Plutons and accretionary episodes of the Klamath Mountains, California and Oregon

Science.gov (United States)

Irwin, William P.; Wooden, Joseph L.

1999-01-01

The Klamath Mountains consist of various accreted terranes and include many plutons that range in composition from gabbro to granodiorite. Some of the plutons (preaccretionary plutons) were parts of terranes before the terranes accreted; others (accretionary plutons) intruded during or after the accretion of their host terrane(s). This report attempts to (1) graphically illustrate how the Klamath Mountains grew by the accretion of allochthonous oceanic terranes during early Paleozoic to Cretaceous times, (2) identify the plutons as either preaccretionary or accretionary, and (3) genetically relate the plutonic intrusions to specific accretionary episodes. The eight accretionary episodes portrayed in this report are similar to those shown by Irwin and Mankinen (1998) who briefly described the basis for the timing of the episodes and who illustrated the ~110 degrees of clockwise rotation of the Klamath Mountains since Early Devonian time. Each episode is named for the accreting terrane. In all episodes (Figs. 1-8), the heavy black line represents a fault that separates the accreting oceanic rocks on the left from earlier accreted terranes on the right. The preaccretionary plutons are shown within the accreting oceanic crustal rocks to the left of the heavy black line, and the accretionary plutons in most instances are shown intruding previously accreted terranes to the right. Episodes earlier than the Central Metamorphic episode (Fig. 1), and that may have been important in the formation of the early Paleozoic nucleous of the province (the Eastern Klamath terrane), are not known. The 'Present Time' distribution of the accreted terranes and plutons is shown at a large scale in Figure 9. The schematic vertical section (Fig. 10) depicts the terranes as a stack of horizontal slabs that include or are intruded by vertical plutons. Note that at their base the ~170 Ma preaccretionary plutons of the Western Hayfork subterrane are truncated by the ~164 Ma Salt Creek

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.

Uruguay mining Inventory: geochemical prospecting results of Cerro de las Cuentas mapping

International Nuclear Information System (INIS)

Spangenberg, J.; Filippini, J.

1986-01-01

This work is about the geochemical prospecting carried out into the Uruguay mining inventory framework. In this case the survey was in Cerro de las Cuentas mapping. Cerro Largo department. Scale 1 / 50000.

Cerro Baúl: un enclave wari en interacción con Tiwanaku

OpenAIRE

Williams, Patrick Ryan; Isla, Johny A.; Nash, Donna J.

2012-01-01

Cerro Baul: A Wari Enclave Interacting with TiwanakuWari expansion to the extreme south of Peru is a phenomenon whose study began 20 years ago, with the discovery of a great arquitectonic complex at Cerro Baul. The excavations undertaken in the last 3 years have revealed that Cerro Baul was more than a military fortress; it was the most important political and religious center that Wari established in the only region where there is direct evidence of interaction with Tiwanaku, the altiplano s...

Petrology and radiogeology of the Stripa pluton

International Nuclear Information System (INIS)

Wollenberg, Harold; Flexser, Steve; Andersson, Lennart

1980-01-01

To better define the character of the rock encompassing the thermomechanical and hydrological experiments at the Stripa mine in central Sweden, and to help determine the size of the Stripa pluton, detailed studies were conducted of the petrology and radiogeology of the quartz monzonite and adjacent rocks. Petrologic studies emphasized optical petrography, with supplementary X-ray diffraction, X-ray fluorescence and microprobe analyses. Radiogeologic investigations were based primarily on surface and underground gamma-ray spectrometric measurements of uranium, thorium and potassium, supplemented by laboratory gamma spectrometric analyses and fission-track radiographic determinations of the locations and abundance of uranium in the rock matrix. Both the quartz monzonite and the metavolcanic leptite which it intruded are strongly fractured. Two stages of fracture filling are evident; an earlier stage encompassing quartz, sericite, feldspar, epidote, and chlorite, and a later stage dominated by carbonate minerals. The Stripa quartz monzonite is chemically and mineralogically distinct from other plutons in the region. Muscovite is the predominant mica in the quartz monzonite; biotite has been altered to chlorite, hornblende is absent, and accessory minerals are scarce. In contrast, in other plutons in the Stripa region biotite and hornblende are prominent mafic minerals and accessory minerals are abundant. The Stripa quartz monzonite is also considerably more radioactive than the leptite and other plutons in the region. Uranium and thorium abundances are both- 30 ppm, considerably higher than in 'normal' granitic rocks where the thorium-to-uranium ratio generally exceeds 2. Potassium-argon dating of muscovite from the Stripa quartz monzonite indicates that this rock may be older, at 1691 million years than granitic rock of the neighboring Gusselby and Kloten massifs, whose ages, based on K-Ar dating of biotite, are respectively 1604 and 1640 m.y. Heat flow and heat

Petrology and radiogeology of the Stripa pluton

Energy Technology Data Exchange (ETDEWEB)

Wollenberg, Harold; Flexser, Steve; Andersson, Lennart

1980-12-01

To better define the character of the rock encompassing the thermomechanical and hydrological experiments at the Stripa mine in central Sweden, and to help determine the size of the Stripa pluton, detailed studies were conducted of the petrology and radiogeology of the quartz monzonite and adjacent rocks. Petrologic studies emphasized optical petrography, with supplementary X-ray diffraction, X-ray fluorescence and microprobe analyses. Radiogeologic investigations were based primarily on surface and underground gamma-ray spectrometric measurements of uranium, thorium and potassium, supplemented by laboratory gamma spectrometric analyses and fission-track radiographic determinations of the locations and abundance of uranium in the rock matrix. Both the quartz monzonite and the metavolcanic leptite which it intruded are strongly fractured. Two stages of fracture filling are evident; an earlier stage encompassing quartz, sericite, feldspar, epidote, and chlorite, and a later stage dominated by carbonate minerals. The Stripa quartz monzonite is chemically and mineralogically distinct from other plutons in the region. Muscovite is the predominant mica in the quartz monzonite; biotite has been altered to chlorite, hornblende is absent, and accessory minerals are scarce. In contrast, in other plutons in the Stripa region biotite and hornblende are prominent mafic minerals and accessory minerals are abundant. The Stripa quartz monzonite is also considerably more radioactive than the leptite and other plutons in the region. Uranium and thorium abundances are both- 30 ppm, considerably higher than in "normal" granitic rocks where the thorium-to-uranium ratio generally exceeds 2. Potassium-argon dating of muscovite from the Stripa quartz monzonite indicates that this rock may be older, at 1691 million years than granitic rock of the neighboring Gusselby and Kloten massifs, whose ages, based on K-Ar dating of biotite, are respectively 1604 and 1640 m.y. Heat flow and heat

Petrology of Terra Nova pluton, Brazil, and associated ultrapotassic dykes

International Nuclear Information System (INIS)

Silva Filho, A.F. da; Thompson, R.N.; Leat, P.T.

1987-01-01

The Upper Precambrian Terra Nova Pluton, situated 550 Km inland from Recife, Brazil, is 220 Km 2 in area and intrudes deformed metasedimentary rocks of the Pianco-Alto Brigida Mobile Belt. The Pluton shows complex petrological relationships. It consists of subalkaline quartz-monzonites and quartz-syenites, and the major minerals are K-feldspars, albite, hornblende, and quartz. The pluton is intermediate in composition (SiO 2 = 58.9-65.6 wt%, MgO=0.9-3.7 wt%) and is dominantly potassic (K 2 O=3.3-5.6 wt %; K 2 O/Na 2 O=0.9-1.8). Ba (up to 2.300 ppm) and Sr (up to 1,100 ppm) are abundant in the rocks, and LREE are enriched relative to HREE (La N /Lu N = 25.6-43.2). There is no significant Eu Anomaly. Rounded autoliths within the pluton are similar, but more mafic in composition (SiO 2 =54.6-57.5 wt %; MgO=4.9-6.4 wt %). A suite of dykes cut pluton and the surrounding country rocks. These dykes are varied in composition, encompassing most of the chemical range shown by the pluton and associated autoliths. The dykes are holocrystalline, peralkaline, and strongly enriched in both K 2 O(K 2 O=5.3-11.4 wt %) and Ba (Ba=2,400 ppm-10,500 ppm), which are considered to be magmatic abundances. The dykes have similar REE and other trace elements and ratios to the autoliths and plutonic rocks, and the dykes and the pluton are thought to be chemically related. The Terra Nova Pluton records the fractionation of mantle-derived ultrapotassic magma from mafic to intermediate compositions. (author) [pt

The Solarya Volcano-Plutonic Complex (NW Turkey): Petrography, Petrogenesis and Tectonic Implications

Science.gov (United States)

Ünal, Alp; Kamacı, Ömer; Altunkaynak, Şafak

2014-05-01

The post collisional magmatic activity produced several volcano-plutonic complexes in NW Anatolia (Turkey) during the late Oligocene- Middle Miocene. One of the major volcano-plutonic complexes, the Solarya volcano-plutonic complex is remarkable for its coeval and cogenetic plutonic (Solarya pluton), hypabysal and volcanic rocks of Early Miocene (24-21 Ma) age. Solarya pluton is an epizonal pluton which discordantly intruded into metamorphic and nonmetamorphic basement rocks of Triassic age. It is a N-S trending magmatic body covering an area of 220 km2,approximatelly 20 km in length and 10 km in width. Based on the field and petrographic studies, three main rock groups distinguished in Solarya pluton; K-feldspar megacrystalline granodiorite, microgranite-granodiorite and haplogranite. Porphyritic and graphic-granophyric textures are common in these three rock groups. Pluton contains magmatic enclaves and syn-plutonic dykes of dioritic composition. Hypabyssal rocks are represented by porphyritic microdiorite and porphyritic quartz-diorite. They form porphyry plugs, sheet inrusions and dykes around the pluton. Porphyrites have microcrystalline-cryptocrystalline groundmass displaying micrographic and granophyric textures. Petrographically similar to the hypabyssal rocks, volcanic rocks are formed from andesitic and dasitic lavas and pyroclastic rocks. Plutonic, hypabyssal and volcanic rocks of Solarya volcano-plutonic complex show similar major-trace element and Sr-Nd-Pb isotopic compositions, indicating common magmatic evolution and multicomponent melt sources including mantle and crustal components. They are mainly metaluminous, medium to high-K calc alkaline rocks and display enrichment in LILE and depletion in Nb, Ta, P and Ti. They have initial 87Sr/86Sr values of 0.70701- 0.70818 and 143Nd/144Nd values of 0.51241-0.51250. These geochemical characteristics and isotopic signatures are considered to reflect the composition of the magmas derived from a

Overview of Cerro Prieto studies

Energy Technology Data Exchange (ETDEWEB)

Lippmann, M.J.

1983-01-01

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

Tipología del plutón de Campanario-La Haba: implicaciones petrogenéticas

OpenAIRE

Alonso Olazabal, Ainhoa; Aranguren, A.; Carracedo Sánchez, Manuel; Larrea Bilbao, F. J.

1996-01-01

The Campanario-La Haba pluton is located in the suothern part of the Central-Iberian Zone. It is a coarse-grained 5 type granitoid with cordierite. Typologicaly, this pluton is a peraluminous granitoid , CCA type. Mineralogy and petrologycally, the Campanario-La Haba pluton is closer to the Central Extremadura Bath olith ( Cabeza de Araya type) than to the granitic unit of the Los Pedrodres Batholith (Sta. Eufemia, El Guijo, Cerro Mogabar, Cardeña)

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

Science.gov (United States)

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

2016-11-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1982-10-01

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

Hydrothermal convection and uranium deposits in abnormally radioactive plutons

International Nuclear Information System (INIS)

1978-09-01

Hydrothermal uranium deposits are often closely associated with granites of abnormally high uranium content. We have studied the question whether the heat generated within such granites can cause fluid convection of sufficient magnitude to develop hydrothermal uranium deposits. Numerical models of flow through porous media were used to calculate temperatures and fluid flow in and around plutons similar to the Conway Granite, New Hampshire, i.e. with a halfwidth of 17 km, a thickness of 6.25 km, and with a uniform internal heat generation rate of 20 x 10 -13 cal/cm 3 -sec. Fluid convection was computed for plutons with permeabilities between 0.01 and 5 millidarcies (1 x10 -13 cm 2 to 5 x 10 -11 cm 2 . Flow rates and the size and location of convection cells in and around radioactive plutons like the Conway Granite were found to depend critically on the permeability distribution within the pluton and in adjacent country rocks. The depth of burial, the distribution of heat sources within the pluton, and small rates of heat generation in the country rock are only of minor importance. Topographic relief is unlikely to effect flow rates significantly, but can have a major influence on the distribution of recharge and discharge areas. Within a few million years, the mass of water transported by steady state convection through such radioactive plutons can equal the mass of water which can convect through them during initial cooling from magmatic temperatures. If the permeability in a Conway-type pluton is on the order of 0.5 millidarcies, the rate of fluid convection is probably sufficient to develop a hydrothermal ore deposit containing 10,000 tons of uranium in a period of two million years. Such a uranium deposit is most likely to develop in an area of strong upwelling or strong downwelling flow

Geology and geochemistry of Pelagatos, Cerro del Agua, and Dos Cerros monogenetic volcanoes in the Sierra Chichinautzin Volcanic Field, south of México City

Science.gov (United States)

Agustín-Flores, Javier; Siebe, Claus; Guilbaud, Marie-Noëlle

2011-04-01

This study focuses on the geology and geochemistry of three closely-spaced monogenetic volcanoes that are located in the NE sector of the Sierra Chichinautzin Volcanic Field near México City. Pelagatos (3020 m.a.s.l.) is a small scoria cone (0.0017 km 3) with lava flows (0.036 km 3) that covered an area of 4.9 km 2. Cerro del Agua scoria cone (3480 m.a.s.l., 0.028 km 3) produced several lava flows (0.24 km 3) covering an area of 17.6 km 2. Dos Cerros is a lava shield which covers an area of 80.3 km 2 and is crowned by two scoria cones: Tezpomayo (3080 m.a.s.l., 0.022 km 3) and La Ninfa (3000 m.a.s.l., 0.032 km 3). The eruptions of Cerro del Agua and Pelagatos occurred between 2500 and 14,000 yr BP. The Dos Cerros eruption took place close to 14,000 yr BP as constrained by radiocarbon dating. Rocks from these three volcanoes are olivine-hypersthene normative basaltic andesites and andesites with porphyritic, aphanitic, and glomeroporphyritic textures. Their mineral assemblages include olivine, clinopyroxene, and orthopyroxene phenocrysts (≤ 10 vol.%) embedded in a trachytic groundmass which consists mainly of plagioclase microlites and glass. Pelagatos rocks also present quartz xenocrysts. Due to their high Cr and Ni contents, and high Mg#s, Pelagatos rocks are considered to be derived from primitive magmas, hence the importance of this volcano for understanding petrogenetic processes in this region. Major and trace element abundances and petrography of products from these volcanoes indicate a certain degree of crystal fractionation during ascent to the surface. However, the magmas that formed the volcanoes evolved independently from each other and are not cogenetically related. REE, HFSE, LILE, and isotopic (Sr, Nd, and Pb) compositions point towards a heterogeneous mantle source that has been metasomatized by aqueous/melt phases from the subducted Cocos slab. There is no clear evidence of important crustal contributions in the compositions of Pelagatos and

Livre mercado

Directory of Open Access Journals (Sweden)

Müller, Lúcia Helena Alves

2003-01-01

Full Text Available Este artigo é resultado de uma etnografia que foi realizada junto ao mercado de ações brasileiro. Através da análise do funcionamento do pregão da bolsa de valores de São Paulo, das diferentes instituições financeiras que conformam este mercado e das trajetórias dos profissionais neste universo, busco demonstrar como são produzidas as condições sociais para a existência de um espaço de trocas que tem como princípio ordenador e legitimador o modelo teórico do mercado perfeito, formulado pela escola econômica neoclássica

Optical atmospheric extinction over Cerro Paranal

NARCIS (Netherlands)

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

2011-01-01

Aims. The present study was conducted to determine the optical extinction curve for Cerro Paranal under typical clear-sky observing conditions, with the purpose of providing the community with a function to be used to correct the observed spectra, with an accuracy of 0.01 mag airmass-1.

