic fuel element) suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW range. A thermionic converter must be supplied with cesium vapor for two reasons. Cesium atoms adsorbed on the surface of the emitter cause a reduction of the emitter work function to permit high current densities without excessive heating of the emitter. The second purpose of the cesium vapor is to provide space-charge neutralization in the emitter-collector gap so that the high current densities may flow across the gap unattenuated. The function of the cesium reservoir is to provide a source of cesium atoms, and to provide a reserve in the event that cesium is lost from the plasma by any mechanism. This can be done with a liquid cesium metal reservoir in which case it is heated to the desired temperature with auxiliary heaters. In a TFE, however, it is desirable to have the reservoir passively heated by the nuclear fuel. In this case, the reservoir must operate at a temperature intermediate between the emitter and the collector, ruling out the use of liquid reservoirs. Integral reservoirs contained within the TFE will produce cesium vapor pressures in the desired range at typical electrode temperatures. The reservoir material that appears to be the best able to meet requirements is graphite. Cesium intercalates easily into graphite, and the cesium pressure is insensitive to loading for a given intercalation stage. The goals of the cesium reservoir test program were to verify the performance of Cs-graphite reservoirs in the temperature-pressure range of interest to TFE operation, and to test the operation of these reservoirs after exposure to a fast neutron fluence corresponding to seven year mission lifetime. In addition, other materials were evaluated for possible use in the integral reservoir

  6. Cuerpos intrusivos asociados a las mineralizaciones polimetálicas del depósito Cerro León, área del anticlinal El Tranquilo, Santa Cruz: evidencias geofísicas Intrusive bodies associated with the polymetallic mineralization of the Cerro León deposit, area of Cerro Tranquilo anticline, Santa Cruz: Geophysical evidence

    Directory of Open Access Journals (Sweden)

    G. A Peñalva

    2008-03-01

    Full Text Available Las características geológicas tales como presencia de cuerpos intrusivos y subvolcánicos someros básicos a intermedios y de las mineralizaciones con alto contenido de sulfuros del área del anticlinal El Tranquilo, son particulares y poco representadas en el macizo del Deseado. El depósito polimetálico vetiforme Cerro León presenta una signatura geoquímica-mineralógica que lo diferencia del clásico modelo epitermal de baja sulfuración característico del macizo del Deseado. Los datos aeromagnéticos del área del anticlinal El Tranquilo permiten reconocer una conspicua anomalía subcircular que se interpreta como un intrusivo no aflorante, de aproximadamente 9 km de diámetro, que subyace al Grupo El Tranquilo y a la Formación Roca Blanca; su profundidad se estima en 1400 m. Este cuerpo intrusivo genera el domamiento regional del anticlinal El Tranquilo y el fracturamiento radial asociado. La interpretación de la presencia de pequeños cuerpos intrusivos y subvolcánicos o apófisis alimentados por el cuerpo intrusivo mayor, asociados con anomalías magnéticas de menor diámetro y mayor gradiente, está confirmada por datos de perforación. Las principales vetas del depósito Cerro León se ubican asociadas espacialmente con los cuerpos intrusivos y subvolcanicos someros no aflorantes. Esto, sumado al alto contenido de sulfuros y la signatura geoquímica y mineralógica de las vetas, sugiere que posiblemente estén asociadas genéticamente a los cuerpos intrusivos subyacentes y circundantes, y permite utilizar este modelo como una herramienta de prospección para este tipo de depósitos.The geologic characteristics such as presence of basic to intermediate intrusive and subvolcanic bodies, and the mineralization with high sulfide content of the El Tranquilo anticline area are peculiar and poorly represented in the Deseado Massif. The Cerro León polymetallic deposit presents a geochemical and mineralogical signature that is

  7. Decree 343/012. Is regulated the servitude established by Decree-Law 10,383, on several lines of electricity conduction -150 KV to be built in the departments of Florida, Cerro Largo, Maldonado, Flores, San Jose and Tacuarembo

    International Nuclear Information System (INIS)

    This decree regulates the establishment of electricity conduction in Florida, Cerro Largo, Maldonado, Flores, San Jose and Tacuarembo towns. These electrical lines are necessary to provide the public service by UTE

  8. Reservoir engineering and hydrogeology

    International Nuclear Information System (INIS)

    Summaries are included which show advances in the following areas: fractured porous media, flow in single fractures or networks of fractures, hydrothermal flow, hydromechanical effects, hydrochemical processes, unsaturated-saturated systems, and multiphase multicomponent flows. The main thrust of these efforts is to understand the movement of mass and energy through rocks. This has involved treating fracture rock masses in which the flow phenomena within both the fractures and the matrix must be investigated. Studies also address the complex coupling between aspects of thermal, hydraulic, and mechanical processes associated with a nuclear waste repository in a fractured rock medium. In all these projects, both numerical modeling and simulation, as well as field studies, were employed. In the theoretical area, a basic understanding of multiphase flow, nonisothermal unsaturated behavior, and new numerical methods have been developed. The field work has involved reservoir testing, data analysis, and case histories at a number of geothermal projects

  9. FRACTURED PETROLEUM RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Abbas Firoozabadi

    1999-06-11

    The four chapters that are described in this report cover a variety of subjects that not only give insight into the understanding of multiphase flow in fractured porous media, but they provide also major contribution towards the understanding of flow processes with in-situ phase formation. In the following, a summary of all the chapters will be provided. Chapter I addresses issues related to water injection in water-wet fractured porous media. There are two parts in this chapter. Part I covers extensive set of measurements for water injection in water-wet fractured porous media. Both single matrix block and multiple matrix blocks tests are covered. There are two major findings from these experiments: (1) co-current imbibition can be more efficient than counter-current imbibition due to lower residual oil saturation and higher oil mobility, and (2) tight fractured porous media can be more efficient than a permeable porous media when subjected to water injection. These findings are directly related to the type of tests one can perform in the laboratory and to decide on the fate of water injection in fractured reservoirs. Part II of Chapter I presents modeling of water injection in water-wet fractured media by modifying the Buckley-Leverett Theory. A major element of the new model is the multiplication of the transfer flux by the fractured saturation with a power of 1/2. This simple model can account for both co-current and counter-current imbibition and computationally it is very efficient. It can be orders of magnitude faster than a conventional dual-porosity model. Part II also presents the results of water injection tests in very tight rocks of some 0.01 md permeability. Oil recovery from water imbibition tests from such at tight rock can be as high as 25 percent. Chapter II discusses solution gas-drive for cold production from heavy-oil reservoirs. The impetus for this work is the study of new gas phase formation from in-situ process which can be significantly

  10. Reservoir Systems in Changing Climate

    Science.gov (United States)

    Lien, W.; Tung, C.; Tai, C.

    2007-12-01

    Climate change may cause more climate variability and further results in more frequent extreme hydrological events which may greatly influence reservoir¡¦s abilities to provide service, such as water supply and flood mitigation, and even danger reservoir¡¦s safety. Some local studies have identified that climate change may cause more flood in wet period and less flow in dry period in Taiwan. To mitigate climate change impacts, more reservoir space, i.e. less storage, may be required to store higher flood in wet periods, while more reservoir storage may be required to supply water for dry periods. The goals to strengthen adaptive capacity of water supply and flood mitigation are conflict under climate change. This study will focus on evaluating the impacts of climate change on reservoir systems. The evaluation procedure includes hydrological models, a reservoir water balance model, and a water supply system dynamics model. The hydrological models are used to simulate reservoir inflows under different climate conditions. Future climate scenarios are derived from several GCMs. Then, the reservoir water balance model is developed to calculate reservoir¡¦s storage and outflows according to the simulated inflows and operational rules. The ability of flood mitigation is also evaluated. At last, those outflows are further input to the system dynamics model to assess whether the goal of water supply can still be met. To mitigate climate change impacts, the implementing adaptation strategies will be suggested with the principles of risk management. Besides, uncertainties of this study will also be analyzed. The Feitsui reservoir system in northern Taiwan is chosen as a case study.

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

    Directory of Open Access Journals (Sweden)

    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. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)

    2006-11-01

    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  13. The rules of urban planning and administrative responsibilities in protecting to the vulnerability and risk of Cerro Tapezco in Santa Ana

    International Nuclear Information System (INIS)

    An analysis of regulation is made of land use and administrative management of the Cerro Tapezco to show that as the years have passed it has been verified that the Costa Rican law on town planning has been inadequate for current problems due to lack of updating of various scientific and technical sources also dispersion and proliferation of competences of administrative authorities. The physical setting and planning rules is identified for CerroTapezco and surrounding towns. Local actions are explored in the elaboration of improvement and reform of the regulatory plan of Santa Ana. The administrative entities and institutions with competence in the development and implementation of plans have been identified, assessing deficiencies, inconsistencies and administrative omissions in urban planning of the city of Santa Ana and recommending changes necessary for the proper application of the Costa Rican law

  14. Caracterización arqueométrica de cerámicas ibéricas de los yacimientos de Alarcos y El Cerro de las Cabezas

    OpenAIRE

    Guirao Polo, David

    2014-01-01

    En la presente Tesis Doctoral se han analizado arqueométricamente 146 fragmentos de cerámicas de época ibérica procedentes de los yacimientos del Cerro de Alarcos (Ciudad Real) y de El Cerro de las Cabezas (Valdepeñas, Ciudad Real). A partir del análisis químico-estadístico, mineralógico, térmico y microscópico, se ha identificado la existencia de grupos cerámicos, con características propias e identificativas, que deben vincularse a la producción cerámica de uno y otro poblado. El establecim...

  15. Evaluation of the Cerro Solo nuclear ore, province of Chubut. Geological characteristics of the deposit and of the basin. Pt. 2

    International Nuclear Information System (INIS)

    The Cerro Solo uranium ore deposit, is located 420 km west from Trelew city, Chubut province, in the extra-andean. The geologic environment belongs to the northwest edge portion of the intracratonic San Jorge Gulf Basin. The uraniferous district is named Pichinanes Ridge district. The mineralization lies 25 to 130 m depth, and is hosted by Los Adobes formation aged Aptian-Albian, made up by conglomerates, sandstones, coarse-sandstones and less abundant siltstones and claystones. The Cerro Solo ore deposit that belongs to the sandstone type-uranium occurrences are lenticular or tabular shaped, associated with organic material and pyrite, generally roughly parallel to the bedding (Trend-Type). The uranium minerals are uraninite and coffinite associated with organic material and pyrite, and frequently hematite, goethite, calcite, siderite and barite are observed. (Author)

  16. Effects of the Cerro Grande Fire (Smoke and Fallout Ash) on Soil Chemical Properties Within and Around Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Fresquez, P.R.; Velasquez, W.R.; Naranjo, L. Jr.

    2000-11-01

    Soil surface (0- to 2-in. depth) samples were collected from areas within and around Los Alamos National Laboratory (LANL) just after the Cerro Grande fire, analyzed for radionuclides, radioactivity, and trace elements (heavy metals), and compared to soil samples collected in 1999 from the same sites. In addition, many types of organic substances (volatile and semivolatile organic compounds, organochlorine pesticides, polychlorinated biphenyls, high explosives, and dioxin and dioxin-like compounds) were assessed in soils from LANL, perimeter, and regional sites after the fire. Results show that impacts to regional, perimeter, and on-site (mesa top) areas from smoke and fallout ash as a result of the Cerro Grande fire were minimal.

  17. TRITIUM RESERVOIR STRUCTURAL PERFORMANCE PREDICTION

    Energy Technology Data Exchange (ETDEWEB)

    Lam, P.S.; Morgan, M.J

    2005-11-10

    The burst test is used to assess the material performance of tritium reservoirs in the surveillance program in which reservoirs have been in service for extended periods of time. A materials system model and finite element procedure were developed under a Savannah River Site Plant-Directed Research and Development (PDRD) program to predict the structural response under a full range of loading and aged material conditions of the reservoir. The results show that the predicted burst pressure and volume ductility are in good agreement with the actual burst test results for the unexposed units. The material tensile properties used in the calculations were obtained from a curved tensile specimen harvested from a companion reservoir by Electric Discharge Machining (EDM). In the absence of exposed and aged material tensile data, literature data were used for demonstrating the methodology in terms of the helium-3 concentration in the metal and the depth of penetration in the reservoir sidewall. It can be shown that the volume ductility decreases significantly with the presence of tritium and its decay product, helium-3, in the metal, as was observed in the laboratory-controlled burst tests. The model and analytical procedure provides a predictive tool for reservoir structural integrity under aging conditions. It is recommended that benchmark tests and analysis for aged materials be performed. The methodology can be augmented to predict performance for reservoir with flaws.

  18. Estudio petrográfico de las facies piroclásticas de la Formación Cerro Varela en el sur de la Sierra de San Luis Petrographic study of the pyroclastic facies of the Cerro Varela Formation in the south of the Sierra de San Luis

    Directory of Open Access Journals (Sweden)

    Amancay N. Martínez

    2010-11-01

    Full Text Available En la provincia de San Luis, existen tres sub-cuencas denominadas Las Salinas, Beazley y Mercedes. Estas cuencas corresponden a depocentros de rift elongados en sentido NO, que alojan rocas ígneas de edad triásica con espesores que llegan hasta los 4.000 metros. Las rocas ígneas de la Formación Cerro Varela forman parte del cerro homónimo que constituye los últimos asomos australes de la sierra de San Luis. Las riolitas triásicas que afloran en la sierra de Varela se disponen dentro de un esquema estructural extensional asociado a la formación de cuencas de tipo rift. Las unidades analizadas de la Formación Cerro Varela están compuestas por tobas cristalinas tanto de alto grado como de bajo grado de soldadura, de composición riolítica e interpretadas como depósitos originados por flujos piroclásticos. Por su litología, edad y contexto regional, las rocas de la Formación Cerro Varela integran el magmatismo gondwánico del Grupo Choiyoi de edad permotriásica de la Cordillera Frontal de Mendoza y San Juan.In the San Luis province, there are three sub-basins called Las Salinas, Beazley and Mercedes. These basins correspond to elongated rift depocenter with a NO orientation that host Triassic igneous rocks with thicknesses that reach 4,000 meters. The igneous rocks from Cerro Varela Formation, part of the homonym hill, is the last vestige of the southern Sierra San Luis. The Triassic rhyolites that crop up in the sierra de Varela, are placed within a structural pattern associated with the formation of extensional basins. Crystal tuffs of Cerro Varela are corresponds to tuffs with high and low degree of welding, of rhyolitic composition and interpreted as pyroclastic deposits. For its lithology, age and regional context, the rocks of the Cerro Varela Formation integrate the Gondwanic magmatism of Permo-Triassic age, related to the Choiyoi Group of the Cordillera Frontal of Mendoza and San Juan.

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

    International Nuclear Information System (INIS)

    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.

  20. Moche social boundaries and settlement dynamics at Cerro Castillo (c. AD 600-1000), Nepeña Valley, Peru Volume 1

    OpenAIRE

    Rengifo, Carlos

    2014-01-01

    This dissertation explores the pre-Columbian occupation at Cerro Castillo, a coastal settlement in the Nepeña Valley, Peru. The study examines the site’s internal organisation as well as its relationship with regional cultural phenomena during its most important period of occupation (circa AD 600-1000). Characterising the Moche presence at the site is one of the main subjects of this investigation. Moche was one of the grandest civilisations that developed in the pre-Columbian ...

  1. 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.

  2. Report about drilling works made in 13 Anomaly de Taylor and in the N- NE of its, around Fraile Muerto (Cerro Largo district): Uranium project

    International Nuclear Information System (INIS)

    The perforations were carried out to investigate in depth denominated anomaly 13 detected during the Taylor Mission (1975) and extended the punch area of study during you are suitable DINAMIGE-BRGM (Project the present report details the activities realised in the environs Fraile Muerto (Cerro Largo district) by the command team of perforations of the uranium project. Previously and contemporarily to the executed works, prospection became geophysical ground geochemistry geology and, works. (Uranium)

  3. Geothermal Reservoir Well Stimulation Project: reservoir selection task

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-01

    The Geothermal Reservoir Well Stimulation Project has prepared a two-year program to develop and field test methods of stimulating geothermal wells. The program provides for six field experiments which progress in difficulty from low temperature reservoirs using current technology to high temperature reservoirs using advanced types of stimulation treatments. The process used to select the six field experiment locations and stimulation treatments is described. Tentatively, the following reservoirs are proposed: Raft River, East Mesa, Baca and Westmorland (two experiments), and Brawley and The Geysers or Roosevelt Hot Springs (two experiments). The program will be reviewed after each field treatment to select a specific well candidate for the next experiment and to determine whether alteration of the sequence will be beneficial to the overall success of the project and the geothermal industry.

  4. 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

  5. Análisis litoestratigráfico de la Formación Cerro Azul (Mioceno Superior en la provincia de La Pampa

    Directory of Open Access Journals (Sweden)

    Graciela Visconti

    2010-10-01

    Full Text Available La Formación Cerro Azul fue definida en 1980 para incluir a las sedimentitas continentales pliocenas (limolitas arenosas y areniscas limosas que afloran de manera discontinua en casi todo el ámbito de la provincia de La Pampa. No obstante, varias investigaciones paleontológicas realizadas a partir de la segunda mitad de la década del 80' han permitido ubicar geocronológicamente a la unidad en el intervalo 10 Ma a 5,8-5,7 Ma. El objetivo del trabajo es realizar un análisis de las características litoestratigráficas de la Formación Cerro Azul de acuerdo al Código Argentino de Estratigrafía. Se propone un lectoestratotipo para la unidad, consistente en el perfil de Algarrobo del Águila y un perfil auxiliar en cerro El Morro. También se establecieron las relaciones estratigráficas con otras formaciones. Se interpreta un paleoambiente depositacional de llanura, donde alternan depósitos de loess con numerosos paleosuelos, detectándose escasos depósitos lacustres en la base y pocos cursos fluviales.

  6. Estimation of Bank Erosion Due To Reservoir Operation in Cascade (Case Study: Citarum Cascade Reservoir)

    OpenAIRE

    Sri Legowo; Iwan. K. Hadihardaja; Azmeri

    2009-01-01

    Sedimentation is such a crucial issue to be noted once the accumulated sediment begins to fill the reservoir dead storage, this will then influence the long-term reservoir operation. The sediment accumulated requires a serious attention for it may influence the storage capacity and other reservoir management of activities. The continuous inflow of sediment to the reservoir will decrease the capacity of reservoir storage, the reservoir value in use, and the useful age of reservoir. Because of ...

  7. 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

  8. Estructura, composición y diversidad de la selva baja caducifolia del Cerro Verde, Nizanda (Oaxaca, México

    Directory of Open Access Journals (Sweden)

    José Antonio Gallardo Cruz

    2005-01-01

    Full Text Available En este estudio se describe la estructura, la composición florística y los patrones de diversidad de la selva baja caducifolia del Cerro Verde, localizado en Nizanda (Istmo de Tehuantepec, Oaxaca, México. En 30 parcelas de 100 m2 se censaron las plantas leñosas con DAP ≥ 1 cm (estrato alto, y en cinco subcuadros de 4 m2 dentro de cada una se censaron las plantas con DAP 30 cm (estrato bajo. Se encontraron 194 especies distribuidas en 52 familias. La riqueza de especies fue idéntica en ambos estratos (145 especies, y cada uno aportó de manera exclusiva ca. 25% de la riqueza total registrada. Leguminosae fue la familia más rica en especies (27, seguida por Asteraceae (20 y Euphorbiaceae (18. Las especies más frecuentes fueron Bursera simaruba + B. aff. cinerea (no distinguidas en el campo, Euphorbia schlechtendalii, Pilosocereus collinsii y Capparis verrucosa. La riqueza específica promedio por cuadro fue de 30 especies. Los índices basados en la riqueza y la abundancia de las especies (Berger-Parker = 0.20; Simpson = 0.09; α de Fisher = 9.47; Shannon = 2.78; equitatividad = 0.82 indican una alta diversidad y una consecuente baja dominancia en esta selva. Los valores extrapolados mostraron una densidad total (estratos alto + bajo de 23,950 ind. ha-1 (830 ind. ha-1 con DAP ≥ 10 cm, una cobertura de 446.7%, y un área basal de 53 m2 ha-1. La altura promedio del 10% de los árboles más altos fue 9.1 m. La estructura de la selva baja del Cerro Verde es semejante a la de otras comunidades vegetales del trópico seco de México y denota un buen estado de conservación. Este hecho, aunado a su particular composición florística, enfatiza la pertinencia de su conservación formal.

  9. 2010 Fresno Reservoir Sedimentation Survey

    Data.gov (United States)

    US Bureau of Reclamation, Department of the Interior — The Bureau of Reclamation (Reclamation) surveyed Fresno Reservoir in June of 2010 to develop a topographic map and compute a storage-elevation relationship...

  10. 2011 Groundhog Reservoir Bathymetric Contours

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey performed a bathymetric survey of Groundhog Reservoir using a man-operated boat-mounted multibeam echo sounder integrated with a global...

  11. Glendo Reservoir 2003 Sedimenation Survey

    Data.gov (United States)

    US Bureau of Reclamation, Department of the Interior — The Bureau of Reclamation (Reclamation) surveyed Glendo Reservoir in May and July of 2003 and January 2005 to develop a new topographic map and compute a present...

  12. Reasons for reservoir effect variability

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2013-01-01

    Freshwater reservoir effects can be large and highly variable. I will present my investigations into the short-term variability of the freshwater reservoir effect in two Northern German rivers. The samples analysed in this study were collected between 2007 and 2012. Reservoir ages of water sample...... potentially very different radiocarbon ages. Finally, I will discuss the influence of bomb carbon on radiocarbon dating of modern freshwater samples....... plants. Their carbon should represent an average value of the entire growth season. However, there are large reservoir age variations in aquatic plants and animals as well. These can best be explained by the multitude of carbon sources which can be utilized by aquatic organisms, and which have...

  13. Fully analogue photonic reservoir computer

    Science.gov (United States)

    Duport, François; Smerieri, Anteo; Akrout, Akram; Haelterman, Marc; Massar, Serge

    2016-03-01

    Introduced a decade ago, reservoir computing is an efficient approach for signal processing. State of the art capabilities have already been demonstrated with both computer simulations and physical implementations. If photonic reservoir computing appears to be promising a solution for ultrafast nontrivial computing, all the implementations presented up to now require digital pre or post processing, which prevents them from exploiting their full potential, in particular in terms of processing speed. We address here the possibility to get rid simultaneously of both digital pre and post processing. The standalone fully analogue reservoir computer resulting from our endeavour is compared to previous experiments and only exhibits rather limited degradation of performances. Our experiment constitutes a proof of concept for standalone physical reservoir computers.

  14. Reservoir Interactions and Disease Emergence

    OpenAIRE

    Reluga, T.; Meza, R; Walton, D. B.; Galvani, A P

    2007-01-01

    Animal populations act as reservoirs for emerging diseases. In order for transmission to be self-sustaining, a pathogen must have a basic reproduction number R0 > 1. Following a founding transmission event from an animal reservoir to humans, a pathogen has not yet adapted to its new environment and is likely to have an R0 < 1. However, subsequent evolution may rescue the pathogen from extinction in its new host. Recent applications of branching process theory investigate how the emergence of ...

  15. Chickamauga reservoir embayment study - 1990

    Energy Technology Data Exchange (ETDEWEB)

    Meinert, D.L.; Butkus, S.R.; McDonough, T.A.

    1992-12-01

    The objectives of this report are three-fold: (1) assess physical, chemical, and biological conditions in the major embayments of Chickamauga Reservoir; (2) compare water quality and biological conditions of embayments with main river locations; and (3) identify any water quality concerns in the study embayments that may warrant further investigation and/or management actions. Embayments are important areas of reservoirs to be considered when assessments are made to support water quality management plans. In general, embayments, because of their smaller size (water surface areas usually less than 1000 acres), shallower morphometry (average depth usually less than 10 feet), and longer detention times (frequently a month or more), exhibit more extreme responses to pollutant loadings and changes in land use than the main river region of the reservoir. Consequently, embayments are often at greater risk of water quality impairments (e.g. nutrient enrichment, filling and siltation, excessive growths of aquatic plants, algal blooms, low dissolved oxygen concentrations, bacteriological contamination, etc.). Much of the secondary beneficial use of reservoirs occurs in embayments (viz. marinas, recreation areas, parks and beaches, residential development, etc.). Typically embayments comprise less than 20 percent of the surface area of a reservoir, but they often receive 50 percent or more of the water-oriented recreational use of the reservoir. This intensive recreational use creates a potential for adverse use impacts if poor water quality and aquatic conditions exist in an embayment.

  16. Capacity sharing of water reservoirs

    Science.gov (United States)

    Dudley, Norman J.; Musgrave, Warren F.

    1988-05-01

    The concept of a water use property right is developed which does not apply to water volumes as such but to a share of the capacity (not contents) of river storage reservoirs and their inflows. The shareholders can withdraw water from their share over time in accordance with their preferences for stability of water deliveries. The reservoir authority does not manage reservoir releases but keeps record of individual shareholder's withdrawals and net inflows to monitor the quantity of water in each shareholder's capacity share. A surplus of total reservoir contents over the sum of the contents of the individual shareholder's capacity shares will accrue over time. Two different criteria for its periodic distribution among shareholders are compared. A previous paper Dudley (this issue(b)) noted a loss of short-run economic efficiency as reservoir and farm management decision making become separated. This is largely overcome by capacity sharing which allows each user to integrate the management of their portion of the reservoir and their farming operations. The nonattenuated nature of the capacity sharing water rights also promotes long-run economic efficiency.

  17. Reservoir characterization of Pennsylvanian Sandstone Reservoirs. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1992-09-01

    This annual report describes the progress during the second year of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description and scale-up procedures; (ii) outcrop investigation; (iii) in-fill drilling potential. The first section describes the methods by which a reservoir can be characterized, can be described in three dimensions, and can be scaled up with respect to its properties, appropriate for simulation purposes. The second section describes the progress on investigation of an outcrop. The outcrop is an analog of Bartlesville Sandstone. We have drilled ten wells behind the outcrop and collected extensive log and core data. The cores have been slabbed, photographed and the several plugs have been taken. In addition, minipermeameter is used to measure permeabilities on the core surface at six inch intervals. The plugs have been analyzed for the permeability and porosity values. The variations in property values will be tied to the geological descriptions as well as the subsurface data collected from the Glen Pool field. The third section discusses the application of geostatistical techniques to infer in-fill well locations. The geostatistical technique used is the simulated annealing technique because of its flexibility. One of the important reservoir data is the production data. Use of production data will allow us to define the reservoir continuities, which may in turn, determine the in-fill well locations. The proposed technique allows us to incorporate some of the production data as constraints in the reservoir descriptions. The technique has been validated by comparing the results with numerical simulations.

  18. Remotely sensed small reservoir monitoring

    Science.gov (United States)

    Eilander, Dirk; Annor, Frank; Iannini, Lorenzo; van de Giesen, Nick

    2013-04-01

    A new 'growing' maximum likelihood classification algorithm for small reservoir delineation has been developed and is tested with Radarsat-2 data for reservoirs in the semi-arid Upper East Region, Ghana. The delineation algorithm is able to find the land-water boundary from SAR imagery for different weather and environmental conditions. As such, the algorithm allows for remote sensed operational monitoring of small reservoirs. Multipurpose small reservoirs (1-100 ha) are important for many livelihoods in rural semi-arid West Africa. In order to manage and plan these reservoirs and to assess their hydrological impact at a river basin scale, it is important to monitor their water storage fluctuation. Several studies on remotely sensed reservoir mapping have recently been published, but no single method yields good results for all weather and environmental conditions. Detection of small reservoirs from optical satellite imagery using supervised maximum likelihood classification is a well proved method. The application of this method for the monitoring of small reservoirs is however limited because of its dependence on cloud-free day-acquisitions. Delineation from SAR images is promising, but because of difficulties with wind induced Bragg-scattering and low contrast between the water surface and the dried-out surroundings at the end of the dry season, only quasi manual methods have been applied successfully. A smart combination of optical satellite based detection combined with a delineation method for SAR imagery is proposed. From the optical satellite based small reservoir detection the reservoir window is determined in which the 'growing' maximum likelihood classification on SAR images is performed. A water-class seed and land-class seed are implemented and grown dependent on the likelihood of a pixel to belong to one class. The likelihood is calculated based on the probability distributions of the growing land and water populations. Combinations of single

  19. 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.

  20. 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.

  1. Analysis of heavy oils: Method development and application to Cerro Negro heavy petroleum detailed separation and analysis of acidic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Green, J.B.; Yu, S.K.T.; Green, J.A.; Doughty, D.A.; Vogh, J.W.; Grigsby, R.D.

    1989-10-01

    An HPLC method for fractionation of whole acid concentrates into nominal compound class subfractions is described. The method utilizes silica columns and gradient elution with eluents containing a strong base, tetramethyl-ammonium hydroxide. The performance of the method is evaluated through analysis of subfractions obtained from a coal liquid, Wilmington, CA, petroleum and Cerro Negro heavy oil. Methods developed specifically for analysis of whole acid concentrates and subfractions are described in detail. These include: (1) an infrared method for determination of total hydroxyl and carboxyl groups after their conversion to trifluoroacetate and 2,2,2-trifluoresters, respectively. (2) an NMR method for functional group analysis based on methylation of acidic groups with {sup 13}C-enriched methyl iodide, (3) a nonaqueous titration procedure employing the potassium salt of dimethyl sulfoxide as a titrant for acidic compounds, (4) GC/MS analysis of hydroxyaromatic compounds after their conversion to trifluoroacetate esters, and (5) probe microdistillation high resolution mass spectrometric analysis of acid fractions exhibiting low volatility. 146 refs., 38 figs., 27 tabs.

  2. Late Quaternary vegetation, fire and climate history reconstructed from two cores at Cerro Toledo, Podocarpus National Park, southeastern Ecuadorian Andes

    Science.gov (United States)

    Brunschön, Corinna; Behling, Hermann

    2009-11-01

    The last ca. 20,000 yr of palaeoenvironmental conditions in Podocarpus National Park in the southeastern Ecuadorian Andes have been reconstructed from two pollen records from Cerro Toledo (04°22'28.6"S, 79°06'41.5"W) at 3150 m and 3110 m elevation. Páramo vegetation with high proportions of Plantago rigida characterised the last glacial maximum (LGM), reflecting cold and wet conditions. The upper forest line was at markedly lower elevations than present. After ca. 16,200 cal yr BP, páramo vegetation decreased slightly while mountain rainforest developed, suggesting rising temperatures. The trend of increasing temperatures and mountain rainforest expansion continued until ca. 8500 cal yr BP, while highest temperatures probably occurred from 9300 to 8500 cal yr BP. From ca. 8500 cal yr BP, páramo vegetation re-expanded with dominance of Poaceae, suggesting a change to cooler conditions. During the late Holocene after ca. 1800 cal yr BP, a decrease in páramo indicates a change to warmer conditions. Anthropogenic impact near the study site is indicated for times after 2300 cal yr BP. The regional environmental history indicates that through time the eastern Andean Cordillera in South Ecuador was influenced by eastern Amazonian climates rather than western Pacific climates.

  3. Material control and accountability (MC and A) recovery from the Cerro Grande fire at Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    During the week of May 10-14, 2000, the Cerro Grande Fire scorched over 40,000 acres of prime forestland and destroyed over 400 homes in the Los Alamos community and several structures at the Los Alamos National Laboratory (LANL). Of the land affected by the fire, nearly one quarter of it was Laboratory property. All of LANL's 64 material balance areas (MBAs) were affected to some degree, but one Category I technical area and several Category I11 and IV areas sustained heavy damage. When the MC and A personnel were allowed to return to work on May 23, they addressed the following problems: How do we assure both ourselves and the Department of Energy (DOE) that no nuclear materials had been compromised? How do we assist the nuclear material (NM) custodians and their operating groups so that they can resume normal MC and A operations? Immediately after the return to work, the Laboratory issued emergency MC and A assurance actions for Category I through Category IV facilities. We conducted special inventories, area walkthroughs, and other forms of evaluation so that within a month after the fire, we were able to release the last MBA to resume work and assure that all nuclear material had been accounted for. This paper discusses the measures LANL adopted to ensure that none of its nuclear material had been compromised.

  4. Estratigrafía y vertebrados (Aves y Mammalia de la Formación Cerro Bandera, Mioceno Temprano de la Provincia del Neuquén, Argentina Stratigraphy and vertebrates (Aves and Mammalia from the Cerro Bandera Formation, Early Miocene of Neuquén Province, Argentina

    Directory of Open Access Journals (Sweden)

    Alejandro Kramarz

    2005-07-01

    Full Text Available La Formación Cerro Bandera comprende una serie de pequeños afloramientos aislados, que conforman los relictos de un antiguo relleno aluvial desarrollado sobre pequeños valles locales. Se compone de una sucesión de depósitos piroclásticos reelaborados con intercalaciones de piroclastitas primarias y escasos niveles de areniscas. Estos depósitos fueron originalmente reconocidos en el extremo nordeste de la Barda Negra, sur de Cerro Bandera y noroeste de Sierra del Portezuelo; nuevos afloramientos son reconocidos aquí en la vertiente noroeste del cerro Bayo Mesa, Provincia del Neuquén, Argentina. Los restos fósiles exhumados corresponden a aves (Falconidae y mamíferos (17 familias, entre los que se destacan Cramauchenia normalis Ameghino, Proadinotherium cf. P. muensteri Ameghino, Eosteiromys sp. y Caviocricetus lucasi Vucetich y Verzi, junto con una especie de Protypotherium con dentadura más primitiva que las conocidas para la Edad Santacrucense. Esta asociación confirma una Edad Mamífero Colhuehuapense (Mioceno Temprano para esta unidad. La fauna exhibe marcadas diferencias con la registrada en la sección inferior de la Formación Chichinales, Provincia de Río Negro. El grado de diferenciación faunística entre estas dos unidades posiblemente sincrónicas podría obedecer a diferencias en los factores paleoambientales localesThe Cerro Bandera Formation comprises a series of isolated outcrops that represent the relicts of an old alluvial filling developed on small local valleys. It is composed of a succession of reworked pyroclastic deposits alternating with primary pyroclastic and scant sandstone levels. These deposits were originally recognized at the northeast of Barda Negra, south of Cerro Bandera and northwest of Sierra del Portezuelo; new exposures are herein recognised to the northwestern slope of Cerro Bayo Mesa, Neuquén Province, Argentina. The recovered fossil remains correspond to birds (Falconidae and 17 families of

  5. 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

    Directory of Open Access Journals (Sweden)

    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

  6. Reservoir Protection Technology in China: Research & Application

    Institute of Scientific and Technical Information of China (English)

    Li Qiangui; Wu Juan; Kang Yili

    2006-01-01

    @@ Great development of reservoir protection technology (RPT) has been achieved since 1996, including oil and gas reservoir protection for exploration wells, reservoir protection during underbalanced drilling, protection of fractured tight sandstone gas reservoir, and reservoir protection while increase production and reconstructing, development and enhanced oil recovery (EOR) etc. It has stepped into a new situation with special features and advantage. These technical advancements marked that China's RTP have realized leaps from porous reservoirs to fractured reservoirs,from conventional medium-to-low permeability reservoirs to unconventional reservoirs, from oil and gas producers to exploration wells, and from application mainly in drilling and completion processes to application in stimulation,development, production and EOR processes.

  7. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)

    P. K. Pande

    1998-10-29

    Initial drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, must become a process of the past. Such efforts do not optimize reservoir development as they fail to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. These reservoirs are typically characterized by: o Large, discontinuous pay intervals o Vertical and lateral changes in reservoir properties o Low reservoir energy o High residual oil saturation o Low recovery efficiency

  8. Cloud computing and Reservoir project

    International Nuclear Information System (INIS)

    The support for complex services delivery is becoming a key point in current internet technology. Current trends in internet applications are characterized by on demand delivery of ever growing amounts of content. The future internet of services will have to deliver content intensive applications to users with quality of service and security guarantees. This paper describes the Reservoir project and the challenge of a reliable and effective delivery of services as utilities in a commercial scenario. It starts by analyzing the needs of a future infrastructure provider and introducing the key concept of a service oriented architecture that combines virtualisation-aware grid with grid-aware virtualisation, while being driven by business service management. This article will then focus on the benefits and the innovations derived from the Reservoir approach. Eventually, a high level view of Reservoir general architecture is illustrated.

  9. Miniature Reservoir Cathode: An Update

    Science.gov (United States)

    Vancil, Bernard K.; Wintucky, Edwin G.

    2002-01-01

    We report on recent work to produce a small low power, low cost reservoir cathode capable of long life (more than 100,000 hours) at high loading (> 5 A/sq cm). Our objective is a highly manufacturable, commercial device costing less than $30. Small highly loaded cathodes are needed, especially for millimeter wave tubes, where focusing becomes difficult when area convergence ratios are too high. We currently have 3 models ranging from .060-inch diameter to. 125-inch diameter. Reservoir type barium dispenser cathodes have a demonstrated capability for simultaneous high emission density and long life. Seven reservoir cathodes continue to operate on the cathode life test facility at NSWC, Crane, Indiana at 2 and 4 amps/sq cm. They have accumulated nearly 100,000 hours with practically no change in emission levels or knee temperature.

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

  11. Sedimentología y evolución paleoambiental de la Formación Patquía (Pérmico en el extremo sur de la sierra de Maz y cerro Bola, provincia de La Rioja, Argentina Sedimentology and palaeoenvironmental evolution of the Patquía Formation (Permian, in the Sierra de Maz and cerro Bola, La Rioja Province, Argentina

    Directory of Open Access Journals (Sweden)

    A. T. Caselli

    2002-12-01

    Full Text Available En este trabajo se analizan las características sedimentológicas de la Formación Patquía en la Sierra de Maz y en el Cerro Bola (perfiles de cerro Guandacol, La Cortadera, cerro Noqués y cerro Bola, donde fueron reconocidas siete asociaciones de facies. La facies A está compuesta por aglomerados, brechas y conglomerados depositados en pequeños abanicos aluviales. Areniscas gruesas y conglomerados integran la facies B, la que fue probablemente depositada en planicies fluviales entrelazadas. La facies C incluye conglomerados y areniscas gruesas correspondientes a sistemas fluviales de baja sinuosidad. La facies D es la más extendida regionalmente y está compuesta por sabulitas, areniscas, pelitas y tobas, interpretadas como cursos fluviales de elevada sinuosidad. Un episodio de sedimentación eólica está registrado en la facies E, constituida por areniscas finas a medianas mostrando estratificación entrecruzada de gran escala. La facies F, areniscas y pelitas interestratificadas, fue depositada en lagos clásticos, someros y permanentes. La facies G incluye areniscas blanquecinas y pelitas rosadas, con intercalaciones de areniscas finas con estratificación entrecruzada de gran escala, sedimentadas en sistemas fluviales sinuosos con migración de dunas eólicas en las planicies. La composición modal de las areniscas permite identificar tres petrofacies. La cuarzoféldica representa el aporte del basamento de las Sierras Pampeanas. La cuarzofeldlítica incluye fragmentos de volcanitas ácidas y mesosilícicas relacionadas a la faja volcánica Permo-Triásica ubicada al oeste. La litomíxtica está dominada por líticos sedimentarios y paleovolcánicos provenientes de la Precordillera. Finalmente, el análisis estratigráfico de las facies arriba descriptas permitió la identificación de dos secuencias depositacionales.The sedimentological characteristics of the Patquía Formation in the Sierra de Maz and Cerro Bola areas were analyzed

  12. The Carpenteria reservoir redevelopment project

    Energy Technology Data Exchange (ETDEWEB)

    Kendall, R.P.; Whitney, E.M.; Krogh, K.E. [Los Alamos National Lab., NM (United States); Coombs, S. [Pacific Operators Offshore, Inc., Carpinteria, CA (United States); Paul, R.G. [Dept. of the Interior (United States); Voskanian, M.M. [California State Lands Commission, Sacramento, CA (United States); Ershaghi, I. [University of Southern California, Los Angeles, CA (United States)

    1997-08-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to develop a simulation-based reservoir management system that could be used to guide the redevelopment of the Carpenteria Offshore Field, which is located just seven miles from Santa Barbara. The system supports geostatistical and geological modeling and reservoir forecasting. Moreover, it is also a shared resource between the field operator, Pacific Operators Offshore, and the mineral owners, the U.S. Department of the Interior and the State of California.

  13. Horizontal drilling in shallow reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Murray, W.F. Jr.; Schrider, L.A.; McCallister, J.V.; Mazza, R.L.

    1993-12-31

    Belden & Blake and the US DOE will cofund a horizontal well to be drilled in the Clinton Sandstone as part of the DOE`s multi well program titled ``Horizontal Drilling in Shallow Geologic Complex Reservoirs.`` This well will be located in Mahoning County, Ohio in an area which has demonstrated above average Clinton gas production. To the best of our knowledge, this will be the first horizontal well drilled to the Clinton Sand formation in Ohio. Since many of the remaining Clinton Sand drilling sites are of poorer reservoir quality, they may not be developed unless technology such as horizontal drilling can be successfully demonstrated.

  14. Columnar jointing in vapor-phase-altered, non-welded Cerro Galán Ignimbrite, Paycuqui, Argentina

    Science.gov (United States)

    Wright, Heather M.; Lesti, Chiara; Cas, Ray A.F.; Porreca, Massimiliano; Viramonte, Jose G.; Folkes, Christopher B.; Giordano, Guido

    2011-01-01

    Columnar jointing is thought to occur primarily in lavas and welded pyroclastic flow deposits. However, the non-welded Cerro Galán Ignimbrite at Paycuqui, Argentina, contains well-developed columnar joints that are instead due to high-temperature vapor-phase alteration of the deposit, where devitrification and vapor-phase crystallization have increased the density and cohesion of the upper half of the section. Thermal remanent magnetization analyses of entrained lithic clasts indicate high emplacement temperatures, above 630°C, but the lack of welding textures indicates temperatures below the glass transition temperature. In order to remain below the glass transition at 630°C, the minimum cooling rate prior to deposition was 3.0 × 10−3–8.5 × 10−2°C/min (depending on the experimental data used for comparison). Alternatively, if the deposit was emplaced above the glass transition temperature, conductive cooling alone was insufficient to prevent welding. Crack patterns (average, 4.5 sides to each polygon) and column diameters (average, 75 cm) are consistent with relatively rapid cooling, where advective heat loss due to vapor fluxing increases cooling over simple conductive heat transfer. The presence of regularly spaced, complex radiating joint patterns is consistent with fumarolic gas rise, where volatiles originated in the valley-confined drainage system below. Joint spacing is a proxy for cooling rates and is controlled by depositional thickness/valley width. We suggest that the formation of joints in high-temperature, non-welded deposits is aided by the presence of underlying external water, where vapor transfer causes crystallization in pore spaces, densifies the deposit, and helps prevent welding.

  15. Columnar jointing in vapor-phase-altered, non-welded Cerro Galán Ignimbrite, Paycuqui, Argentina

    Science.gov (United States)

    Wright, Heather M. N.; Lesti, Chiara; Cas, Raymond A. F.; Porreca, Massimiliano; Viramonte, José G.; Folkes, Chris B.; Giordano, Guido

    2011-12-01

    Columnar jointing is thought to occur primarily in lavas and welded pyroclastic flow deposits. However, the non-welded Cerro Galán Ignimbrite at Paycuqui, Argentina, contains well-developed columnar joints that are instead due to high-temperature vapor-phase alteration of the deposit, where devitrification and vapor-phase crystallization have increased the density and cohesion of the upper half of the section. Thermal remanent magnetization analyses of entrained lithic clasts indicate high emplacement temperatures, above 630°C, but the lack of welding textures indicates temperatures below the glass transition temperature. In order to remain below the glass transition at 630°C, the minimum cooling rate prior to deposition was 3.0 × 10-3-8.5 × 10-2°C/min (depending on the experimental data used for comparison). Alternatively, if the deposit was emplaced above the glass transition temperature, conductive cooling alone was insufficient to prevent welding. Crack patterns (average, 4.5 sides to each polygon) and column diameters (average, 75 cm) are consistent with relatively rapid cooling, where advective heat loss due to vapor fluxing increases cooling over simple conductive heat transfer. The presence of regularly spaced, complex radiating joint patterns is consistent with fumarolic gas rise, where volatiles originated in the valley-confined drainage system below. Joint spacing is a proxy for cooling rates and is controlled by depositional thickness/valley width. We suggest that the formation of joints in high-temperature, non-welded deposits is aided by the presence of underlying external water, where vapor transfer causes crystallization in pore spaces, densifies the deposit, and helps prevent welding.

  16. Perfil infectológico de poblaciones mapuche de Cerro Policía y Aguada Guzmán de la provincia de Río Negro

    OpenAIRE

    Rey, Jorge Alberto; Dejean, Cristina Beatriz; Niborski, Ricardo; Arrayago, Alicia M.; Kohan, Abraham I.; Carnese, Francisco R.

    1996-01-01

    Nuestro trabajo analiza la prevalencia de marcadores de algunas infecciones que afectan las poblaciones mapuche de Cerro Policía (CP) y Aguada Guzmán (AG) en la Prov. de Río Negro. Los estudios incluídos son: determinación de anticuerpos anti-Treponema pallidum, anti-Trypanosoma cruzii, anti-Echinococcus granulosus, antígeno de superficie de la Hepatitis B (HBsAg), anticuerpos contra el core de la Hepatitis B (anti-HBc), anticuerpos contra el virus de la Hepatitis A (anti-HAV). Se estudiaron ...

  17. NUEVOS APORTES AL CONOCIMIENTO DE LA HERPETOFAUNA DE LA FORMACIÓN CERRO AZUL (MIOCENO SUPERIOR), PROVINCIA DE LA PAMPA, ARGENTINA

    OpenAIRE

    AGUSTÍN SCANFERLA; Agnolín, Federico L.

    2015-01-01

    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 a...

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

    OpenAIRE

    Mariano Bonomo; Juan Carlos Castro; Carolina Belén Silva

    2014-01-01

    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 rem...

  19. Apresentacão do Projeto de extensão universitaria "Fortalecimento das Capacidades das Educadoras do Programa CAIF no estado de Cerro Largo-Uruguai"

    OpenAIRE

    Mariana Porta Galván

    2015-01-01

    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 pol...

  20. Dos tumbas de Época Altoimperial documentadas en el entorno minero de Cerro Muriano (Córdoba): I.A.U. La Mocha

    OpenAIRE

    Moreno Garrido, María Jesús; Penco Valenzuela, Fernando

    2000-01-01

    The last archaeological explorations and other researches made at Cerro Muria­no come to corroborate the importance of this mining whole wich, according to all the vestiges, was already worked during Prehistory. Lower down, we show some outstanding aspects about two burials excavated on geological rock that must be produced about the transition from I B.C. to I A.C. century. Constitute the first two examples of funeral structures wich have been verified in this space, that has been continousl...

  1. Dispersión de semillas por murciélagos frugívoros en bosques del Parque Nacional Cerros de Amotape, Tumbes, Perú

    OpenAIRE

    Sidney Novoa; Richard Cadenillas; Víctor Pacheco

    2011-01-01

    Se evaluó el rol de los murciélagos frugívoros como dispersores de semillas en tres tipos de hábitat del Parque Nacional Cerros de Amotape, Tumbes, Perú. Se analizó la dieta identificando y cuantificando las semillas encontradas en muestras fecales. Se interpreta la preferencia por los recursos vegetales, amplitud de nicho, la importancia de cada especie como dispersora y el nivel de solapamiento de nicho trófico. Se capturaron 33 especies de murciélagos, de las cuales 13 fueron predominantem...

  2. Nechako Reservoir mathematical modelling studies

    International Nuclear Information System (INIS)

    The addition of 540 MW of hydroelectric generating capacity to the Nechako Reservoir involves the increased diversion of water from the headwaters of the Nechako River in the Fraser River drainage to the Kemano River on the Pacific coast. Approval of the project requires a two level release structure at Kenney Dam at the head of the Nechako Canyon to manage downstream flows and water temperatures to conserve and protect chinook and sockeye populations. Two- and three-dimensional mathematical models were used to evaluate the hydrothermal characteristics of the Nechako Reservoir and to assess the capability of the proposed structure to provide releases necessary to meet downstream objectives. Results of the modelling show that deep water intake temperatures are sensitive to reservoir surface elevation and the deep water intake elevation. Modelling results for maximum release of 200 m3/s show that the deep water intake invert should be located at an elevation of 795 m to ensure water temperature criteria are met. The three dimensional modelling showed that little, if any additional bottom water mixing beyond that indicated by the two dimensional results for a nearby lake is likely to occur as a result of the Kenamo completion project. Extreme condition analysis shows that there exists sufficient volumes of cold water in the Nechako reservoir to ensure that the 10 degree C water release criteria can be met for the required period. 4 refs., 1 fig

  3. Mathematical modelling of reservoir ecosystems

    Czech Academy of Sciences Publication Activity Database

    Růžička, Martin; Hejzlar, Josef; Kafková, Dagmar; Balejová, Marcela; Thébault, J. M.

    2001-01-01

    Roč. 49, č. 2 (2001), s. 109-124. ISSN 0042-790X R&D Projects: GA ČR GA103/98/0281; GA AV ČR IAA3042903 Keywords : mathematical model ling * ecosystems * reservoir Rimov Subject RIV: BK - Fluid Dynamics

  4. Reservoir Cathode for Electric Space Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a hollow reservoir cathode to improve performance in ion and Hall thrusters. We will adapt our existing reservoir cathode technology to this purpose....

  5. Reservoir Cathode for Electric Space Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a reservoir cathode to improve performance in both ion and Hall-effect thrusters. We propose to adapt our existing reservoir cathode technology to this...

  6. Integrated reservoir management -- a team approach

    International Nuclear Information System (INIS)

    Integrated reservoir management has received significant attention in recent years. The need to enhance recovery from the vast amount of remaining oil- and gas-in-place requires better reservoir management practices. The purpose of this article is to outline critical technical areas, document benefits received from a team approach to reservoir management, and identify the major attributes of a successful reservoir management organization and program

  7. Generation of entanglement density within a reservoir

    OpenAIRE

    Lazarou, C.; Garraway, B. M.; Piilo, J.; Maniscalco, S.

    2011-01-01

    Abstract We study a single two-level atom interacting with a reservoir of modes defined by its reservoir structure function. Within this framework we are able to define a density of entanglement involving a continuum of reservoir modes. The density of entanglement is derived for a system with a single excitation by taking a limit of the global entanglement. Utilizing the density of entanglement we quantify the entanglement between the atom and the modes, and also between the reservoir mode...

  8. Stretch due to Penile Prosthesis Reservoir Migration

    OpenAIRE

    Baten, E.; Vandewalle, T.; van Renterghem, K.

    2016-01-01

    A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely ra...

  9. Caracterización detallada de la mineralización en veta Eureka, y su comparación con otras mineralizaciones del Distrito Cerro Negro, Macizo del Deseado, Santa Cruz, Argentina

    OpenAIRE

    Permuy Vidal, Conrado

    2014-01-01

    El distrito Cerro Negro está ubicado en el noroeste del Macizo del Deseado, a unos 50 km al sureste de la localidad de Perito Moreno, en la provincia de Santa Cruz (Patagonia, Argentina). Comprende un conjunto de mineralizaciones vetiformes epitermales de Au-Ag con reservas calculadas en 6,7 Moz Au eq., que posicionan actualmente a Cerro Negro como el más importante proyecto epitermal de oro y plata de la región y como uno de los más importantes descubrimientos epitermales a nivel mundial. En...

  10. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    International Nuclear Information System (INIS)

    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir’s layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir’s character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia

  11. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Nurhandoko, Bagus Endar B., E-mail: bagusnur@bdg.centrin.net.id, E-mail: bagusnur@rock-fluid.com [Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Basic Science Center A 4" t" hfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia); Susilowati, E-mail: bagusnur@bdg.centrin.net.id, E-mail: bagusnur@rock-fluid.com [Rock Fluid Imaging Lab., Bandung (Indonesia)

    2015-04-16

    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir’s layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir’s character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia.

  12. Tenth workshop on geothermal reservoir engineering: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-22

    The workshop contains presentations in the following areas: (1) reservoir engineering research; (2) field development; (3) vapor-dominated systems; (4) the Geysers thermal area; (5) well test analysis; (6) production engineering; (7) reservoir evaluation; (8) geochemistry and injection; (9) numerical simulation; and (10) reservoir physics. (ACR)

  13. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Roy; Clarke, Don; Walker, Scott; Phillips, Chris; Nguyen, John; Moos, Dan; Tagbor, Kwasi

    2001-08-07

    This project was intended to increase recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs, transferring technology so that it can be applied in other sections of the Wilmington field and by operators in other slope and basin reservoirs is a primary component of the project.

  14. Hydropower plant Ermenek. Reservoir impounding; Wasserkraftanlage Ermenek. Einstau des Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Linortner, Johannes [Poeyry Energy Turkey, Ankara (Turkey); Zenz, Gerald [Graz Univ. of Technology (Austria); Kohler, Roman [Poeyry Energy Austria, Salzburg (Austria)

    2010-07-01

    A Turkish-Austrian Consortium is constructing the hydro power plant Ermenek in Turkey. Client of this project is the Turkish State Hydraulic Works, DSI. The project consists of a double curved arch dam, a large grout curtain, a pressure tunnel, a power house and appurtenant structures. The arch dam is ideally located in a narrow gorge, with a natural width at the base of 20 m and at the crest of 110 m, with an entire dam height of 218 m and a concrete volume of 290 000 m{sup 3}. The concreting works for the dam started on 6{sup th} September 2007 and were finished by 20{sup th} October 2009. As the reservoir has an overall volume of about 4 600 million m{sup 3} the impounding started during the construction. Within a very short time the reservoir level has increased up to 70 m above foundation. The entire dam safety concept is discussed. (orig.)

  15. Structure of the Wagner Basin in the Northern Gulf of California From Interpretation of Seismic Reflexion Data

    Science.gov (United States)

    Gonzalez, M.; Aguilar, C.; Martin, A.

    2007-05-01

    The northern Gulf of California straddles the transition in the style of deformation along the Pacific-North America plate boundary, from distributed deformation in the Upper Delfin and Wagner basins to localized dextral shear along the Cerro Prieto transform fault. Processing and interpretation of industry seismic data adquired by Petroleos Mexicanos (PEMEX) allow us to map the main fault structures and depocenters in the Wagner basin and to unravel the way strain is transferred northward into the Cerro Prieto fault system. Seismic data records from 0.5 to 5 TWTT. Data stacking and time-migration were performed using semblance coefficient method. Subsidence in the Wagner basin is controlled by two large N-S trending sub-parallel faults that intersect the NNW-trending Cerro Prieto transform fault. The Wagner fault bounds the eastern margin of the basin for more than 75 km. This fault dips ~50° to the west (up to 2 seconds) with distinctive reflectors displaced more than 1 km across the fault zone. The strata define a fanning pattern towards the Wagner fault. Northward the Wagner fault intersects the Cerro Prieto fault at 130° on map view and one depocenter of the Wagner basin bends to the NW adjacent to the Cerro Prieto fault zone. The eastern boundary of the modern depocenter is the Consag fault, which extends over 100 km in a N-S direction with an average dip of ~50° (up to 2s) to the east. The northern segment of the Consag fault bends 25° and intersects the Cerro Prieto fault zone at an angle of 110° on map view. The acoustic basement was not imaged in the northwest, but the stratigraphic succession increases its thickness towards the depocenter of the Wagner basin. Another important structure is El Chinero fault, which runs parallel to the Consag fault along 60 km and possibly intersects the Cerro Prieto fault to the north beneath the delta of the Colorado River. El Chinero fault dips at low-angle (~30°) to the east and has a vertical offset of about 0

  16. ANALISIS DEL CO-TRATAMIENTO PASIVO DE AGUAS RESIDUALES MUNICIPALES Y DRENAJE ACIDO DE MINAS EN CERRO RICO DE POTOSÍ, BOLIVIA

    Directory of Open Access Journals (Sweden)

    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.

  17. Enterramiento colectivo y metalurgia en el yacimiento Neolítico de Cerro Virtud (Cuevas de Almanzora, Almería

    Directory of Open Access Journals (Sweden)

    Montero Ruiz, Ignacio

    1996-12-01

    Full Text Available The rescue excavation of the Cerro Virtud (Almería, Spain, has shown new evidences that might change the traditional interpretations of the Neolithic period. This excavation has documented not only the first burials associated with an open air site but also pristine metallurgical activity within a Neolithic context. When first employed by archaeologists, the term ''Neolithic" implied a thechnological rather than an economic phenomenon. In this article we shall discuss the terminological implications of metal in order to understand the development of Neolithic in the Iberian Peninsula.

    La excavación de urgencia de Cerro Virtud (Almería, España ha documentado nuevos datos que permiten cambiar algunas de las interpretaciones tradicionales sobre el Neolítico. La aparición de un enterramiento colectivo en un yacimiento al aire libre, así como las primeras evidencias de actividad metalúrgica en contexto neolítico son las principales novedades. Se discuten las implicaciones que la aparición del metal supone para comprender el desarrollo del Neolítico en la Península Ibérica, teniendo en cuenta la fuerte carga tecnológica que predomina en el uso de ese término "Neolítico".

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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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., III; 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.

  20. 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

  1. The ~ 2500 yr B.P. Chicoral non-cohesive debris flow from Cerro Machín Volcano, Colombia

    Science.gov (United States)

    Murcia, H. F.; Hurtado, B. O.; Cortés, G. P.; Macías, J. L.; Cepeda, H.

    2008-04-01

    Cerro Machín Volcano (CMV) is located in the central part of the Colombian Andes (2750 m asl), 150 km southwest of Bogotá. It is considered the most dangerous active volcano of Colombia. CMV has experienced at least six major explosive eruptions during the last 5000 years. These eruptions have emplaced many types of pyroclastic deposits with associated lahars that have traveled more than 100 km. One of these lahars is called Chicoral Debris Flow Deposit (DFD2). This deposit is exposed as discontinuous terraces (3-20 m thick) along the Coello and Magdalena rivers up to 109 km from the source. The DFD2 covers a minimum area of 62 km 2 and has a minimum volume of 0.57 km 3. It comprises two dacite-rich volcaniclastic units. Grain-size analysis reveals that the matrix content and sorting increase with distance while the average grain size decreases. The clay content of the DFD2 matrix is approximately 1%, thus categorizing it as a non-cohesive debris flow. Radiocarbon dates obtained from underlying and overlying paleosols yielded ages of 2505 + 65 and 1640 + 45 yr B.P., respectively. These dates suggest that DFD2 is related to the ~ 2600 yr B.P. El Guaico eruption of CMV. This eruption produced a block-and-ash flow that filled and blocked the Toche River up to 5 km from the volcano. Subsequent remobilization of this loose material by runoff water generated a massive debris flow that traveled 91 km along the Toche and Coello rivers and continued across the Espinal Alluvial Fan debouching into the Magdalena River where it continued another 18 km prior to its transformation into a sediment-laden flow. Because the last eruption of the volcano occurred ca. 900 years ago, no historic activity of CMV is known among inhabitants of the region. Hence the region has developed without awareness of volcanic hazards. Therefore an assessment of volcanic hazards is essential for understanding and evaluating the vulnerability and risk to which people are exposed in case of a future

  2. 4. International reservoir characterization technical conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    This volume contains the Proceedings of the Fourth International Reservoir Characterization Technical Conference held March 2-4, 1997 in Houston, Texas. The theme for the conference was Advances in Reservoir Characterization for Effective Reservoir Management. On March 2, 1997, the DOE Class Workshop kicked off with tutorials by Dr. Steve Begg (BP Exploration) and Dr. Ganesh Thakur (Chevron). Tutorial presentations are not included in these Proceedings but may be available from the authors. The conference consisted of the following topics: data acquisition; reservoir modeling; scaling reservoir properties; and managing uncertainty. Selected papers have been processed separately for inclusion in the Energy Science and Technology database.