Constraints on the depth of generation and emplacement of a magmatic epidote-bearing quartz diorite pluton in the Coast Plutonic Complex, British Columbia

Science.gov (United States)

Chang, J.M.; Andronicos, C.L.

2009-01-01

Petrology and P-T estimates indicate that a magmatic epidote-bearing quartz diorite pluton from Mt. Gamsby, Coast Plutonic Complex, British Columbia, was sourced at pressures below ???1.4 GPa and cooled nearly isobarically at ???0.9 GPa. The P-T path indicates that the magma was within the stability field of magmatic epidote early and remained there upon final crystallization. The pluton formed and crystallized at depths greater than ???30 km. REE data indicate that garnet was absent in the melting region and did not fractionate during crystallization. This suggests that the crust was less than or equal to ???55 km thick at 188 Ma during the early phases of magmatism in the Coast Plutonic Complex. Late Cretaceous contractional deformation and early Tertiary extension exhumed the rocks to upper crustal levels. Textures of magmatic epidote and other magmatic phases, combined with REE data, can be important for constraining the P-T path followed by magmas. ?? 2009 Blackwell Publishing Ltd.

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

Energy Technology Data Exchange (ETDEWEB)

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

2005-06-01

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

Analysis on uranium metallogenetic conditions of granite pluton in Ulan Uzhur

International Nuclear Information System (INIS)

Lu Yaozu

2014-01-01

Qimantage area in Qinghai province is one of the important exploration areas in the present China, Ulan Uzhur complex pluton, located in the compound tectonic magmatic belt of Qimantage, is the main cluster area with uranium mineralization. This paper describes the petrochemical, geochemical, petrophysical and Heishan uranium deposit mineralization characteristics of rocks formed at the different tectonic-magmatic cycles in Ulan Uzhur complex pluton. Uranium metallogenic conditions in Ulan Uzhur complex pluton were analyzed from uranium source, magmatic activity and structure. The research shew that the Ulan Uzhur complex pluton has the petrochemical characteristics of uranium rock and Cisuralian monzonitic granite has the most significant relationship to uranium mineralization, it has the characteristics of high background radiation, many anomalies and pronounced ore-control structure, Heishan uranium deposit was controlled by factors such as pronounced northeast and the northwest structure and alteration. To conclude, Ulan Uzhur complex pluton possesses good uranium metallogenic prospect. (author)

Geological map of Uruguay Esc 1,100,000. Cerro Partido Sheet F-24

International Nuclear Information System (INIS)

Diaz, R; Albanell, H.; Bossi, J.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Cerro Partido) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils. The area corresponding to the Cerro Partido fotoplano is located in the orogenic belt or Don Feliciano belt

Miscellaneous investigations series: Bedrock geologic map of the Lone Mountain pluton area, Esmeralda County, Nevada

International Nuclear Information System (INIS)

Maldonado, F.

1984-01-01

The joint attitudes were measured in the field and plotted on aerial photos at a scale of 1:24,000. The pluton is intensely jointed, primarily as a result of cooling and movement of the magma within a northwest-trending stress field. Foliation, in general, is poorly developed, and quality varies from area to area, but it is best developed close to the contacts with the metasedimentary rocks. A prominent northwest foliation direction was observed that parallels the northwest elongation of the exposed pluton. Faults in the pluton are difficult to identify because of the homogeneity of the rock. Several faults were mapped in the northern part of the area where they have a northeast trend and intersect the northwest-trending lamprophyre dikes with little apparent displacement. A major fault that bounds the northern part of the pluton is downthrown to the north and strikes northeast. This fault offsets the alluvium, the metasedimentary rocks, and the pluton and forms fault scraps as high as 10 m. Aeromagnetic data (US Geological Survey, 1979) suggest the following: (1) the local magnetic highs in the central part of the Lone Mountain pluton are probably related to topographic highs (peaks) where the flight lines are closer to the pluton; (2) a magnetic low in the northeastern part of Lone Mountain coincides with the pluton-country rock contact, which may be very steep; (3) the contours for the southwestern part of the mapped area indicate that the pluton-country rock contact is not as steep as that in the northeastern part and that the pluton probably coalesces at depth with the Weepah pluton, a pluton exposed south of the mapped area; and (4) the contours for the area of the Lone Mountain pluton express a northwest-trending gradient that parallels the northwest elongation of the Lone Mountain pluton and the northwest-trending stress field. 10 refs

Some geomorphological features of the Orhaneli Pluton: Implications for denudation history

Directory of Open Access Journals (Sweden)

Ahmet Evren ERGİNAL

2008-12-01

Full Text Available The granitic intrusions of the variable age of cooling, size and mineral composition are widely exposed in the northwest Anatolia, Turkey. The nearly circular Orhaneli Pluton emplaced during the Early Eocene with some 15 km in diameter, is one of such plutonic bodies. Geomorphological features of the pluton are discussed here with special emphasis given on the denudation history. To this end, evidence from two isolated Inselberglike hills as remnants of roof rocks in the centre of the pluton and episodically emergence of granite landforms of etch origin after unroofing process were investigated. Field data reveal the absence of granodiorite clasts within Early to Middle Miocene lacustrine deposits in the north of the pluton, implying that the pluton might not have been exposure prior to Upper Miocene as a whole. After the first exposure, the granite landforms, such as boulders, corestones and tors constituting sound evidence of an etch origin, became exposure by continual removing of regolith cover by surficial runoff. These forms of various scale were formed at first by subsurface weathering and shaped by surficial weathering processes after any stages of removal of the regolith cover. Drainage segments accounted for removal of regolith is mostly structurally controlled defined by NW-SE, NE-SW and N-S-aligned fracture systems.

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

Science.gov (United States)

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

2016-10-01

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

Los mercados financieros

OpenAIRE

Franco Bendeck, Henry David; Guzmán Salazar, Laura Steffi

2017-01-01

En este documento el lector encontrará una visión general y un punto de partida sobre el funcionamiento de los mercados financieros de dinero y capitales, abordando la teoría en cuanto a la estructura y funcionamiento del sistema de valores intercambiario, además de aspectos como la psicología de sus participantes y la actualidad de algunos de los mercados muy poco desarrollados como el caso de los latinoamericanos. Estos aspectos hacen parte del contexto de inversión en los mercados, e...

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.

Geochemical characteristics and genesis of Baiyun pluton in southern Zhuguangshan mountain

International Nuclear Information System (INIS)

Zhang Shanguo; Huang Guolong; Fu Shuncheng; Wang Xiaodong; Xu Lili; Shen Weizhou

2011-01-01

Located in the east-central of the southern Zhuguangshan complex pluton, Baiyun pluton is an important uranium producing pluton. In lithology, it is coarse grain black mica granite. In major elements, the pluton is with rich silicon (SiO 2 average for 73.47%), rich aluminum (A/CNK value average 1.09) and high ratio of K 2 O/Na 2 O (average for 1.99). It is rich in large-ion trace elements Rb, Th, but poor in Ba, Sr, Ti, Nb, Ta, P. Rock samples have high Rb/Sr (average for 6.22) and Rb/ Nb ratio (average for 1.447), and rich uranium (average for 9.04 x 10 -6 ) which can act as the source for the formation of uranium deposit. In REE chemistry, the pluton is rich in LREE and relatively high fractionation between LREE and HREE, and bear the right-wing-type distribution pattern with obviously Eu depletion. In Isotopic chemistry,the pluton has low ε Nd (t) value(average for -10.6), high ( 87 Sr/ 86 Sr) i value (average for 0.71688), and old Nd mode age (1865∼1874 Ma). These characteristics consistently show that Baiyun pluton belongs to typical crustal source granite type and formed in an extensional tectonic environment shortly after the collision between South China and Indo-China plate from partial melting of argillaceous rocks in the middle-lower crust due to the comprehensive action of the decompression, water-prodution and mantle upwelling induced by crust stretching and thinning. (authors)

Magmatic tempo of Earth's youngest exposed plutons as revealed by detrital zircon U-Pb geochronology.

Science.gov (United States)

Ito, Hisatoshi; Spencer, Christopher J; Danišík, Martin; Hoiland, Carl W

2017-09-29

Plutons are formed by protracted crystallization of magma bodies several kilometers deep within the crust. The temporal frequency (i.e. episodicity or 'tempo') of pluton formation is often poorly constrained as timescales of pluton formation are largely variable and may be difficult to resolve by traditional dating methods. The Hida Mountain Range of central Japan hosts the youngest exposed plutons on Earth and provides a unique opportunity to assess the temporal and spatial characteristics of pluton emplacement at high temporal resolution. Here we apply U-Pb geochronology to zircon from the Quaternary Kurobegawa Granite and Takidani Granodiorite in the Hida Mountain Range, and from modern river sediments whose fluvial catchments include these plutons in order to reconstruct their formation. The U-Pb data demonstrate that the Kurobegawa pluton experienced two magmatic pulses at ~2.3 Ma and ~0.9 Ma; whereas, to the south, the Takidani pluton experienced only one magmatic pulse at ~1.6 Ma. These data imply that each of these magmatic systems were both spatially and temporally distinct. The apparent ~0.7 Myr age gap between each of the three magmatic pulses potentially constrains the recharge duration of a single pluton within a larger arc plutonic complex.

Geochemical and chronological characteristics of Xiangcaoping granite pluton in Miaoershan area

International Nuclear Information System (INIS)

Li Wuwei; Wang Gan; Chen Weifeng; Zhao Kuidong

2010-01-01

Xiangcaoping granite pluton is mainly composed of medium-macro grain porphyritic biotite. The age of signle zircon dated by SHRIMP U-Pb is 211 ± 2 Ma, which suggest s that this pluton was formed during Indosinan. The geochemical characteristics is A > CNK, trace elements spider chart is slightly oblique to the right, enriched in LREE and bears obvious negative Eu anomaly which is similar to that of the S-type granite in South China. High ("8"7Sr/"8"6Sr)_i and low ε_N_d (t) suggest that this pluton was derived from partial melting of middle maturity Precambrian basement rock, which was rich in uranium and had supplied enough U element to the formation of Xiangcaoping granite pluton. (authors)

Magmatic apatite - a window into melt evolution of the Dalgety pluton.

Science.gov (United States)

Pope, M. D.; Tailby, N.; Webster, J. D.

2017-12-01

The Dalgety Pluton is located in the Lachlan Fold Belt in southeastern Australia, and is a coarse grained, peraluminous, S-type, biotite granodiorite. Historically, pluton emplacement has been thought of as cooling from a single, large body of magma over a geologically quick period. Current studies suggest issues with this model and propose a slower, incremental model of emplacement in some settings (Glazner et al., 2004). This work proposes that the emplacement of the Dalgety Pluton occurred in incremental phases demonstrated through halogen, minor, and trace element concentrations in apatites. Apatites from 13 samples collected along a north-south transect of the pluton were analyzed using a 5-spectrometer Cameca SX-100 calibrated for seventeen elements (F, Na, Cl, P, Mg, Al, Si, Ca, S, K, Ti, Mn, Fe, Sr, Ba, La, and Ce) at the American Museum of Natural History. The majority of apatites are fluorapatites, having >50 % F, <15 % Cl, and <25 % OH (calculated from Ketchum et al., 2015). However, the concentrations of the halogens vary throughout the pluton with the highest Cl concentrations near the southern edge. Two of the minor elements, Mn and Fe, also show distinct variation with the lowest concentrations being 0.35 wt% in Mn and 0.25 wt% in Fe and the highest being 1.10 wt% and 0.95 wt%, respectively. Trace elements Ce and La vary as well with their highest concentrations being 0.29 wt% and 0.11 wt% and their lowest for both being below the detection limit of the electron probe. Elemental variation across the pluton is seen in the concentration of minor elements and halogens with a sharp increases at 10,000 meters and again at 21,000 meters from the southern rim of the pluton. Similar shifts in concentration are also seen in the trace elements, however the concentrations decrease at these distances. These wholesale elemental fluctuations in composition are indicative of a dramatic shift in melt composition supporting the hypothesis of multiple melt injection

Magma flow recorded by magmatic and magnetic fabrics in a shallow granitic pluton: La Gloria Pluton, central Chile

Science.gov (United States)

Payacán, I. J.; Gutiérrez, F. J.; Gelman, S. E.; Bachmann, O.; Parada, M. A.