  3. Statfjord field: Development strategy and reservoir management

    International Nuclear Information System (INIS)

    This paper reviews the reservoir performance and management of the Statfjord Field after eight years of production. The reason behind the reservoir development strategies and field experiences are presented. The original development plans have been refined based on field performance through an extensive monitoring program and use of reservoir simulation. The acquired data has improved the geological model and the knowledge of fluid movements in all three reservoirs. This has resulted in a large and complex reservoir simulation model with more than 20,000 grid blocks

  4. The role of reservoir characterization in the reservoir management process (as reflected in the Department of Energy`s reservoir management demonstration program)

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M.L. [BDM-Petroleum Technologies, Bartlesville, OK (United States); Young, M.A.; Madden, M.P. [BDM-Oklahoma, Bartlesville, OK (United States)] [and others

    1997-08-01

    Optimum reservoir recovery and profitability result from guidance of reservoir practices provided by an effective reservoir management plan. Success in developing the best, most appropriate reservoir management plan requires knowledge and consideration of (1) the reservoir system including rocks, and rock-fluid interactions (i.e., a characterization of the reservoir) as well as wellbores and associated equipment and surface facilities; (2) the technologies available to describe, analyze, and exploit the reservoir; and (3) the business environment under which the plan will be developed and implemented. Reservoir characterization is the essential to gain needed knowledge of the reservoir for reservoir management plan building. Reservoir characterization efforts can be appropriately scaled by considering the reservoir management context under which the plan is being built. Reservoir management plans de-optimize with time as technology and the business environment change or as new reservoir information indicates the reservoir characterization models on which the current plan is based are inadequate. BDM-Oklahoma and the Department of Energy have implemented a program of reservoir management demonstrations to encourage operators with limited resources and experience to learn, implement, and disperse sound reservoir management techniques through cooperative research and development projects whose objectives are to develop reservoir management plans. In each of the three projects currently underway, careful attention to reservoir management context assures a reservoir characterization approach that is sufficient, but not in excess of what is necessary, to devise and implement an effective reservoir management plan.

  5. Production Optimization of Oil Reservoirs

    DEFF Research Database (Denmark)

    Völcker, Carsten

    With an increasing demand for oil and diculties in nding new major oil elds, research on methods to improve oil recovery from existing elds is more necessary now than ever. The subject of this thesis is to construct ecient numerical methods for simulation and optimization of oil recovery with...... emphasis on optimal control of water ooding with the use of smartwell technology. We have implemented immiscible ow of water and oil in isothermal reservoirs with isotropic heterogenous permeability elds. We use the method of lines for solution of the partial differential equation (PDE) system that governs...... size control in order to minimize the computational cost per simulation. We implement a numerical method for nonlinear model predictive control (NMPC) along with smart-well technology to maximize the net present value (NPV) of an oil reservoir. The optimization is based on quasi-Newton sequential...

  6. Reservoir compartmentalization assessment by using FTIR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Permanyer, A. [Dept. Geoquimica, Petrologia i Prospeccio Geologica, Universitat de Barcelona, Marti i Franques, s/n, 08028 - Barcelona, Catalonia (Spain); Rebufa, C.; Kister, J. [Universite d' Aix - Marseille III, Faculte des Sciences et Techniques de St. Jerome, CNRS UMR 6171, Laboratoire de Geochimie Organique Analytique et Environnement (GOAE), Case 561, 13397 Marseille Cedex 20 (France)

    2007-09-15

    Reservoir geochemistry has traditionally used the gas chromatographic fingerprinting method and star diagrams to provide evidence of petroleum reservoir compartmentalization. Recently alternative techniques such as Fourier Transform Infra Red (FTIR) spectroscopy have been postulated to aid the evaluation of reservoir compartmentalization, and to characterize the geochemical evolution of oils from individual reservoirs. FTIR spectroscopy was applied successfully in the Tarragona Basin, Offshore N.E. Spain, validating the method to identify oils from different reservoirs. Moreover the method was successfully applied to provide evidence of compositional differences in oils from a faulted reservoir (El Furrial field, Venezuela), in which GC fingerprints failed to differentiate the oils. FTIR spectroscopy therefore, proves to be a complementary tool for reservoir compartmentalization studies. (author)

  7. Stocks Reservoir report June 1988

    OpenAIRE

    Walker, N.M.

    1988-01-01

    This report comprises a mean weekly summary of the raw data of the fish population of the Stocks Reservoir major tributaries in conjunction with completed maps, diagrams, tables and figures. These cover the Stocks tributary stream survey, the Fishery and fish plate impingement. This paper does not constitute a final report which the author intends to submit as a Ph.D. thesis. However, it does present much of the data and analysis completed in its final draft, which may be of immediate...

  8. Mathematical Optimization in Reservoir Management

    OpenAIRE

    Najafiazar, Bahador

    2014-01-01

    Getting the most out of a hydrocarbon reservoir is not a trivial task. It takes plentyof interwoven decisions to make. There are many forms of tools that support engineersto make correct decisions. The simplest ones would only display measurementsin a suitable way, and appoint the rest of the decision making processto human knowledge and experience. Complex decision support tools may implementmodel-based estimation and optimization. This work targets methods foroptimization-based decision sup...

  9. Carbon sequestration in leaky reservoirs

    OpenAIRE

    Jean-Marie, Alain; MOREAUX Michel; Tidball, Mabel

    2011-01-01

    PDF file identical to the paper submitted (available online at the conference site) with authors and affiliations added. International audience We propose in this paper a model of optimal Carbon Capture and Storage in which the reservoir of sequestered carbon is leaky, and pollution eventually is released into the atmosphere. We formulate the social planner problem as an optimal control program and we describe the optimal consumption paths as a function of the initial conditions, the ph...

  10. Reservoir characterization using wavelet transforms

    Science.gov (United States)

    Rivera Vega, Nestor

    Automated detection of geological boundaries and determination of cyclic events controlling deposition can facilitate stratigraphic analysis and reservoir characterization. This study applies the wavelet transformation, a recent advance in signal analysis techniques, to interpret cyclicity, determine its controlling factors, and detect zone boundaries. We tested the cyclostratigraphic assessments using well log and core data from a well in a fluvio-eolian sequence in the Ormskirk Sandstone, Irish Sea. The boundary detection technique was tested using log data from 10 wells in the Apiay field, Colombia. We processed the wavelet coefficients for each zone of the Ormskirk Formation and determined the wavelengths of the strongest cyclicities. Comparing these periodicities with Milankovitch cycles, we found a strong correspondence of the two. This suggests that climate exercised an important control on depositional cyclicity, as had been concluded in previous studies of the Ormskirk Sandstone. The wavelet coefficients from the log data in the Apiay field were combined to form features. These vectors were used in conjunction with pattern recognition techniques to perform detection in 7 boundaries. For the upper two units, the boundary was detected within 10 feet of their actual depth, in 90% of the wells. The mean detection performance in the Apiay field is 50%. We compared our method with other traditional techniques which do not focus on selecting optimal features for boundary identification. Those methods resulted in detection performances of 40% for the uppermost boundary, which lag behind the 90% performance of our method. Automated determination of geologic boundaries will expedite studies, and knowledge of the controlling deposition factors will enhance stratigraphic and reservoir characterization models. We expect that automated boundary detection and cyclicity analysis will prove to be valuable and time-saving methods for establishing correlations and their

  11. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  12. Estudio petrográfico de las facies piroclásticas de la Formación Cerro Varela en el sur de la Sierra de San Luis

    Directory of Open Access Journals (Sweden)

    Amancay N. Martínez

    2010-11-01

    Full Text Available En la provincia de San Luis, existen tres sub-cuencas denominadas Las Salinas, Beazley y Mercedes. Estas cuencas corresponden a depocentros de rift elongados en sentido NO, que alojan rocas ígneas de edad triásica con espesores que llegan hasta los 4.000 metros. Las rocas ígneas de la Formación Cerro Varela forman parte del cerro homónimo que constituye los últimos asomos australes de la sierra de San Luis. Las riolitas triásicas que afloran en la sierra de Varela se disponen dentro de un esquema estructural extensional asociado a la formación de cuencas de tipo rift. Las unidades analizadas de la Formación Cerro Varela están compuestas por tobas cristalinas tanto de alto grado como de bajo grado de soldadura, de composición riolítica e interpretadas como depósitos originados por flujos piroclásticos. Por su litología, edad y contexto regional, las rocas de la Formación Cerro Varela integran el magmatismo gondwánico del Grupo Choiyoi de edad permotriásica de la Cordillera Frontal de Mendoza y San Juan.

  13. 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

    Directory of Open Access Journals (Sweden)

    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

  14. Reservoir evaluation using discriminant analysis. [China

    Energy Technology Data Exchange (ETDEWEB)

    Yangjian, O.; Jianru, L.

    1982-01-01

    The ability to evaluate sandstone reservoirs has been greatly improved since the use of electonic computer in processing well log data. But it is still difficult to analyse reservoirs with high water saturation, or reservoirs with high residual oil saturation and aquifers containing oil etc. Based on the studies of the reservoirs and aquifers in respect to their oil saturation, porosity, lithology factor and other independent parameters relative to water invasion and water distribution etc., an optimum discrimination is proposed for the accurate evalation of reservoirs and aquifers using discriminant analysis as a tool. The final recognition is achieved on the electronic computer. This new technique and processing program has been widely tested and verified in the Shengli oil field and other fields in east China, with precision up to 90 percent or more. Now the technique has been extensively applied to the evaluation of Tertiary reservoirs with success.

  15. Data Compression of Hydrocarbon Reservoir Simulation Grids

    KAUST Repository

    Chavez, Gustavo Ivan

    2015-05-28

    A dense volumetric grid coming from an oil/gas reservoir simulation output is translated into a compact representation that supports desired features such as interactive visualization, geometric continuity, color mapping and quad representation. A set of four control curves per layer results from processing the grid data, and a complete set of these 3-dimensional surfaces represents the complete volume data and can map reservoir properties of interest to analysts. The processing results yield a representation of reservoir simulation results which has reduced data storage requirements and permits quick performance interaction between reservoir analysts and the simulation data. The degree of reservoir grid compression can be selected according to the quality required, by adjusting for different thresholds, such as approximation error and level of detail. The processions results are of potential benefit in applications such as interactive rendering, data compression, and in-situ visualization of large-scale oil/gas reservoir simulations.

  16. 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

    Directory of Open Access Journals (Sweden)

    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

  17. 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

    OpenAIRE

    D. Mutti; S. González Chiozza

    2005-01-01

    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...

  18. 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).

    OpenAIRE

    María de los Milagros Colobig; Jorge Omar Sánchez; Alejandro Fabián Zucol

    2015-01-01

    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, ...

  19. CARACTERIZACIÓN FLORÍSTICA Y ESTRUCTURAL DEL BOSQUE SECO TROPICAL DEL CERRO TASAJERO, SAN JOSÉ DE CÚCUTA (NORTE DE SANTANDER), COLOMBIA FLORISTIC AND STRUCTURAL CHARACTERIZATION OF THE TROPICAL DRY FOREST CERRO TASAJERO, SAN JOSE DE CÚCUTA (NORTE DE SANTANDER), COLOMBIA

    OpenAIRE

    Merly Carrillo-Fajardo; Orlando Rivera-Díaz; Roberto Sánchez-Montaño

    2007-01-01

    Se analiza la composición y estructura florística de 0,1 hectárea de bosque seco tropical del Cerro Tasajero, mediante el método propuesto por Gentry, como modificación se registran además individuos con DAP ³ 1 cm. Los resultados de riqueza, al considerar los elementos con DAP ³ 2,5 cm, presentan 281 individuos agrupados en 30 familias, 46 géneros y 60 especies; al añadir los elementos con DAP entre 1 y 2,5 cm (204 individuos), se registran los siguientes valores de diversidad (34 familias, ...

  20. A reservoir trap for antiprotons

    CERN Document Server

    Smorra, Christian; Franke, Kurt; Nagahama, Hiroki; Schneider, Georg; Higuchi, Takashi; Van Gorp, Simon; Blaum, Klaus; Matsuda, Yasuyuki; Quint, Wolfgang; Walz, Jochen; Yamazaki, Yasunori; Ulmer, Stefan

    2015-01-01

    We have developed techniques to extract arbitrary fractions of antiprotons from an accumulated reservoir, and to inject them into a Penning-trap system for high-precision measurements. In our trap-system antiproton storage times > 1.08 years are estimated. The device is fail-safe against power-cuts of up to 10 hours. This makes our planned comparisons of the fundamental properties of protons and antiprotons independent from accelerator cycles, and will enable us to perform experiments during long accelerator shutdown periods when background magnetic noise is low. The demonstrated scheme has the potential to be applied in many other precision Penning trap experiments dealing with exotic particles.

  1. Improving teleportation fidelity in structured reservoirs

    OpenAIRE

    Xie, Yu-Xia; Xi, Xiao-Qiang

    2012-01-01

    Seeking flexible methods to control quantum teleportation in open systems is an important task of quantum communication. In this paper, we study how the super-Ohmic, Ohmic and sub-Ohmic reservoirs affect teleportation of a general one-qubit state. The results revealed that the structures of the reservoirs play a decisive role on quality of teleportation. Particularly, the fidelity of teleportation may be improved by the strong backaction of the non-Markovian memory effects of the reservoir. T...

  2. Review of Geomechanical Application in Reservoir Modeling

    OpenAIRE

    Mahmood Bataee; Sonny Irawan

    2014-01-01

    This study has reviewed the geomechanical considerations and applications in reservoir modeling. Geomechanical studies are applied in the reservoir to establish some features as field subsidence/inflation and stability. The reservoir stress alters with the change in the pressure and temperature either by production or EOR injection/thermal methods. The field subsidence/inflation can damage surface facilities. The change in field new stress state could lead ...

  3. Entanglement trapping in a nonstationary structured reservoir

    OpenAIRE

    Lazarou, C.; Luoma, K; Maniscalco, S.; Piilo, J.; Garraway, B. M.

    2012-01-01

    We study a single two-level atom interacting with a reservoir of modes defined by a reservoir structure function with a frequency gap. Using the pseudomodes technique, we derive the main features of a trapping state formed in the weak coupling regime. Utilizing different entanglement measures we show that strong correlations and entanglement between the atom and the modes are in existence when this state is formed. Furthermore, an unexpected feature for the reservoir is revealed. In the long ...

  4. Resolution of carbonate reservoirs at depth

    International Nuclear Information System (INIS)

    Porous Smackover algal mounds associated with granite knobs produce oil throughout southwestern Alabama. This paper reports on a detailed gravity survey over Vocation Field demonstrates lateral density contrasts between reservoir and non-reservoir rocks that can be measured even when the reservoir depth exceeds 14,000 feet (4270 m). A similar gravity survey combined with standard seismic and subsurface interpretation methods could have drastically increased the success rate and lowered development costs

  5. Time-lapse seismic within reservoir engineering

    OpenAIRE

    Oldenziel, T.

    2003-01-01

    Time-lapse 3D seismic is a fairly new technology allowing dynamic reservoir characterisation in a true volumetric sense. By investigating the differences between multiple seismic surveys, valuable information about changes in the oil/gas reservoir state can be captured. Its interpretation involves different disciplines, of which the main three are: reservoir management, rock physics, and seismics. The main challenge is expressed as "How to optimally benefit from time-lapse seismic". The chall...

  6. Advance reservoir evaluation by using NMR logging

    International Nuclear Information System (INIS)

    Based on brief explanation of the measurement principle for nuclear magnetic resonance (NMR) logging, this paper illustrates the importance of NMR logging in reservoir evaluation through typical case examples. These case examples include: Reservoir characterization and productivity evaluation by using NMR logging, determination of reservoir porosity in complex lithology, identification of oil, water and gas zones under complex reservoir conditions where resistivity log data give poor indication, guiding the implementation of completion and drilling programs, etc. Excellent application results indicate that NMR logging has its special features and advantages in comparison with conventional logging techniques. It is a very practical and very promising logging technology

  7. Development of gas and gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    In the study of gas reservoir development, the first year topics are restricted on reservoir characterization. There are two types of reservoir characterization. One is the reservoir formation characterization and the other is the reservoir fluid characterization. For the reservoir formation characterization, calculation of conditional simulation was compared with that of unconditional simulation. The results of conditional simulation has higher confidence level than the unconditional simulation because conditional simulation considers the sample location as well as distance correlation. In the reservoir fluid characterization, phase behavior calculations revealed that the component grouping is more important than the increase of number of components. From the liquid volume fraction with pressure drop, the phase behavior of reservoir fluid can be estimated. The calculation results of fluid recombination, constant composition expansion, and constant volume depletion are matched very well with the experimental data. In swelling test of the reservoir fluid with lean gas, the accuracy of dew point pressure forecast depends on the component characterization. (author). 28 figs., 10 tabs.

  8. Reservoir management and thermal power generation

    International Nuclear Information System (INIS)

    Thermoelectric power stations on regulated rivers may cause violations in stream temperature standards if the dilution water from the upstream reservoir is not adequate. However, it is possible that such violations would occur over a short period or that there exists an acceptable temperature violation range. A minmax model is developed for determining the minimum value of the maximum violation of the temperature standard, the reservoir storage, and release levels for reservoir-river systems. The model is applied to the Shellmouth Reservoir in Manitoba, Canada

  9. Measuring Greenhouse Gas Emissions From China's Reservoirs

    Science.gov (United States)

    Yang, Le; Lu, Fei; Wang, Xiaoke

    2014-01-01

    Hydroelectricity has typically been regarded as a green energy source, but reservoirs created for its generation emit greenhouse gases (GHGs) just as natural lakes and rivers do. The role of reservoirs in GHG emissions has been overlooked. Substantial amounts of methane (CH4) are emitted from reservoir surfaces every year, which account for about 20% of the total CH4 emission from inland waters. GHG emissions (transferred into carbon dioxide (CO2) equivalents) from some tropical reservoirs even exceed CO2 emissions from thermal power plants if the same amount of electricity is generated.

  10. Health assessment for Lehigh Portland Cement Company, Mason City, Cerro Gordo County, Iowa, Region 10. CERCLIS No. IAD005288634. Preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    1989-08-29

    The Lehigh Portland Cement Company Site is listed by the U.S. Environmental Protection Agency (EPA) on the National Priorities List (NPL). The site consists of approximately 150 acres and is located in the west side of U.S. Highway 65, in the northern section of Mason City, Cerro Gordo County, Iowa. Seven groundwater samples were analyzed together with 1 field blank (E E/FIT). No significant levels of contaminants were found in the private wells except for sodium (23 mg/1) from one residential well of unknown depth. The contaminants of concern are: arsenic, cadmium, lead, sodium, and sulfates. The site is considered to be of public health concern because of the risk resulting from potential exposure to hazardous substances via soil, surface water, groundwater and air.

  11. La minería hidráulica romana desarrollada en el Cerro del Sol (Granada) para explotar sus recursos auríferos

    OpenAIRE

    García-Pulido, Luis José

    2008-01-01

    [ES] La Alhambra se encuentra asentada en el extremo más occidental de un depósito aluvial con el nombre de Cerro del Sol. En este promontorio, que actúa como elemento separador entre las cuencas de los ríos Darro y Genil, está atestiguada la existencia de oro, encontrándose presente en el Conglomerado Alhambra. Con la romanización se inició la explotación a gran escala de los recursos auríferos del sudeste de la península Ibérica, haciendo uso de diversas técnicas propias de la minería hidrá...

  12. Cambios vegetacionales antropogénicos en el Cerro Catedral (Río Negro, Argentina) Human impact and vegetation change in Mt. Catedral (Río Negro, Argentina)

    OpenAIRE

    ALEJANDRO DEZZOTTI; LUIS SANCHOLUZ; MARTIN NAUMANN

    2004-01-01

    En el sector septentrional de la ladera Este del cerro Catedral (41°10’S, 71°30’O, 2.388 m) la práctica del esquí comenzó hace alrededor de 65 años y en la actualidad se desarrolla el centro de deportes invernales más importante de Sudamérica. Se compararon los tipos de vegetación actual y potencial a partir de mapas y fotografías históricas, fotografías aéreas actuales, mapas climáticos y topográficos y la estructura del bosque. La vegetación actual está representada por i) la pradera (10,7%...

  13. Cosmic ray observations at Chacaltaya and Cerro la Negra combined with the Pierre Auger and Milagro observatories: GRBs and search for cosmic ray correlations

    International Nuclear Information System (INIS)

    We consider the possibility to search for cosmic ray phenomena time correlated among distant experiments that are currently running in the world. In particular we consider the correlations of events detected by four experiments: between Milagro, operating in USA, and Cerro La Negra Cosmic Ray Laboratory, under construction in Mexico, and between Chacaltaya, in Bolivia, and Auger Observatory, under construction in Argentina. Almost complete sky coverage with fairly uniform celestial exposure of the northern and the southern hemispheres by the above four experiments at the same time could provide important information on astrophysical phenomena. Search for Gamma Ray Bursts and search for non random coincidence between these experiments seem to be feasible under an international extensive air shower joint experiment with the main goal to watch GRBs and other astrophysical phenomena

  14. Analysis of lateritic material from Cerro Impacto by instrumental neutron activation employing a low-energy photon semiconductor and a high-energy Ge(Li) detector

    International Nuclear Information System (INIS)

    Nineteen elements were determined in four different grain size fractions of a bulk geological material from Cerro Impacto for a study of the physical (mechanical) concentration process of different elements based upon the hardness of the different minerals. The analysis was performed by excitation of the sample with a high, slow neutron flux followed by gamma-ray spectroscopy with both a conventional Ge(Li) high-energy detector and a low-energy photon detector (LEPD). The accuracy of this method was studied with the use of two standard reference materials, SY-2 and SY-3, which are similar to the real samples. The values determined were also compared with a secondary target x-ray fluorescence method for all the elements that were suitable to both methods. Actually, the x-ray fluorescence method was found to be more complementary than competitive. 10 refs., 2 figs., 4 tabs

  15. Justificación y diseño de falsa protección diferencial de barras para S.E Cerro de la Plata

    OpenAIRE

    Feliz Juárez, Javier Fernando

    2009-01-01

    La finalidad de nuestro proyecto es el diseño y justificación de un sistema de protección de barras de alimentación de 45 kV para la subestación eléctrica blindada de “Cerro de la Plata” (Madrid), propiedad de la compañía eléctrica Unión Fenosa Distribución. La particularidad de este diseño radica en la consecución de un sistema de protección de barras de subestación que cumpla las exigencias básicas de los sistemas de protección, sin la utilización de un relé de protección ded...

  16. Edades K/Ar al este del cerro Nahuel Pan, Chubut. Implicancias en la correlacion del Grupo Divisadero y del Choiyoi en el área

    Directory of Open Access Journals (Sweden)

    M.E. Vattuone

    2004-09-01

    Full Text Available Al este del cerro Nahuel Pan, existe una secuencia lávico piroclástica que se apoya en discordancia angular sobre una serie volcánica de composición basandesítica. Se dataron por el método K/Ar, la facies lávica dacítico-andesitica y las volcanitas basandesíticas, obteniéndose edades de 105 ± 5 Ma y de 252 ± 10 Ma respectivamente, lo que ubica a las primeras en el Cretácico, en la base del Miembro Superior del Grupo Divisadero y a las segundas en el Permotriásico, siendo equivalentes en edad al Grupo Choiyoi. Por primera vez se comprueba a esta latitud, en el faldeo oriental del área andina, la presencia de volcanitas pertenecientes a este grupo.

  17. 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.

  18. Estimation of Bank Erosion Due To Reservoir Operation in Cascade (Case Study: Citarum Cascade Reservoir

    Directory of Open Access Journals (Sweden)

    Sri Legowo

    2009-11-01

    Full Text Available Sedimentation is such a crucial issue to be noted once the accumulated sediment begins to fill the reservoir dead storage, this will then influence the long-term reservoir operation. The sediment accumulated requires a serious attention for it may influence the storage capacity and other reservoir management of activities. The continuous inflow of sediment to the reservoir will decrease the capacity of reservoir storage, the reservoir value in use, and the useful age of reservoir. Because of that, the rate of the sediment needs to be delayed as possible. In this research, the delay of the sediment rate is considered based on the rate of flow of landslide of the reservoir slope. The rate of flow of the sliding slope can be minimized by way of each reservoir autonomous efforts. This effort can be performed through; the regulation of fluctuating rate of reservoir surface current that does not cause suddenly drawdown and upraising as well. The research model is compiled using the searching technique of Non Linear Programming (NLP.The rate of bank erosion for the reservoir variates from 0.0009 to 0.0048 MCM/year, which is no sigrificant value to threaten the life time of reservoir.Mean while the rate of watershed sediment has a significant value, i.e: 3,02 MCM/year for Saguling that causes to fullfill the storage capacity in 40 next years (from years 2008.

  19. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, Don; Koerner, Roy; Moos, Dan; Nguyen, John; Phillips, Chris; Tagbor, Kwasi; Walker, Scott

    1999-11-09

    The objectives of this quarterly report are to summarize the work conducted under each task during the reporting period July - September 1998 and to report all technical data and findings as specified in the ''Federal Assistance Reporting Checklist''. The main objective of this project is the transfer of technologies, methodologies, and findings developed and applied in this project to other operators of Slope and Basin Clastic Reservoirs. This project will study methods to identify sands with high remaining oil saturation and to recomplete existing wells using advanced completion technology.

  20. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Roy; Clarke, Don; Walker, Scott

    1999-11-09

    The objectives of this quarterly report was to summarize the work conducted under each task during the reporting period April - June 1998 and to report all technical data and findings as specified in the ''Federal Assistance Reporting Checklist''. The main objective of this project is the transfer of technologies, methodologies, and findings developed and applied in this project to other operators of Slope and Basin Clastic Reservoirs. This project will study methods to identify sands with high remaining oil saturation and to recomplete existing wells using advanced completion technology.

  1. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    International Nuclear Information System (INIS)

    The objectives of this quarterly report was to summarize the work conducted under each task during the reporting period April - June 1998 and to report all technical data and findings as specified in the ''Federal Assistance Reporting Checklist''. The main objective of this project is the transfer of technologies, methodologies, and findings developed and applied in this project to other operators of Slope and Basin Clastic Reservoirs. This project will study methods to identify sands with high remaining oil saturation and to recomplete existing wells using advanced completion technology

  2. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    International Nuclear Information System (INIS)

    The objectives of this quarterly report are to summarize the work conducted under each task during the reporting period July - September 1998 and to report all technical data and findings as specified in the ''Federal Assistance Reporting Checklist''. The main objective of this project is the transfer of technologies, methodologies, and findings developed and applied in this project to other operators of Slope and Basin Clastic Reservoirs. This project will study methods to identify sands with high remaining oil saturation and to recomplete existing wells using advanced completion technology

  3. Exploration on ecological regulation of the reservoirs

    Institute of Scientific and Technical Information of China (English)

    Cai Qihua

    2009-01-01

    Reservoir regulation process in the Yangtze River basin is mainly divided into two types of flood regulation and initiating benefit regulation. The present reservoir management system and operation mode are mainly for dealing with or coordinating of flood control and benefit initiation as well as benefit distribution among various beneficial functions. From the view point of river ecosystem protection, the current regulation mode has two kinds of problems: firstly, most of the reservoir regulation plans do not consider ecosystem protection at downstream of dams and needs of environment protection in reservoir areas; secondly, integrated regulation or management of water resources is ignored. It is very necessary to improve reservoir regulation mode, bearing problems faced by regulation of the Three Gorges reservoir and issues related to cascade development and regulation in Tuojiang and Minjiang River basins in mind. In accordance with the concept of scientific development, and the philosophy of "ensuring a healthy Yangtze River and promoting the har-mony between human and water", taking flood control, benefit initiation and eco-system as a whole, this paper put for-ward the basic consideration to improve reservoir regulation as follows : on the basis of requirements of ecosystem protec-tion at downstream of dams and needs of environment protection in reservoir areas, we should bring the functions of res-ervoir such as flood control and benefit initiation into full play, control the negative influence to the ecosystem at down-stream of dams and the environment in reservoir areas in an endurable scope, and restore the ecosystem and the environ-ment step by step. This paper put forward the relevant regulation process aiming at the idiographic problems such as pro-tection of ecosystem at downstream of dams and environment in reservoir areas, protection of aquatic wildlife species and fish species, regulation of sediment and protection of wetland.

  4. Zooplankton of the Zaporiz’ke Reservoir

    Directory of Open Access Journals (Sweden)

    T. V. Mykolaichuk

    2006-01-01

    Full Text Available The paper is devoted to zooplankton species composition in the Zaporiz’ke Reservoir. The greatest species diversity was found in the macrophyte communities of the upper reservoir’s littoral, but the least zooplankton diversity – in the pelagic zone of the lower reservoir.

  5. Zooplankton of the Zaporiz’ke Reservoir

    OpenAIRE

    T. V. Mykolaichuk

    2006-01-01

    The paper is devoted to zooplankton species composition in the Zaporiz’ke Reservoir. The greatest species diversity was found in the macrophyte communities of the upper reservoir’s littoral, but the least zooplankton diversity – in the pelagic zone of the lower reservoir.

  6. Electromagnetic Heating Methods for Heavy Oil Reservoirs

    International Nuclear Information System (INIS)

    The most widely used method of thermal oil recovery is by injecting steam into the reservoir. A well-designed steam injection project is very efficient in recovering oil, however its applicability is limited in many situations. Simulation studies and field experience has shown that for low injectivity reservoirs, small thickness of the oil-bearing zone, and reservoir heterogeneity limits the performance of steam injection. This paper discusses alternative methods of transferring heat to heavy oil reservoirs, based on electromagnetic energy. They present a detailed analysis of low frequency electric resistive (ohmic) heating and higher frequency electromagnetic heating (radio and microwave frequency). They show the applicability of electromagnetic heating in two example reservoirs. The first reservoir model has thin sand zones separated by impermeable shale layers, and very viscous oil. They model preheating the reservoir with low frequency current using two horizontal electrodes, before injecting steam. The second reservoir model has very low permeability and moderately viscous oil. In this case they use a high frequency microwave antenna located near the producing well as the heat source. Simulation results presented in this paper show that in some cases, electromagnetic heating may be a good alternative to steam injection or maybe used in combination with steam to improve heavy oil production. They identify the parameters which are critical in electromagnetic heating. They also discuss past field applications of electromagnetic heating including technical challenges and limitations

  7. Advances in China's Oil Reservoir Description Technique

    Institute of Scientific and Technical Information of China (English)

    Mu Longxin; Huang Shiyan; Jia Ailin; Rong Jiashu

    1997-01-01

    @@ Oil reservoir description in China has undergone rapid development in recent years. Extensive research carried out at various oilfields and petroleum universities has resulted in the formulation of comprehensive oil reservoir description techniques and methods uniquely suited to the various development phases of China's continental facies. The new techniques have the following characteristics:

  8. Optimal early refill rules for Danjiangkou Reservoir

    Directory of Open Access Journals (Sweden)

    Yun WANG

    2015-10-01

    Full Text Available Water levels in reservoirs are generally not allowed to exceed the flood-limited water level during the flood season, which means that huge amounts of water spill in order to provide adequate storage for flood prevention and that it is difficult to fill the reservoir fully at the end of year. Early reservoir refill is an effective method for addressing the contradiction between the needs of flood control and of comprehensive utilization. This study selected the Danjiangkou Reservoir, which is the water source for the middle route of the South-North Water Diversion Project (SNWDP in China, as a case study, and analyzed the necessity and operational feasibility of early reservoir refill. An early reservoir refill model is proposed based on the maximum average storage ratio, optimized by the progressive optimality algorithm, and the optimal scheduling schemes were obtained. Results show that the best time of refill operation for the Danjiangkou Reservoir is September 15, and the upper limit water level during September is 166 m. The proposed early refill scheme, in stages, can increase the annual average storage ratio from 77.51% to 81.99%, and decrease spilled water from 2.439 × 109 m3 to 1.692 × 109 m3, in comparison to the original design scheme. The suggested early reservoir refill scheme can be easily operated with significant comprehensive benefits, which may provide a good reference for scheduling decision-making.

  9. Water resources review: Wheeler Reservoir, 1990

    Energy Technology Data Exchange (ETDEWEB)

    Wallus, R.; Cox, J.P.

    1990-09-01

    Protection and enhancement of water quality is essential for attaining the full complement of beneficial uses of TVA reservoirs. The responsibility for improving and protecting TVA reservoir water quality is shared by various federal, state, and local agencies, as well as the thousands of corporations and property owners whose individual decisions affect water quality. TVA's role in this shared responsibility includes collecting and evaluating water resources data, disseminating water resources information, and acting as a catalyst to bring together agencies and individuals that have a responsibility or vested interest in correcting problems that have been identified. This report is one in a series of status reports that will be prepared for each of TVA's reservoirs. The purpose of this status report is to provide an up-to-date overview of the characteristics and conditions of Wheeler Reservoir, including: reservoir purposes and operation; physical characteristics of the reservoir and the watershed; water quality conditions: aquatic biological conditions: designated, actual, and potential uses of the reservoir and impairments of those uses; ongoing or planned reservoir management activities. Information and data presented here are form the most recent reports, publications, and original data available. 21 refs., 8 figs., 29 tabs.

  10. Optimal early refill rules for Danjiangkou Reservoir

    Institute of Scientific and Technical Information of China (English)

    Yun WANG; Sheng-lian GUO; Guang YANG; Xing-jun HONG; Ting HU

    2014-01-01

    Water levels in reservoirs are generally not allowed to exceed the flood-limited water level during the flood season, which means that huge amounts of water spill in order to provide adequate storage for flood prevention and that it is difficult to fill the reservoir fully at the end of year. Early reservoir refill is an effective method for addressing the contradiction between the needs of flood control and of comprehensive utilization. This study selected the Danjiangkou Reservoir, which is the water source for the middle route of the South-North Water Diversion Project (SNWDP) in China, as a case study, and analyzed the necessity and operational feasibility of early reservoir refill. An early reservoir refill model is proposed based on the maximum average storage ratio, optimized by the progressive optimality algorithm, and the optimal scheduling schemes were obtained. Results show that the best time of refill operation for the Danjiangkou Reservoir is September 15, and the upper limit water level during September is 166 m. The proposed early refill scheme, in stages, can increase the annual average storage ratio from 77.51% to 81.99%, and decrease spilled water from 2.439×109 m3 to 1.692×109 m3, in comparison to the original design scheme. The suggested early reservoir refill scheme can be easily operated with significant comprehensive benefits, which may provide a good reference for scheduling decision-making.

  11. Identifying and Evaluating of Oil Reservoir

    Institute of Scientific and Technical Information of China (English)

    Yang Haixia

    2002-01-01

    The identification and evaluation of oil reservoir with logging data are one of most important ways in geologic logging services. For the last decades, with the further development of the oil & gas exploration, great advances have been achieved in techniques on the acquisition, processing and interpretative evaluation of logging data. How to identify fluid characteristics and evaluate the productivity in light oil reservoir (the crude density being between 0.74g/cm3 and 0.82g/cm3)has become one of the difficulties.With the establishment of the regional interpretation criterion of the study blocks, the optimized logging parameters that reflect the reservoir characteristics have been used to establish the chart for the interpretation of oil-water reservoir combining with well logging parameters. Then, to begin with geologic reserves of crude in single well, we establish evaluation criterion for productivity in oil reservoir with determining lower limit value of the reservoir and applying the relationship between chart parameters. The techniques are verified in production and get better effect.On the basis of the reservoir characteristics analysis of both basin A and B, We established the evaluation method of static productivity on light oil reservoir with getting quantitative evaluation parameters after quantitatively evaluating the date of core, pyrolysis chromatogram and gas chromatogram. It provides new technique 7 for new well interpretation and old well review, as well as evidence for project.design of well testing.

  12. Reservoir optimization for the synthetic brugge field

    NARCIS (Netherlands)

    Peters, E.; Leeuwenburgh, O.; Egberts, P.J.P.

    2009-01-01

    Increasing availability of data and tools for history matching and optimisation brings the long-term goal of closed loop reservoir management closer. However, still many issues are not solved. An example is the interaction between the history match of the reservoir model and the optimisation. How im

  13. Time-lapse seismic within reservoir engineering

    NARCIS (Netherlands)

    Oldenziel, T.

    2003-01-01

    Time-lapse 3D seismic is a fairly new technology allowing dynamic reservoir characterisation in a true volumetric sense. By investigating the differences between multiple seismic surveys, valuable information about changes in the oil/gas reservoir state can be captured. Its interpretation involves d

  14. Ichthyofauna of the reservoirs of Central Vietnam

    Directory of Open Access Journals (Sweden)

    I. A. Stolbunov

    2012-01-01

    Full Text Available Species composition, distribution and abundance of fish in the pelagic and littoral zone of four reservoirs of Central Vietnam (Suoi Chau, Kam Lam, Da Ban and Suoi Dau were studied first. According to the research data the fish community of the reservoirs is represented by 43 species of 19 fish families.

  15. Geothermal reservoir insurance study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-09

    The principal goal of this study was to provide analysis of and recommendations on the need for and feasibility of a geothermal reservoir insurance program. Five major tasks are reported: perception of risk by major market sectors, status of private sector insurance programs, analysis of reservoir risks, alternative government roles, and recommendations.

  16. Economics of Developing Hot Stratigraphic Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Greg Mines; Hillary Hanson; Rick Allis; Joseph Moore

    2014-09-01

    Stratigraphic geothermal reservoirs at 3 – 4 km depth in high heat-flow basins are capable of sustaining 100 MW-scale power plants at about 10 c/kWh. This paper examines the impacts on the levelized cost of electricity (LCOE) of reservoir depth and temperature, reservoir productivity, and drillhole/casing options. For a reservoir at 3 km depth with a moderate productivity index by hydrothermal reservoir standards (about 50 L/s/MPa, 5.6 gpm/psi), an LCOE of 10c/kWh requires the reservoir to be at about 200°C. This is the upper temperature limit for pumps. The calculations assume standard hydrothermal drilling costs, with the production interval completed with a 7 inch liner in an 8.5 inch hole. If a reservoir at 4 km depth has excellent permeability characteristics with a productivity index of 100 L/s/MPa (11.3 gpm/psi), then the LCOE is about 11 c/kWh assuming the temperature decline rate with development is not excessive (< 1%/y, with first thermal breakthrough delayed by about 10 years). Completing wells with modest horizontal legs (e.g. several hundred meters) may be important for improving well productivity because of the naturally high, sub-horizontal permeability in this type of reservoir. Reducing the injector/producer well ratio may also be cost-effective if the injectors are drilled as larger holes.

  17. Carbon emission from global hydroelectric reservoirs revisited.

    Science.gov (United States)

    Li, Siyue; Zhang, Quanfa

    2014-12-01

    Substantial greenhouse gas (GHG) emissions from hydropower reservoirs have been of great concerns recently, yet the significant carbon emitters of drawdown area and reservoir downstream (including spillways and turbines as well as river reaches below dams) have not been included in global carbon budget. Here, we revisit GHG emission from hydropower reservoirs by considering reservoir surface area, drawdown zone and reservoir downstream. Our estimates demonstrate around 301.3 Tg carbon dioxide (CO2)/year and 18.7 Tg methane (CH4)/year from global hydroelectric reservoirs, which are much higher than recent observations. The sum of drawdown and downstream emission, which is generally overlooked, represents 42 % CO2 and 67 % CH4 of the total emissions from hydropower reservoirs. Accordingly, the global average emissions from hydropower are estimated to be 92 g CO2/kWh and 5.7 g CH4/kWh. Nonetheless, global hydroelectricity could currently reduce approximate 2,351 Tg CO2eq/year with respect to fuel fossil plant alternative. The new findings show a substantial revision of carbon emission from the global hydropower reservoirs. PMID:24943886

  18. Increasing Waterflood Reserves in the Wilmington Oil Field Through Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Chris Phillips; Dan Moos; Don Clarke; John Nguyen; Kwasi Tagbor; Roy Koerner; Scott Walker

    1997-04-10

    This project is intended to increase recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs. Transferring technology so that it can be applied in other sections of the Wilmington Field and by operators in other slope and basin reservoirs is a primary component of the project.

  19. Smart Waterflooding in Carbonate Reservoirs

    DEFF Research Database (Denmark)

    Zahid, Adeel

    porous media. The main conclusion of most previous studies was that it is the rock wettability alteration towards more water wetting condition that helps improving the oil recovery. In the first step of this project, we focused on verifying this conclusion. Coreflooding experiments were carried out using...... imbibition rather than forced flooding. The objective of the third step of this project was to investigate the potential of high salinity waterflooding process by carrying out experiments with reservoir chalk samples. We carried out waterflooding instead of spontaneous imbibition using core plugs with and...... without aging. The total oil recovery, recovery rate and interaction mechanisms of ions with rock were studied for different injected fluids under different temperatures and wettability conditions. Experimental results demonstrate that the oil recovery mechanism under high salinity seawater flooding at...

  20. Reservoir management under geological uncertainty using fast model update

    NARCIS (Netherlands)

    Hanea, R.; Evensen, G.; Hustoft, L.; Ek, T.; Chitu, A.; Wilschut, F.

    2015-01-01

    Statoil is implementing "Fast Model Update (FMU)," an integrated and automated workflow for reservoir modeling and characterization. FMU connects all steps and disciplines from seismic depth conversion to prediction and reservoir management taking into account relevant reservoir uncertainty. FMU del

  1. The Potosi Reservoir Model 2013

    Energy Technology Data Exchange (ETDEWEB)

    Adushita, Yasmin; Smith, Valerie; Leetaru, Hannes

    2014-09-30

    As a part of a larger project co-funded by the United States Department of Energy (US DOE) to evaluate the potential of formations within the Cambro-Ordovician strata above the Mt. Simon as potential targets for carbon sequestration in the Illinois and Michigan Basins, the Illinois Clean Coal Institute (ICCI) requested Schlumberger to evaluate the potential injectivity and carbon dioxide (CO2) plume size of the Cambrian Potosi Formation. The evaluation of this formation was accomplished using wireline data, core data, pressure data, and seismic data from the US DOE-funded Illinois Basin–Decatur Project (IBDP) being conducted by the Midwest Geological Sequestration Consortium in Macon County, Illinois. In 2010, technical performance evaluations on the Cambrian Potosi Formation were performed through reservoir modeling. The data included formation tops from mud logs, well logs from the VW1 and the CCS1 wells, structural and stratigraphic formation from three dimensional (3D) seismic data, and field data from several waste water injection wells for Potosi Formation. Intention was for two million tons per annum (MTPA) of CO2 to be injected for 20 years. In the preceding, the 2010 Potosi heterogeneous model (referred to as the "Potosi Dynamic Model 2010" in this topical report) was re-run using a new injection scenario; 3.2 MTPA for 30 years. The extent of the Potosi Dynamic Model 2010, however, appeared too small for the new injection target. It was not sufficiently large enough to accommodate the evolution of the plume. The new model, Potosi Dynamic Model 2013a, was built by extending the Potosi Dynamic Model 2010 grid to 30 miles x 30 miles (48.3km x48.3km), while preserving all property modeling workflows and layering. This model was retained as the base case of Potosi Dynamic Model 2013a. The Potosi reservoir model was updated to take into account the new data from the verification well VW2 which was drilled in 2012. The new porosity and permeability modeling was

  2. Reinterpretacion estratigráfica y petrología de la Formacion Chuscho, Precordillera de La Rioja Stratigraphical reinterpretation and petrology of the Cerro Chuscho Formation. Precordillera of La Rioja

    Directory of Open Access Journals (Sweden)

    L.E. Fauqué

    2003-06-01

    Full Text Available En la Precordillera de Jagüé (provincia de la Rioja, fueron agrupados bajo la denominación de Andesita Cerro Chuscho los afloramientos de volcanitas de: Punta del Agua, Cerro Chuscho y Las Casitas. Se consideraba a estas rocas comagmáticas, constituyendo el cerro Chuscho un cono subvolcánico heterogéneo compuesto por una autobrecha de flujo, integrada por rocas calcoalcalinas correspondientes al ciclo precordillerano. En este trabajo se asigna a los afloramientos del cerro Chuscho (Formación Chuscho como un complejo de volcanitas máficas intraordovícicas, representado por diques y filones de diabasas y por basaltos de estructura almohadillada. Conforman una facies ofiolítica asociada con las sedimentitas ordovícicas y, por lo tanto, quedarían incluidas en la Faja Ofiolítica Famatiniana, asociada a la apertura de un rift oceánico de cuenca marginal formado durante la acreción de Chilenia en el Cambro-Ordovícico. Sus características parecen cambiar a lo largo del rift, pasando de N-Morb en la Cordillera Frontal a E-Morb (P-MORB en la Precordillera de San Juan y La Rioja; estas diferentes características se deben muchas veces al cambio de elevación del rift respecto del manto. Por su parte, las Andesitas Punta del Agua (Formación Punta del Agua, son andesitas orogénicas de arco volcánico, de acuerdo a sus características geoquímicas, con edades que irían desde el Carbonífero superior al Pérmico inferior.In the region of Precordillera of Jagüe, in La Rioja province, the Palaeozoic volcanic rocks, known as the Punta del Agua, Cerro Chuscho and Las Casitas formations, have been grouped into one unit, the "Andesita Cerro Chuscho". These rocks have been considered to be comagmatic and to form a subvolcanic complex of autoclastic breccias and calc-alkaline lava flows of the precordilleran orogenic cycle. In our study, the Cerro Chuscho Formation is reinterpreted as a mafic volcanic complex. Of Ordovician, it includes dykes

  3. Top-Down, Intelligent Reservoir Model

    Science.gov (United States)

    Mohaghegh, Shahab

    2010-05-01

    Conventional reservoir simulation and modeling is a bottom-up approach. It starts with building a geological model of the reservoir that is populated with the best available petrophysical and geophysical information at the time of development. Engineering fluid flow principles are added and solved numerically so as to arrive at a dynamic reservoir model. The dynamic reservoir model is calibrated using the production history of multiple wells and the history matched model is used to strategize field development in order to improve recovery. Top-Down, Intelligent Reservoir Modeling approaches the reservoir simulation and modeling from an opposite angle by attempting to build a realization of the reservoir starting with the measured well production behavior (history). The production history is augmented by core, log, well test and seismic data in order to increase the accuracy of the Top-Down modeling technique. Although not intended as a substitute for the conventional reservoir simulation of large, complex fields, this novel approach to reservoir modeling can be used as an alternative (at a fraction of the cost) to conventional reservoir simulation and modeling in cases where performing conventional modeling is cost (and man-power) prohibitive. In cases where a conventional model of a reservoir already exists, Top-Down modeling should be considered as a compliment to, rather than a competition for the conventional technique, to provide an independent look at the data coming from the reservoir/wells for optimum development strategy and recovery enhancement. Top-Down, Intelligent Reservoir Modeling starts with well-known reservoir engineering techniques such as Decline Curve Analysis, Type Curve Matching, History Matching using single well numerical reservoir simulation, Volumetric Reserve Estimation and calculation of Recovery Factors for all the wells (individually) in the field. Using statistical techniques multiple Production Indicators (3, 6, and 9 months cum

  4. Recent advances in naturally fractured reservoir modeling

    International Nuclear Information System (INIS)

    Large amounts of oil reserves are contained in naturally fractured reservoirs. Most of these hydrocarbon volumes have been left behind because of the poor knowledge and/or description methodology of those reservoirs. This lack of knowledge has lead to the nonexistence of good quantitative models for this complicated type of reservoirs. The complexity of naturally fractured reservoirs causes the need for integration of all existing information at all scales (drilling, well logging, seismic, well testing, etc.) to provide a reservoir description for such reservoirs. This paper presents an overview of recent advances in naturally fractured reservoir modeling, which were developed to characterize the dual porosity system and to improve hydrocarbon recovery. Two techniques, material balance and numerical simulation, are shown to be supportive of one another. The material balance technique is a good tool for history matching of production performance and defining the system, which is then used as input in the numerical model. However, material balance has significant disadvantages when it comes to prediction, which is the domain of numerical simulation modeling. We present the application of a recently introduced material balance equation based on a dual-system approach. In numerical simulation, the mathematical model to predict fluid flow in anisotropic media is enhanced by using permeability tensors. We also discuss a technique to construct permeability tensors from seismic, well log and well test analysis

  5. Reservoir stimulation techniques to minimize skin factor of Longwangmiao Fm gas reservoirs in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Guo Jianchun

    2014-10-01

    Full Text Available The Lower Cambrian Longwangmiao Fm carbonatite gas reservoirs in the Leshan-Longnüsi Paleouplift in the Sichuan Basin feature strong heterogeneity, well-developed fractures and caverns, and a high content of H2S, so these reservoirs are prone to reservoir damages caused by the invasion of drilling fluid or the improper well completion, so to minimize the reservoir skin factor is key to achieving high yield of oil and gas in this study area. Therefore, based on the geological characteristics of the Longwangmiao reservoirs, the binomial productivity equation was applied to demonstrate the possibility and scientificity of minimizing the skin factor. According to the current status of reservoir stimulation, the overall skin factors of reservoir damage caused by drilling fluid invasion, improper drilling and completion modes etc were analyzed, which shows there is still potential for skin factor reduction. Analysis of reservoir damage factors indicates that the main skin factor of Longwangmiao Fm reservoirs consists of that caused by drilling fluid and by improper completion modes. Along with the minimization of skin factor caused by drilling and improper completion, a fracture-network acidizing process to achieve “non-radial & network-fracture” plug-removal by making good use of natural fractures was proposed according to the characteristics of Longwangmiao Fm carbonatite reservoirs.

  6. [Ecotoxicological value of sediments state from reservoir R-11 of Techa River reservoir cascade].

    Science.gov (United States)

    Priakhin, E A; Bogdanov, G O; Traipitsyna, G A; Deriabina, L V; Stukalov, P M; Aleksandrova, O A; Akleev, A V

    2010-01-01

    Researches of sediments state from reservoir R-11 of tandem Techa river reservoir cascade were made. Shershni (Shershni's reservoir, Chelyabinsk region) was used as reference reservoir. Radiochemical analysis of sediments and water from those reservoirs were made (radioactivity in sediments of R-11 ranged from 240 to 360 kBq/kg of dry weight for 90Sr and from 10 to 161 kBq/kg of dry weight for 137Cs). Hydrobiological researches were included (1) detection of quantitative progress and species composition of Oligochaeta fauna in reservoirs and (2) bioassay of sediments in laboratory conditions with using test-organisms Tubifex culture. Calculation of absorbed dose for Oligochaeta from reservoir R-11 was performed on basis of radiochemical analysis data. Our results indicated that quantitative progress of Oligochaeta in reservoir R-11 was less then progress in Shershni's reservoir. R-11 sediments bioassay did not show any toxic effect by tubificidae in laboratory experiments. Significant dependence for quantitative progress Oligochaeta in reservoir R-11, survival rate and breeding power from absorbed dose rate weren't found. However in subacute research breeding power for animals with higher radiation (absorbed) dose was reduced. PMID:20464971

  7. Improving reservoir history matching of EM heated heavy oil reservoirs via cross-well seismic tomography

    KAUST Repository

    Katterbauer, Klemens

    2014-01-01

    Enhanced recovery methods have become significant in the industry\\'s drive to increase recovery rates from oil and gas reservoirs. For heavy oil reservoirs, the immobility of the oil at reservoir temperatures, caused by its high viscosity, limits the recovery rates and strains the economic viability of these fields. While thermal recovery methods, such as steam injection or THAI, have extensively been applied in the field, their success has so far been limited due to prohibitive heat losses and the difficulty in controlling the combustion process. Electromagnetic (EM) heating via high-frequency EM radiation has attracted attention due to its wide applicability in different environments, its efficiency, and the improved controllability of the heating process. While becoming a promising technology for heavy oil recovery, its effect on overall reservoir production and fluid displacements are poorly understood. Reservoir history matching has become a vital tool for the oil & gas industry to increase recovery rates. Limited research has been undertaken so far to capture the nonlinear reservoir dynamics and significantly varying flow rates for thermally heated heavy oil reservoir that may notably change production rates and render conventional history matching frameworks more challenging. We present a new history matching framework for EM heated heavy oil reservoirs incorporating cross-well seismic imaging. Interfacing an EM heating solver to a reservoir simulator via Andrade’s equation, we couple the system to an ensemble Kalman filter based history matching framework incorporating a cross-well seismic survey module. With increasing power levels and heating applied to the heavy oil reservoirs, reservoir dynamics change considerably and may lead to widely differing production forecasts and increased uncertainty. We have shown that the incorporation of seismic observations into the EnKF framework can significantly enhance reservoir simulations, decrease forecasting

  8. Dispersivity as an oil reservoir rock characteristic

    Energy Technology Data Exchange (ETDEWEB)

    Menzie, D.E.; Dutta, S.

    1989-12-01

    The main objective of this research project is to establish dispersivity, {alpha}{sub d}, as an oil reservoir rock characteristic and to use this reservoir rock property to enhance crude oil recovery. A second objective is to compare the dispersion coefficient and the dispersivity of various reservoir rocks with other rock characteristics such as: porosity, permeability, capillary pressure, and relative permeability. The dispersivity of a rock was identified by measuring the physical mixing of two miscible fluids, one displacing the other in a porous medium. 119 refs., 27 figs., 12 tabs.

  9. Safety drain system for fluid reservoir

    Science.gov (United States)

    England, John Dwight (Inventor); Kelley, Anthony R. (Inventor); Cronise, Raymond J. (Inventor)

    2012-01-01

    A safety drain system includes a plurality of drain sections, each of which defines distinct fluid flow paths. At least a portion of the fluid flow paths commence at a side of the drain section that is in fluid communication with a reservoir's fluid. Each fluid flow path at the side communicating with the reservoir's fluid defines an opening having a smallest dimension not to exceed approximately one centimeter. The drain sections are distributed over at least one surface of the reservoir. A manifold is coupled to the drain sections.

  10. Simulation of Radon Transport in Geothermal Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Semprini, Lewis; Kruger, Paul

    1983-12-15

    Numerical simulation of radon transport is a useful adjunct in the study of radon as an in situ tracer of hydrodynamic and thermodynamic numerical model has been developed to assist in the interpretation of field experiments. The model simulates transient response of radon concentration in wellhead geofluid as a function of prevailing reservoir conditions. The radon simulation model has been used to simulate radon concentration response during production drawdown and two flowrate transient tests in vapor-dominated systems. Comparison of model simulation with experimental data from field tests provides insight in the analysis of reservoir phenomena such as propagation of boiling fronts, and estimates of reservoir properties of porosity and permeability thickness.

  11. The freshwater reservoir effect in radiocarbon dating

    DEFF Research Database (Denmark)

    Philippsen, Bente

    case studies will show the degree of variability of the freshwater reservoir effect over short and long timescales. Radiocarbon dating of recent water samples, aquatic plants and animals, shows that age differences of up to 2000 years can occur within one river. In the Limfjord, freshwater influence...... caused reservoir ages to vary between 250 and 700 years during the period 5400 BC - AD 700. Finally, I will discuss the implications of the freshwater reservoir effect for radiocarbon dating of Mesolithic pottery from inland sites of the Ertebølle culture in Northern Germany....

  12. Reservoir analysis by well log data

    Energy Technology Data Exchange (ETDEWEB)

    Kok, M. [Middle East Technical Univ., Ankara (Turkey). Dept. of Petroleum and Natural Gas Engineering; Gokcal, B.; Ersoy, G. [Tulsa Univ., OK (United States). Dept. of Petroleum Engineering

    2005-04-15

    The aim of this research is to describe and characterize the reservoir sections by well log data. Well logs are used to examine the porosity, water saturation and true resistivity properties of the reservoir. Throughout the project, the data is processed using geostatistical tests that are frequency, histograms, auto-correlation, cross-correlations, linear and multiple regression analysis to find the relations between the variables. Statistical analyses are performed using SPSS software. From the output of the software, the data of the reservoir section would be improved resulting in a higher efficiency in the usage of the data. (Author)

  13. 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

  14. Characterization of post-fire surface cover, soils, and burn severity at the Cerro Grande Fire, New Mexico, using hyperspectral and multispectral remote sensing

    Science.gov (United States)

    Kokaly, R.F.; Rockwell, B.W.; Haire, S.L.; King, T.V.V.

    2007-01-01

    Forest fires leave behind a changed ecosystem with a patchwork of surface cover that includes ash, charred organic matter, soils and soil minerals, and dead, damaged, and living vegetation. The distributions of these materials affect post-fire processes of erosion, nutrient cycling, and vegetation regrowth. We analyzed high spatial resolution (2.4??m pixel size) Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) data collected over the Cerro Grande fire, to map post-fire surface cover into 10 classes, including ash, soil minerals, scorched conifer trees, and green vegetation. The Cerro Grande fire occurred near Los Alamos, New Mexico, in May 2000. The AVIRIS data were collected September 3, 2000. The surface cover map revealed complex patterns of ash, iron oxide minerals, and clay minerals in areas of complete combustion. Scorched conifer trees, which retained dry needles heated by the fire but not fully combusted by the flames, were found to cover much of the post-fire landscape. These scorched trees were found in narrow zones at the edges of completely burned areas. A surface cover map was also made using Landsat Enhanced Thematic Mapper plus (ETM+) data, collected September 5, 2000, and a maximum likelihood, supervised classification. When compared to AVIRIS, the Landsat classification grossly overestimated cover by dry conifer and ash classes and severely underestimated soil and green vegetation cover. In a comparison of AVIRIS surface cover to the Burned Area Emergency Rehabilitation (BAER) map of burn severity, the BAER high burn severity areas did not capture the variable patterns of post-fire surface cover by ash, soil, and scorched conifer trees seen in the AVIRIS map. The BAER map, derived from air photos, also did not capture the distribution of scorched trees that were observed in the AVIRIS map. Similarly, the moderate severity class of Landsat-derived burn severity maps generated from the differenced Normalized Burn Ratio (dNBR) calculation

  15. Mechanistic models of unconventional reservoirs

    Science.gov (United States)

    Ebrahimi, Pouyan Lialekol

    Rock physics models are mathematical relations between porosity, composition and elastic properties of a rock. Unlike in conventional silisiclastic rocks where seismic-to-rock properties are predicted successfully by rock physics models, their application in unconventional reservoirs such as shale, hydrate and carbonates is not fully understood. In light of the vast untapped potential of unconventional resources, their exploration will be easier if a suitable rock physics models become available for quantitative interpretation of seismic data. In this thesis generic, rock physics models that were developed for conventional siliciclastic systems have been used to infer rock properties such as porosity, composition, fluid saturation and pore pressure in shale, gas hydrates and carbonates. Results indicate that elastic properties of these rocks including shale and gas hydrates which can be viewed as grain assemblages can be best predicted by Hashin Shtrikman bounds. For rocks with non-spherical pores and a rather unified matrix such as carbonates where grain-to-grain contacts are not very clear, the Kuster and Toksoz model provide a good description of their dry elastic properties.

  16. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements

    Energy Technology Data Exchange (ETDEWEB)

    Locke, C.D.; Salamy, S.P.

    1991-09-01

    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  17. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Locke, C.D.; Salamy, S.P.

    1991-09-01

    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  18. Destratification of an impounding reservoir using compressed air??case of Mudi reservoir, Blantyre, Malawi

    Science.gov (United States)

    Chipofya, V. H.; Matapa, E. J.

    This paper reviews the operational and cost effectiveness of a compressed air destratification system that was installed in the Mudi reservoir for destratifying the reservoir. Mudi reservoir is a raw water source for the Blantyre Water Board. It has a capacity of 1,400,000 cubic metres. The reservoir is 15.3 m deep at top water level. In the absence of any artificial circulation of air, the reservoir stratifies into two layers. There is a warm epilimnion in the top 3 m of the reservoir, with temperatures ranging from 23 to 26 °C. There is prolific algal growth in this layer. The bottom layer has much lower temperatures, and is oxygen deficient. Under such anaerobic conditions, ammonia, sulphides, iron and manganese are released from the sediments of the reservoir. As a result of nutrient inflow from the catchments, coupled with tropical ambient temperatures, the reservoir is most times infested with blue-green algae. This results into water treatment problems in respect of taste and odour and iron and manganese soluble salts. To abate such problems, air is artificially circulated in the reservoir, near the intake tower, through a perforated pipe that is connected to an electrically driven compressor. This causes artificial circulation of water in the hypolimnion region of the reservoir. As a result of this circulation, a hostile environment that inhibits the propagation of algae is created. Dissolved oxygen and temperature profiles are practically uniform from top to bottom of reservoir. Concentrations of iron and manganese soluble salts are much reduced at any of the draw-off points available for the water treatment process. The paper concludes by highlighting the significant cost savings in water treatment that are accrued from the use of compressed air destratification in impounding water storage reservoirs for the control of algae and other chemical pollutants.

  19. Predicting gas in place in abnormal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Stelly, O.V. II; Farshad, F.F.

    1981-06-01

    Application of the conventional gas material balance equation to abnormally pressured volumetric reservoirs results in erroneous estimates of ultimate recovery. In view of the increasing number and importance of this type of reservoir, the program presented results in more realistic predictions. In abnormally pressured reservoirs, the formation is not supporting as great a portion of the overburden stress. Thus, when pressure is depleted, the sand grains and connate water of the formation expand. These factors tend to reduce the available hydrocarbon pore space acting as a drive mechanism. Thus, production is due to a combination of factors that cause subsequent changes in effective compressibility of the formation rather than just gas compressibility. Hammelindl proposed a correction factor equivalent to the ratio of effective compressibility to gas compressibility. This is applied to the results obtained for normally pressured reservoirs.