2013-12-01

To better understand the dynamics of a small, shallow, silicic magma reservoir, magmatic and magnetic (AMS) fabrics are compared in samples obtained from La Gloria Pluton (LGP), a 10 Ma granitic intrusion located in southern Andes. The magnetic fabric of LGP, mainly given by magnetite, is characterized by oblate shapes. Magnetic lineations have a NW trend with subhorizontal dip, following the main pluton elongation, while magnetic foliation planes have dips varying gradually from vertical at the walls to subhorizontal toward the center and the roof of the pluton. On the basis of numerical simulations, magnetic fabric was interpreted to represent the shear record induced by magmatic convection along solidification fronts as the reservoir reached its rheological locking point. Magmatic fabric (mineral orientation) was determined on 12 samples along the pluton. Three mutually orthogonal thin sections were produced for each sample, perpendicular to the AMS tensor axes. Size and orientation of individual crystals were obtained by image analysis. A 2-D tensor for two mineral groups (plagioclase and amphibole+biotitie) was defined in each mineral plane projecting the crystal lengths on the main crystal orientation (given by Bingham statistics). A 3-D magmatic fabric tensor was obtained. In order to compare the magmatic and magnetic fabrics, magmatic anisotropy parameters were defined similar to the AMS tensors. Magmatic fabric and anisotropy parameter values vary depending on the location inside the pluton: (1) Samples located at the borders exhibit vertical foliations and lineations with a NW trend, similar to the magnetic fabric tensors and higher anisotropy values for plagioclase than amphibole+biotite,; (2) samples located at the center of the LGP commonly present subvertical foliations/lineations, which differ from the magnetic fabric, and higher magmatic anisotropy degree values for amphibole+biotite than plagioclase. Based on numerical simulations of the fluid

Predictibilidad de los retornos en el mercado de Colombia e hipótesis de mercado adaptativo

Directory of Open Access Journals (Sweden)

Katherine Julieth Sierra Suárez

2015-10-01

Full Text Available Los mercados eficientes son aquellos en los cuales no es posible predecir los retornos de sus activos. No obstante, la hipótesis de mercado adaptativo afirma que la eficiencia no es una característica estática de los mercados, sino que varía en el tiempo de acuerdo a las condiciones del mercado y al comportamiento de sus agentes. Este trabajo busca evaluar la predictibilidad del mercado colombiano, usando el test Ratio de varianza automático en ventanas móviles de tiempo para comprobar si es eficiente, y si la eficiencia es una característica estática o dinámica de este mercado. Los resultados muestran que los índices accionarios de Colombia presentan periodos de predictibilidad y periodos de alta incertidumbre que son consistentes con un mercado adaptativo.

Sedimentary rocks Uranium in Cerro Largo Province; Uranio en rocas sedimentarias en el departamento de Cerro Largo

Energy Technology Data Exchange (ETDEWEB)

Scaron, P; Garau Tous, M

1976-07-01

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.

Granitoids of the Dry Valleys area, southern Victoria Land, Antarctica : plutons, field relationships, and isotopic dating

International Nuclear Information System (INIS)

Allibone, A.H.; Cox, S.C.; Johnstone, R.D.

1993-01-01

Detailed mapping throughout much of the Dry Valleys area indicates the region is underlain by 15 major granitoid plutons and numerous smaller plugs and dikes. Intrusive relationships of these plutons and dikes indicate repeated intrusion of superficially similar granitoids at different times. Sufficient internal lithologic variation occurs within individual plutons, to allow correlation with several of the previously defined granitoid units based on lithologic character. Consequently, previous subdivision schemes based on lithology are no longer tenable and are here replaced with a subdivision scheme based on the identification of individual plutons. The elongate, concordant Bonney, Denton, Cavendish, and Wheeler Plutons, which range in composition between monzodiorite and granodiorite, are the oldest relatively undeformed plutons in the Dry Valleys area. Each pluton is characterised by flow alignment of K-feldspar megacrysts, hornblende, biotite, and mafic enclaves. Field relationships and radiometric dating indicate these are deep-level plutons, emplaced synchronous with upper amphibolite facies metamorphism of the adjacent Koettlitz Group between 589 and 490 Ma ago. Elongate, discordant plutons of equigranular homogeneous biotite granodiorite and granite (Hedley, Valhalla, St Johns, Suess) were subsequently emplaced by stoping at a relatively high crustal level at 490 Ma. These eight plutons are cut by numerous swarms of Vanda mafic and felsic porphyry dikes. The ovoid, discordant, high level Pearse, Nibelungen, Orestes, Brownworth, Swinford, and Harker Plutons, emplaced between c. 486 and 477 Ma, display mutually crosscutting relationships with the youngest of the Vanda dikes. These younger plutons range in composition between monzonite and granite. Some are characterised by K-feldspar megacrystic textures superficially similar to some of the oldest concordant plutons. (author). 57 refs.; 2 tabs.; 4 figs

A PCR detection method for rapid identification of Melissococcus pluton in honeybee larvae.

Science.gov (United States)

Govan, V A; Brözel, V; Allsopp, M H; Davison, S

1998-05-01

Melissococcus pluton is the causative agent of European foulbrood, a disease of honeybee larvae. This bacterium is particularly difficult to isolate because of its stringent growth requirements and competition from other bacteria. PCR was used selectively to amplify specific rRNA gene sequences of M. pluton from pure culture, from crude cell lysates, and directly from infected bee larvae. The PCR primers were designed from M. pluton 16S rRNA sequence data. The PCR products were visualized by agarose gel electrophoresis and confirmed as originating from M. pluton by sequencing in both directions. Detection was highly specific, and the probes did not hybridize with DNA from other bacterial species tested. This method enabled the rapid and specific detection and identification of M. pluton from pure cultures and infected bee larvae.

Iron variation within a granitic pluton as determined by near-infrared reflectance

Science.gov (United States)

Baird, A. K.

1984-01-01

One-hundred fifty-one previously chemically analyzed samples of tonalite from the Lakeview Mountains pluton, southern California batholith, were analyzed for their iron content using near-infrared spectrophotometry. Compared to the earlier analyses of the same sample set by X-ray fluorescence spectrography, the infrared data have higher analytical variance but clearly define patterns of compositional zonation in the pluton which are closely similar to those patterns obtained from X-ray data; petrogenetic interpretations for the pluton would be the same from either data set. Infrared spectral data can be obtained directly in the field with relatively simple instruments and field measurements can be made to average local heterogeneities that often mask significant plutonic variations.

Research on the age and origin of Hongshan pluton in north Guangdong

International Nuclear Information System (INIS)

Zhu Ba; Deng Peng; Ling Hongfei; Shen Weizhou; Tan Zhengzhong

2009-01-01

Located in the midwest of south Zhuguangshan composite pluton, Hongshan pluton is constituted by biotite granite and two-micro granite. The SHRIMP U-Pb age of zircons from the pluton is 155±2 Ma, which belongs to Yanshanian. Hongshan pluton is rich in silicon (SiO 2 =76.08%∼77.25%) and alkali(K 2 O+Na 2 O=8.78%∼9.43%), low in ACNK value (0.94∼1.07) and CaO/Na 2 O value (0.10∼0.19). In trace elements, the pluton is rich in Rb, Th, U, depleted in Ba, Sr, P, Ti and has high Rb/Sr (30.02∼930.9), Rb/Ba (18.91∼231.8), has low LREE/HREE value (1.99∼2.40) and remarkable Eu depletion (δEu=0.01∼0.07), has low Σ Nd (t) value (-10.2∼-12.0) and old Nd model age(1777∼1923 Ma). All the evidence indicate that it have the characteristic of S type granite. Hongshan pluton is believed to be formed by partial melting of protozoic rocks, which related to the reactivation of Qitianling-Zhuguangshan (east-west) fracture zones resulted from the subduction of Pacific plate. (authors)

Geochemistry and U/Pb geochronology of the Neuvy-Bouin pluton (Vendean Haut-Bocage): an example of a multistage granite pluton

International Nuclear Information System (INIS)

Cuney, M.; Brouand, M.; Dautel, D.; Michard, A.; Stussi, J.M.; Poncet, D.; Bouton, P.; Colchen, M.; Vervialle, J.P.

1993-01-01

New geological, structural and geochemical data show the presence of at least four magmatic units in the Neuvy-Bouin massif. U/Pb zircon age (340±4 Ma) obtained on the Largeasse granites indicates that in the Neuvy-Bouin pluton the magmatic activity began during Visean times. The emplacement of the Largeasse granites is followed by the aluminopotassic two-mica granites of Pougne-Herisson and by two mica leucogranites. The small high-K calc-alkaline granite body discovered in the Neuvy-Bouin pluton represents the first occurrence of this type of magmatism in the area

An Archean Geomagnetic Reversal in the Kaap Valley Pluton, South Africa

Science.gov (United States)

Layer; Kroner; McWilliams

1996-08-16

The Kaap Valley pluton in South Africa is a tonalite intrusion associated with the Archean Barberton Greenstone Belt. Antipodal paleomagnetic directions determined from the central and marginal parts of the pluton record a geomagnetic reversal that occurred as the pluton cooled. The age of the reversal is constrained by an 40Ar/39Ar plateau age from hornblende at 3214 +/- 4 million years, making it the oldest known reversal. The data presented here suggest that Earth has had a reversing, perhaps dipolar, magnetic field since at least 3.2 billion years ago.

High-18O granitic plutons from the Frontenac Axis, Grenville Province of Ontario, Canada

International Nuclear Information System (INIS)

Shieh, Y.-N.

1985-01-01

18 O/ 16 O ratios have been determined for whole rock as well as coexisting minerals from nine syn- to post-tectonic monzonite and quartz monzonite plutons in the Westport-Gananoque area covering approximately 2500 km 2 . The plutons fall into two distinct isotopic groups: (I) Low- 18 O group: Rideau Lake, Westport, and Wolfe Lake plutons and (II) High- 18 O group: Lyndhurst, Perth Road, Battersea, Gananoque, South Lake and Crow Lake plutons. The 18 O/ 16 O ratios of granitic rocks from the latter group are among the highest ever reported in the literature. The isotopic compositions of samples within each pluton bear no relationship to the sample distance from the intrusive contacts nor are they affected by the types of country rocks into which they are emplaced. Oxygen isotope fractionations among coexisting quartz, feldspar, biotite and magnetite all show normal plutonic values. Thus, all lines of evidence suggest that the monzonite and quartz monzonite plutons did not acquire their characteristic 18 O/ 16 O ratios at the present level of exposure, either by isotopic exchange with the surrounding metasedimentary country rocks or by any post-crystallization low-temperature alteration processes. The results are discussed. (author)

Discussion on geochemical characteristics and tectonic setting of Maofeng pluton

International Nuclear Information System (INIS)

Wu Yi; Ruan Kun; Cai Jiajia; Liu Jing; Li Haidong; Zhang Lu; Wang Xiaona

2014-01-01

Xiazhuang granite type uranium deposit is the most important one in South China. The closest relation with Xiazhuang uranium mineralization is Maofeng granite pluton. To expound the relationship of granite and uranium mineralization, the paper studied Maofeng granite pluton which is the host granite of the deposit in petrogeochemistry, its structure and geodynamic setting. (authors)

Bullialdus - Strengthening the case for lunar plutons

Science.gov (United States)

Pieters, Carle M.

1991-01-01

Although many craters expose materials of a composition different from that of the local surroundings, Bullialdus has excavated material representing three distinct stratigraphic zones that occur in the upper 6 km of crust, the top two of which are gabbroic and the deepest of which is noritic. This three-component stratigraphy at Bullialdus provides strong evidence that the lunar crust includes pockets of compositionally layered material reminiscent of mafic layered plutons. When combined with previous information on the compositional diversity at other large craters, these remote analyses obtained in a geologic context substantially strengthen the hypothesis suggested from lunar samples that plutons play an integral role in lunar crustal evolution.

Lateral extrusion of a thermally weakened pluton overburden (Campiglia Marittima, Tuscany)

Science.gov (United States)

Vezzoni, Simone; Rocchi, Sergio; Dini, Andrea

2017-10-01

The ascent and emplacement of magmas in the upper crust modify the local pre-existing thermal and rheological settings. Such changes have important effects in producing anomalous structures, mass extrusion, rock fracturing, and in some conditions, hydrothermal mineralizations. In the Campiglia Marittima area, detailed field mapping led to the reconstruction of a local deformation history that overlaps, chronologically and spatially, with regional extension. This local deformation was triggered at the Miocene-Pliocene boundary by the intrusion of a monzogranitic pluton beneath a carbonate sedimentary sequence. The emplacement of the pluton produced a perturbation in the rheological behaviour of the carbonate host rocks, producing transient ductile conditions in the very shallow crust. The carbonate rocks were thermally weakened and flowed laterally, accumulating downslope of the pluton roof, mainly toward the east. As the thermal anomaly was decaying, the brittle-ductile boundary moved progressively back towards the pluton, and large tension gash-shaped volumes of fractured marble were generated. These fractured volumes were exploited by rising hydrothermal fluids generating sigmoidal skarn bodies and ore shoots. This work presents the Campiglia Marittima case study as a prime example of structural interference between regional extensional structures and local, lateral mass extrusion in a transient ductile rheological regime triggered by pluton emplacement.

Isotopic character of Cambro-Ordovician plutonism, southern Victoria Land

International Nuclear Information System (INIS)

Cox, S.C.; Parkinson, D.L.; Allibone, A.H.; Cooper, A.F.

2000-01-01

Previous mapping of granitoid rocks in the Dry Valleys area of southern Victoria Land, Antarctica, identified the calc-alkaline (DV1a), adakitic (DV1b), and monzonitic (DV2) suites. A fourth older suite comprising alkaline gabbro, syenite, and A-type granite occurs in the Mt Dromedary area c. 80 km to the south. U-Pb zircon dating of Bonney Pluton, the largest calc-alkaline DV1a intrusion, indicates emplacement of this regional-scale body at 505 +/- 2 Ma. Pb-loss and inherited zircon were common to Bonney Pluton analyses of this study. U-Pb dating of monazite from Valhalla Pluton, a principal DV1b suite adakitic intrusion, indicates emplacement at 488 +/- 2 Ma. The Bonney Pluton age constrains the peak of calc-alkaline plutonism at 505 Ma and the Valhalla Pluton age records the major pulse of adakitic plutonism that is inferred to mark the final stages of subduction c. 490 Ma along this section of the East Antarctic margin. Nd and Sr isotope data for the calc-alkaline DV1a suite and adakitic DV1b suite define distinct ranges for each suite, supporting their subdivision on the basis of field relationships, petrography, and whole-rock geochemistry. Calc-alkaline DV1a suite granite magmas have eNd(T) = -4.2 to -6.1 and Sri = 0.7071-0.7079, whereas the adakitic DV1b suite rocks have a wider range of eNd(T) = -1.9 to -7.2 and Sri = 0.7065-0.7097. The isotopic data suggest a significant mantle component and subordinate crustal component in the source region of both suites. Time-dependent variations in the isotopic ratios of DV1a and DV1b suites imply a progressive increase in the proportion of more radiogenic material in the source region of the granitoid rocks, either mantle- or crust-derived material. Larger adakitic DV1b plutons are more 'evolved' than equivalent, smaller plutons of the same DV1b suite. Vanda Dikes and monzonitic DV2 suite intrusions are characterised by particularly low Sri = 0.7044-0.7067 and near-constant eNd(T) = -4.8 to -5.3, which indicate a

Magnetic properties of ilmenite-hematite single crystals from the Ecstall pluton near Prince Rupert, British Columbia

DEFF Research Database (Denmark)

Brownlee, Sarah J.; Feinberg, Joshua M.; Kasama, Takeshi

2011-01-01

Paleomagnetic studies of the 91 Ma Ecstall pluton and other Cretaceous plutons of British Columbia imply large northward tectonic movements (>2000 km) may have occurred during the tectonic evolution of western North America. However, more recent studies have shown that the eastern edge...... of the Ecstall pluton experienced considerable mineralogical changes as younger Eocene plutons, such as the ∼58 Ma Quottoon Pluton, were emplaced along its margins. We investigated changes in the rock magnetic properties associated with this reheating event by examining isolated grains of intergrown ilmenite...... and hematite, the primary paleomagnetic recorder in the Ecstall pluton. Measurements of hysteresis properties, low-temperature remanence, and room temperature isothermal remanent magnetization acquisition and observations from magnetic force microscopy and off-axis electron holography indicate that samples...

Reconnaissance study of the uranium and thorium contents of plutonic rocks of the southwestern Seward Peninsula, Alaska

International Nuclear Information System (INIS)

Miller, T.P.; Bunker, C.M.

1976-01-01

Large granitic Cretaceous plutons are exposed along and adjacent to an arcuate belt of igneous and high-grade metamorphic rocks in the southeastern Seward Peninsula of Alaska. Reconnaissance studies of these plutons have shown that the Darby pluton has well above average amounts of uranium and thorium (11.2 ppm and 58.7 ppm, respectively), the Kachauik pluton contains average to above average uranium and thorium (5.7 ppm and 22.5 ppm, respectively), and the Bendeleben pluton contains average amounts of uranium and thorium (3.4 ppm and 16.7 ppm, respectively). The three plutons show compositional and textural differences indicative of different source materials that may have controlled the distribution of uranium and thorium. The high uranium and thorium contents of the Darby pluton, similar to those of the Conway Granite of New Hampshire which has been mentioned as a possible low-grade thorium resource, suggest that this pluton may be a favorable area for economic concentrations of uranium and thorium

MECANISMOS UTILIZADOS PARA MONITOREAR EL PODER DE MERCADO EN MERCADOS ELÉCTRICOS: REFLEXIONES PARA COLOMBIA

Directory of Open Access Journals (Sweden)

Jesús Alonso Botero

2013-12-01

Full Text Available El propósito de este trabajo es analizar la viabilidad de la utilización del índice de oferta residual (IOR en el mercado eléctrico mayorista en Colombia, con el fin de promover la competencia. Esto se hace a partir de la revisión de la literatura relacionada con las experiencias internacionales respecto a los mecanismos para monitorear el poder de mercado y del análisis del Documento 118 de la Comisión de Regulación de Energía y Gas (CREG, 2010. La principal conclusión es que el IOR no es un buen mecanismo de control en mercados hidráulicos, mientras que el desarrollo de los mercados de largo plazo ha sido utilizado con gran éxito para mitigar el riesgo de abuso de poder de mercado, seg°n lo muestra la experiencia internacional.

Sedimentary rocks Uranium in Cerro Largo Province

International Nuclear Information System (INIS)

Scaron, P.; Garau Tous, M.

1976-01-01

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

Cretaceous plutonic rocks in the Donner Lake-Cisco Grove area, northern Sierra Nevada, California

Science.gov (United States)

Kulow, Matthew J.; Hanson, Richard E.; Girty, Gary H.; Girty, Melissa S.; Harwood, David S.

1998-01-01

The northernmost occurrences of extensive, glaciated exposures of the Sierra Nevada batholith occur in the Donner Lake-Cisco Grove area of the northern Sierra Nevada. The plutonic rocks in this area, which are termed here the Castle Valley plutonic assemblage, crop out over an area of 225 km2 and for the most part are shown as a single undifferentiated mass on previously published geological maps. In the present work, the plutonic assemblage is divided into eight separate intrusive units or lithodemes, two of which each consist of two separate plutons. Compositions are dominantly granodiorite and tonalite, but diorite and granite form small plutons in places. Spectacular examples of comb layering and orbicular texture occur in the diorites. U-Pb zircon ages have been obtained for all but one of the main units and range from ~120 to 114 Ma, indicating that the entire assemblage was emplaced in a narrow time frame in the Early Cretaceous. This is consistent with abundant field evidence that many of the individual phases were intruded penecontemporaneously. The timing of emplacement correlates with onset of major Cretaceous plutonism in the main part of the Sierra Nevada batholith farther south. The emplacement ages also are similar to isotopic ages for gold-quartz mineralization in the Sierran foothills west of the study area, suggesting a direct genetic relationship between the voluminous Early Cretaceous plutonism and hydrothermal gold mineralization.

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)

Solis, R.J.; Navarra, P.R.; Benitez, A.F.; Gallucci, A.R.

1993-01-01

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)

El mercado balcón o segundo mercado como alternativa de participación de las PYMES en el mercado de capitales de Colombia

Directory of Open Access Journals (Sweden)

Moisés Quevedo Céspedes

2015-02-01

Teniendo como base el informe final del trabajo, presentado por estudiantes de último nivel del programa de Administración de Empresas y de la Especializaciación en Administración Financiera. el cual tuve la oportunidad de dirigir durante dos periodos académicos, presento a consideración de la academia el resultado del estudio sobre el mercado balcón o segundo mercado como alrternativa de participación de las PYMES en el mercado de capitales de Colombia.

Plutonic rocks of the Median Batholith in southwest Fiordland, New Zealand : field relations, geochemistry, and correlation

International Nuclear Information System (INIS)

Allibone, A.H.; Turnbull, I.M.; Tulloch, A.J.; Cooper, A.F.

2007-01-01

This paper provides a first description of all major plutonic rock units between Resolution Island and Lake Poteriteri in southwest Fiordland. Plutonic rocks, of which c. 95% are granitoids, comprise c. 60% of the basement in southwest Fiordland. Approximately 50% of the plutonic rocks were emplaced between c. 355 and 348 Ma, 5% at c. 164 Ma, 25% between c. 140 and 125 Ma, and 20% between c. 125 and 110 Ma. These episodes of plutonism occurred in response to terrane amalgamation, continental thickening, and subduction along the convergent margin of Gondwana. Correlatives of Devonian plutonic rocks which occur in Nelson are absent from the area described here. A wide variety of plutonic rocks were emplaced at c. 355-348 Ma. These include relatively small plutons of K- and Rb-rich gabbro-diorite and members of at least three distinct suites of granitoids. Plutons of two-mica ± garnet granodiorite, granite, and minor tonalite share affinities with the S-type Ridge Suite and are the most widespread c. 355-348 Ma old granitoids in southern Fiordland. Plutons rich in Ca, Fe and Zr, depleted in K and Na, and containing quartz diorite, tonalite, and minor granodiorite with the unusual assemblage red-brown biotite, garnet ± hornblende ± clinopyroxene also occur widely in southern Fiordland. These plutons are similar to peraluminous A-type granitoids, indicating A as well as I and S-type plutonism occurred in the Western Province at this time. The Newton River and Mt Evans Plutons have no correlatives amongst c. 355-348 Ma granitoids in southern Fiordland, but their chemistry is similar to that of the older Karamea Suite. Three regional-scale metasedimentary units - locally fossiliferous Fanny Bay Group Buller Terrane rocks in southern Fiordland, Edgecumbe and Cameron Group Takaka Terrane rocks in south-central Fiordland, and undifferentiated Deep Cove Gneiss high-grade metasedimentary rocks of western Fiordland - are all stitched by c. 355-348 Ma old plutons, indicating

Natural radioactivity levels in granitic plutons and groundwaters in Southeast part of Eskisehir, Turkey

Energy Technology Data Exchange (ETDEWEB)

Oerguen, Y. [Faculty of Mines, Istanbul Technical University (ITU), Ayazaga Kampusu, 34469 Istanbul (Turkey)]. E-mail: orgun@itu.edu.tr; Altinsoy, N. [Institute of Energy, Istanbul Technical University (ITU), Ayazaga Kampusu, 34469 Istanbul (Turkey); Gueltekin, A.H. [Faculty of Mines, Istanbul Technical University (ITU), Ayazaga Kampusu, 34469 Istanbul (Turkey); Karahan, G. [Cekmece Nuclear Research and Training Center, P.O. Box 1, Atatuerk Airport, 34149 Istanbul (Turkey); Celebi, N. [Cekmece Nuclear Research and Training Center, P.O. Box 1, Atatuerk Airport, 34149 Istanbul (Turkey)

2005-08-01

The present work investigated the radioactivity level of the granitoid plutons and its effect on the groundwaters in the southeast part of Eskisehir. Fourteen granitic samples from the Kaymaz and Sivrihisar plutons and 11 groundwater samples from the near vicinity of the pluton were analyzed. The activity concentrations measured for {sup 238}U and {sup 232}Th ranged from 43.59{+-}2 to 651.80{+-}24 Bq/kg, and 51.16{+-}3 to 351.94{+-}13 Bq/kg, respectively. The activity concentrations obtained for {sup 40}K varied from 418.50{+-}17 to 1618.03{+-}66 Bq/kg. The absorbed dose rates in air outdoors ranged from 87.14 to 531.81 nGy/h. All the results obtained from the Kaymaz pluton are higher than those from the Sivrihisar. The U (ave. 16.6 ppm) and Th (ave. 49.9 ppm) values of the Kaymaz pluton are higher than the average concentrations of the magmatic rocks of granitic composition. These results are consistent with high dose rates of the pluton. The gross-{alpha} activities in the groundwater samples ranged from 0.009 to 1.64 Bq/l and the gross-{beta} activities from 0.006 to 0.89 Bq/l. The highest gross-{alpha} value was found in the sample taken from near the Kaymaz pluton. The concentrations of {sup 222}Rn varied from 0.060 to 0.557 Bq/l.

El mercado balcón o segundo mercado como alternativa de participación de las PYMES en el mercado de capitales de Colombia

OpenAIRE

Moisés Quevedo Céspedes

2015-01-01

RESUMEN Teniendo como base el informe final del trabajo, presentado por estudiantes de último nivel del programa de Administración de Empresas y de la Especializaciación en Administración Financiera. el cual tuve la oportunidad de dirigir durante dos periodos académicos, presento a consideración de la academia el resultado del estudio sobre el mercado balcón o segundo mercado como alrternativa de participación de las PYMES en el mercado de capitales de Colombia.

Mercado de Algeciras

Directory of Open Access Journals (Sweden)

Torroja, Eduardo

1962-02-01

Full Text Available Siguiendo las líneas generales del Anteproyecto aprobado por el Excmo. Ayuntamiento de Algeciras, se proyectó el nuevo Mercado con una planta octogonal inscrita en el polígono que forman las cuatro calles de contorno. De este modo se obtiene una sala de gran utilización para los puestos de venta, sin rincones difíciles de acceso; y la entrada desde los cuatro lados se obtiene fácilmente, descongestionando así la circulación en los alrededores del Mercado. Esta circulación se facilita, también, con los chaflanes que en las esquinas de las calles presentan cuatro lados del octógono, y que, sin perjudicar a los servicios interiores, permite dar mayor amplitud a las aceras, punto importante dadas las aglomeraciones que suelen producirse en los alrededores de estos mercados en las horas de compra.

Fractures and fracture infillings of the Eye-Dashwa Lakes pluton, Atikokan, Ontario

International Nuclear Information System (INIS)

Stone, Denver; Kamineni, D.C.

1982-01-01

Fractures in the Eye-Dashwa pluton near Atikokan, Ontario can be subdivided on the basis of their filling materials. These materials include aplite, epidote, chlorite, and gypsum-carbonate-clay, listed in order of decreasing age established from crosscutting relations. Textues indicate that infilling occurred during fracture growth. Continuous cooling of the pluton during fracturing is inferred from the expected crystallization temperatures of fillings. Fracturing began before the pluton was completely solidified (650-600 0 C) and continued to temperatures below 100 0 C. Many fractures appear to have been sealed by the filling materials after initiation but were subsequently sheared and filled by lower temperatue materials. Apparently the majority of fractures formed during or immediately after pluton solidification and new fractures became smaller and more restricted in location as cooling progressed. Fractures and filling materials are seen as important features in assessing the possibility of movement of radionuclides in aqueous solutions away from a nuclear fuel waste repository

Reconnaissance study of the Taylor Mountains pluton, southwestern Alaska

Science.gov (United States)

Hudson, Travis L.; Miller, Marti L.; Klimasauskas, Edward P.; Layer, Paul W.