  20. The freshwater reservoir effect in radiocarbon dating

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2013-01-01

    The freshwater reservoir effect can result in anomalously old radiocarbon ages of samples from lakes and rivers. This includes the bones of people whose subsistence was based on freshwater fish, and pottery in which fish was cooked. Water rich in dissolved ancient calcium carbonates, commonly known...... order of magnitude and degree of variability of the freshwater reservoir effect over short and long timescales. Radiocarbon dating of recent water samples, aquatic plants, and animals, shows that age differences of up to 2000 14C years can occur within one river. The freshwater reservoir effect has also...... implications for radiocarbon dating of Mesolithic pottery from inland sites of the Ertebølle culture in Northern Germany. The surprisingly old ages of the earliest pottery most probably are caused by a freshwater reservoir effect. In a sediment core from the Limfjord, northern Denmark, the impact of the...

  1. Monitoring Taiwan's Feitsui reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1987-06-01

    Describes the instrumentation program at the Feitsui dam and reservoir, about 30 km from Taipei City in northern Taiwan. Outlines the dam site geology, and the instrumentation designed to monitor ground conditions and dam stability during the construction process.

  2. WATER QUALITY ASSESSMENT OF AMERICAN FALLS RESERVOIR

    Science.gov (United States)

    A water quality model was developed to support a TMDL for phosphorus related to phytoplankton growth in the reservoir. This report documents the conceptual model, available data, model evaluation, and simulation results.

  3. Reservoir enhancements and production technology sequencing

    Energy Technology Data Exchange (ETDEWEB)

    Dusseault, M.B. [Waterloo Univ., ON (Canada). Dept. of Earth Sciences, Porous Media Research Inst.

    2006-07-01

    Criteria used to select production technologies for reservoirs with high levels of sand production were discussed. The paper examined a range of thermal recovery methods including cyclic steam stimulation (CSS) and steam assisted gravity drainage (SAGD). VAPEX, hybrid steam, and in situ combustion processes were reviewed. The review indicated that reservoir processes that involve high levels of sand production, high pressures, and high temperatures can cause changes in porosity and breach or shear barriers and shale beds within reservoirs. The changes can be beneficial to technologies designed to reduce flow path lengths in gravity drainage processes. Reservoir scale changes associated with cold heavy oil production with sand (CHOPS) and steam injection technologies were also discussed. It was concluded that careful sequencing of technologies can have a significant impact on recovery rates. 12 refs., 13 figs.

  4. NYC Reservoirs Watershed Areas (HUC 12)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This NYC Reservoirs Watershed Areas (HUC 12) GIS layer was derived from the 12-Digit National Watershed Boundary Database (WBD) at 1:24,000 for EPA Region 2 and...

  5. Measurement-feedback formalism meets information reservoirs

    Science.gov (United States)

    Shiraishi, Naoto; Matsumoto, Takumi; Sagawa, Takahiro

    2016-01-01

    There have been two distinct formalisms of thermodynamics of information: one is the measurement-feedback formalism, which concerns bipartite systems with measurement and feedback processes, and the other is the information reservoir formalism, which considers bit sequences as a thermodynamic fuel. In this paper, we derive a second-law-like inequality by applying the measurement-feedback formalism to information reservoirs, which provides a stronger bound of extractable work than any other known inequality in the same setup. In addition, we demonstrate that the Mandal-Jarzynski model, which is a prominent model of the information reservoir formalism, is equivalent to a model obtained by the contraction of a bipartite system with autonomous measurement and feedback. Our results provide a unified view on the measurement-feedback and the information-reservoir formalisms.

  6. Flow of a stream through a reservoir

    International Nuclear Information System (INIS)

    If a reservoir is fed from a single source, which may not always be pure, the extent to which the inflowing stream mixes with the water in the reservoir is important for the quality of the water supplied by the reservoir. This question was investigated at the Lingese Reservoir, containing between one and two million cubic metres of water, in the Bergisches Land (North Rhine-Westphalia). The investigation was carried out at four different seasons so that the varying effects of the stream-water temperatures could be studied in relation to the temperature of the reservoir water. The stream was radioactively labelled at the point of inflow into the reservoir, and its flow through the reservoir was measured in length and depth from boats, by means of 1-m-long Geiger counters. In two cases the radioactivity of the outflowing water was also measured at fixed points. A considerable variety of intermixing phenomena were observed; these were mainly of limnological interest. The results of four experiments corresponding to the four different seasons are described in detail. They were as follows: (1) The mid-October experiment where the stream, with a temperature of 8.0 deg. C, was a good 5 deg. C colder than the water of the reservoir, whose temperature was almost uniform, ranging from 13.2 deg. C at the bed to 13.6 deg. C at the surface. (2) The spring experiment (second half of March), when the stream temperature was only 0.3 deg. C below that of the reservoir surface (7.8 deg. C), while the temperature of the bed was 5.8 deg. C. (3) The winter experiment (early December) where at first the temperature of the stream was approximately the same as that of the surface so that, once again, the stream at first flowed 1/2 - 1 m below the surface. During the almost wind-free night a sudden fall in temperature occurred, and the air temperature dropped from 0 deg. C to -12 deg. C. (4) The summer experiment (end of July to mid-August) when the stream was nearly 1 deg. C colder than

  7. Integration of reservoir simulation and geomechanics

    Science.gov (United States)

    Zhao, Nan

    Fluid production from tight and shale gas formations has increased significantly, and this unconventional portfolio of low-permeability reservoirs accounts for more than half of the gas produced in the United States. Stimulation and hydraulic fracturing are critical in making these systems productive, and hence it is important to understand the mechanics of the reservoir. When modeling fractured reservoirs using discrete-fracture network representation, the geomechanical effects are expected to have a significant impact on important reservoir characteristics. It has become more accepted that fracture growth, particularly in naturally fractured reservoirs with extremely low permeability, cannot be reliably represented by conventional planar representations. Characterizing the evolution of multiple, nonplanar, interconnected and possibly nonvertical hydraulic fractures requires hydraulic and mechanical characterization of the matrix, as well as existing latent or healed fracture networks. To solve these challenging problems, a reservoir simulator (Advanced Reactive Transport Simulator (ARTS)) capable of performing unconventional reservoir simulation is developed in this research work. A geomechanical model has been incorporated into the simulation framework with various coupling schemes and this model is used to understand the geomechanical effects in unconventional oil and gas recovery. This development allows ARTS to accept geomechanical information from external geomechanical simulators (soft coupling) or the solution of the geomechanical coupled problem (hard coupling). An iterative solution method of the flow and geomechanical equations has been used in implementing the hard coupling scheme. The hard coupling schemes were verified using one-dimensional and two-dimensional analytical solutions. The new reservoir simulator is applied to learn the influence of geomechanical impact on unconventional oil and gas production in a number of practical recovery scenarios

  8. Technical report on hierarchical reservoir computing architectures

    OpenAIRE

    Wyffels, Francis; Waegeman, Tim; Schrauwen, Benjamin; Jaeger, Herbert

    2012-01-01

    One approach for building architectures (of which an overview was given in D.6.1) in AMARSi is to use reservoir computing. Here, untrained (or unsupervised trained) recurrent neural networks are used for motion control by learning simple readouts on the dynamic representation generated by the dynamic RNN system. Although single reservoirs are able to generate rich and tunable control patterns (as demonstrated in D.4.1), to allow composition of motion or high-level control, these modules need ...

  9. Dynamics of fish spatial distribution in reservoirs

    OpenAIRE

    Říha, Milan

    2012-01-01

    This dissertation thesis focuses on several aspects of fish ecology in reservoirs and the methodology of their sampling. It is divided to three parts. The first part focuses on the dynamics of fish distribution throughout the seasons and between day and night. The second part deals with the efficiency and the selectivity of the beach seine net, trawl and purse seine net. The third part describes the long-term development of fish populations in the Římov Reservoir.

  10. Tourism improvement on Eguzon Reservoir (France)

    OpenAIRE

    Qsair, Zoubida; Touchart, Laurent; Bartout, Pascal

    2014-01-01

    Eguzon reservoir, built in the 1920s as the greatest dam in France, submerged a portion of the Creuse Valley and shocked population and famous artists who painted here the natural landscape. Later, the reservoir was accepted and became a pole for tourism, well equipped in the 1980s. At the present, tourism facilities have aged and the site needs new ideas for developing the country. That is why 200 quantitative questionnaires with tourists and 25 semi-structured interviews with officials and ...

  11. Geophysical monitoring in a hydrocarbon reservoir

    Science.gov (United States)

    Caffagni, Enrico; Bokelmann, Goetz

    2016-04-01

    Extraction of hydrocarbons from reservoirs demands ever-increasing technological effort, and there is need for geophysical monitoring to better understand phenomena occurring within the reservoir. Significant deformation processes happen when man-made stimulation is performed, in combination with effects deriving from the existing natural conditions such as stress regime in situ or pre-existing fracturing. Keeping track of such changes in the reservoir is important, on one hand for improving recovery of hydrocarbons, and on the other hand to assure a safe and proper mode of operation. Monitoring becomes particularly important when hydraulic-fracturing (HF) is used, especially in the form of the much-discussed "fracking". HF is a sophisticated technique that is widely applied in low-porosity geological formations to enhance the production of natural hydrocarbons. In principle, similar HF techniques have been applied in Europe for a long time in conventional reservoirs, and they will probably be intensified in the near future; this suggests an increasing demand in technological development, also for updating and adapting the existing monitoring techniques in applied geophysics. We review currently available geophysical techniques for reservoir monitoring, which appear in the different fields of analysis in reservoirs. First, the properties of the hydrocarbon reservoir are identified; here we consider geophysical monitoring exclusively. The second step is to define the quantities that can be monitored, associated to the properties. We then describe the geophysical monitoring techniques including the oldest ones, namely those in practical usage from 40-50 years ago, and the most recent developments in technology, within distinct groups, according to the application field of analysis in reservoir. This work is performed as part of the FracRisk consortium (www.fracrisk.eu); this project, funded by the Horizon2020 research programme, aims at helping minimize the

  12. MODELLING OF RESERVOIR NETWORK FOR FLOOD CONTROL USING NONLINEAR RESERVOIR ROUTING MODEL

    Directory of Open Access Journals (Sweden)

    ABDULRAHMAN M. K. A.

    2012-07-01

    Full Text Available Network of reservoirs has become a standard hydraulic construct for multipurpose use. In this work, we present a formulation based on nonlinear reservoir method and coupled tank approach to model the reservoir network for flood control. The network of reservoirs consists of both detention and retention pond which give rise to nonlinear system of ODE for the m reservoirs in the network. The inflow consists of rainfall runoff in each sub catchment and discharges from the adjacent reservoirs. On the other hands, the outflow consists of infiltration and discharges. The nonlinear system obtained is linearized about the normal operating height of each reservoir in the network. The discharge term on the last equation is dropped in order to allow all the runoff captured into it. The establishment of relationship between the area of catchment andarea of reservoir give room for the estimation of the forcing function in terms time of concentration rather than in terms of area of the reservoir which is difficult to obtain in an existing network. Two sets of solutions are presented, one at the convergent point and the other the best solution in respect of the lowest point in thereservoirs.

  13. Evaluation of an Empirical Reservoir Shape Function to Define Sediment Distributions in Small Reservoirs

    Directory of Open Access Journals (Sweden)

    Bogusław Michalec

    2015-08-01

    Full Text Available Understanding and defining the spatial distribution of sediment deposited in reservoirs is essential not only at the design stage but also during the operation. The majority of research concerns the distribution of sediment deposition in medium and large water reservoirs. Most empirical methods do not provide satisfactory results when applied to the determination of sediment deposition in small reservoirs. Small reservoir’s volumes do not exceed 5 × 106 m3 and their capacity-inflow ratio is less than 10%. Long-term silting measurements of three small reservoirs were used to evaluate the method described by Rahmanian and Banihashemi for predicting sediment distributions in small reservoirs. Rahmanian and Banihashemi stated that their model of distribution of sediment deposition in water reservoir works well for a long duration operation. In the presented study, the silting rate was used in order to determine the long duration operation. Silting rate is a quotient of volume of the sediment deposited in the reservoir and its original volume. It was stated that when the silting rate had reached 50%, the sediment deposition in the reservoir may be described by an empirical reservoir depth shape function (RDSF.

  14. Hydropower Reservoir Operation using Standard Operating and Standard Hedging Policies

    OpenAIRE

    T.R. Neelakantan; K. Sasireka

    2013-01-01

    Standard operating policy and hedging policies are commonly used for reservoir operation for municipal or irrigation water supply. Application of these policies to hydropower reservoir operation is complex. In this paper, new standard operating policies and standard hedging policy are proposed for hydropower reservoir operation. The newly proposed policies were applied to the operation of Indira Sagar reservoir in India and demonstrated.

  15. 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

    Directory of Open Access Journals (Sweden)

    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

  16. 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

  17. 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

  18. Evolución magmática del Granito Peñón Rosado, Cerro Asperecito, flanco occidental de la sierra de Famatina Magmatic evolution of the Peñón Rosado Granite, Cerro Asperecito, western flank of the Famatina range

    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.Garnet is an uncommon accessory mineral in igneous rocks and is a relevant petrologic topic. Combined petrology, chemistry/mineralogy, whole-rock geochemistry, and isotopic geochemistry studies in the cerro Asperecito indicate that the garnet-bearing granitoids of the Peñón Rosado Granite (PRG were produced by partial melting of metasedimentary rocks and subsequent differentiation during their emplacement at the Early-Middle Ordovician. In this way the PRG1 facies represent an early crystallized, the PRG2 facies

  19. Reservoir assessment of The Geysers Geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R.P.; Chapman, R.H.; Dykstra, H.

    1981-01-01

    Big Sulphur Creek fault zone, in The Geysers Geothermal field, may be part of a deep-seated, wrench-style fault system. Hydrothermal fluid in the field reservoir may rise through conduits beneath the five main anomalies associated with the Big Sulphur Creek wrench trend. Some geophysical anomalies (electrical resistivity and audio-magnetotelluric) evidently are caused by the hot water geothermal field or zones of altered rocks; others (gravity, P-wave delays, and possibly electrical resistivity) probably respresent the underlying heat source, a possible magma chamber; and others (microearthquake activity) may be related to the steam reservoir. A large negative gravity anomaly and a few low-resistivity anomalies suggest areas generally favorable for the presence of steam zones, but these anomalies apparently do not directly indicate the known steam reservoir. At the current generating capacity of 930 MWe, the estimated life of The Geysers Geothermal field reservoir is 129 years. The estimated reservoir life is 60 years for the anticipated maximum generating capacity of 2000 MWe as of 1990. Wells at The Geysers are drilled with conventional drilling fluid (mud) until the top of the steam reservoir is reached; then, they are drilled with air. Usually, mud, temperature, caliper, dual induction, and cement bond logs are run on the wells.

  20. Hierarchy modeling of subsurface palaeochannel reservoir architecture

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The studies on fluvial reservoir architecture are mainly aimed at outcrop and modern deposition,but rarely at the subsurface reservoir,so there are few effective methods to predict the distribution of subsurface reservoir architectures. In this paper,taking the meandering river reservoir of Guantao formation Gudao Oilfield,Jiyang depression,Baohai Gulf Basin,East China as an example,the archi-tectural modeling method of complex meandering belt reservoir is proposed,that is hierarchy con-straint,pattern fitting and multi-dimensional interaction. Architectures of meandering river reservoir can be divided into three hierarchies: meandering channel sandbody,point bar and lateral accretion body. Different hierarchies of the quantitative architecture pattern are fitted to subsurface well data (including dynamic monitoring data) in different hierarchies through one-dimensional hole,2D profiles and plane and 3D space,which are verified by each other. And then 3D model in different hierarchies is established. At the same time,the quantificational relationship between width of active river and the scale of point bar is set up,and the scale of lateral accretion sand body and shale beddings is con-firmed with horizontal well data. The study not only has significant meaning on the development of geology,but also can improve the oilfield exploitation greatly.

  1. The pollution of the 'iron gate' reservoir

    International Nuclear Information System (INIS)

    The paper presents the characteristics of the Iron Gate I (the Djerdap) Water Power and Navigational System, one of the largest in Europe (completed in 1972 by joint efforts of Yugoslavia and Romania). In this paper the attention is devoted to review of the sediment monitoring program and impacts of reservoir sedimentation, as well as to the investigations of water and sediment quality. Special consideration is paid to the issue of sediment pollution research needs. Namely, the hot spot of the 'Iron Gate' sedimentation represents a scarcely known pollution of sediment deposits. The present pollution probably is considerable, since the 'Iron Gate' reservoir drains about 577000 km2, with over 80 million inhabitants, and developed municipal and industrial infrastructure. Therefore, in the thirty-year reservoir life various types of sediment-bound pollutants entered and deposited within it. Especially severe incidents happened during 1999 (as a result of NATO bombing campaign) and 2000 (two accidental pollutions in the Tisza river catchment). The study of the 'Iron Gate' reservoir pollution should be prepared in order to enlighten the present state of reservoir sedimentation and pollution. The main objectives of the study are to enhance the government and public awareness of the present environmental state of the 'Iron Gate' reservoir and to serve as a baseline for all future actions. (author)

  2. Water in chalk reservoirs: 'friend or foe?'

    International Nuclear Information System (INIS)

    Most of the petroleum fields in the Norwegian sector of the North Sea are sandstone reservoirs; the oil and gas are trapped in different species of sandstone. But the Ekofisk Field is a chalk reservoir, which really challenges the operator companies. When oil is produced from chalk reservoirs, water usually gets in and the reservoir subsides. The subsidence may be expensive for the oil companies or be used to advantage by increasing the recovery rate. Since 60 per cent of the world's petroleum reserves are located in carbonate reservoirs, it is important to understand what happens as oil and gas are pumped out. Comprehensive studies at the Department of Petroleum Technology and Applied Geophysics at Stavanger University College in Norway show that the mechanical properties of chalk are considerably altered when the pores in the rock become saturated with oil/gas or water under different stress conditions. The processes are extremely complex. The article also maintains that the effects of injecting carbon dioxide from gas power plants into petroleum reservoirs should be carefully studied before this is done extensively

  3. 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.

  4. 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.

  5. A finite element simulation system in reservoir engineering

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Xiaozhong

    1996-03-01

    Reservoir engineering is performed to predict the future performance of a reservoir based on its current state and past performance and to explore other methods for increasing the recovery of hydrocarbons from a reservoir. Reservoir simulations are routinely used for these purposes. A reservoir simulator is a sophisticated computer program which solves a system of partial differential equations describing multiphase fluid flow (oil, water, and gas) in a porous reservoir rock. This document describes the use of a reservoir simulator version of BOAST which was developed by the National Institute for Petroleum and Energy Research in July, 1991.

  6. Potential methane reservoirs beneath Antarctica.

    Science.gov (United States)

    Wadham, J L; Arndt, S; Tulaczyk, S; Stibal, M; Tranter, M; Telling, J; Lis, G P; Lawson, E; Ridgwell, A; Dubnick, A; Sharp, M J; Anesio, A M; Butler, C E H

    2012-08-30

    Once thought to be devoid of life, the ice-covered parts of Antarctica are now known to be a reservoir of metabolically active microbial cells and organic carbon. The potential for methanogenic archaea to support the degradation of organic carbon to methane beneath the ice, however, has not yet been evaluated. Large sedimentary basins containing marine sequences up to 14 kilometres thick and an estimated 21,000 petagrams (1 Pg equals 10(15) g) of organic carbon are buried beneath the Antarctic Ice Sheet. No data exist for rates of methanogenesis in sub-Antarctic marine sediments. Here we present experimental data from other subglacial environments that demonstrate the potential for overridden organic matter beneath glacial systems to produce methane. We also numerically simulate the accumulation of methane in Antarctic sedimentary basins using an established one-dimensional hydrate model and show that pressure/temperature conditions favour methane hydrate formation down to sediment depths of about 300 metres in West Antarctica and 700 metres in East Antarctica. Our results demonstrate the potential for methane hydrate accumulation in Antarctic sedimentary basins, where the total inventory depends on rates of organic carbon degradation and conditions at the ice-sheet bed. We calculate that the sub-Antarctic hydrate inventory could be of the same order of magnitude as that of recent estimates made for Arctic permafrost. Our findings suggest that the Antarctic Ice Sheet may be a neglected but important component of the global methane budget, with the potential to act as a positive feedback on climate warming during ice-sheet wastage. PMID:22932387

  7. Health assessment for Northwestern States Portland Cement Company, Mason City, Cerro Gordo County, Iowa, Region 7. CERCLIS No. IAD980852461. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-27

    The Northwestern States Portland Cement Company (NWSPCC) NPL site is situated in the northern section of Mason City, Cerro Gordo County, Iowa. The major concern at the site is contaminated surface water and ground water as a result of contact with waste cement kiln dust in the West Quarry. On-site surface water and ground water are contaminated with lead, sodium, sulfates, and reflects high pH. The waste kiln dust is in contact with both the surficial and Devonian aquifers on site; hence, there is a potential for contamination of the Devonian aquifer off-site. Potential exposure pathways of concern include ingestion of contaminated ground water; accidental ingestion and dermal contact with contaminated surface water, and accidental ingestion and dermal contact with contaminated soils and sediment; and inhalation of entrained dust. Under current conditions the NWSPCC NPL site poses no apparent public health hazard. However, potential risk to human health resulting from possible exposure to on-site and off-site hazardous substances exists in the future if the site is not remediated. The site is currently under remediation to mitigate the potential risk.

  8. El volcanismo bimodal del volcán cerro Corona, Alta Sierra de Somún Curá, provincia de Río Negro

    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.

  9. Medición de gas Radón (RN222 en aguas termales del Cerro Pacho, Caldera Coatepeque, El Salvador

    Directory of Open Access Journals (Sweden)

    Ramiro Rodríguez

    2014-06-01

    Full Text Available Se presentan concentraciones de radón (Rn222 y evaluación de radio (Ra226 disueltos en agua. El objetivo es contribuir al monitoreo volcánico, adaptando y validando metodología analítica. El muestreo fue de tipo discreto y mensual, desde junio 2011 hasta marzo 2013. Las concentraciones de radón varían de 0,48 ± 0,1 a 1,54 ± 0,13 Bq/L (promedio 1,24 Bq/L; concentraciones de radio se evaluaron de enero a diciembre 2012, los valores encontrados no demuestran detección de radio al nivel de confianza del 95 % respecto al límite de detección (4,2 mBq/L. En noviembre 2012 se observó disminución de radón, posiblemente relacionado a anomalías de subducción con epicentro a 143 km del cerro Pacho, registrando sismicidad volcánica 40 días antes con incrementos de microsismos y actividad volcano-tectónica. Se ha generado las primeras mediciones de radón en agua termal, estableciendo la línea base para evaluar el comportamiento de estos radionucleidos con la actividad sísmica.

  10. Charnockitic ortho gneisses and mafic granulite s of the Cerro Olivo complex, south-east Uruguay, Part 2: lithogeochemistry, mineral o chemistry and thermo barometry

    International Nuclear Information System (INIS)

    The Cerro Olivo complex in SE-Uruguay shows different kinds of orthogneisses containing biotite, amphibole and/or orthopyroxene-biotite (charnockitic gneisses). Minor occurrences of mafic granulites are associated. They include low and high pressure kinds. We present the lithogeochemistry and compared mineral chemistry analyses of both the charnockitic orthogneisses and the mafic rocks. Theres i a calc-alkaline geochemical affinity of the biotite-bearing and charnockitic gneisses, while the mafic rocks could derive from tholeitic gabbros. These results allow discrininatieg two kinds of mafic rocks: Low and hight MgO contents, both representing respectively garnet-bearing and garnet-free mafic granulites. The orthopyroxene in the Opx-Bt orthogneisses in FE-rich while MgO-rich mafic rocks show hypersthenes. The thermobarometric data of mafic granulites show temperatures higher than 850°C and two contrasting mineral assemblages, one formed by ∼ 1 Kbar and 770° - 800°C (pre-M). and the other by 5.5 Kbar and 680-700° (M). The mineral chemistry suggests the occurrence of contrasting protoliths to explain the stability of two different mineral associations

  11. NUEVOS APORTES AL CONOCIMIENTO DE LA HERPETOFAUNA DE LA FORMACIÓN CERRO AZUL (MIOCENO SUPERIOR, PROVINCIA DE LA PAMPA, ARGENTINA

    Directory of Open Access Journals (Sweden)

    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.

  12. Jurassic tetrapods and flora of Cañadón Asfalto Formation in Cerro Cóndor area, Chubut Province

    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.

  13. Online interactive U.S. Reservoir Sedimentation Survey Database

    Science.gov (United States)

    Gray, J.B.; Bernard, J.M.; Schwarz, G.E.; Stewart, D.W.; Ray, K.T.

    2009-01-01

    In April 2009, the U.S. Geological Survey and the Natural Resources Conservation Service (prior to 1994, the Soil Conservation Service) created the Reservoir Sedimentation Survey Database (RESSED) and Web site, the most comprehensive compilation of data from reservoir bathymetric and dry basin surveys in the United States. RESSED data can be useful for a number of purposes, including calculating changes in reservoir storage characteristics, quantifying rates of sediment delivery to reservoirs, and estimating erosion rates in a reservoir's watershed.

  14. MITIGATION OF SEDIMENTATION HAZARDS DOWNSTREAM FROM RESERVOIRS

    Institute of Scientific and Technical Information of China (English)

    Ellen WOHL; Sara RATHBURN

    2003-01-01

    Many reservoirs currently in operation trap most or all of the sediment entering the reservoir,creating sediment-depleted conditions downstream. This may cause channel adjustment in the form of bank erosion, bed erosion, substrate coarsening, and channel planform change. Channel adjustment may also result from episodic sediment releases during reservoir operation, or from sediment evacuation following dam removal. Channel adjustment to increased sediment influx depends on the magnitude, frequency, duration and grain-size distribution of the sediment releases, and on the downstream channel characteristics. Channel adjustment may occur as a change in substrate sizedistribution, filling of pools, general bed aggradation, lateral instability, change in channel planform,and/or floodplain aggradation. The increased sediment availability may alter aquatic and riparian habitat, reduce water quality, distribute adsorbed contaminants along the river corridor, and provide germination sites for exotic vegetation. Mitigation of these sedimentation hazards requires: (1)mapping grain-size distribution within the reservoir and estimating the grain-size distributions of sediment that will be mobilized through time; (2) mapping shear stress and sediment transport capacity as a function of discharge on the basis of channel units for the length of the river likely to be affected; (3) mapping potential depositional zones, and aquatic habitat and "acceptable losses," along the downstream channel, and comparing these volumes to the total sediment volume stored in the reservoir as a means of estimating total transport capacity required to mobilize reservoir sediment delivered to the channel; (4) designing discharge and sediment release regime (magnitude, frequency,duration) to minimize adverse downstream impacts; and (5) developing plans to remove, treat, contain,or track contaminants, and to restrict establishment of exotic vegetation. The North Fork Poudre River in Colorado is used to

  15. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, Michael L.; Brown, Raymon L.; Civan, Frauk; Hughes, Richard G.

    2001-08-15

    Research continues on characterizing and modeling the behavior of naturally fractured reservoir systems. Work has progressed on developing techniques for estimating fracture properties from seismic and well log data, developing naturally fractured wellbore models, and developing a model to characterize the transfer of fluid from the matrix to the fracture system for use in the naturally fractured reservoir simulator.

  16. Ecotoxicological investigation in cooling water reservoirs of NPP and Dnepr cascade water reservoirs by using biotest

    International Nuclear Information System (INIS)

    Investigation data obtained during 1988-1992 have shown that NPP waste waters effected test-organisms: they induced changes in growth intensity and morphology of Spirodela polyrrhiza and high mortality of spawn and larvae of Salmo gairdneri as well as somatic mutations and mortality in Tradescantia SLC system. It indicates that toxic matters discharge to cooling reservoirs with NPP waste waters. Similar levels of toxicity and genotoxicity were found in Ignalina and Leningrad NPP waste waters, as well as in cooling reservoirs waters. The water of Dnepr cascade reservoirs was more eutrophic, toxic and genotoxic than the water of NPP cooling reservoirs. Water genotoxicity in the Dnepr cascade water reservoirs was equal to that of NPP waste waters. The Kiev reservoir water showed the highest genotoxicity.Bottom sediments of some biotopes of Kiev and Kachovsk water reservoirs were found to be the most genotoxic. The genotoxicity of these bottom sediments was equal to the Ignalina NPP EDS waste water treatment plant sludge, which commonly is utilized as hazardous waste. The use of test-organism system allows to estimate more precisely ecotoxicological situation in water reservoirs - to establish their eutrophic level, to identify radioactive and chemical water and bottom sediments pollution and to reveal synergetic effects of pollutant complex effect. 8 refs., 6 tabs

  17. Application of integrated reservoir management and reservoir characterization to optimize infill drilling, Class II

    Energy Technology Data Exchange (ETDEWEB)

    Bergeron, Jack; Blasingame, Tom; Doublet, Louis; Kelkar, Mohan; Freeman, George; Callard, Jeff; Moore, David; Davies, David; Vessell, Richard; Pregger, Brian; Dixon, Bill; Bezant, Bryce

    2000-03-16

    The major purpose of this project was to demonstrate the use of cost effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability carbonate reservoirs such as the North Robertson (Clearfork) Unit.

  18. Multi-data reservoir history matching for enhanced reservoir forecasting and uncertainty quantification

    KAUST Repository

    Katterbauer, Klemens

    2015-04-01

    Reservoir simulations and history matching are critical for fine-tuning reservoir production strategies, improving understanding of the subsurface formation, and forecasting remaining reserves. Production data have long been incorporated for adjusting reservoir parameters. However, the sparse spatial sampling of this data set has posed a significant challenge for efficiently reducing uncertainty of reservoir parameters. Seismic, electromagnetic, gravity and InSAR techniques have found widespread applications in enhancing exploration for oil and gas and monitoring reservoirs. These data have however been interpreted and analyzed mostly separately, rarely exploiting the synergy effects that could result from combining them. We present a multi-data ensemble Kalman filter-based history matching framework for the simultaneous incorporation of various reservoir data such as seismic, electromagnetics, gravimetry and InSAR for best possible characterization of the reservoir formation. We apply an ensemble-based sensitivity method to evaluate the impact of each observation on the estimated reservoir parameters. Numerical experiments for different test cases demonstrate considerable matching enhancements when integrating all data sets in the history matching process. Results from the sensitivity analysis further suggest that electromagnetic data exhibit the strongest impact on the matching enhancements due to their strong differentiation between water fronts and hydrocarbons in the test cases.