2010-01-01

The Taylor Mountains pluton is a Late Cretaceous to early Tertiary (median age 65 + or ? 2 Ma) epizonal, composite biotite granite stock located about 235 km (145 mi) northeast of Dillingham in southwestern Alaska. This 30 km2 (12 mi2) pluton has sharp and discordant contacts with hornfels that developed in Upper Cretaceous clastic sedimentary rocks of the Kuskokwim Group. The three intrusive phases in the Taylor Mountains pluton, in order of emplacement, are (1) porphyritic granite containing large K-feldspar phenocrysts in a coarse-grained groundmass, (2) porphyritic granite containing large K-feldspar and smaller, but still coarse, plagioclase, quartz, and biotite phenocrysts in a fine-grained groundmass, and (3) fine-grained, leucocratic, equigranular granite. The porphyritic granites have different emplacement histories, but similar compositions; averages are 69.43 percent SiO2, 1.62 percent CaO, 5.23 percent FeO+MgO, 3.11 percent Na2O, and 4.50 percent K2O. The fine-grained, equigranular granite is distinctly felsic compared to porphyritic granite; it averages 75.3 percent SiO2, 0.49 percent CaO, 1.52 percent FeO+MgO, 3.31 percent Na2O, and 4.87 percent K2O. Many trace elements including Ni, Cr, Sc, V, Ba, Sr, Zr, Y, Nb, La, Ce, Th, and Nd are strongly depleted in fine-grained equigranular granite. Trace elements are not highly enriched in any of the granites. Known hydrothermal alteration is limited to one tourmaline-quartz replacement zone in porphyritic granite. Mineral deposits in the Taylor Mountains area are primarily placer gold (plus wolframite, cassiterite, and cinnabar); sources for these likely include scattered veins in hornfels peripheral to the Taylor Mountain pluton. The granite magmas that formed the Taylor Mountains pluton are thought to represent melted continental crust that possibly formed in response to high heat flow in the waning stage of Late Cretaceous subduction beneath interior Alaska.

ControlFluid: un mercado variable

OpenAIRE

Villa Duran, Nicolas

2014-01-01

Las estrategias de una empresa en un mercado pequeño donde hay pocos compradores y muchos vendedores se vuelven el centro y punto clave de éxito, de lo contrario la empresa solo sigue una tendencia de mercado que al mediano plazo no resultara efectiva y terminan desapareciendo. Es por ello que las estrategias de mercado en las empresas se vuelven la característica diferenciadora permitiendo tomar ventaja del hacinamiento de un sector. Para que una empresa sea exitosa debe tener en cuenta sus ...

The research on the geochemical characteristics of Longyuanba composite pluton in Nanling region

International Nuclear Information System (INIS)

Zhang Min; Chen Peirong; Ling Hongfei

2006-01-01

The Longyuanba composite pluton, located in the eastern part of the Nanling Range, is an important part of the Nanling granites belt, which was regarded as a portion of Yanshanian epoch Pitou pluton to the east of it, and was lowly studied. The newest research shows that, the main body of Longyuanba pluton formed in Indosinian, different from Pitou pluton, which is Yanshanian. From main elements geochemical characteristics, there is obvious gap between Indosinian granites, Yanshanian granites and Yanshanian syenites in major oxides composition, which implies that there is possibly no fractional crystallization relationship between them. Form trace element geochemical characteristics, Indosinian Σ granites are enriched in LREE and high in REE. Yanshanian granites are depleted in MREE and low in Σ REE and ratios of Th/U, Nb/Ta, Zr/Hf, and obvious in fraction. The above characteristics show that, liquid action was rather strong in Yanshanian magmatism. Yanshanian syenites are enriched in high field elements and REE, are similar with A-type granite. Sr, Nd isotopic geochemical characteristics show that, Longyuanba composite pluton belongs to crust-original S-type granite and its original resource is early-Proterozoic crust from crust-mantle fraction. (authors)

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.

Unusual Rb-Sr data on the age of two typical peralkaline granitoid plutons in West Transbeikalia

International Nuclear Information System (INIS)

Litvinovskij, B.A.; Posokhov, V.F.; Zanvilevich, A.N.

1995-01-01

Rb-Sr isotope study of two typical plutons in West Transbaikalia (Bryansk and Kharitonov) has been carried out. For alkaline and peralkaline suits of the Bryansk pluton the obtained data are 287 ± m.y., I Sx =0.7054 ± 3 and 285 ± 1 m.y., I Sr =0.7037 ± 3 respectively. Rb-Sr age of peralkaline syenites and granites from the Kharitonov pluton are in more or less consistency with those on the Malokunal pluton (233 ± 5 m.y.) and much less than the age of the Khorinsk pluton (253 ± 3 m.y.). Taking into account the K-Ar data on amphibole from the peralkaline granitoids it is concluded that probable age of these rocks span the interval 250-220 m.y. However results obtained from the Bryansk pluton suggest that within the Mongolia-Transbaikalia belt one more stage of peralkaline granitoid generation i.e. the Early Permian stage could be manifested as well. 20 refs.; 5 figs.; 3 tabs

Exploration and development of Cerro Prieto

Energy Technology Data Exchange (ETDEWEB)

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

1981-01-01

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

Is there a geochemical link between volcanic and plutonic rocks in the Organ Mountains caldera?

Science.gov (United States)

Memeti, V.; Davidson, J.

2013-12-01

Results from separate volcanic and plutonic studies have led to inconsistent conclusions regarding the origins and thus links between volcanic and plutonic systems in continental arcs and the magmatic processes and time scales responsible for their compositional variations. Some have suggested that there is a geochemical and geochronological disconnect between volcanic and plutonic rocks and hence have questioned the existence of magma mush columns beneath active volcanoes. Investigating contemporary volcanic and plutonic rocks that are spatially connected is thus critical in exploring these issues. The ca. 36 Ma Organ Mountains caldera in New Mexico, USA, represents such a system exposing contemporaneous volcanic and plutonic rocks juxtaposed at the surface due to tilting during extensional tectonics along the Rio Grande Rift. Detailed geologic and structural mapping [1] and 40Ar/39Ar ages of both volcanics and plutons [2] demonstrate the spatial and temporal connection of both rock types with active magmatism over >2.5 myr. Three caldera-forming ignimbrites erupted within 600 kyr [2] from this system with a total erupted volume of 500-1,000 km3 as well as less voluminous pre- and post-caldera trachyte and andesite lavas. The ignimbrite sequence ranges from a crystal-poor, high-SiO2 rhyolite at the base to a more crystal-rich, low-SiO2 rhyolite at the top. Compositional zoning with quartz-monzonite at the base grading to syenite and alaskite at the top is also found in the Organ Needle pluton, the main intrusion, which is interpreted to be the source for the ignimbrites [1]. Other contemporaneous and slightly younger plutons have dioritic to leucogranitic compositions. We examined both volcanic and plutonic rocks with petrography and their textural variations with color cathodoluminescence, and used whole rock element and Sr, Nd and Pb isotope geochemistry to constrain magma compositions and origins. Electron microprobe analyses on feldspars have been completed to

The application of mathematical transformation in order to define edges of pluton Valja Strž

Directory of Open Access Journals (Sweden)

Ignjatović Snežana M.

2014-01-01

Full Text Available The Timok Magmatic Complex (TMC belongs to the East Serbian and is the largest volcanic area in our country. The largest pluton in this area is Valja Strž. This pluton is situated in the northwestern part of the complex. Applying different methods of mathematical transformation on aeromagnetic data facilitated outlining of pluton edges in subsurface of surrounding rocks. In this paper we used mathematical transformation on anomaly values of the magnetic field, obtained from processing of aeromagnetic data. In order to detect the edges of pluton Valja Strž we used following set of mathematical transformation: first vertical derivative, the total horizontal derivative, tilt derivative, upward continuation, and combination of upward continuation and tilt derivative. Results of application of mathematical transformation showed that outspread of the pluton Valja Strž in the subsurface is larger than its extend on the surface.

Deslumbramientos del mercado

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Monique Selim

2006-07-01

Full Text Available Con eje en los diferentes aspectos que adopta el actual proceso de mundialización de la lógica del mercado y expansión capitalista, aún en países socialistas, el presente artículo plantea la necesidad de una reflexión antropológica susceptible de articular el surgimiento de nuevas formas de dominación y representación simbólicas. Se discute el aparente efecto de unificación intelectual producido por la hegemonía del mercado respecto de hechos sociales heterogéneos dados en la historia reciente de las sociedades contemporáneas. Así, la renovada atracción que ejercen los nuevos escenarios sociales reconfigurados en virtud de las modalidades específicas de encarnación y operación de los procesos globalizantes, llama al estudio antropológico de las coyunturas. La autora despliega una interpretación del socialismo de mercado, conjunción -siempre en tensión- de un monopolio político estatal y una liberalización del mercado económico. En esta perspectiva se reubica el interés de una antropología del presente en relevar localmente, en este caso en Vietnam del Norte, la conformación de un nuevo mercado de demandas simbólicas, donde la reaparición de las prácticas culturales de comunicación con los antepasados expresa la necesidad de reunificación familiar y reconciliación con los muertos en la "larga guerra".Tendo como eixo os aspectos diferentes que adota o processo atual de mundialização da lógica do mercado e de expansão capitalista, até mesmo nos países socialistas, este artigo propoe a necessidade de uma reflexão antropológica capaz de articular o aparecimento de novas formas de dominação e de representação simbólica. Discute-se o efeito de superfície de unificação intelectual causado pela hegemonia do mercado em fatos sociais diversos em sociedades contemporâneas. Assim, a atração renovada de novos fatos sociais pelos modos específicos de incorporação e operação de processos de globaliza

Geological, geochemical and isotopic characteristics of the Archaean Kaap Valley pluton, Barberton mountain land, South Africa

International Nuclear Information System (INIS)

Robb, L.J.; Barton, J.M. Jr.; Kable, E.J.D.; Wallace, R.C.

1984-01-01

The Kaap Valley pluton consists predominantly of a homogeneous weakly foliated, hornblende-bearing tonalite. It is among the oldest granitoid bodies yet recognized in the environs of the Barberton greenstone belt, yielding 207 Pb/ 206 Pb mineral ages of about 3300 Ma and a Rb-Sr whole rock isochron age of about 3500 Ma. The Kaap Valley pluton is distinctive in many respects. Whereas all other gneiss plutons in the area are characterized by a trondhjemitic bulk composition with mafic mineralogies dominated by biotite, the Kaap Valley pluton is tonalitic in bulk composition with hornblende (plus minus minor biotite) as its major mafic phase. In this paper, the results of a detailed geological, geochemical and Pb-isotopic study of the Kaap Valley pluton are presented. Questions relating to the origin of the body are considered, with an emphasis on the formation of a tonalitic magma which is more mafic than those typically encountered in the region. Although exposure does not permit a detailed structural study of the gneiss pluton consideration is given to its mode of emplacement

Mercado municipal Can Vidalet

OpenAIRE

Romero Francisco, Jorge

2006-01-01

La intención del nuevo mercado municipal de Can Vidalet es crear un escenario en sombra, envuelto por una piel permeable; una "cesta" dentro de la cual se produce una actividad comercial. La topografía del lugar permite establecer un esquema comercial en sección, situando el mercado tradicional en cota superior y el nuevo uso comercial en planta baja, a nivel de plaza pública.

Alternativas para incrementar la liquidez del mercado de energía mayorista colombiano: el caso del mercado no regulado

OpenAIRE

García Gómez, Diego Felipe; Mejía Sierra, Diego Fernando

2013-01-01

El presente estudio tiene como objetivo la presentación de alternativas que contribuyan a aumentar la liquidez del mercado no regulado de energía eléctrica en Colombia -- Para ello se parte de una revisión general del mercado eléctrico colombiano, posteriormente se introduce el concepto liquidez, haciendo énfasis en la liquidez en mercados eléctricos y se referencian algunos mercados eléctricos desarrollados en Europa, Norte América, Países Nórdicos e Inglaterra -- Se concluye que es necesari...

Granitoid emplacement during syn-convergent transtension: An example from the Huamenlou pluton in North Qinling, central China

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Yang Li

2018-01-01

Full Text Available The Huamenlou pluton, is an elongated granite intrusion with high aspect ratio, emplaced within the southern margin of the North Qinling (central China. Here we investigate this pluton through multiple techniques including the fabric study, microstructural observation and zircon geochronology. Our zircon U–Pb data confirm that the granite crystallized at ca. 462 Ma which is consistent with the ages of other linear plutons in North Qinling. Microstructural observations of the Huamenlou granites illustrate that the pluton has undergone superimposed deformation during its emplacement, from magmatic to high-temperature solid state conditions. The internal fabric obtained by anisotropy of magnetic susceptibility (AMS and shape preferred orientation (SPO show similar results. The fabrics are relatively concordant and generally vary from NE–SW to NEE–SWW which are roughly oblique to the trend of the pluton elongation and the regional structures. Meanwhile, scalar parameters reflect two completely different strain regimes for the pluton and its host rocks, i.e., the fabrics within host rocks are mainly oblate while the central part of the intrusion displays mainly prolate fabrics. It is inferred that the structural pattern recorded in this pluton was caused by local dextral transtension in consequence of oblique convergence between the South and North China Blocks. We propose that the local transtension in convergence setting probably evolved from vertical extrusion tectonics that provided room for the magma emplacement and imparted prolate fabrics in the Huamenlou pluton.

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

International Nuclear Information System (INIS)

Gomez Rifas, C.; Heinzen, W.; Theune, C.

1980-01-01

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.

Strontium and oxygen isotopic variations in mesozoic and tertiary plutons of central Idaho

International Nuclear Information System (INIS)

Fleck, R.J.; Criss, R.E.

1985-01-01

Regional variations in initial 87 Sr/ 86 Sr ratios (rsub(i)) of Mesozoic plutons in central Idaho locate the edge of Precambrian continental crust at the boundary between the late Paleozoic-Mesozoic accreted terranes and Precambrian sialic crust in western Idaho. The rsub(i) values increase abruptly but continuously from less than 0.704 in the accreted terranes to greater than 0.708 across a narrow, 5 to 15 km zone, characterized by elongate, lens-shaped, highly deformed plutons and schistose metasedimentary and metavolcanic units. The chemical and petrologic character of the plutons changes concomitantly from ocean-arc-type units to a weakly peraluminous, calcit to calcalkalic suite. Plutons in both suites yield Late Cretaceous ages, but Permian through Early Cretaceous bodies are confined to the accreted terranes and early Tertiary intrusions are restricted to areas underlain by Precambrian crust. The two major terranes were juxtaposed between 75 and 130 m.y. ago, probably between 80 and 95 m.y. Oxygen and strontium isotopic ratios and Rb and Sr concentrations of the plutonic rocks document a significant upper-crustal contribution to the magmas that intrude Precambrian crust. Magmas intruding the arc terranes were derived from the upper mantle/subducted oceanic lithosphere and may have been modified by anatexis of earlier island-arc volcanic and sedimentary units. (orig./PW)

Análisis de la estabilidad del cerro Shishio mediante el empleo de técnicas numéricas

OpenAIRE

Vintimilla Avila, Maribel Cristina

2011-01-01

La presente investigación analiza la estabilidad existente en el Cerro Shishio ubicado en el sector de La Josefina por medio de técnicas numéricas. El deslizamiento del cerro Shishio provocado por el desfogue de las aguas represadas por el deslizamiento del cerro Tamuga, se originó en el material de la Formación Tarqui, el mismo que se deslizó sobre un roca intrusiva muy alterada. En la actualidad se puede observar el material deslizado acumulado al pie del talud, que ahora sirve de soporte ...

O mercado voluntário de carbono

OpenAIRE

Silva, Carlos Filipe Araújo da

2012-01-01

O objecto desta dissertação é caracterizar, em termos económicos, o problema que está subjacente à instituição dos mercados das licenças de carbono e a natureza económica deste tipo de solução para esse problema, dando-se, depois, uma atenção especial ao Mercado Voluntário. Para este tipo de mercado descreve-se o seu funcionamento e apresenta-se um projecto elaborado para uma federação de organizações de produtores florestais que poderia ser submetido a esse tipo de mercado....

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.

Subsurface profiling of granite pluton using microtremor method: southern Aravalli, Gujarat, India

Science.gov (United States)

Joshi, Aditya U.; Sant, Dhananjay A.; Parvez, Imtiyaz A.; Rangarajan, Govindan; Limaye, Manoj A.; Mukherjee, Soumyajit; Charola, Mitesh J.; Bhatt, Meghnath N.; Mistry, Sagar P.

2018-01-01

We report, using the microtremor method, a subsurface granitic pluton underneath the Narukot Dome and in its western extension along a WNW profile, in proximity of eastern fringe of Cambay Rift, India. The dome and its extension is a part of the Champaner Group of rocks belonging to the Mesoproterozoic Aravalli Supergroup. The present finding elucidates development of an asymmetric double plunge along Narukot Dome. Microtremor measurements at 32 sites were carried out along the axial trace (N95°) of the dome. Fourier amplitude spectral studies were applied to obtain the ratio between the horizontal and vertical components of persisting Rayleigh waves as local ambient noise. Fundamental resonant frequencies with amplitude ≥1-sigma for each site are considered to distinguish rheological boundary. Two distinct rheological boundaries are identified based on frequency ranges determined in the terrain: (1) 0.2219-10.364 Hz recorded at 31 stations identified as the Champaner metasediment and granite boundary, and (2) 10.902-27.1119 Hz recorded at 22 stations identified as the phyllite and quartzite boundary. The proposed equation describing frequency-depth relationship between granite and overlaying regolith matches with those already published in the literature. The morphology of granite pluton highlights the rootless character of Champaner Group showing sharp discordance with granitic pluton. The findings of manifestation of pluton at a shallower depth imply a steep easterly plunge within the Champaner metasediments, whereas signature of pluton at a deeper level implies a gentle westerly plunge. The present method enables to assess how granite emplacement influences the surface structure.

Panorama Pluton : a composite gabbro-monzodiorite early Ross Orogeny intrusion in southern Victoria Land, Antarctica

International Nuclear Information System (INIS)

Mellish, S.D.; Cooper, A.F.; Walker, N.W.

2002-01-01

The Koettlitz Glacier Alkaline Province of the Walcott Glacier to Radian Glacier area of the Transantarctic Mountains contains a diverse suite of intrusions ranging from gabbro and diorite to granite, nepheline syenite, and carbonatite. Most of the plutons are alkaline (A-type), although the Panorama Pluton is mafic, comprising both hypersthene normative gabbroic and quartz normative monzodioritic lithologies. The pluton has a composite nature, determined by whole-rock geochemical trends and Nd-Sr isotope data that reflect distinctive source regions for the different components. U-Pb geochronology of zircon and titanite indicates the Panorama Pluton was intruded during the early stages of the Neoproterozoic-early Paleozoic Ross Orogeny at 535 ± 9 Ma, and that it is coeval with the geochemically similar Dromedary Mafic Complex which crops out 10 km to the southeast. The Panorama Pluton is a volumetrically minor mafic component of the Koettlitz Glacier Alkaline Province, which predates, by at least 15 m.y., the dominant calc-alkaline suites that occur along-strike in the Dry Valleys area to the north, and the central Transantarctic Mountains to the south. The Panorama Pluton magmas, and other Koettlitz Glacier Alkaline Province lithologies, are interpreted to have formed in an extensional or transtensional jog that predates the onset of widespread Ross Orogeny subduction. (author). 48 refs., 7 figs., 3 tabs

Dos mercados en México

Directory of Open Access Journals (Sweden)

Ramírez Vázquez, Pedro

1966-06-01

Full Text Available Markets at la Lagunilla in Mexico City (San Camilito Four buildings have been erected at Ciudad de Mexico, San Camilito, to serve as zonal food market, furniture and home goods market, prepared foods market and clothes market. Between the four of them, they occupy a total surface of 33,300 m2 and a volume of 165,000 m3. The most interesting feature of these buildings is the type of roof with which each has been fitted. Popular market, at Coyoacan The various zones of this market, namely, selling hall, children's nursery, and general services, indicate clearly, both because of their shape and size, their specific function. The selling zone is outstanding because of the roof, formed by a number of hyperbolic paraboloids, made with lightweight concrete.Mercado de La Lagunilla en la Ciudad de México, San Camilito Han sido construidos en la ciudad de México, San Camilito, cuatro edificios destinados, respectivamente, a mercado— de Zona—de alimentos, mercado de muebles y artículos para el hogar, mercado de alimentos preparados, y mercado de ropas y telas. Ocupan entre todos ellos una superficie total de 33.200 m2 y un volumen de ies.165.000 m3. Lo más interesante de cada uno de estos edificios es el tipo de cubierta adoptado en cada caso. Mercado popular, en Coyoacán Las distintas zonas que componen este mercado, es decir, sala de ventas, guardería, servicios generales, etc., acusan, tanto en planta como en volumen, las funciones que tienen lugar en las mismas. En la sala de ventas destaca la estructura de su cubierta, constituida por una serie de paraboloides hiperbólicos construidos a base de hormigón ligero.

Mercado primario de valores negociables

OpenAIRE

Alonso Espinosa, Francisco José

1994-01-01

Estudio del régimen del mercado primario de valores según la Ley 24/1988, del Mercado de Valores y el RD 291/1992, de 27 de marzo. Caracterización de los valores negociables y estudio del régimen de la oferta pública de suscripción de valores negociables.

Crimes contra o mercado de capitais

OpenAIRE

Leonardo Alonso

2009-01-01

A necessidade de tutela eficiente do Mercado de Capitais é, atualmente, indiscutível. O advento de novas tecnologias e o tráfego internacional de capital cada vez maior; tornam o Mercado de Capitais, contemporaneamente, sujeito a amplos riscos e danos. Nesse contexto, o legislador tem respondido com a incriminação de condutas ofensivas ao mercado, contudo a formulação de tipos penais nem sempre se mostra adequada. Dessa forma, questiona-se qual o bem juridicamente tutelado pelos crimes contra...

Thermal modification of hematite-ilmenite intergrowths in the Ecstall pluton, British Columbia, Canada

DEFF Research Database (Denmark)

Brownlee, S.J.; Feinberg, J.M.; Harrison, R.J.

2010-01-01

In this study, we examine the effects of reheating on finely exsolved hematite-ilmenite intergrowths from the similar to 91 Ma Ecstall pluton using reflected light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). As a result of the emplacement of the you......In this study, we examine the effects of reheating on finely exsolved hematite-ilmenite intergrowths from the similar to 91 Ma Ecstall pluton using reflected light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). As a result of the emplacement...... of the younger adjacent similar to 52 Ma Quottoon pluton, samples closer to a thermal boundary have experienced greater degrees of thermal alteration. Five main microstructural features characterize hematite-ilmenite intergrowths from the Ecstall: (I) exsolution lamellae of hematite and ilmenite; (II) oxidation....... Higher temperatures also enhanced oxidation in ilmenite. The formation of magnetite altered the bulk magnetic properties of these samples, increasing NRM intensity. This study underscores the need to consider a pluton's post-emplacement thermal history before making tectonic interpretations based...

Oster pluton (Central Karelia) - the ancient massif of two-feldspar granites of Baltic Shield

International Nuclear Information System (INIS)

Kovalenko, A.V.; Rizvanova, N.G.

2000-01-01

Geochronological study of two-feldspar granites forming the Oster pluton in the Central Karelia was performed using the methods of U-Pb- and Sm-Nd-dating. U-Pb isotope data for zircons from granite of the Oster pluton correspond to the age of 2876±21 mln. years, whereas Sm-Nd isotope data obtained for three samples of the garnet correspond to the age varying from 3.0 to 3.5 bln. years. The ancient age of granites of the Oster pluton is explained by the presence of a sufficiently powerful crust in the region by that moment [ru

Radiogeologic assessment for nuclear waste isolation: studies of the Stripa pluton

International Nuclear Information System (INIS)

Wollenberg, H.; Flexser, S.; Andersson, L.

1982-01-01

To properly characterize candidate sites for radioactive waste isolation, it will be necessary to obtain a good understanding of their radiogeologic settings. The distribution and abundance of the naturally occurring radioelements - 238 U, 232 Th, their daughters, and 40 K, both in the rock mass encompassing the repository and in the neighboring rocks - constitute the baseline upon which the effects of the radioactive waste are superimposed. The distribution of these radioelements is also a good indicator of the geochemical homogeneity of the rock mass. At the Stripa experimental facility in an inactive iron mine in central Sweden, radiogeologic studies included gamma-spectrometric surveys, on the surface and underground, of the U, Th, and K contents of the quartz monzonite pluton encompassing the experiments, the high-grade metamorphic rocks surrounding the pluton, and the neighboring larger granitic plutons. The gamma-spectral surveys were calibrated by laboratory analyses of hand specimens and drill cores, permitting calculation of radioelement concentrations from field counting rates

en el mercado de Estados Unidos

Directory of Open Access Journals (Sweden)

Nadima Simón Domínguez

2004-01-01

Full Text Available El objetivo de este artículo es analizar el comportamiento de las exportaciones del sector de prendas de vestir (de tejido de punto y de tejido plano en el mercado de Estados Unidos (EUA durante el periodo de 1990 a 2002. Se identifican los principales competidores, las características de ambos mercados y los instrumentos de política comercial utilizados por las empresas estadounidenses para la protección de su industria textil. De igual forma, se hace un análisis de los principales productos de prendas de vestir que nuestro país exportó a EUA clasificándolos por su participación en el mercado de dicho país y por el dinamismo que presentan éstos. También se identifican los factores que inciden en la participación de México en el mercado estadounidense. Se concluye que México incrementó considerablemente sus exportaciones de prendas de vestir a EUA después de la entrada en vigor del TLCAN y de la devaluación del peso mexicano de diciembre de 1994. México es líder en el mercado de aquel país en camisas de algodón y en pantalones de mezclilla, seguido muy de cerca por China. Para mantener la participación de las prendas de vestir de México en dicho mercado, nuestra industria del vestido debe orientarse a la fabricación de paquete completo y de productos de moda con mayor valor agregado.

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

Energy Technology Data Exchange (ETDEWEB)

Ingle, J.C. Jr.

1982-01-01

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

LA-ICPMS zircon U-Pb age of Maofeng pluton of uranium deposit No.337 and its significance

International Nuclear Information System (INIS)

Zhang Zhanshi; Hua Renmin; Yao Junmin; Gu Shengyan; Deng Ping; Wu Lieqin

2007-01-01

Maofeng pluton is the most important uranium-host granite in Xiazhuang uranium orefield. The accurate granite formation age and its evolution history is crucial for understanding the mineralization in this district. LA-ICPMS zircon dating was applied in this paper and found the formation age of Maofeng pluton is 238.2 ± 2.3 Ma which suggests that Maofeng pluton was produced in the Indosinian magmatic event. Uranium mineralization age of No.337 deposit is commonly recognized to be 138 Ma. Therefore No.337 uranium deposit was not the typical magma hydrothermal deposit due to the long time gap between the pluton formation and the uranium mineralization. (authors)

Geology of the plutonic basement rocks of Stewart Island, New Zealand

International Nuclear Information System (INIS)

Allibone, A.H.; Tulloch, A.J.

2004-01-01

Exposures of basement rocks on Stewart Island provide a c. 70 km long by 50 km wide map of part of the Median Batholith that spans the margin of the Western Province. Because of their distance from the present plate boundary, these rocks are relatively unaffected by Cenozoic tectonism, allowing examination of unmodified Carboniferous-Cretaceous relationships within the Median Batholith. Thirty individual plutons (>c.20 km 2 ) have been mapped along with numerous relatively small intrusions ( 2 ). The large plutons form 85-90% of the Median Batholith on Stewart Island while the many smaller intrusions comprise 10-15%, mostly in the north. Lithologies include: biotite ± minor hornblende granodiorite, granite and leucogranite with accessory titanite - magmatic epidote and allanite (c. 50%); biotite ± muscovite ± garnet granite with S-type affinities (c. 10%); alkaline quartz monzonite, granite, and alkali feldspar granite with rare aegirine and blue-green amphibole (c. 3%); quartz monzodiorite and diorite with hornblende > biotite (c. 23%); gabbro and anorthosite (c. 12%) and ultramafic rocks (c. 2%). U-Pb zircon and monazite dating indicates that c. 12% of these plutonic rocks were emplaced during the Carboniferous between 345 and 290 Ma, c. 20% in the Early-Middle Jurassic at c. 170-165 Ma, c. 30% in the latest Jurassic to earliest Cretaceous between 152 and 128 Ma, and c. 38% in the Early Cretaceous between 128 and 100 Ma. The distribution of Pegasus Group schists and peraluminous granitoid rocks indicates that the northern limit of extensive early Paleozoic Western Province basement is located either within the Gutter Shear Zone or at the Escarpment Fault, 10-15 km south of the Freshwater Fault System previously thought to mark this boundary. Carboniferous and Middle Jurassic magmatism extended plutonic basement northwards as far as the Freshwater Fault System, while further magmatism during the latest Jurassic and earliest Cretaceous produced the basement

Amphibole Thermometry and a Comparison of Results from Plutonic and Volcanic Systems

Science.gov (United States)

Sherman, T. M.; Putirka, K. D.; De Los Reyes, A. M. A.; Ratschbacher, B. C.