  19. Reservoir Characterization, Production Characteristics, and Research Needs for Fluvial/Alluvial Reservoirs in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Cole, E.L.; Fowler, M.L.; Jackson, S.R.; Madden, M.P.; Raw-Schatzinger, V.; Salamy, S.P.; Sarathi, P.; Young, M.A.

    1999-04-28

    The Department of Energy's (DOE's) Oil Recovery Field Demonstration Program was initiated in 1992 to maximize the economically and environmentally sound recovery of oil from known domestic reservoirs and to preserve access to this resource. Cost-shared field demonstration projects are being initiated in geology defined reservoir classes which have been prioritized by their potential for incremental recovery and their risk of abandonment. This document defines the characteristics of the fifth geological reservoir class in the series, fluvial/alluvial reservoirs. The reservoirs of Class 5 include deposits of alluvial fans, braided streams, and meandering streams. Deposit morphologies vary as a complex function of climate and tectonics and are characterized by a high degree of heterogeneity to fluid flow as a result of extreme variations in water energy as the deposits formed.

  20. A simulation of reservoir induced seismicity at the Tarbela reservoir, Pakistan

    International Nuclear Information System (INIS)

    Tarbela dam on the indus river is a unique case for the Himalayan region as a whole in that high quality pre and post-impoundment seismicity data are available. A recently published analysis of 20 km radial zone centered on the reservoir are suppressed when the reservoir levels are high and they reappear again during periods of low water stand in the reservoir. In this rectangular lake. We find that upper crustal faults deduced from published composite fault plane solutions for pre-impoundment earthquakes in the same radial zone could also be the seats of the earthquakes observed during periods of low water level in the reservoir. The importance of this case history for the possibility of reservoir induced seismicity at future sites of high dams in the Himalaya cannot be over emphasized. (author)

  1. Seismic imaging of reservoir flow properties: Resolving waterinflux and reservoir permeability

    Energy Technology Data Exchange (ETDEWEB)

    Vasco, D.W.; Keers, Henk

    2006-11-27

    Methods for geophysical model assessment, in particuale thecomputation of model parameter resolution, indicate the value and thelimitations of time-lapse data in estimating reservoir flow properties. Atrajectory-based method for computing sensitivities provides an effectivemeans to compute model parameter resolutions. We examine the commonsituation in which water encroaches into a resrvoir from below, as due tothe upward movement of an oil-water contact. Using straight-forwardtechniques we find that, by inclusing reflections off the top and bottomof a reservoir tens of meters thick, we can infer reservoir permeabilitybased upon time-lapse data. We find that, for the caseof water influxfrom below, using multiple time-lapse 'snapshots' does not necessarilyimprove the resolution of reservoir permeability. An application totime-lapse data from the Norne field illustrates that we can resolve thepermeability near a producing well using reflections from threeinterfaces associated with the reservoir.

  2. Comparación entre el componente evaluativo en un ambiente de aprendizaje basado en juegos digitales y el componente evaluativo tradicional, en el tema División Celular para grado séptimo: Estudio de caso en la Institución Educativa CASD José María Espinosa Prieto del municipio de Medellín

    OpenAIRE

    Ortega Gamboa, Liseth

    2015-01-01

    Resumen: Este trabajo consiste en una propuesta metodológica basada en juegos digitales para el concepto de división celular en el grado séptimo de básica secundaria de la Institución Educativa CASD José María Espinosa Prieto en la ciudad de Medellín, la cual busca comparar las prácticas de la evaluación tradicional con la evaluación que se puede realizar en un ambiente digital basado en un videojuego; donde los estudiantes transformen su concepción de evaluación e interactúen de forma lúdica...

  3. Seismic characterization of a reservoir; Caracterisation sismique d`un reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Chaffard, V.

    1996-10-24

    The reservoir studied is formed by a magmatic sill and by metamorphosed and fractured beds of limestones and marls. The aim of this study is to better describe the reservoir by using various sources of information: lithological and petrophysical wire line well parameters and seismic attribute information derived from the seismic dataset. Geological analogies were first studied to understand the geological mechanism that created this distinct reservoir geometry. The most important points are the intrusion mechanism and the deformation that the surrounding beds undergo. In the seismic data, we improved the horizons picking supplied by the affiliate (top sill, top upper metamorphosed zone, base sill, base lower metamorphosed zone) and calculated the seismic attributes between these horizons. The attributes calculated of the attributes maps at the reservoir level is useful to understand the intrusion mechanism: the intrusions are composed by distinct flows organised in a radial manner around feeding chimneys. These maps also allow us to better define the reservoir limits within the field. The correlations between reservoir thicknesses and seismic attributes were then studied: the reservoir thicknesses (sill and metamorphosed beds) only show good correlations with the attributes isochrons and isochrons / frequencies. These relationships were described by linear regressions with correlation coefficients ranging from 0.6 to 0.7. No correlation was observed with the amplitudes. The identified relationships were then used to map the reservoir thickness by geostatistical methods. The tuning effect was also studied. Tuning is the interference between successive top and base reflections within a thin bed (thickness less than a quarter of a wavelength). This affects the attribute responses at the reservoir level and may explain the disappointing correlations between seismic attributes and reservoir parameters. The study of the tuning effect on the volcanic sill indicates that

  4. Getting the Most of the Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Grijalva, Victor E.

    1998-12-31

    This presentation discusses a rigorous, multidisciplinary approach to maximize asset value through improved reservoir understanding and a synergistic combination of teamwork between operators and service companies and best-in-class technology. It outlines a route for implementation and gives two examples of where this is working in practice today. It has always been the dream of oil and gas companies to maximize asset value by optimizing production and recovery. At Schlumberger, the road to reach this goal is called IRO, Integrated Reservoir Optimization. IRO is a next-generation, closed-loop process that will help operators maximize asset value by optimizing the economic performance of oil and gas fields. IRO consists of four interrelated elements: (1) reservoir characterization, (2) development planning, (3) field implementation, and (4) reservoir monitoring and control. It is very important that during each step scientists and engineers from a variety of disciplines are brought together to define reservoir performance and potential. This is a long-term process; much of the technology is available although there are still gaps. The two examples are (1) Lasmo, Dacion, an alliance between Lasmo and Schlumberger for a major project in eastern Venezuela, and (2) Amoco N.W.Hutton field in the North Sea

  5. Tracing fluid flow in geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Rose, P.E.; Adams, M.C. [Univ. of Utah, Salt Lake City, UT (United States)

    1997-12-31

    A family of fluorescent compounds, the polycyclic aromatic sulfonates, were evaluated for application in intermediate- and high-temperature geothermal reservoirs. Whereas the naphthalene sulfonates were found to be very thermally stable and reasonably detectable, the amino-substituted naphthalene sulfonates were found to be somewhat less thermally stable, but much more detectable. A tracer test was conducted at the Dixie Valley, Nevada, geothermal reservoir using one of the substituted naphthalene sulfonates, amino G, and fluorescein. Four of 9 production wells showed tracer breakthrough during the first 200 days of the test. Reconstructed tracer return curves are presented that correct for the thermal decay of tracer assuming an average reservoir temperature of 227{degrees}C. In order to examine the feasibility of using numerical simulation to model tracer flow, we developed simple, two-dimensional models of the geothermal reservoir using the numerical simulation programs TETRAD and TOUGH2. By fitting model outputs to measured return curves, we show that numerical reservoir simulations can be calibrated with the tracer data. Both models predict the same order of elution, approximate tracer concentrations, and return curve shapes. Using these results, we propose a method for using numerical models to design a tracer test.

  6. Microseismic monitoring: a tool for reservoir characterization.

    Science.gov (United States)

    Shapiro, S. A.

    2011-12-01

    Characterization of fluid-transport properties of rocks is one of the most important, yet one of most challenging goals of reservoir geophysics. There are some fundamental difficulties related to using active seismic methods for estimating fluid mobility. However, it would be very attractive to have a possibility of exploring hydraulic properties of rocks using seismic methods because of their large penetration range and their high resolution. Microseismic monitoring of borehole fluid injections is exactly the tool to provide us with such a possibility. Stimulation of rocks by fluid injections belong to a standard development practice of hydrocarbon and geothermal reservoirs. Production of shale gas and of heavy oil, CO2 sequestrations, enhanced recovery of oil and of geothermal energy are branches that require broad applications of this technology. The fact that fluid injection causes seismicity has been well-established for several decades. Observations and data analyzes show that seismicity is triggered by different processes ranging from linear pore pressure diffusion to non-linear fluid impact onto rocks leading to their hydraulic fracturing and strong changes of their structure and permeability. Understanding and monitoring of fluid-induced seismicity is necessary for hydraulic characterization of reservoirs, for assessments of reservoir stimulation and for controlling related seismic hazard. This presentation provides an overview of several theoretical, numerical, laboratory and field studies of fluid-induced microseismicity, and it gives an introduction into the principles of seismicity-based reservoir characterization.

  7. Operational trade-offs in reservoir control

    Science.gov (United States)

    Georgakakos, Aris P.

    1993-11-01

    Reservoir operation decisions require constant reevaluation in the face of conflicting objectives, varying hydrologic conditions, and frequent operational policy changes. Optimality is a relative concept very much dependent on the circumstances under which a decision is made. More than anything else, reservoir management authorities need the means to assess the impacts of various operational options. It is their responsibility to define what is desirable after a thorough evaluation of the existing circumstances. This article presents a model designed to generate operational trade-offs common among reservoir systems. The model avoids an all-encompassing problem formulation and distinguishes three operational modes (levels) corresponding to normal, drought, and flood operations. Each level addresses only relevant system elements and uses a static and a dynamic control module to optimize turbine performance within each planning period and temporally. The model is used for planning the operation of the Savannah River System.

  8. A MATHEMATICAL MODEL OF RESERVOIR SEDIMENTATION

    Institute of Scientific and Technical Information of China (English)

    HUANG Jinchi

    2001-01-01

    Reliable quantitative estimation of bed aggradation or degradation is important for river-training and water management projects. With the development of water resources, sediment problems associated with a dam are becoming more severe. This paper describes some special problems in mathematical model for calculation of degradation and aggradation in a reservoir. The main efforts of this study are on the treatment of some physical processes of fine sediment transport (<0.05 mm). Problems in a reservoir are obviously different from a natural stream, such as the turbid current flow, orifice sediment flushing;and the initiation and consolidation of cohesive sediment deposition. The case of Liujiaxia Reservoir,which is located in the upper reaches of the Yellow River, is employed to verify the model. The results show that the model is applicable in the evaluation of an engineering planing with plenty of fine sediment movement.

  9. Freshwater reservoir effect variability in Northern Germany

    DEFF Research Database (Denmark)

    Philippsen, Bente; Heinemeier, Jan

    2012-01-01

    The freshwater reservoir effect is a potential problem when radiocarbon dating fishbones, shells, human bones or food crusts on pottery from sites next to rivers or lakes. The reservoir age in rivers containing considerable amounts of dissolved 14C-free carbonates can be up to several thousand...... variability that can also be expected for the past. Water DIC from different seasons, and from the same season in different years, has been dated because it is the carbon source in photosynthesis and thus at the basis of the rivers’ food webs. The radiocarbon ages of underwater plants and different parts...... years and may be highly variable. For accurate radiocarbon dating of freshwater-based samples, the order of magnitude of the reservoir effect as well as the degree of variability has to be known. The initial problem in this case was the accurate dating of food crusts on pottery from the Mesolithic sites...

  10. Landfill liners from dam reservoir sediments

    Directory of Open Access Journals (Sweden)

    Koś Karolina

    2016-03-01

    Full Text Available Landfill liners from dam reservoir sediments. Every municipal solid waste landfill has to be properly secured to protect the natural environment from possible leachate. Most often an artificial sealing is used, which is based on a soil liner from cohesive soils (clays, silts. Usability evaluation of bottom sediments from Rzeszowski Reservoir for building these liners was presented in the paper. Sediments from dam reservoirs, gathered as a result of the siltation process, can be a valuable material for earthworks purposes. Determination of their possible ways of usage is important, especially before the planned dredging, because thanks to that this material will not be put on a heap. Based on the analysis of the geotechnical parameters of these sediments it was stated that this material can be preliminary allowed for using in liners.

  11. Reservoir characterization and enhanced oil recovery research

    Energy Technology Data Exchange (ETDEWEB)

    Lake, L.W.; Pope, G.A.; Schechter, R.S.

    1992-03-01

    The research in this annual report falls into three tasks each dealing with a different aspect of enhanced oil recovery. The first task strives to develop procedures for accurately modeling reservoirs for use as input to numerical simulation flow models. This action describes how we have used a detail characterization of an outcrop to provide insights into what features are important to fluid flow modeling. The second task deals with scaling-up and modeling chemical and solvent EOR processes. In a sense this task is the natural extension of task 1 and, in fact, one of the subtasks uses many of the same statistical procedures for insight into the effects of viscous fingering and heterogeneity. The final task involves surfactants and their interactions with carbon dioxide and reservoir minerals. This research deals primarily with phenomena observed when aqueous surfactant solutions are injected into oil reservoirs.

  12. Characterization of oil and gas reservoir heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, N.; Barton, M.D.; Bebout, D.G.; Fisher, R.S.; Grigsby, J.D.; Guevara, E.; Holtz, M.; Kerans, C.; Nance, H.S.; Levey, R.A.

    1992-10-01

    Research described In this report addresses the internal architecture of two specific reservoir types: restricted-platform carbonates and fluvial-deltaic sandstones. Together, these two reservoir types contain more than two-thirds of the unrecovered mobile oil remaining ill Texas. The approach followed in this study was to develop a strong understanding of the styles of heterogeneity of these reservoir types based on a detailed outcrop description and a translation of these findings into optimized recovery strategies in select subsurface analogs. Research targeted Grayburg Formation restricted-platform carbonate outcrops along the Algerita Escarpment and In Stone Canyon In southeastern New Mexico and Ferron deltaic sandstones in central Utah as analogs for the North Foster (Grayburg) and Lake Creek (Wilcox) units, respectively. In both settings, sequence-stratigraphic style profoundly influenced between-well architectural fabric and permeability structure. It is concluded that reservoirs of different depositional origins can therefore be categorized Into a heterogeneity matrix'' based on varying intensity of vertical and lateral heterogeneity. The utility of the matrix is that it allows prediction of the nature and location of remaining mobile oil. Highly stratified reservoirs such as the Grayburg, for example, will contain a large proportion of vertically bypassed oil; thus, an appropriate recovery strategy will be waterflood optimization and profile modification. Laterally heterogeneous reservoirs such as deltaic distributary systems would benefit from targeted infill drilling (possibly with horizontal wells) and improved areal sweep efficiency. Potential for advanced recovery of remaining mobile oil through heterogeneity-based advanced secondary recovery strategies In Texas is projected to be an Incremental 16 Bbbl. In the Lower 48 States this target may be as much as 45 Bbbl at low to moderate oil prices over the near- to mid-term.

  13. Three-dimensional numerical modelling of sediments in water reservoirs

    OpenAIRE

    Hoven, Lisa Emilie

    2010-01-01

    Many places in the world the rivers transport a lot of sediments. When these sediments enter slow flowing areas like a water reservoir, the sediments are deposited. This leads to a reduction in the volume of the reservoir. The object of this project is to do three-dimensional numerical modelling of sediments in a water reservoir in using the SSIIM model. The chosen reservoir is the Angostura reservoir in Costa Rica. This reservoir has significant sediment problems and is flushed two times per...

  14. 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)

    S.P. Rupp

    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

  15. Freshwater reservoir effect variability in Northern Germany

    DEFF Research Database (Denmark)

    Philippsen, B.; Heinemeier, J.

    2013-01-01

    The freshwater reservoir effect is a potential problem when radiocarbon dating fish bones, shells, human bones, or food crusts on pottery from sites near rivers or lakes. The reservoir age in hardwater rivers can be up to several thousand years and may be highly variable. Accurate 14C dating of f...... that can also be expected for the past. This knowledge will be applied to the dating of food crusts on pottery from the Mesolithic sites Kayhude at the Alster River and Schlamersdorf at the Trave River, both in Schleswig-Holstein, northern Germany....

  16. Simulation error models for improved reservoir prediction

    International Nuclear Information System (INIS)

    Successful reservoir prediction requires an accurate estimation of parameters to be used in the reservoir model. This research focuses on developing models for simulation error within the petroleum industry, enabling accurate parameter estimation. The standard approach in the oil industry to parameter estimation in a Bayesian framework includes inappropriate assumptions about the error data. This leads to the parameter estimations being biased and overconfident. An error model is designed to significantly reduce the bias effect and to estimate an accurate range of spread. A 2D viscous fingering example problem will be used to demonstrate both construction of the error model, and the benefits gained in doing so

  17. Characterization of oil and gas reservoir heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The objective of the cooperative research program is to characterize Alaskan reservoirs in terms of their reserves, physical and chemical properties, geologic configuration and structure, and the development potential. The tasks completed during this period include: (1) geologic reservoir description of Endicott Field; (2) petrographic characterization of core samples taken from selected stratigraphic horizons of the West Sak and Ugnu (Brookian) wells; (3) development of a polydispersed thermodynamic model for predicting asphaltene equilibria and asphaltene precipitation from crude oil-solvent mixtures, and (4) preliminary geologic description of the Milne Point Unit.

  18. Aspects of tensor permeability in reservoir simulation

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, C.F.

    2002-04-01

    A number of simulation grids relevant to reservoir engineering practice are studied. The impact of neglecting correct local flux and pressure continuity at the grid cell interfaces is assessed. It is shown that the correct local interface conditions with increased discretisation support lead to improved solutions on non-orthogonal grids with the generation of a full permeability tensor. A full tensor permeability arises even when the permeability is non-isotropic on orthogonal grids. The approach described efficiently includes the permeability tensor contributions from the geometric grid structure, but also implies the importance of modelling the full permeability tensor pressure equation in the reservoir simulation up-scaling process. (orig.)

  19. The glaciogenic reservoir analogue studies project (GRASP)

    DEFF Research Database (Denmark)

    Moscariello, A.; Moreau, Julien; Vegt, P. van der;

    Tunnel galleys are common features in Palaeozoic glacigenic succession in North Afrcica and Middle East and they are amongst the most challenging target for hydrocarbon exploration and developing drilling in these regions. Similarly, these buried valleys form important groundwater reservoirs in...... Quaternary glaciated areas and their nature and sediment composition is critical to drive a sustainable production strategy and assess their vulnerability. Seismic resolution however, often limits the understanding of channel valleys morphology, 3D geometry and internal reservoir distribution, thus...... tunnel valley genesis, sedimentary process and internal architecture. This learning can be used ultimately to improve our predictive capability when exploring and developing natural resources from these geological systems....

  20. [Ecosystem service valuation of Ertan Reservoir watershed in mitigating reservoir sand sedimentation].

    Science.gov (United States)

    Wu, Nan; Gao, Ji-xi; Sudebilige; Ennaanay, Driss; Mendoza, Guillermo F; Luo, Zun-lan; Li, Dai-qing; Tian, Mei-rong

    2009-09-01

    By using software ArcGIS 9.2, an evaluation model was established to simulate the ecosystem service of Ertan Reservoir watershed in mitigating the sand sedimentation in the reservoir. In the meantime, sediment delivery ratio and universal soil loss equation were used to simulate the spatial patterns of the annual sediment yield and sediment retention in the watershed as well as the value during the service life period. In 2000, the total quantity of soil retention in the watershed was 12. 1 x 10(8) t x a(-1). The region with higher soil retention was near the main and branch streams of Yalong River, and that with higher sediment delivery ratio was near the streams and the Ertan Reservoir. The region with higher sediment yield and sediment retention was around the reservoir. The actual sediment yield in the study area was 629.3 x 10(4) t x a(-1), occupying 12.7% of the actual soil erosion volume. Farmland was the most important source of sediment yield, with its sediment yield occupying 62.9% of the total. The contribution of forestland to the mitigation of reservoir sand sedimentation was higher than that of the other lands on a per unit area basis. For the reservoir's designed operating life (100 a), the total value of the watershed in the service of mitigating Ertan Reservoir sand sedimentation was 2.75 billion yuan. PMID:20030147

  1. Beyond peak reservoir storage? A global estimate of declining water storage capacity in large reservoirs

    Science.gov (United States)

    Wisser, Dominik; Frolking, Steve; Hagen, Stephen; Bierkens, Marc F. P.

    2013-09-01

    Water storage is an important way to cope with temporal variation in water supply and demand. The storage capacity and the lifetime of water storage reservoirs can be significantly reduced by the inflow of sediments. A global, spatially explicit assessment of reservoir storage loss in conjunction with vulnerability to storage loss has not been done. We estimated the loss in reservoir capacity for a global data set of large reservoirs from 1901 to 2010, using modeled sediment flux data. We use spatially explicit population data sets as a proxy for storage demand and calculate storage capacity for all river basins globally. Simulations suggest that the net reservoir capacity is declining as a result of sedimentation (˜5% compared to the installed capacity). Combined with increasing need for storage, these losses challenge the sustainable management of reservoir operation and water resources management in many regions. River basins that are most vulnerable include those with a strong seasonal flow pattern and high population growth rates such as the major river basins in India and China. Decreasing storage capacity globally suggests that the role of reservoir water storage in offsetting sea-level rise is likely weakening and may be changing sign.

  2. Limnological succession in reservoirs : a paleolimnological comparison of two methods of reservoir formation

    International Nuclear Information System (INIS)

    The changes in algal and invertebrate communities resulting from the formation and operation of two water reservoirs in Saskatchewan were studied. Lake Diefenbaker was created in 1967 by flooding a river valley, whereas Buffalo Pound Lake was formed in 1952 by impounding the outflow of a shallow lake. Both lakes were studied using a multiple-indicator paleolimnological approach. Algal community composition is similar between the two reservoirs and biomass is distributed evenly among green algae, diatoms, chrysophyte, dinoflagellates, cryptophytes and cyanobacteria. Crustacean zooplankton are also similar between the two reservoirs. Sediment core was retrieved from both reservoirs and analyzed. It was shown that differences in reservoir formation and hydrological regime resulted in distinct patterns of aquatic community change even though the local geology, vegetation, soils, land use and climate were similar. Comparison of paleoecological records from both lakes have made it possible to compare the mechanisms that regulate community ontogeny and production following formation of reservoirs by novo flooding and lake inundation. It was determined that reservoir ontogeny does not inevitably lead to eutrophication. Fossil records have shown that oligotrophication can result from increased lake level stability, reduced erosion and complex ecological interactions among phytoplankton, grazers, and macrophyte populations. 49 refs., 2 tabs., 6 figs

  3. 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.

  4. Perfil infectológico de poblaciones mapuche de Cerro Policía y Aguada Guzmán de la provincia de Río Negro

    Directory of Open Access Journals (Sweden)

    Rey, Jorge Alberto

    1996-01-01

    Full Text Available Nuestro trabajo analiza la prevalencia de marcadores de algunas infecciones que afectan las poblaciones mapuche de Cerro Policía (CP y Aguada Guzmán (AG en la Prov. de Río Negro. Los estudios incluídos son: determinación de anticuerpos anti-Treponema pallidum, anti-Trypanosoma cruzii, anti-Echinococcus granulosus, antígeno de superficie de la Hepatitis B (HBsAg, anticuerpos contra el core de la Hepatitis B (anti-HBc, anticuerpos contra el virus de la Hepatitis A (anti-HAV. Se estudiaron 160 muestras en CP y 83 en AG. Los resultados muestran alta prevalencia para anti-HAV en CP (89.2% y en AG (77.1% y para hidatidosis (10.6% y 9.6% respectivamente. Se hallaron valores nulos o bajos para sífilis (CP: 0.0 % y AG:2.4%. La prevalencia para Chagas fue del 10% en CP y 0.0% en AG. Los datos para Hepatitis B fueron nulos o bajos: HBsAg (CP:0.0% y AG:1.2% y anti-HBc(CP:0.6% y AG:0.0%. Los resultados indican que, aún estando estas dos poblaciones tan próximas muestran diferencias en los perfiles de los marcadores serológicos estudiados. Al comparar las tasas de prevalencia con las de otras poblaciones de América, cada una presenta un perfil diferente que depende de la población y del agente infeccioso considerado.

  5. 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.

  6. Cerros Amarillos: un sistemade alteración de tipo pórfiro de edad Miocena Superior, Cordillera Principal,Provincia de Mendoza

    Directory of Open Access Journals (Sweden)

    Nora Rubinstein

    2009-11-01

    Full Text Available Se describe un área de alteración aflorante en laregión de Cerros Amarillos, ubicada en el curso superior del río Atuel, en laCordillera Principal del sur de Mendoza (35°S, 70°O. La zona de alteraciónestá espacialmente asociada a la Formación Huincán en facies dacítica (Miocenosuperior y está caracterizada por un estadio hidrotermal temprano representadopor alteración potásica con una asociación de biotita-magnetita. A ésta sesobreimpone una paragénesis compuesta por sericita-sílice-carbonato a la que seasocia alteración albítica. Esta fase tardía correspondería a una asociación dealbita-sericita de alto nivel que ocurre a profundidades someras dentro delsistema y es anterior a la etapa fílica. Por otra parte también seidentificaron en el área de alteración cuerpos de endoskarn que corresponden abrechas piroxénicas y vetas de plagioclasa-piroxeno. Las paragénesis dealteración reconocidas permiten asimilarlas, de forma preliminar, a las de lossistemas tipo pórfiro con alteración sódica que, de acuerdo a las relacionesestratigráficas y la información geocronológica existente se vincularíagenéticamente al magmatismo del Mioceno superior.

  7. 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

  8. 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.

  9. Improved characterization of reservoir behavior by integration of reservoir performances data and rock type distributions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, D.K.; Vessell, R.K. [David K. Davies & Associates, Kingwood, TX (United States); Doublet, L.E. [Texas A& M Univ., College Station, TX (United States)] [and others

    1997-08-01

    An integrated geological/petrophysical and reservoir engineering study was performed for a large, mature waterflood project (>250 wells, {approximately}80% water cut) at the North Robertson (Clear Fork) Unit, Gaines County, Texas. The primary goal of the study was to develop an integrated reservoir description for {open_quotes}targeted{close_quotes} (economic) 10-acre (4-hectare) infill drilling and future recovery operations in a low permeability, carbonate (dolomite) reservoir. Integration of the results from geological/petrophysical studies and reservoir performance analyses provide a rapid and effective method for developing a comprehensive reservoir description. This reservoir description can be used for reservoir flow simulation, performance prediction, infill targeting, waterflood management, and for optimizing well developments (patterns, completions, and stimulations). The following analyses were performed as part of this study: (1) Geological/petrophysical analyses: (core and well log data) - {open_quotes}Rock typing{close_quotes} based on qualitative and quantitative visualization of pore-scale features. Reservoir layering based on {open_quotes}rock typing {close_quotes} and hydraulic flow units. Development of a {open_quotes}core-log{close_quotes} model to estimate permeability using porosity and other properties derived from well logs. The core-log model is based on {open_quotes}rock types.{close_quotes} (2) Engineering analyses: (production and injection history, well tests) Material balance decline type curve analyses to estimate total reservoir volume, formation flow characteristics (flow capacity, skin factor, and fracture half-length), and indications of well/boundary interference. Estimated ultimate recovery analyses to yield movable oil (or injectable water) volumes, as well as indications of well and boundary interference.

  10. INCREASING WATERFLOOD RESERVES IN THE WILMINGTON OIL FIELD THROUGH IMPROVED RESERVOIR CHARACTERIZATION AND RESERVOIR MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Scott Walker; Chris Phillips; Roy Koerner; Don Clarke; Dan Moos; Kwasi Tagbor

    2002-02-28

    This project increased recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs. Transferring technology so that it can be applied in other sections of the Wilmington Field and by operators in other slope and basin reservoirs is a primary component of the project. This project used advanced reservoir characterization tools, including the pulsed acoustic cased-hole logging tool, geologic three-dimensional (3-D) modeling software, and commercially available reservoir management software to identify sands with remaining high oil saturation following waterflood. Production from the identified high oil saturated sands was stimulated by recompleting existing production and injection wells in these sands using conventional means as well as a short radius redrill candidate. Although these reservoirs have been waterflooded over 40 years, researchers have found areas of remaining oil saturation. Areas such as the top sand in the Upper Terminal Zone Fault Block V, the western fault slivers of Upper Terminal Zone Fault Block V, the bottom sands of the Tar Zone Fault Block V, and the eastern edge of Fault Block IV in both the Upper Terminal and Lower Terminal Zones all show significant remaining oil saturation. Each area of interest was uncovered emphasizing a different type of reservoir characterization technique or practice. This was not the original strategy but was necessitated by the different levels of progress in each of the project activities.