2015-12-01

Recent work (Ridolfi and Renzulli 2014) shows that amphiboles can be used to infer magmatic temperatures, even without knowledge of co-existing liquids. Here, we apply this approach, using new calibrations, to investigate felsic-mafic magma interactions, in a volcanic (Lassen Volcanic Center, a Cascade volcano) and plutonic (the Jurassic Guadalupe Igneous Complex) system. Preliminary data suggest that volcanic processes, as might be expected, preserve higher temperatures than plutonic materials (on average, volcanic amphiboles recorded 907±57.3°C while plutonic amphiboles recorded 764±59.7°C). We also find that the average T of a given mineral grain decreases with increased mineral size such that those crystallized below 800°C sometimes reach sizes beyond ~1mm, while those near 900°C appear truncated to ~0.3mm. It is not clear if T is the only control on amphibole crystal growth; however, our results would imply that larger grains not only require more time to grow but require continued undercooling. Significant cooling or heating is also recorded in many volcanically- and plutonically-grown grains, which may reflect transitioning between magmas of different T and composition. Core-to-rim cooling trends (with a common T of drop of 80oC) likely represent mafic-to-felsic magma transitions, whereas core-to-rim heating of similar magnitudes indicate a felsic-mafic transition. Some grains, though, exhibit a constant T (in the range 700-900°C) from core to rim, which perhaps indicates some shielding from magma mixing processes. Amphiboles might thus provide a reliable record of the intensity of magma mingling and mixing experienced by any particular enclave. Interestingly, volcanically-derived amphiboles appear to mostly record cooling towards the rims, while their plutonic counterparts tend to experience heating. It would thus appear that at Lassen, amphiboles are unaffected by later mafic magma recharge, but at the GIC, the plutonic amphiboles are more likely to

Discussion on the petrochemistry characteristics and uranium deposit of Xiazhuang pluton in northern Guangdong province

International Nuclear Information System (INIS)

Wu Jiguang

2011-01-01

The element characteristic of Indo-Chinese epoch Xiazhuang granite is rich in silicon (SiO 2 =69.13%∼73.39%), alkalis (K 2 O+Na 2 O=7.49%∼8.69%), the ASI=1.01∼1.21 and ratio of w (K 2 O)/w (Na 2 O)>1, Xiazhuang pluton is belong to high potassium calcium-alkaline and aluminous series rocks. It shows that the pluton is typical S-type granite, little part is A-type granite character. Under the extension tectonic setting of lithosphere, the Xiazhuang pluton is partial melting product that making up metamorphic mud and sandstone together. By analysing the tectonic setting,the pluton is belong to post-collision granite that original rock provide abundant of uranium content for granite and the tectonic setting of forming provide the moving channels and occurrence space for uranium deposit. (authors)

U-Pb and Rb-Sr geochronology of the Wedgeport granitoid pluton, southwestern Nova Scotia

International Nuclear Information System (INIS)

Cormier, R.F.; Keppie, J.D.; Odom, A.L.

1988-01-01

Zircons from biotite monzogranite of the Wedgeport Pluton, intrusive into deformed metasediments of the Cambrian(?) Goldenville formation in the southwestern Meguma Terrane of Nova Scotia, yield concordant U-Pb ages of 316 ± 5 Ma. This is interpreted as the time of intrusion and crystallization. Within the error limits, the 323 ± 0.0056 Rb-Sr analyses of mineral separates of biotite, potassium feldspar, and quartz-plagioclase from several samples yield subparallel, internal isochrons with an average age of 257 ± 8 Ma. Initial ratios of the internal isochrons range from 0.716 to 0.759. A slow-cooling model for the latter data is discarded because the mineral data fall on straight lines. Instead, a reheating event related to plutonism ca 257 Ma ago, which was sufficient to cause local grain-to-grain migration and reequilibration of strontium and rubidium but not large-scale redistribution, is invoked. This reheating is also inferred to be responsible for the hydrothermal alteration and Sn-U mineralization concentrated along the northwestern margin of the pluton. A dextral northeast-southeast shear zone cutting the pluton is also inferred to be ca. 257 Ma old. It may be related to the last stages of westward abduction of the Meguma Terrane. These results provide a clear example of Permo-Carboniferous plutonism in the southwestern Meguma Terrane and suggest a similar interpretation may apply to other anomalously young ages recorded in this area. In light of these results, the Permo-Carboniferous age of the large East Kemptville tin deposit and its location in a dextral shear zone suggest that the association of younger plutonism and shear zones may be a significant factor for economic mineralization. (22 refs., 4 tabs., 3 figs.)

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

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

International Nuclear Information System (INIS)

Massa, E.

1984-01-01

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

Exploration and development of the Cerro Prieto geothermal field

Energy Technology Data Exchange (ETDEWEB)

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

1983-07-01

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

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.

Quantifying the Plutonic to Volcanic Relationship Along the Puna Plateau: Implications for Cordilleran Plateau Evolution

Science.gov (United States)

Ward, K. M.; Delph, J. R.; Zandt, G.; Beck, S. L.; Ducea, M. N.

2016-12-01

Quantifying well constrained plutonic to volcanic (P:V) ratios is inherently difficult because the tectonic processes that exhume intrusive bodies rarely preserve their extrusive equivalents. Conversely, active magmatic systems that have well-preserved volcanic deposits require sophisticated geophysical or geochemical approaches to estimate their plutonic roots and even when these sophisticated approaches are available, it is not always clear what constitutes a plutonic volume. Further complicating the enigmatic plutonic to volcanic relationship is the highly episodic nature of pluton emplacement where magmatic flare-ups produce several orders of magnitude more magmatism when compared against magmatic lulls. Despite this inherent difficulty, a growing body of independently measured P:V ratios (e.g. seismic tomography, geomorphic modeling, geological mapping/dating, and Zircon age spectra modeling) suggests the contribution of magmatic addition as an uplift mechanism in Cordilleran systems is much larger than is currently accepted. However, it remains unclear if these studies can be generalized to represent type behavior in Cordilleran systems or result from the non-uniform sampling imposed by the ability to measure large P:V ratios in only a few select and potentially anomalous regions of the American Cordillera. To better examine the role of magmatic processes in building Cordilleran high plateaus, we image the crustal seismic shear-wave velocity for an 800 km section (20.5°-28°S) of the active South American Cordillera (Puna Plateau). When placed in the context of existing geological and geophysical datasets, our seismic model reveals numerous mid-crustal low-velocity zones that we unambiguously interpret as the plutonic underpinnings associated with the voluminous silicic volcanics of the Puna Plateau. These larger P:V ratios are consistent with recent thermomechanical modeling of granitic magma intrusions that support the existence of long-lived, partially

U-Pb zircon dating of the Bassies granite (Pyrenees): a syn-tectonic pluton of Westphalian age

International Nuclear Information System (INIS)

Paquette, J.L.

1997-01-01

A new U-Pb zircon age of 312 ± 2 Ma for the Bassies pluton (Pyrenees) contradicts the previous whole-rock Rb-Sr dating at 276 ± 16 Ma, which was considered as the age of emplacement, therefore regarded as post-tectonic. The new date is in agreement with recent structural studies which suggest a Hercynian syn-tectonic emplacement for the Bassies pluton. These results strengthen the few U-Pb ages already published for the Pyrenean granites and indicate that the Hercynian plutonism of the Pyrenees is essentially Carboniferous in age and syn-tectonic. (authors)

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

International Nuclear Information System (INIS)

Heinzen, W.; Santana, I.; Mari, C.

1986-01-01

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.

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

International Nuclear Information System (INIS)

Lopez-del-Rio, H.; Mireles-Garcia, F.; Mendez-Cardona, R.Y.; Nicolas-Caretta, M.; Speakman, R.J.; Glascock, M.D.

2009-01-01

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.)

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.)

Reconnaissance geochemical exploration of plutons of syenite and shonkinite, southern Asir, Kingdom of Saudi Arabia

Science.gov (United States)

Overstreet, W.C.; Assegaff, A.B.; Hussain, M.A.; Naqvi, M.I.; Selner, G.I.; Matzko, J.J.

1985-01-01

Reconnaissance geochemical exploration for rare metals in plutons of syenite and shonkinite disclosed generally less than 20 ppm Nb in rocks, wadi sediments, and concentrates. The sparsity of Nb is accompanied by low values for La, Sn, W, Y, and Zr and relatively high but insignificant values for Be and Mo. Base and precious metals are either below their respective limits of determination in the various sample media or are present at background levels commensurate with average crustal abundances in felsic rocks. Pegmatite dikes associated with the syenite plutons are rare and lack vermiculite. The present investigation disclosed no possible ore deposits in the plutons covered by the field work.

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

Science.gov (United States)

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

2009-05-01

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

Report of the Cerro Chato ultrabasic geophysical studies

International Nuclear Information System (INIS)

Cicalese, H.; Mari, C.; Lema, F.; Valverde, C.; Haut, R.

1987-01-01

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.

Potassium, rubidium, strontium, thorium and uranium of the cretaceous plutons in the Kitakami Mountains

International Nuclear Information System (INIS)

Katada, Masato; Kanaya, Hiroshi.

1980-01-01

The Cretaceous plutonic rocks in the Kitakami Mountains, 110 to 125 Ma in K-Ar ages on biotite, etc., can be petrographically and petrochemically classified into seven groups; Zones I, II, III, IV, V, VIa and VIb. Some of them are arranged in the east to west direction. The plutons of Zones II and V are mainly felsic. They are of comparatively big dimension reaching 600 square kilometers. The plutons of other zones are composed of felsic and mafic rocks. They occur on a small scale. The plutonic rocks have been chemically analysed for CaO, K 2 O, Rb, Sr, Th, and U. In the mafic rocks of CaO > 8.2 percent, the contents of CaO and Na 2 O are nearly equal in each zone throughout the Kitakami Mountains. K 2 O, Rb, Th, and U contents, however, generally increase westward. Sr also does. In the westernmost zone, Zone IV, the mafic rocks resemble shoshonite concerning their major elements. Some of the plutons, especially in Zones II and V, are zonally divided into marginal and central facies. The two facies are different in their K 2 O, Rb, etc. contents, and K/Rb and other ratios. In the marginal facies K 2 O and Rb are richer and K/Rb is smaller than those in the central facies. This fact suggests the different processes of magmatic differentiation in the two facies. Intrusion of the marginal facies have successively followed by that of the central facies. (author)

LA CERÁMICA CERRO LOS HORNOS, PRESENCIA INKA EN LA COSTA DE TACNA, SUR DEL PERÚ

OpenAIRE

Vela Velarde, Carlos

2004-01-01

Se estudia el sitio Cerro Los Hornos, ubicado en la costa de Tacna, sur del Perú. Presenta cerámica con filiación Inka Imperial o Cuzco Policromo, pero de fabricación local; esta presencia cultural es consecuencia del proceso de expansión Inka a la costa sur del Perú, la cual establece relaciones con la sociedad local The place studied is Cerro Los Hornos located in the coast of Tacna, south of Peru, presents ceramic with filiation Inka Imperial or Cuzco Policromo, but of local production;...

The last glacial cycle and palaeolake synchrony in the southern bolivian Altiplano: Cerro Azanaques case study

Directory of Open Access Journals (Sweden)

1995-01-01

Full Text Available SYNCHRONISME ENTRE LE DERNIER CYCLE GLACIAIRE ET L'EXTENSION DES PALÉOLACS DANS LE SUD DE L'ALTIPLANO BOLIVIEN : EXEMPLE DU CERRO AZANAQUES. Dans la Cordillère Orientale, au niveau du Cerro Azanaques (18°S, Bolivie, des moraines, des sédiments glaciaires, des rivages paléolacustres, des deltas et des stromatolites qui se sont préservés, révèlent des conditions climatiques fortement différentes dans le passé. La culmination de la dernière avancée du glacier Lijunimani a été datée par la méthode du radiocarbone à 13 000 ans BP à partir de sédiments glaciaires ayant remanié un horizon organique de tourbe. La cartographie de cette diacmitite argileuse particulière révèle un delta en forme de cône bordé par un glacier cela montre que les glaciers et les anciens systèmes lacustres font partie d'un processus d'expansion simultanée. L'étude stratigraphique détaillée réalisée au Cerro Azanaques fournit de fortes évidences allant dans le sens d'une réponse commune des glaciers et des lacs à un signal piloté par un changement climatique les lacs ne sont donc pas le simple résultat de la fonte des glaciers des cordillères. SINCRONISMO ENTRE EL ÚLTIMO CICLO GLACIAL Y LA EXTENSIÓN DE LOS PALEOLAGOS EN EL SUR DEL ALTIPLANO BOLIVIANO: CASO DEL CERRO AZANAQUES. En la Cordillera Oriental, a la altura del Cerro Azanaques (18º S, Bolivia aparecen preservadas morrenas y sedimentos glaciares, líneas de costa paleolacustres, deltas y estromatolitos, lo que revela condiciones climáticas pasadas significativamente diferentes. La culminación del último avance del glaciar Lijunimani ha sido fechada mediante radiocarbono a 13 000 años BP a partir de sedimentos glaciares que han desplazado un horizonte orgánico de turba. La cartografía de esta particular diamictita arcillosa revela un delta en forma de abanico con hielo en sus márgenes lo que indica que los glaciares y los sistemas paleolacustres sufrieron un proceso

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

Depositional features and stratigraphic sections in granitic plutons: implications for the emplacement and crystallization of granitic magma

Science.gov (United States)

Wiebe, R. A.; Collins, W. J.

1998-09-01

Many granitic plutons contain sheet-like masses of dioritic to gabbroic rocks or swarms of mafic to intermediate enclaves which represent the input of higher temperature, more mafic magma during crystallization of the granitic plutons. Small-scale structures associated with these bodies (e.g. load-cast and compaction features, silicic pipes extending from granitic layers into adjacent gabbroic sheets) indicate that the sheets and enclave swarms were deposited on a floor of the magma chamber (on granitic crystal mush and beneath crystal-poor magma) while the mafic magma was incompletely crystallized. These structures indicate 'way up', typically toward the interior of the intrusions, and appear to indicate that packages of mafic sheets and enclave concentrations in these plutons are a record of sequential deposition. Hence, these plutons preserve a stratigraphic history of events involved in the construction (filling, replenishment) and crystallization of the magma chamber. The distinctive features of these depositional portions of plutons allow them to be distinguished from sheeted intrusions, which usually preserve mutual intrusive contacts and 'dike-sill' relations of different magma types. The considerable thickness of material that can be interpreted as depositional, and the evidence for replenishment, suggest that magma chamber volumes at any one time were probably much less than the final size of the pluton. Thus, magma chambers may be constructed much more slowly than presently envisaged. The present steep attitudes of these structures in many plutons may have developed gradually as the floor of the chamber (along with the underlying solidified granite and country rock) sank during continuing episodes of magma chamber replenishment. These internal magmatic structures support recent suggestions that the room problem for granites could be largely accommodated by downward movement of country rock beneath the magma chamber.