  11. Reservoir-forming age and its exploration significance to stratigraphic reservoirs in southern Songliao Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Despite many studies concerning the forming age, evolution characteristics and the age of petroleum charging in the Fuxin upheaval of southern Songliao Basin, no consensus has been reached so far. This paper presents the first K-Ar dating of autogenetic illite from stratigraphic petroleum reservoirs in the Fuyu oil layer of the Fuxin upheaval belt. Isotopic test and age calculation were carried out based on the separation and purification of illite mineral, X-diffraction analysis and the detection of scanning electron microscopy. The evolution characteristics of structure, sedimentation, reservoir-forming about the Fuxin upheaval belt were interpreted in terms of the synthetical analysis of "six-type geological history" evolution in southern Songliao Basin. The geologic background of petroleum evolution and reservoir formation are similar in the entire central depression region of southern Songliao Basin. The Changling sag and the Fuxin upheaval belt brought about obvious upheaval-sag separation after the hydrocarbon-generation peak of K2qn1 and the main reservoir-forming period of the Fuyu oil layer, namely reservoir-forming happened before the Fuxin upheaval belt extensively raised. The reservoirs have three characteristics: the hydrocarbon source rock above the reservoir, the oil source in the locality, and the vertical migration. The geological cognition is corrected, that is, oil source came from the Changling sag and migrated from the side direction. The bulk process of petroleum charging in the stratigraphic hydrocarbon reservoirs in the Fuxin upheaval belt of southern Songliao Basin is determined according to the isotopic age of autogenetic illite in combination with the method of fluid inclusions. The cognition is helpful to exactly evaluate the resource potential and exploration direction in the Fuxin upheaval belt, Changling sag and their peripheral areas. The present results indicate that the combination of the two methods (the K-Ar dating of

  12. DEVELOPMENT OF RESERVOIR CHARACTERIZATION TECHNIQUES AND PRODUCTION MODELS FOR EXPLOITING NATURALLY FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Wiggins; Raymon L. Brown; Faruk Civan; Richard G. Hughes

    2002-12-31

    For many years, geoscientists and engineers have undertaken research to characterize naturally fractured reservoirs. Geoscientists have focused on understanding the process of fracturing and the subsequent measurement and description of fracture characteristics. Engineers have concentrated on the fluid flow behavior in the fracture-porous media system and the development of models to predict the hydrocarbon production from these complex systems. This research attempts to integrate these two complementary views to develop a quantitative reservoir characterization methodology and flow performance model for naturally fractured reservoirs. The research has focused on estimating naturally fractured reservoir properties from seismic data, predicting fracture characteristics from well logs, and developing a naturally fractured reservoir simulator. It is important to develop techniques that can be applied to estimate the important parameters in predicting the performance of naturally fractured reservoirs. This project proposes a method to relate seismic properties to the elastic compliance and permeability of the reservoir based upon a sugar cube model. In addition, methods are presented to use conventional well logs to estimate localized fracture information for reservoir characterization purposes. The ability to estimate fracture information from conventional well logs is very important in older wells where data are often limited. Finally, a desktop naturally fractured reservoir simulator has been developed for the purpose of predicting the performance of these complex reservoirs. The simulator incorporates vertical and horizontal wellbore models, methods to handle matrix to fracture fluid transfer, and fracture permeability tensors. This research project has developed methods to characterize and study the performance of naturally fractured reservoirs that integrate geoscience and engineering data. This is an important step in developing exploitation strategies for

  13. Andesita Cerro Bola: Nueva unidad vinculada al magmatismo mioceno de la Cordillera de Olivares, San Juan, Argentina (30°35´S; 69°30´O

    Directory of Open Access Journals (Sweden)

    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.

  14. La avalancha de rocas del cerro Los Cardos (37°10´S,70°53´O) en la región norte de la provincia del Neuquén

    OpenAIRE

    E.F. González Díaz; Folguera, A.; Hermanns, R.

    2005-01-01

    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...

  15. Evolución petrotectónica del distrito minero Cerro Áspero y modelo de emplazamiento de los depósitos wolframíferos, Córdoba

    OpenAIRE

    D. Mutti; S. González Chiozza

    2005-01-01

    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...

  16. Cuerpos intrusivos asociados a las mineralizaciones polimetálicas del depósito Cerro León, área del anticlinal El Tranquilo, Santa Cruz: evidencias geofísicas

    OpenAIRE

    2008-01-01

    Las características geológicas tales como presencia de cuerpos intrusivos y subvolcánicos someros básicos a intermedios y de las mineralizaciones con alto contenido de sulfuros del área del anticlinal El Tranquilo, son particulares y poco representadas en el macizo del Deseado. El depósito polimetálico vetiforme Cerro León presenta una signatura geoquímica-mineralógica que lo diferencia del clásico modelo epitermal de baja sulfuración característico del macizo del Deseado. Los datos aeromagné...

  17. Estrategias de conservación y restauración aplicadas sobre el registro cerámico del sitio los tres cerros 1 (Delta Superior del Paraná, departamento Victoria, Entre Ríos)

    OpenAIRE

    Di Prado, Violeta; Castro, Canela; Prieto, Nelly H.

    2013-01-01

    En esta contribución se presentan los primeros resultados del proyecto de colaboración interdisciplinaria “Estrategias de conservación y técnicas arqueométricas aplicadas sobre el registro cerámico del sitio arqueológico Los Tres Cerros 1 (Delta Superior del Paraná, Departamento Victoria, Entre Ríos)” (CETMIC/ FCNyM, UNLP). El conjunto abordado comprende más de 50.000 piezas e incluye fragmentos de cuencos y ollas, apéndices zoomorfos, masas de arcilla con improntas de dedos, entre otros. La ...

  18. 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

  19. Alteraciones hidrotermales superpuestas: Producto de fluidos de pH neutro y ácido en el cerro Guanaco, macizo del Deseado, Santa Cruz Superposed hydrothermal alterations: Result of neutral and acidic pH fluids in Cerro Guananco, DeseadoMassif, Santa Cruz

    Directory of Open Access Journals (Sweden)

    K. Mykietiuk

    2005-03-01

    Full Text Available Relacionadas a las mineralizaciones epitermales de metales preciosos de la zona Cerro Guanaco, macizo del Deseado, se reconocieron alteraciones producidas por fluidos de pH neutro sobre las que se sobrepuso una alteración producto de fluidos de pH ácido. Los fluidos de pH neutro generaron una alteración argílica caracterizada principalmente por illita con algunos interestratificados de illita-montmorillonita y una propilítica con epidoto, calcita y clorita. Los fluidos de pH ácido generaron una zona de cuarzo poroso y una alteración argílica avanzada con la asociación mineralógica de diásporo, pirofilita, dickita, illita, illita-montmorillonita, caolinita y cuarzo. Teniendo en cuenta la morfología mantiforme de los cuerpos alterados por aguas ácidas junto con sus relaciones de corte con las alteraciones producto de aguas neutras, es posible interpretar a la alteración argílica avanzada como resultado de la circulación de aguas ácidas calentadas por vapor. La presencia de minerales que indican temperaturas del orden de los 250°C se atribuye a una actividad magmática tardía en el área.Epithermal precious metal mineralization is well developed in the Cerro Guanaco area, Deseado Massif. Two different suites of alteration have been recognized, one product of neutral fluids and the other of acid fluids. The neutral suite is characterized by the presence of argillic and propillitic alteration; while the acid suite is formed by advanced argillic alteration with diaspore, pyrophyllite, dickite, illite, illite-montmorillonite and quartz. Coupled with the evidence for the relatively shallow level of erosion in the area, and the alteration body of these zones of advanced argillic alteration, there is a relationship to steam-heated fluids descending fractures below a perched water table.

  20. Radioecological problems of NPP reservoirs-coolers

    International Nuclear Information System (INIS)

    Radioecological problems of NPP reservoir-coolers are considered in connection with thermal effluents and partly radiactive wastes. It is shown that one of real means to reduce undesirable ecological consequences of surplus heat release into the medium is the usage of NPP heated waters in energy-biological and agro-industrial complexes. In case of NPP operation the normalized environmental disposal of a number of radionuclides is specified. In this connection the necessity is pointed out to establish a list of the most dangerous radionuclides to be discharged into water medium by various NPP types, to study their behaviour in main water reservoir components; to determine coefficients of radionuclides accumulation in organisms related to human food chain. Actual is the problem of biological effects which can arise in hydrocenoses of reservoir-coolers as a result of long-term or chronic action of NPP radioactive waste disposal. A wide program of ecological investigations is laid down related to the problem of using NPP water thermal effluents and radioecology of reservoirs-coolers, the realization of the program being initiated in the vicinity of the Beloyarsk NPP

  1. NMPC for Oil Reservoir Production Optimization

    DEFF Research Database (Denmark)

    Völcker, Carsten; Jørgensen, John Bagterp; Thomsen, Per Grove; Stenby, Erling Halfdan

    In this paper, we use nonlinear model predictive control (NMPC) to maximize secondary oil recovery from an oil reservoir by controlling two-phase subsurface porous flow using adjustable down-hole control valves. The resulting optimal control problem is nonlinear and large-scale. We solve this...

  2. Tight gas reservoirs: A visual depiction

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-01

    Future gas supplies in the US will depend on an increasing contribution from unconventional sources such as overpressured and tight gas reservoirs. Exploitation of these resources and their conversion to economically producible gas reserves represents a major challenge. Meeting this challenge will require not only the continuing development and application of new technologies, but also a detailed understanding of the complex nature of the reservoirs themselves. This report seeks to promote understanding of these reservoirs by providing examples. Examples of gas productive overpressured tight reservoirs in the Greater Green River Basin, Wyoming are presented. These examples show log data (raw and interpreted), well completion and stimulation information, and production decline curves. A sampling of wells from the Lewis and Mesaverde formations are included. Both poor and good wells have been chosen to illustrate the range of productivity that is observed. The second section of this document displays decline curves and completion details for 30 of the best wells in the Greater Green River Basin. These are included to illustrate the potential that is present when wells are fortuitously located with respect to local stratigraphy and natural fracturing, and are successfully hydraulically fractured.

  3. Borehole radar modeling for reservoir monitoring applications

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2010-01-01

    The use of down-hole sensors and remotely controlled valves in wells provide enormous benefits to reservoir management and oil production. We suggest borehole radar measurements as a promising technique capable of monitoring the arrival of undesired fluids in the proximity of production wells. The h

  4. Rapidly Exploring Subtle Oil and Gas Reservoirs

    Institute of Scientific and Technical Information of China (English)

    Yao Shiyu

    1997-01-01

    @@ Sponsored by Shandong Petroleum Engineering Society,the second Symposium on Subtle Oil and Gas Reservoir Exploration was held in Qingdao City, Shandong Province during October 21~25, 1996. Shengli Petroleum Administration Bureau and Shell Oil Development Corporation(China) have given support to the symposium.

  5. Predicting reservoir wettability via well logs

    Science.gov (United States)

    Feng, Cheng; Fu, Jinhua; Shi, Yujiang; Li, Gaoren; Mao, Zhiqiang

    2016-06-01

    Wettability is an important factor in controlling the distribution of oil and water. However, its evaluation has so far been a difficult problem because no log data can directly indicate it. In this paper, a new method is proposed for quantitatively predicting reservoir wettability via well log analysis. Specifically, based on the J function, diagenetic facies classification and the piecewise power functions, capillary pressure curves are constructed from conventional logs and a nuclear magnetic resonance (NMR) log respectively. Under the influence of wettability, the latter is distorted while the former remains unaffected. Therefore, the ratio of the median radius obtained from the two kinds of capillary pressure curve is calculated to reflect wettability, a quantitative relationship between the ratio and reservoir wettability is then established. According to the low-permeability core sample capillary pressure curve, NMR {{T}2} spectrum and contact angle experimental data from the bottom of the Upper Triassic reservoirs in western Ordos Basin, China, two kinds of constructing capillary pressure curve models and a predictive wettability model are calibrated. The wettability model is verified through the Amott wettability index and saturation exponent from resistivity measurement and their determined wettability levels are comparable, indicating that the proposed model is quite reliable. In addition, the model’s good application effect is exhibited in the field study. Thus, the quantitatively predicting reservoir wettability model proposed in this paper provides an effective tool for formation evaluation, field development and the improvement of oil recovery.

  6. 4D gravity - fluids monitoring in reservoirs

    Czech Academy of Sciences Publication Activity Database

    Mrlina, Jan

    Doha : IPTC, 2009, s. 1-6. ISBN 978-1-55563-272-4. [International Petroleum Technology Conference /4./. Doha (QA), 07.12.2009-09.12.2009] R&D Projects: GA AV ČR IAA300120905 Institutional research plan: CEZ:AV0Z30120515 Keywords : fluids monitoring * hydrocarbon fields * Arabian-type reservoir Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  7. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.

    1989-01-01

    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  8. Fifteenth workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The Fifteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 23--25, 1990. Major topics included: DOE's geothermal research and development program, well testing, field studies, geosciences, geysers, reinjection, tracers, geochemistry, and modeling.

  9. Adsorption of hydrocarbons in chalk reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, L.

    1996-12-31

    The present work is a study on the wettability of hydrocarbon bearing chalk reservoirs. Wettability is a major factor that influences flow, location and distribution of oil and water in the reservoir. The wettability of the hydrocarbon reservoirs depends on how and to what extent the organic compounds are adsorbed onto the surfaces of calcite, quartz and clay. Organic compounds such as carboxylic acids are found in formation waters from various hydrocarbon reservoirs and in crude oils. In the present investigation the wetting behaviour of chalk is studied by the adsorption of the carboxylic acids onto synthetic calcite, kaolinite, quartz, {alpha}-alumina, and chalk dispersed in an aqueous phase and an organic phase. In the aqueous phase the results clearly demonstrate the differences between the adsorption behaviour of benzoic acid and hexanoic acid onto the surfaces of oxide minerals and carbonates. With NaCl concentration of 0.1 M and with pH {approx_equal} 6 the maximum adsorption of benzoic acid decreases in the order: quartz, {alpha}-alumina, kaolinite. For synthetic calcite and chalk no detectable adsorption was obtaind. In the organic phase the order is reversed. The maximum adsorption of benzoic acid onto the different surfaces decreases in the order: synthetic calcite, chalk, kaolinite and quartz. Also a marked difference in adsorption behaviour between probes with different functional groups onto synthetic calcite from organic phase is observed. The maximum adsorption decreases in the order: benzoic acid, benzyl alcohol and benzylamine. (au) 54 refs.

  10. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.

    1989-12-31

    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  11. Do cyanobacterial picoplankton exist in eutrophic reservoirs?

    Czech Academy of Sciences Publication Activity Database

    Komárková, Jaroslava

    2002-01-01

    Roč. 28, - (2002), s. 497-500. ISSN 0368-0770 R&D Projects: GA AV ČR IBS6017004; GA AV ČR IAA6017803; GA AV ČR KSK2005601 Keywords : reservoir * colonial picocynobacteria Subject RIV: DA - Hydrology ; Limnology

  12. Exponential rate of convergence in current reservoirs

    OpenAIRE

    De Masi, Anna; Presutti, Errico; Tsagkarogiannis, Dimitrios; Vares, Maria Eulalia

    2015-01-01

    In this paper, we consider a family of interacting particle systems on $[-N,N]$ that arises as a natural model for current reservoirs and Fick’s law. We study the exponential rate of convergence to the stationary measure, which we prove to be of the order $N^{-2}$.

  13. Permeability profiles -- key to reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Georgi, D.; Kasap, E.; Tang, X.; Cheng, A.

    1998-06-01

    Three-dimensional seismic data being collected routinely today offer those responsible for reservoir management a detailed picture of the configuration of the subsurface. Often, the porosity of reservoir rocks can also be deduced. However, knowing porosity exists, i.e., that there is pore space and vugs for the storage of hydrocarbons, is important but valueless if hydrocarbons cannot be made to flow into wells. Permeability is the quantity that measures flow capability. Having a permeability profile is the key to reservoir management. Accurate values can be obtained from cores taken during drilling; however, cutting cores is expensive and cores taken to the surface may be damaged or not representative of the reservoir rock of interest. Rotary coring can provide limited permeability data but, generally, insufficient data are available to develop a permeability profile. Here, the authors are concerned with measuring permeability with instruments placed in a well or used for logging a well. They shall discuss permeability-measuring methods available from Western Atlas Logging Services (WALS). Together, they make it possible to obtain continuous permeability in any well without coring or extensive well testing.

  14. Quantitative Prediction of Structural Fractures in Low Permeability Reservoir

    Institute of Scientific and Technical Information of China (English)

    Zeng Lianbo; Tian Chonglu

    1996-01-01

    @@ Low -permeability fractured reservoirs will become increasingly prominent along with the enhanced exploration extent and the emerging moderate-high water content in most of the moderate-high permeability reservoirs of the oil fields in eastern China.

  15. 2007 Hydrologic and Sedimentation Survey of Altus Reservoir

    Data.gov (United States)

    US Bureau of Reclamation, Department of the Interior — Reclamation surveyed Altus Reservoir in November 2006, June 2007, and February 2008 to develop updated reservoir topography and compute the present...

  16. Upscaling in vertically fractured oil reservoirs using homogenization

    OpenAIRE

    Salimi, H.; Bruining, H.

    2009-01-01

    Flow modeling in fractured reservoirs is largely confined to the so-called sugar cube model. Here, however, we consider vertically fractured reservoirs, i.e., the situation that the reservoir geometry can be approximated by fractures enclosed columns running from the base rock to the cap rock (aggregated columns). This article deals with the application of the homogenization method to derive an upscaled equation for fractured reservoirs with aggregated columns. It turns out that vertical flow...

  17. Conflicts between the reservoir water demand and climate changed inflow

    OpenAIRE

    Halmova, Dana

    2004-01-01

    Climate changes expected in future would influence the inflow into a multipurpose reservoir. Will be a reservoir able to supply a real demand for water during those climate conditions? This ability was calculated by rainfall-runoff balance model WBMOD that works with a monthly time step. The input data series of precipitation and air temperature and the observed reservoir outflows were used to express the expected changes of the total runoff and the required reservoir capacity. Input data wer...

  18. Suitable Conditions of Reservoir Simulation for Searching Rule Curves

    OpenAIRE

    Anongrit Kangrang; Chavalit Chaleeraktrakoon

    2008-01-01

    The objective of this study is to carry out a suitable length of inflow record using in the simulation model. The second objective is to find an effect of initial reservoir capacity of reservoir simulation for searching the optimal rule curves. The reservoir simulation model was connected with genetic algorithms to search the optimal rule curves quickly. The model has been applied to determine the optimal rule curves of the Bhumibol and Sirikit Reservoirs (the Chao Phraya River Basin, Thailan...

  19. Reservoir management under consideration of stratification and hydraulic phenomena.

    OpenAIRE

    Nandalal, K.D.W.

    1995-01-01

    Reservoirs are the most important components in a water resources system. They are used to store water to extend its temporal availability. The physical, chemical and biological characteristics of water change when impounded in reservoirs. This implies the possibility of using reservoirs for the control of the quality of water besides merely satisfying the quantity requirement. This study presents several techniques formulated to manage a reservoir when both quantity and quality of water are ...

  20. Use of Ensemble Kalman Filter for Bounded Reservoir

    OpenAIRE

    Darwis, S; A. Y. Gunawan; Wahyuningsih, Sri; Sunusi, Nurtiti; Mutaqin, K.; Fitriyati, Nina

    2010-01-01

    The Ensemble Kalman Filter (EnKF) has been used for history matching of the reservoir models. The methodology can be used to estimate the correlation between reservoir properties (permeability, porosity) and reservoir response (pressure, flow rate). Recent studies show that the methodology is promising, however the methodology is novel to reservoir simulation, and further research of the filter is needed for practicing community. The main scope of this paper is to explore the applicability of...

  1. First assessment of the ecological status of Karaoun reservoir, Lebanon

    International Nuclear Information System (INIS)

    Many reservoirs have been constructed throughout the world during the 20th century, with many also suffering from eutrophication. The resulting increased phytoplankton biomass in reservoirs impairs their use. Except for Lake Kinneret, the environmental status of lakes and reservoirs in the Middle East is poorly documented. Karaoun reservoir, also known as Qaroun, Qaraoun or Qarun, is the largest water body in Lebanon, having been constructed for irrigation and hydropower production. This present study reviews Karaoun reservoir, including its characteristics, uses, water quality and phytoplankton succession, to assess the environmental status of the reservoir on the basis of the few existing previous publications about the reservoir. Since 2004, which is 39 years after its construction, the reservoir is considered to be hypereutrophic, with low phytoplankton biodiversity and regular blooms of toxic cyanobacteria. The nutrient and trace metal concentrations would not prevent use of the reservoir for a drinking water supply for Beirut, as is currently being planned, although not all the micropollutants in the lake were documented. Karaoun reservoir is compared to other monitored lakes and reservoirs around the Mediterranean Sea. They share annual toxic cyanobacteria blooms of Aphanizomenon ovalisporum and of Microcystis aeruginosa. The phytoplankton composition and succession of Karaoun reservoir is more similar to El Gergal reservoir (Spain) than nearby natural lakes such as Lake Kinneret (Israel) and Lake Trichonis (Greece). Phytoplankton diversity in Karaoun reservoir was the lowest, due to higher nutrient concentrations and a larger decrease in water level in the dry season. Karaoun reservoir represents an interesting example of the potential response of the phytoplankton community in other lakes and reservoirs during the drought periods expected to occur as a result of global climate change. (author)

  2. 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

    OpenAIRE

    E.F. González Díaz; Folguera, A.; Hermanns, R.

    2005-01-01

    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...

  3. Increasing Waterflood Reserves in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, D.; Koerner, R.; Moos D.; Nguyen, J.; Phillips, C.; Tagbor, K.; Walker, S.

    1999-04-05

    This project used advanced reservoir characterization tools, including the pulsed acoustic cased-hole logging tool, geologic three-dimensional (3-D) modeling software, and commercially available reservoir management software to identify sands with remaining high oil saturation following waterflood. Production from the identified high oil saturated sands was stimulated by recompleting existing production and injection wells in these sands using conventional means as well as a short radius redrill candidate.

  4. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, Michael L; Brown, Raymon L.; Civan, Faruk; Hughes, Richard G.

    2002-10-08

    During this reporting period, research was continued on characterizing and modeling the behavior of naturally fractured reservoir systems. This report proposed a model to relate the seismic response to production data to determine crack spacing and aperture, provided details of tests of proposed models to obtain fracture properties from conventional well logs with actual field data, and verification of the naturally fractured reservoir simulator developed in this project.

  5. 49 CFR 229.51 - Aluminum main reservoirs.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Aluminum main reservoirs. 229.51 Section 229.51... Aluminum main reservoirs. (a) Aluminum main reservoirs used on locomotives shall be designed and fabricated as follows: (1) The heads and shell shall be made of Aluminum Association Alloy No. 5083-0,...

  6. Influence of reservoir parameters and steam rate on SAGD process in a reservoir with gas cap

    Energy Technology Data Exchange (ETDEWEB)

    Barillas, J.L.M.; Dutra, T.V.Jr. [Rio Grande do Norte Federal Univ., Natal (Brazil). Dept. of Chemical Engineering; Mata, W. [Rio Grande do Norte Federal Univ., Natal (Brazil). Dept. of Electrical Engineering

    2008-07-01

    The process of steam injection in heavy oil reservoirs involves heating the reservoir to reduce oil viscosity and increase oil-phase mobility. Steam assisted gravity drainage is one of the most promising thermal recovery methods that has been used in countries such as Canada, the United States and Venezuela, but not in Brazil. This study verified if the process could be applied in Brazilian reservoirs. In particular, a reservoir with northeast Brazilian characteristics was studied in a homogeneous model with a gas cap. The STARS software from CMG was used for all cases. The steam requirement was optimized based on an economical study in which a simplified calculation for net present value (NPV) was obtained. The calculation depended on factors such as cumulative oil, steam injected volume, steam/oil cost ratio, net production cost and, oil price and internal return rate. This function made it possible to perform a steam optimization for different systems with maximal NPV. It was determined that optimal steam rate depends on reservoir characteristics. The thickness of the gas cap was found to have little influence on oil recovery. It was concluded that the optimal steam injection rate can be determined for maximal NPV depending on the physical characteristics of the reservoir. 9 refs., 3 tabs., 10 figs.

  7. Fractured unconventional reservoirs in the Crystalline Basement

    Science.gov (United States)

    Plotnikova, Irina

    2015-04-01

    Since the late 1960-es, the crystalline basement of Tatarstan has been in the focus of intense geological and geophysical surveys. Since 1975, within the framework of the Subsoil Survey Program of Tatarstan, two extra deep wells have been drilled in the Republic, including: 20000-Minnibaevskaya well (bottomhole depth - 5,099 m, meters drilled in the basement - 3,215 m) and 20009-Novoelkhovskaya well (bottomhole depth - 5,881 m, meters drilled in the basement - 4,077 m), as well as 24 wells penetrating the basement at depth from 100 to 2,432 m. Reservoir properties of the crystalline basement rocks can be evaluated based on the resulting volumes of produced liquid, which vary from 0.027 to 125 m3/day. The highest flow rate was registered for well № 20000 Minnibaevskaya. Therefore, there are high-capacity reservoir zones in the crystalline basement of the eastern margin of the Russian Platform. The statement saying that natural reservoirs with significant sizes and fluid storage capacities occur everywhere within the Precambrian crystalline massive on the territory of Tatarstan can be justified by the following provisions: - deconsolidation and fracturing zones of the crystalline basement are registered by a full set of geological and geophysical methods applied in the process of geophysical well surveys and in the process of surface geophysical studies; - there is a certain regular pattern of crystalline basement zone distribution by area and by profile. Wide-spaced drilling into the crystalline basement helped to identify numerous zones of deconsolidation and fracturing with different fluid storage capacity and different extent of fluid saturation. Thickness of the crystalline basement reservoir zones varies from several meters to dozens of meters. Such zones were identified close to the crystalline basement top, As well as at depths more than 5 km. Well log survey was the key method used for reservoir differentiation in the crystalline basement. In total, 16

  8. Third workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P. (eds.)

    1977-12-15

    The Third Workshop on Geothermal Reservoir Engineering convened at Stanford University on December 14, 1977, with 104 attendees from six nations. In keeping with the recommendations expressed by the participants at the Second Workshop, the format of the Workshop was retained, with three days of technical sessions devoted to reservoir physics, well and reservoir testing, field development, and mathematical modeling of geothermal reservoirs. The program presented 33 technical papers, summaries of which are included in these Proceedings. Although the format of the Workshop has remained constant, it is clear from a perusal of the Table of Contents that considerable advances have occurred in all phases of geothermal reservoir engineering over the past three years. Greater understanding of reservoir physics and mathematical representations of vapor-dominated and liquid-dominated reservoirs are evident; new techniques for their analysis are being developed, and significant field data from a number of newer reservoirs are analyzed. The objectives of these workshops have been to bring together researchers active in the various physical and mathematical disciplines comprising the field of geothermal reservoir engineering, to give the participants a forum for review of progress and exchange of new ideas in this rapidly developing field, and to summarize the effective state of the art of geothermal reservoir engineering in a form readily useful to the many government and private agencies involved in the development of geothermal energy. To these objectives, the Third Workshop and these Proceedings have been successfully directed. Several important events in this field have occurred since the Second Workshop in December 1976. The first among these was the incorporation of the Energy Research and Development Administration (ERDA) into the newly formed Department of Energy (DOE) which continues as the leading Federal agency in geothermal reservoir engineering research. The Third

  9. Modeling Reservoir-River Networks in Support of Optimizing Seasonal-Scale Reservoir Operations

    Science.gov (United States)

    Villa, D. L.; Lowry, T. S.; Bier, A.; Barco, J.; Sun, A.

    2011-12-01

    HydroSCOPE (Hydropower Seasonal Concurrent Optimization of Power and the Environment) is a seasonal time-scale tool for scenario analysis and optimization of reservoir-river networks. Developed in MATLAB, HydroSCOPE is an object-oriented model that simulates basin-scale dynamics with an objective of optimizing reservoir operations to maximize revenue from power generation, reliability in the water supply, environmental performance, and flood control. HydroSCOPE is part of a larger toolset that is being developed through a Department of Energy multi-laboratory project. This project's goal is to provide conventional hydropower decision makers with better information to execute their day-ahead and seasonal operations and planning activities by integrating water balance and operational dynamics across a wide range of spatial and temporal scales. This presentation details the modeling approach and functionality of HydroSCOPE. HydroSCOPE consists of a river-reservoir network model and an optimization routine. The river-reservoir network model simulates the heat and water balance of river-reservoir networks for time-scales up to one year. The optimization routine software, DAKOTA (Design Analysis Kit for Optimization and Terascale Applications - dakota.sandia.gov), is seamlessly linked to the network model and is used to optimize daily volumetric releases from the reservoirs to best meet a set of user-defined constraints, such as maximizing revenue while minimizing environmental violations. The network model uses 1-D approximations for both the reservoirs and river reaches and is able to account for surface and sediment heat exchange as well as ice dynamics for both models. The reservoir model also accounts for inflow, density, and withdrawal zone mixing, and diffusive heat exchange. Routing for the river reaches is accomplished using a modified Muskingum-Cunge approach that automatically calculates the internal timestep and sub-reach lengths to match the conditions of

  10. An Intelligent Systems Approach to Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Shahab D. Mohaghegh; Jaime Toro; Thomas H. Wilson; Emre Artun; Alejandro Sanchez; Sandeep Pyakurel

    2005-08-01

    Today, the major challenge in reservoir characterization is integrating data coming from different sources in varying scales, in order to obtain an accurate and high-resolution reservoir model. The role of seismic data in this integration is often limited to providing a structural model for the reservoir. Its relatively low resolution usually limits its further use. However, its areal coverage and availability suggest that it has the potential of providing valuable data for more detailed reservoir characterization studies through the process of seismic inversion. In this paper, a novel intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used as an intermediate step between the well logs and the surface seismic. A synthetic seismic model is developed by using real data and seismic interpretation. In the example presented here, the model represents the Atoka and Morrow formations, and the overlying Pennsylvanian sequence of the Buffalo Valley Field in New Mexico. Generalized regression neural network (GRNN) is used to build two independent correlation models between; (1) Surface seismic and VSP, (2) VSP and well logs. After generating virtual VSP's from the surface seismic, well logs are predicted by using the correlation between VSP and well logs. The values of the density log, which is a surrogate for reservoir porosity, are predicted for each seismic trace through the seismic line with a classification approach having a correlation coefficient of 0.81. The same methodology is then applied to real data taken from the Buffalo Valley Field, to predict inter-well gamma ray and neutron porosity logs through the seismic line of interest. The same procedure can be applied to a complete 3D seismic block to obtain 3D distributions of reservoir properties with less uncertainty than the geostatistical

  11. High-resolution mass spectrometric analysis of a vanadyl porphyrin fraction isolated from the {gt}700{degree}C resid of Cerro Negro heavy petroleum

    Energy Technology Data Exchange (ETDEWEB)

    Grigsby, R.D.; Green, J.B. [National Institute for Petroleum and Energy Research, Bartlesville, OK (United States). BDM-Oklahoma, Inc.

    1997-05-01

    A vanadium-enriched fraction from the {gt}700{degree}C resid of Cerro Negro heavy petroleum was analyzed by high-resolution, low-energy, electron-ionization mass spectrometry (low eV HR/MS). This fraction was known to contain 4.6 wt% of the total vanadium in the whole resid. On the basis of UV-visible absorption spectra, the concentration of porphyrinic vanadium in the fraction was previously estimated to be 56.4 wt% of the total vanadium. Because the porphyritic vanadium accounted for only about one-half of the total, an independent method was needed to characterize the nonporphyrinic vanadium in the fraction. Low-eV HR/MS with sample introduction by probe microdistillation was selected. Etioporphyrins (C{sub n}H{sub 2n-2}N{sub 4}VO) with molecular weights ranging from 487 to 879 were found to be the most abundant vanadium-containing compounds in the fraction. Deoxophylloerythroetio-porphyrins (C{sub n}H{sub 2n-30}N{sub 4}VO) with molecular weights ranging from 499 to 863 were the second most abundant. In addition, other compound types have the formula C{sub n}H{sub 2n+z}N{sub 4}VO, where z ranges from -32 to -50, excluding -46, were found. Additional saturated and aromatic rings present in compounds with more negative z numbers would appreciably alter their UV-visible absorption spectra relative to those of etioporphyrins. That is, the response of the other porphyrin types would be lower than that of etioporphyrins at 570 nm, the wavelength used for the determination of vanadyl porphyrin. Thus, the broad distribution of vanadyl porphyrin types identified in the fraction by low-eV HR/MS strongly suggests that at least a part of the apparent nonporphyrinic vanadium thought to be present in the fraction is, in fact, porphyrinic and is explained by the use of molar absorptivities based solely on those of etioporphyrins to calculate total porphyrin content. 48 refs., 7 figs., 2 tabs.

  12. 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 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 measured fluid inclusion temperatures. A striking aspect of the Marianas-San Marcos vein system is that the high

  13. Method of extracting heat from dry geothermal reservoirs

    Science.gov (United States)

    Potter, R.M.; Robinson, E.S.; Smith, M.C.

    1974-01-22

    Hydraulic fracturing is used to interconnect two or more holes that penetrate a previously dry geothermal reservoir, and to produce within the reservoir a sufficiently large heat-transfer surface so that heat can be extracted from the reservoir at a usefully high rate by a fluid entering it through one hole and leaving it through another. Introduction of a fluid into the reservoir to remove heat from it and establishment of natural (unpumped) convective circulation through the reservoir to accomplish continuous heat removal are important and novel features of the method. (auth)

  14. Modelling longitudinal temperature distribution in TVA Reservoir System

    International Nuclear Information System (INIS)

    The Tennessee Valley Authority (TVA) reservoir system includes over 40 major dams and multi-purpose reservoirs in the Tennessee River Basin. The agency also owns and operates a number of fossil fuel and nuclear power plants throughout the Tennessee Valley. These plants depend on the TVA reservoir system for their condenser cooling water needs and dissipation of the waste heat generated from energy conversion. This paper reports on a one-dimensional model that has been developed for computation of water temperature in the TVA reservoir system. The model has been successfully used in evaluating the impact of incremental changes in meteorology on longitudinally distribution of water temperature in the reservoir system

  15. Modeling reservoir geomechanics using discrete element method : Application to reservoir monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alassi, Haitham Tayseer

    2008-09-15

    Understanding reservoir geomechanical behavior is becoming more and more important for the petroleum industry. Reservoir compaction, which may result in surface subsidence and fault reactivation, occurs during reservoir depletion. Stress changes and possible fracture development inside and outside a depleting reservoir can be monitored using time-lapse (so-called '4D') seismic and/or passive seismic, and this can give valuable information about the conditions of a given reservoir during production. In this study we will focus on using the (particle-based) Discrete Element Method (DEM) to model reservoir geomechanical behavior during depletion and fluid injection. We show in this study that DEM can be used in modeling reservoir geomechanical behavior by comparing results obtained from DEM to those obtained from analytical solutions. The match of the displacement field between DEM and the analytical solution is good, however there is mismatch of the stress field which is related to the way stress is measured in DEM. A good match is however obtained by measuring the stress field carefully. We also use DEM to model reservoir geomechanical behavior beyond the elasticity limit where fractures can develop and faults can reactivate. A general technique has been developed to relate DEM parameters to rock properties. This is necessary in order to use correct reservoir geomechanical properties during modeling. For any type of particle packing there is a limitation that the maximum ratio between P- and S-wave velocity Vp/Vs that can be modeled is 3 . The static behavior for a loose packing is different from the dynamic behavior. Empirical relations are needed for the static behavior based on numerical test observations. The dynamic behavior for both dense and loose packing can be given by analytical relations. Cosserat continuum theory is needed to derive relations for Vp and Vs. It is shown that by constraining the particle rotation, the S-wave velocity can be

  16. The Classification and Model of Coalbed Methane Reservoirs

    Institute of Scientific and Technical Information of China (English)

    SU Xianbo; LIN Xiaoying; SONG Yah; ZHAO Mengjun

    2004-01-01

    Coalbed methane has been explored in many basins worldwide for 30 years, and has been developed commercially in some of the basins. Many researchers have described the characteristics of coalbed methane geology and technology systematically. According to these investigations, a coalbed methane reservoir can be defined: "a coal seam that contains some coalbed methane and is isolated from other fluid units is called a coalbed methane reservoir".On the basis of anatomizafion, analysis, and comparison of the typical coalbed methane reservoirs, coalbed methane reservoirs can be divided into two classes: the hydrodynamic sealing coalbed methane reservoirs and the self-sealing coalbed methane reservoirs. The former can be further divided into two sub-classes: the hydrodynamic capping coalbed methane reservoirs, which can be divided into five types and the hydrodynamic driving coalbed methane reservoirs,which can be divided into three types. The latter can be divided into three types. Currently, hydrodynamic sealing reservoirs are the main target for coalbed methane exploration and development; self-sealing reservoirs are unsuitable for coalbed methane exploration and development, but they are closely related with coal mine gas hazards. Finally, a model for hydrodynamic sealing coalbed methane reservoirs is established.

  17. FEASIBILITY STUDY OF SEDIMENT FLUSHING FROM MOSUL RESERVOIR, IRAQ

    Directory of Open Access Journals (Sweden)

    Thair Mahmood Al-Taiee

    2013-05-01

    Full Text Available   The Feasibility of sediment flushing  from Mosul reservoir located northern iraq was conducted. Many up to date world criteria and indices for checking the efficiency of sediment flushing from reservoir which have been got through analyzing large amount of  data from many flushed reservoirs  in the world which were depended tested and applied in the present case study (Mosul Reservoir. These criteria and indices depend mainly on the hydrological , hydraulic and  topographical properties of the reservoirs in-addition to the operation plan of the reservoirs. They gave a good indication for checking the efficiency of the sediment flushing  process in the reservoirs. It was concluded that approximately the main criteria for the successful flushing sediment was  verified  in  Mosul  reservoir  such as  Sediment Balance Ratio   (SBR and the Long Term Capacity Ratio (LTCR,the shape factor  of reservoir (W/L and the hydraulic condition such as the percentage of (Qf/Qin and (Vf/Vin. This gave an indication that the processes of flushing sediment in Mosul reservoir is probably feasible and may be applied  in the future to maintain the water storage in the reservoir.

  18. Modelling of sediment transport in the reservoir during floods

    International Nuclear Information System (INIS)

    In this presentation author deals with the modelling of sediment transport in the reservoir river during floods on the Vah river, Kysuca river and Rajcianka river. It was concluded that: Decrease of the Hricov reservoir volume by 36% in 2000, thanks to flushing in 2002 only 26%; Sedimentation in reservoir prevails over the erosion; Reservoir sediments mainly from silt particles, less portions of sand and clay; Regression relations between discharge and suspended load discharge derived for inflow rivers - balance of sediment transport; During 1989-2000 suspended load inflow to reservoir 3,253,100 tonnes, sediment deposits 1,575,300 tonnes, and reservoir trap efficiency cca. 50%; Sedimentation of suspended load during normal situations almost on the whole reservoir area, increase of flow velocity at higher discharges can cause resuspension and erosion of reservoir deposits; The Hricov reservoir is proper for alternative ways of sediment removal - passing of inflow sediments through the reservoir in a turbulent suspension and reservoir flushing; It is recommended to continue in sediment transport monitoring

  19. Seismic response of concrete gravity dams with finite reservoir

    International Nuclear Information System (INIS)

    In most previous analyses of dam responses to earthquake ground motion, the upstream reservoir is assumed to be infinite in length and completely straight. The meandering nature of the river system, however, results in the creation of a finite length reservoir upstream of the dam structure. A study was carried out to examine the effects of the finite length of the reservoir on the dynamic behavior of the monolith. The effect of excitation of the far end of the boundary on the monolith's response is also of interest. The dam-foundation-reservoir system is modelled using a sub-structuring approach. The analysis is conducted in the frequency domain and utilizes the finite element technique. The water in the reservoir is assumed to be compressible, inviscid, and irrotational. The upstream reservoir is assumed to have a rectangular cross-section. It was found that the finite length reservoir assumption results in supplementary response peaks in the monolith's response. The finite reservoir length allows the reservoir to resonate both in horizontal and vertical directions. The magnitude and spacing of these supplementary response peaks are dependent on the length of the reservoir. The phase of the ground motion which affects the far end boundary of the reservoir was also found to have a significant effect on the dam monolith's response. 8 refs., 5 figs

  20. Mathematical simulation of oil reservoir properties

    International Nuclear Information System (INIS)

    The study and computational representation of porous media properties are very important for many industries where problems of fluid flow, percolation phenomena and liquid movement and stagnation are involved, for example, in building constructions, ore processing, chemical industries, mining, corrosion sciences, etc. Nevertheless, these kinds of processes present a noneasy behavior to be predicted and mathematical models must include statistical analysis, fractal and/or stochastic procedures to do it. This work shows the characterization of sandstone berea core samples which can be found as a porous media (PM) in natural oil reservoirs, rock formations, etc. and the development of a mathematical algorithm for simulating the anisotropic characteristics of a PM based on a stochastic distribution of some of their most important properties like porosity, permeability, pressure and saturation. Finally a stochastic process is used again to simulated the topography of an oil reservoir

  1. Mathematical simulation of oil reservoir properties

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, A. [Instituto Politecnico Nacional (SEPI-ESQIE-UPALM-IPN), Unidad Profesional Zacatenco, Laboratorio de Analisis Met., Edif. ' Z' y Edif. 6 planta baja., Mexico City c.p. 07300 (Mexico)], E-mail: adalop123@mailbanamex.com; Romero, A.; Chavez, F. [Instituto Politecnico Nacional (SEPI-ESQIE-UPALM-IPN), Unidad Profesional Zacatenco, Laboratorio de Analisis Met., Edif. ' Z' y Edif. 6 planta baja., Mexico City c.p. 07300 (Mexico); Carrillo, F. [Instituto Politecnico Nacional (CICATA-IPN, Altamira Tamaulipas) (Mexico); Lopez, S. [Instituto Mexicano del Petroleo - Molecular Engineering Researcher (Mexico)

    2008-11-15

    The study and computational representation of porous media properties are very important for many industries where problems of fluid flow, percolation phenomena and liquid movement and stagnation are involved, for example, in building constructions, ore processing, chemical industries, mining, corrosion sciences, etc. Nevertheless, these kinds of processes present a noneasy behavior to be predicted and mathematical models must include statistical analysis, fractal and/or stochastic procedures to do it. This work shows the characterization of sandstone berea core samples which can be found as a porous media (PM) in natural oil reservoirs, rock formations, etc. and the development of a mathematical algorithm for simulating the anisotropic characteristics of a PM based on a stochastic distribution of some of their most important properties like porosity, permeability, pressure and saturation. Finally a stochastic process is used again to simulated the topography of an oil reservoir.

  2. Innovative MIOR Process Utilizing Indigenous Reservoir Constituents

    Energy Technology Data Exchange (ETDEWEB)

    D. O. Hitzman; A. K. Stepp; D. M. Dennis; L. R. Graumann

    2003-03-31

    This research program is directed at improving the knowledge of reservoir ecology and developing practical microbial solutions for improving oil production. The goal is to identify indigenous microbial populations which can produce beneficial metabolic products and develop a methodology to stimulate those select microbes with nutrient amendments to increase oil recovery. This microbial technology has the capability of producing multiple oil-releasing agents. Experimental laboratory work is underway. Microbial cultures have been isolated from produced water samples. Comparative laboratory studies demonstrating in situ production of microbial products as oil recovery agents were conducted in sand packs with natural field waters with cultures and conditions representative of oil reservoirs. Field pilot studies are underway.

  3. Overspill avalanching in a dense reservoir network.

    Science.gov (United States)

    Mamede, George L; Araújo, Nuno A M; Schneider, Christian M; de Araújo, José Carlos; Herrmann, Hans J

    2012-05-01

    Sustainability of communities, agriculture, and industry is strongly dependent on an effective storage and supply of water resources. In some regions the economic growth has led to a level of water demand that can only be accomplished through efficient reservoir networks. Such infrastructures are not always planned at larger scale but rather made by farmers according to their local needs of irrigation during droughts. Based on extensive data from the upper Jaguaribe basin, one of the world's largest system of reservoirs, located in the Brazilian semiarid northeast, we reveal that surprisingly it self-organizes into a scale-free network exhibiting also a power-law in the distribution of the lakes and avalanches of discharges. With a new self-organized-criticality-type model we manage to explain the novel critical exponents. Implementing a flow model we are able to reproduce the measured overspill evolution providing a tool for catastrophe mitigation and future planning. PMID:22529343

  4. Overspill avalanching in a dense reservoir network

    CERN Document Server

    Mamede, G L; Schneider, C M; de Araújo, J C; Herrmann, H J

    2012-01-01

    Sustainability of communities, agriculture, and industry is strongly dependent on an effective storage and supply of water resources. In some regions the economic growth has led to a level of water demand which can only be accomplished through efficient reservoir networks. Such infrastructures are not always planned at larger scale but rather made by farmers according to their local needs of irrigation during droughts. Based on extensive data from the upper Jaguaribe basin, one of the world's largest system of reservoirs, located in the Brazilian semiarid northeast, we reveal that surprisingly it self-organizes into a scale-free network exhibiting also a power-law in the distribution of the lakes and avalanches of discharges. With a new self-organized-criticality-type model we manage to explain the novel critical exponents. Implementing a flow model we are able to reproduce the measured overspill evolution providing a tool for catastrophe mitigation and future planning.

  5. Oil Reservoir Production Optimization using Optimal Control

    DEFF Research Database (Denmark)

    Völcker, Carsten; Jørgensen, John Bagterp; Stenby, Erling Halfdan

    2011-01-01

    Practical oil reservoir management involves solution of large-scale constrained optimal control problems. In this paper we present a numerical method for solution of large-scale constrained optimal control problems. The method is a single-shooting method that computes the gradients using the...... adjoint method. We use an Explicit Singly Diagonally Implicit Runge-Kutta (ESDIRK) method for the integration and a quasi-Newton Sequential Quadratic Programming (SQP) algorithm for the constrained optimization. We use this algorithm in a numerical case study to optimize the production of oil from an oil...... reservoir using water ooding and smart well technology. Compared to the uncontrolled case, the optimal operation increases the Net Present Value of the oil field by 10%....

  6. Water coning in fractured basement reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Saad, S.E.D.M.; Darwich, T.D.; Asaad, Y.

    1995-11-01

    The problem of water coning in fractured basement reservoirs has been addressed in this work. The outcome of experimental and theoretical investigation to determine the critical production rate for single- and multi-fractured system, the capillary pressure effect, and the break-through time is presented. The results of the experimental work verify the presented theoretical relationship for different fluid viscosities, fracture angles, oil-water contacts (OWC), and rates for the case of single fracture system. The results also indicate that the capillary pressure effect may be generally neglected if the distance between the OWC and the fluid entry is sufficiently large compared to the capillary rise. The extension of the critical rate determination for a multi-fractured reservoir is also discussed. Finally, the main factors influencing the break-through time were investigated. The difference in viscosity between the oil and water phases has been fond to be the main factor affecting the breakthrough time.

  7. Toward optical signal processing using photonic reservoir computing.

    Science.gov (United States)

    Vandoorne, Kristof; Dierckx, Wouter; Schrauwen, Benjamin; Verstraeten, David; Baets, Roel; Bienstman, Peter; Van Campenhout, Jan

    2008-07-21

    We propose photonic reservoir computing as a new approach to optical signal processing in the context of large scale pattern recognition problems. Photonic reservoir computing is a photonic implementation of the recently proposed reservoir computing concept, where the dynamics of a network of nonlinear elements are exploited to perform general signal processing tasks. In our proposed photonic implementation, we employ a network of coupled Semiconductor Optical Amplifiers (SOA) as the basic building blocks for the reservoir. Although they differ in many key respects from traditional software-based hyperbolic tangent reservoirs, we show using simulations that such a photonic reservoir can outperform traditional reservoirs on a benchmark classification task. Moreover, a photonic implementation offers the promise of massively parallel information processing with low power and high speed. PMID:18648434

  8. Structural Geometry of a Sector of the Colorado River Delta, Baja California, Mexico, Based on Seismic Reflections

    Science.gov (United States)

    Chanes-Martínez, J. Juan; González-Escobar, Mario; Suárez-Vidal, Francisco; Gallardo-Mata, Clemente G.

    2014-07-01

    A structural study in the SW section of the Colorado River delta using seismic reflection data is presented. The study area is located along the Cerro Prieto transform fault, which extends from the northern Gulf of California through the Mexicali Valley and is an active fault within the Pacific-North American plate boundary zone. The research was supported by a database of five seismic profiles with a total length of 215 km, collected in the early 80's by Petróleos Mexicanos. The results show a high density of faults, most of which are buried by sediments. Within the Cerro Prieto fault zone, several faults were identified, such as: Palmas, Mesa, and Pangas Viejas, until now unknown. In addition, even though the Indiviso fault was investigated and superficially identify prior to this work, herein mapped at depth. West of the Cerro Prieto fault zone lies the Las Tinajas basin, bound by the Dunas and Saldaña faults and by the Montague basin to the southeast. The deformation zone along the plate boundary is 18-km-wide, stretching from the Cerro Prieto fault in the east to the Pangas Viejas fault in the west. The orientations of the faults are NW-SE, and if projected from the southern side of the Sierra Cucapah southward, the faults tend to join the Cerro Prieto fault. In the Las Tinajas basin, the acoustic basement is deeper than 5,000 m. Some of the largest vertical displacements generated by the 2010 7.2-Mw El Mayor-Cucapah earthquake occurred southeast of the epicenter and coincided with the location of the Pangas Viejas Fault, which is buried by sediments. Before this event, seismic activity was very low, and no structures were known in the area. In this paper, we demonstrate that there are at least seven major faults that may now pose a high seismic hazard.

  9. Coalbed methane reservoir characterization using magnetic susceptibility

    Science.gov (United States)

    Ivakhnenko, Aleksandr; Makhatova, Meruyert; Kalbekov, Arkhat; Baibussinova, Zhanar; Moldagereyeva, Anel

    2016-04-01

    This research describes a study of the dependence of the magnetic susceptibility (MS) and permeability as a new approach for coalbed methane (CBM) reservoir characterization. Experimental measurements were undertaken in coal cores from Kazakhstan (Karaganda Basin). The well sections containing coal are the area of high interest where regular deposition of sandstone, shale and coal is observed. The MS measurements were made by the core logging sensor with the sensitive area of the probe providing volume magnetic susceptibility values. Permeability has been determined by air permeameter. Both magnetic susceptibility and permeability have been measured at the same points. The obtained values of permeability and magnetic susceptibility exhibit the predicted pattern of deposition of reservoir rocks. Coal reservoirs generally is spaced between shale layers with extremely high MS values and highly low permeability. Sandstone with shale interlayers tends to be a transition area between shale and coal. Such tendency appears within several sections. The experimental results showed a strong correspondence between measured magnetic susceptibility and permeability of coal core samples. Therefore, inverse proportionality between magnetic susceptibility and permeability is observed. Generally, the high values of magnetic susceptibility correspond to low permeability, likewise the low diamagnetic MS values comply with high permeability of production zones. In a point of fact, linear proportionality appears as well due to fractures. In this case, permeability must be recalculated in relation to degree of fracturing. Magnetic susceptibility results could sometimes be affected by small content of ferrimagnetic minerals that resulted in high MS values. However, MS data demonstrated good correlations with permeability. The application of magnetic susceptibility values for coalbed methane reservoir characterization could be a non-destructive and rapid method potentially used in both

  10. The North Sea reservoir chalk characterization

    OpenAIRE

    Kallesten, Emanuela

    2015-01-01

    A significant amount of the hydrocarbon production in the North Sea is related to chalk reservoirs. Since 1969, the chalk play remains one of the most important oil sources in Norway. With the initial expected recovery factor 17%, development in technologies and methods contributed to a substantial increase in oil recovery to an approximately 40%. Much of the reserves in place are yet to be extracted, and secondary and tertiary recovery methods need to advance in order to mobilize the remaini...

  11. NMPC for Oil Reservoir Production Optimization

    DEFF Research Database (Denmark)

    Völcker, Carsten; Jørgensen, John Bagterp; Thomsen, Per Grove;

    2011-01-01

    In this paper, we use nonlinear model predictive control (NMPC) to maximize secondary oil recovery from an oil reservoir by controlling two-phase subsurface porous flow using adjustable down-hole control valves. The resulting optimal control problem is nonlinear and large-scale. We solve this...... used for sensitivity computations. We report computational experiences and oil recovery improvements for a standard test case....

  12. Optimal Carbon Sequestration Policies in Leaky Reservoirs

    OpenAIRE

    Jean-Marie, Alain; MOREAUX Michel; Tidball, Mabel

    2014-01-01

    We study in this report a model of optimal Carbon Capture and Storage in which the reservoir of sequestered carbon is leaky, and pollution eventually is released into the atmosphere. We formulate the social planner problem as an optimal control program and we describe the optimal consumption paths as a function of the initial conditions, the physical constants and the economical parameters. In particular, we show that the presence of leaks may lead to situations which do not occur otherwise, ...

  13. Optimal Hedging Rule for Reservoir Refill Operation

    Science.gov (United States)

    Wan, W.; Zhao, J.; Lund, J. R.; Zhao, T.; Lei, X.; Wang, H.

    2015-12-01

    This paper develops an optimal reservoir Refill Hedging Rule (RHR) for combined water supply and flood operation using mathematical analysis. A two-stage model is developed to formulate the trade-off between operations for conservation benefit and flood damage in the reservoir refill season. Based on the probability distribution of the maximum refill water availability at the end of the second stage, three zones are characterized according to the relationship among storage capacity, expected storage buffer (ESB), and maximum safety excess discharge (MSED). The Karush-Kuhn-Tucker conditions of the model show that the optimality of the refill operation involves making the expected marginal loss of conservation benefit from unfilling (i.e., ending storage of refill period less than storage capacity) as nearly equal to the expected marginal flood damage from levee overtopping downstream as possible while maintaining all constraints. This principle follows and combines the hedging rules for water supply and flood management. A RHR curve is drawn analogously to water supply hedging and flood hedging rules, showing the trade-off between the two objectives. The release decision result has a linear relationship with the current water availability, implying the linearity of RHR for a wide range of water conservation functions (linear, concave, or convex). A demonstration case shows the impacts of factors. Larger downstream flood conveyance capacity and empty reservoir capacity allow a smaller current release and more water can be conserved. Economic indicators of conservation benefit and flood damage compete with each other on release, the greater economic importance of flood damage is, the more water should be released in the current stage, and vice versa. Below a critical value, improving forecasts yields less water release, but an opposing effect occurs beyond this critical value. Finally, the Danjiangkou Reservoir case study shows that the RHR together with a rolling

  14. Nuclear stimulation of oil-reservoirs

    International Nuclear Information System (INIS)

    Underground nuclear explosions in the Hoggar nuclear test site have shown that the geological effects may increase the production of oil or gas reservoirs. By studying the permanent liquid flow-rate with approximate DUPUIT's equation, or with a computer code, it is shown that the conventional well flow-rate may be increased by a factor between 3 and 50, depending on the medium and explosion conditions. (author)

  15. Development alternatives for the Reforma area reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Garaicochea, F.; Acuna, R.A.

    1976-10-01

    In the states of Chiapas and Tabasco more promise has been developed in the matter of petroleum production than any in Mexico in the last several decades. The reservoirs, locally in linear anticlinal structures oriented north to southeast belong to formations of the Cretaceous. They possess notable thickness, in many cases more than 200 m. The reserves of the area are still indeterminate since what is unknown is the volume of hydrocarbons which are stored or the recoveries which, to date, are contributed by the low development of the natural producing mechanisms or the artificial form of producing. The principal development alternatives susceptible to application in the reservoirs of the Reforma area are pointed out in a general way. The subjects discussed include (1) geology; (2) petrography; (3) fluid properties; (4) behavior of the reservoirs; (5) primary behavior without water entry; (6) primary behavior with hydraulic energy; (7) behavior with water injection; and (8) behavior with gas injection. Although this analysis is essentially qualitative, it nevertheless will permit formulating the plans which are fundamental to the subsequent development of more detailed studies. (34 refs.)

  16. Improving reservoir conformance using gelled polymer systems

    Energy Technology Data Exchange (ETDEWEB)

    Green, D.W.; Willhite, G.P.

    1993-04-09

    The general objectives are to (1) to identify and develop gelled polymer systems which have potential to improve reservoir conformance of fluid displacement processes, (2) to determine the performance of these systems in bulk and in porous media, and (3) to develop methods to predict the capability of these systems to recover oil from petroleum reservoirs. This work focuses on three types of gel systems - an aqueous polysaccharide (KUSPI) system that gels as a function of pH, the chromium-based system where polyacrylamide and xanthan are crosslinked by CR(III) and an organic crosslinked system. Development of the KUSPI system and evaluation and identification of a suitable organic crosslinked system will be done. The laboratory research is directed at the fundamental understanding of the physics and chemistry of the gelation process in bulk form and in porous media. This knowledge will be used to develop conceptual and mathematical models of the gelation process. Mathematical models will then be extended to predict the performance of gelled polymer treatments in oil reservoirs. Accomplishments for this period are presented for the following tasks: development and selection of gelled polymer systems, physical and chemical characterization of gel systems; and mathematical modeling of gel systems.

  17. Sources and subsurface reservoirs of lunar volatiles

    International Nuclear Information System (INIS)

    Estimates are presented for volumes and compositions of lunar volatiles in proposed subsurface traps, and possibilities are discussed for such shallow gas reservoirs. Crater fillings could serve as porous and permeable gas reservoirs, as could magma chambers and conduits. Terrestrial-analog structural domes covered by a less porous and less permeable cap might exist, as well as stratigraphic 'pinch-out' traps. Likewise, fault-related traps might also exist. There are three sources for the gas that might be found in such reservoirs. Firstly, solar wind implanted H, He and other noble gases, as well as N, C, and O, are known to exist in significant quantities in the lunar regolith. Secondly, volcanic outgassing could produce CO, CO2, CH4, He, N2, NH3, H20, and H2S. Finally, radioactive decay in the lunar interior is thought to produce He, Rn, and Ar. The geologic systems affecting regolith outgassing and trapping may be of pratical importance for in situ lunar resource utilization. 48 refs

  18. Geomechanical Properties of Unconventional Shale Reservoirs

    Directory of Open Access Journals (Sweden)

    Mohammad O. Eshkalak

    2014-01-01

    Full Text Available Production from unconventional reservoirs has gained an increased attention among operators in North America during past years and is believed to secure the energy demand for next decades. Economic production from unconventional reservoirs is mainly attributed to realizing the complexities and key fundamentals of reservoir formation properties. Geomechanical well logs (including well logs such as total minimum horizontal stress, Poisson’s ratio, and Young, shear, and bulk modulus are secured source to obtain these substantial shale rock properties. However, running these geomechanical well logs for the entire asset is not a common practice that is associated with the cost of obtaining these well logs. In this study, synthetic geomechanical well logs for a Marcellus shale asset located in southern Pennsylvania are generated using data-driven modeling. Full-field geomechanical distributions (map and volumes of this asset for five geomechanical properties are also created using general geostatistical methods coupled with data-driven modeling. The results showed that synthetic geomechanical well logs and real field logs fall into each other when the input dataset has not seen the real field well logs. Geomechanical distributions of the Marcellus shale improved significantly when full-field data is incorporated in the geostatistical calculations.

  19. Permeability restoration in underground disposal reservoirs

    International Nuclear Information System (INIS)

    The aim of the research performed was to explore methods of permeability restoration in underground disposal reservoirs that may improve the receptive capacity of a well to a level that will allow continued use of the disposal zone without resorting to elevated injection pressures. The laboratory investigation employed a simulated open-hole completion in a disposal well wherein the entire formation face is exposed to the well bore. Cylindrical core samples from representative reservoir rocks through which a central vertical opening or borehole had been drilled were injected with a liquid waste obtained from a chemical manufacturing plant. This particular waste material was found to have a moderate plugging effect when injected into samples of reservoir rocks in a prior study. A review was made of the chemical considerations that might account for the reduction of permeability in waste injection. Purpose of this study was to ascertain the conditions under which the precipitation of certain compounds might occur in the injection of the particular waste liquid employed. A summary of chemical calculations is contained in Appendix B. The data may be useful in the treatment of wastes prior to injection and in the design of restoration procedures where analyses of waste liquids and interstitial materials are available. The results of permeability restoration tests were analyzed mathematically by curve-fitting techniques performed by a digital computer. A summary of the analyses is set forth in the discussion of test results and examples of computer printouts are included in Appendix A

  20. Influence of reservoir stress path on deformation and permeability of weakly cemented sandstone reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Ruistuen, H.; Teufel, L.W.; Rhett, D.

    1996-12-31

    The influence of production-induced changes in reservoir stress state on compressibility and permeability of weakly cemented sandstones has been analyzed. Laboratory experiments simulating reservoir depletion have been conducted for the full range of stress paths that a reservoir may follow. Samples were loaded by reducing the pore pressure and controlling the confining pressure according to the desired stress path from initial reservoir conditions. The results show that compressibility of weakly cemented sandstones are stress path dependent. Compressibilities measured under uniaxial strain conditions, or a stress path with a K value lower than the one associated with uniaxial strain, are more than twice the corresponding value found under hydrostatic loading conditions. In contrast, matrix permeability measured in the maximum stress direction show no significant stress path dependence. Independently of stress path, the observed permeability reductions fall within the general trend expected for a sedimentary rock of relatively high initial permeability. A significant permeability decrease was only observed as the shear stress exceeded the yield limit of the rock, probably due to both mobilization of fine arains and an increase in tortuosity due to collapse of pore space. Results of this study suggest that stress path dependent properties of weakly cemented sandstones is a consequence of the heterogeneous nature of the sedimentary rock. Material properties are affected by grain-scale inelastic deformation processes and the pattern of these deformation processes is primarily controlled by reservoir stress path.