Mining inventory of Uruguay. Results of geochemical prospecting of Cerro Partido fotoplano

International Nuclear Information System (INIS)

Zeegers, H.; Artignan, D.; Vairon, P.

1982-01-01

This work is about the analitical results of the geological prospection carried out in Cerro Partido zone within the framework of Mining inventory of Uruguay. In this fotoplano (Esc. 1/50.000 and 1/400.000 there are metamorphic, mesozoic and carbonated formations

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.

Petrology and Geochemistry of Neoproterozoic Arc Plutons Beneath the Atlantic Coastal Plain, SRS, SC

Energy Technology Data Exchange (ETDEWEB)

Maryak, M.

1998-10-21

In this report is presented first a brief review of the regional geologic setting of the Savannah River Site, descriptions of the plutonic rock units sampled here, whole rock geochemical data on the plutonic igneous rocks, and finally, a discussion of how the crystalline basement rocks of the Savannah River Site formed and how they may correlate with other terranes exposed in the Piedmont of the Carolinas, Georgia, and Virginia.

U-Pb and K-Ar geochronology from the Cerro Empexa Formation, 1st and 2nd Regions, Precordillera, northern Chile

International Nuclear Information System (INIS)

Tomlinson, A.J; Martin, M.W; Blanco, N.; Perez de Arce, C

2001-01-01

The Cerro Empexa Formation (Galli, 1957) is a regionally distributed andesitic volcanic and continental sedimentary unit exposed in the Precordillera of the 1st and 2nd Regions of northern Chile. The formation has generally been considered to lie within the Lower or 'mid' Cretaceous, however, this assignment is based on scant, unreliable geochronologic data. Furthermore, there are conflicting interpretations as to whether the unit predates or postdates the first major Mesozoic shortening event affecting northern Chile. Because of the formation's presumed mid-Cretaceous age and its stratigraphic position over older back-arc sedimentary successions, the unit has been interpreted to represent products of the first eastward jump in the Andean magmatic arc from the arc's initial position in the Cordillera de la Costa (Scheuber and Reutter, 1992). In this paper we present the results of mapping and field observations that indicate exposures previously assigned to the Cerro Empexa Formation include two andesitic volcanic units separated by a major unconformity. The Cerro Empexa Formation proper lies above this unconformity. We also present U-Pb zircon and K-Ar geochronology that indicate the Cerro Empexa Formation is latest Cretaceous in its lower levels, and integrate our data with previously reported 40 Ar/ 39 Ar and fission-track data in the Cerros de Montecristo area (Maksaev, 1990; Maksaev and Zentilli, 1999) to show that 1800±600 m of rocks were deposited within ca. 2.5 m.y (au)

Syn-extensional plutonism and peak metamorphism in the albion-raft river-grouse creek metamorphic core complex

Science.gov (United States)

Strickland, A.; Miller, E.L.; Wooden, J.L.; Kozdon, R.; Valley, J.W.

2011-01-01

The Cassia plutonic complex (CPC) is a group of variably deformed, Oligocene granitic plutons exposed in the lower plate of the Albion-Raft River- Grouse Creek (ARG) metamorphic core complex of Idaho and Utah. The plutons range from granodiorite to garnet-bearing, leucogranite, and during intrusion, sillimanite- grade peak metamorphism and ductile attenuation occurred in the country rocks and normal-sense, amphibolite-grade deformation took place along the Middle Mountain shear zone. U-Pb zircon geochronology from three variably deformed plutons exposed in the lower plate of the ARG metamorphic core complex revealed that each zircon is comprised of inherited cores (dominantly late Archean) and Oligocene igneous overgrowths. Within each pluton, a spread of concordant ages from the Oligocene zircon overgrowths is interpreted as zircon recycling within a long-lived magmatic system. The plutons of the CPC have very low negative whole rock ??Nd values of -26 to -35, and initial Sr values of 0.714 to 0.718, consistent with an ancient, crustal source. Oxygen isotope ratios of the Oligocene zircon overgrowths from the CPC have an average ??18O value of 5.40 ?? 0.63 permil (2SD, n = 65) with a slight trend towards higher ??18O values through time. The ??18O values of the inherited cores of the zircons are more variable at 5.93 ?? 1.51 permil (2SD, n = 29). Therefore, we interpret the plutons of the CPC as derived, at least in part, from melting Archean crust based on the isotope geochemistry. In situ partial melting of the exposed Archean basement that was intruded by the Oligocene plutons of the CPC is excluded as the source for the CPC based on field relationships, age and geochemistry. Correlations between Ti and Hf concentrations in zircons from the CPC suggest that the magmatic system may have become hotter (higher Ti concentration in zircon) and less evolved (lower Hf in zircon concentration) through time. Therefore, the CPC represents prolonged or episodic magmatism

Mercado municipal en Sant Quirze

OpenAIRE

Redondo Díez, Laura

2010-01-01

El proyecto satisface la necesidad de un Mercado Municipal en Sant Quirze. Situado en el actual recinto ferial del pueblo, el parque de la Betzuca, un punto céntrico cerca del casco antiguo y de las nuevas urbanizaciones. Las condiciones del lugar enriquecen el proyecto permitiendo usos múltiples muy adecuados a cada banda del solar: zona de mercado, galerías exteriores, supermercado, guardería, restaurante y bares vinculados a la zona del río, almacenes, zonas de carga y descarga y un gra...

Searching pristine source of two gabbric plutons outcroping in Central Sierras Pampeanas Range, Argentina

International Nuclear Information System (INIS)

Daziano, C.; Ayala, R.

2010-01-01

This work is about the study of two gabbric plutons outcrop ing throughout Central Sierras Pampeanas range (Cordoba province, Argentina). San Lorenzo hill gabbric plutons is in the Upper proterozoic age whereas Cañada del Puerto belongs to the Early proterozoic.They are stock-type igneous bodies and they are intrusive s in an Upper Precambrian crystalline basement; it is mainly composed by gneisses, migmatites, schistes, marbles, amphibolite s, tact's, serpentinites and related rocks

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)

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

International Nuclear Information System (INIS)

Lopez del Rio, H.; Mireles G, F.; Mendez C, R. Y.; Nicolas C, M.; Speakman, R. J.; Glascock, M. D.

2009-10-01

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)

Contribution to the radioactivity of Um Ara granitic pluton, south-eastern desert, Egypt

International Nuclear Information System (INIS)

El Reedy, M.W.; Kamel, A.F.; Mansour, S.E.I.

1988-01-01

Um Ara area lies in the southern part of the eastern desert between latitudes 22 0 30' and 22 0 41'N and longitudes 33 0 46' and 33 0 54'E. Several types of granitic varieties ranging from high silica granite (SiO 2 >75%) to low silica granite (SiO 2 68-70%) occur in Um Ara granitic pluton. Surface samples were collected from the high anomalous locations in the pluton together with trenches samples (about 50cm in depth). The U content in the surface samples ranges from 69 to 7 ppm while in trenches samples, it ranges from 38 to 759 ppm. The thorium content on the other hand ranges from 34 to 402 ppm in surface samples and from 158 to 316 ppm in trenches samples. Some samples show no Th contents. The Th/U ratios ranges from 0.065 to 3.137 in surface samples and from 0.386 to 2.590 in trenches samples. An enrichment of U content is the main feature characterising this granitic pluton, it is mainly connected with the fractured zones. Uranium is mostly present as secondary U mineralization accompanied by Fe, Mn and to some extent by carbonate materials. A hydrothermal origin could be considered for this U mineralization in the pluton. Primary U mineralization (pitchblende) together with secondary mineralization was observed in some locations in the area disseminated in the granite, this reflects the syngenetic origin of this granitic type

Magma-Tectonic Interactions along the Central America Volcanic Arc: Insights from the August 1999 Magmatic and Tectonic Event at Cerro Negro, Nicaragua

Science.gov (United States)

La Femina, P.; Connor, C.; Strauch, W.

2002-12-01

Volcanic vent alignments form parallel to the direction of maximum horizontal stress, accommodating extensional strain via dike injection. Roughly east-west extension within the Central America Volcanic Arc is accommodated along north-northwest-trending basaltic vent alignments. In Nicaragua, these alignments are located in a northwest-trending zone of dextral shear, with shear accommodated along northeast trending bookshelf faults. The recent eruption of Cerro Negro volcano, Nicaragua and Marabios Range seismic swarm revealed the interaction of these fault systems. A low energy (VEI 1), small volume (0.001 km3 DRE) eruption of highly crystalline basalt occurred at Cerro Negro volcano, Nicaragua, August 5-7, 1999. This eruption followed three tectonic earthquakes (each Mw 5.2) in the vicinity of Cerro Negro hours before the onset of eruptive activity. The temporal and spatial pattern of microseismicity and focal mechanisms of the Mw 5.2 earthquakes suggests the activation of northeast-trending faults northwest and southeast of Cerro Negro within the Marabios Range. The eruption was confined to three new vents formed on the southern flank of Cerro Negro along a preexisting north-northwest trending alignment; the El Hoyo alignment of cinder cones, maars and explosion craters. Surface ruptures formed > 1 km south and southeast of the new vents suggest dike injection. Numerical simulations of conduit flow illustrate that the observed effusion rates (up to 65 ms-1) and fountain heights (50-300 m) can be achieved by eruption of magma with little or no excess fluid pressure, in response to tectonic strain. These observations and models suggest that 1999 Cerro Negro activity is an excellent example of tectonically induced small-volume eruptions in an arc setting.

Report of boring made in the South of Cerro Largo district (Cerro Largo) 1977-1978[Study of Uranium prospection in Uruguay]; Informe de los trabajos de perforacion efectuados en el distrito Cerro Largo Sur (Dpto. Cerro Largo) 1977 - 1978

Energy Technology Data Exchange (ETDEWEB)

Massa, E

1984-07-01

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.

Map showing the distribution and characteristics of plutonic rocks in the Tonopah 1 degree by 2 degrees Quadrangle, central Nevada

Science.gov (United States)

John, D.A.

1987-01-01

Plutonic rocks, mostly granite and granodiorite, are widely distributed in the west two-thirds of the Tonopah 1 degree by 2 degree quadrangle, Nevada. These rocks were systematically studied as part of the Tonopah CUSMAP project. Studies included field mapping, petrographic and modal analyses, geochemical studies of both fresh and altered plutonic rocks and altered wallrocks, and K-Ar and Rb-Sr radiometric dating. Data collected during this study were combined with previously published data to produce a 1:250,000-scale map of the Tonopah quadrangle showing the distribution of individual plutons and an accompanying table summarizing composition, texture, age, and any noted hydrothermal alteration and mineralization effects for each pluton.

The Cerro Grande Fire - From Wildfire Modeling Through the Fire Aftermath

Energy Technology Data Exchange (ETDEWEB)

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

2001-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2001-01-01

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

The Fontaine Pluton : an early Ross Orogeny calc-alkaline gabbro from southern Victoria Land, Antarctica

International Nuclear Information System (INIS)

Cottle, J.M.; Cooper, A.F.

2006-01-01

The Fontaine Pluton is a previously undescribed mafic intrusion outcropping at Fontaine Bluff on the south side of the Carlyon Glacier in southern Victoria Land, Antarctica. It is the southern-most member of a laterally extensive mafic suite emplaced at mid-crustal depths during the initial stages of the Ross Orogeny. The pluton comprises recrystallised hornblende-biotite gabbro, which in places shows well-defined centimetre to metre scale primary igneous layering. Recrystallised ultramafic enclaves composed of amphibole-chlorite-talc are inferred to be remnants of a chemically and mineralogically distinct cumulate fraction. The intrusion has a 87 Sr/ 86 Sr (i) ratio of 0.70679 and a 143 Nd/ 144 Nd (i) ratio of 0.51187 (εNd (i) = -1.2). This, coupled with other geochemical data, implies that the Fontaine Pluton was formed by c. 15% partial melting of a depleted mantle source that was subsequently contaminated by continental crust. Preliminary U-Pb geochronology on zircon suggests an emplacement age for the pluton of 546 ± 10 Ma. These new data indicate that Ross Orogeny magmatism in this area of southern Victoria Land was initiated in the late Neoproterozoic along a subducting plate margin. (author). 55 refs., 10 figs., 3 tabs

Death Valley turtlebacks: Mesozoic contractional structures overprinted by Cenozoic extension and metamorphism beneath syn-extensional plutons

Science.gov (United States)

Pavlis, T. L.; Miller, M.; Serpa, L.

2008-07-01

The term turtleback was first coined to describe the curvilinear fault surfaces that produced a distinctive geomorphic form in the Black Mountains east of Death Valley, and although it was decades before their full significance was appreciated, they remain one of the most distinctive features of the extensional structure of the Death Valley region. Historically the interpretation of the features has varied markedly, and misconceptions about their character continue to abound, including descriptions in popular field guides for the area. It the 1990's, however, the full history of the systems began to be apparent from several key data: 1) the dating of the plutonic assemblage associated with the turtlebacks demonstrated that late Miocene, syn-extensional plutonism was fundamental to their formation; 2) the plutonic assemblage forms an intrusive sheet structurally above the turtlebacks, indicating a tie between much of the high grade metamorphism and Cenozoic plutonism; 3) a modern analog for the syn-extensional plutonism in the Black Mountains was recognized beneath Death Valley with the imaging of a mid-crustal magma body; 4) the Neogene structural history was worked out in the turtlebacks showing that folding of early-formed shear zones formed the turtleback anticlinoria but overprinting by brittle faults produced the final form as they cut obliquely across the older structure; and 5) the pre-extensional structural history was clarified, demonstrating that Mesozoic basement-involved thrust systems are present within the turtlebacks, but have been overprinted by the extensional system. An unresolved issue is the significance of Eocene U-Pb dates for pegmatites within the region, but presumably these relate somehow to the pre-extensional history. Miller and Pavlis (2005; E. Sci. Rev.) reviewed many features of the turtlebacks, and our working model for the region is that the turtlebacks originated as mid-crustal ductile-thrust systems within the Cordilleran fold

Compositional Evolution of Pyrochlore-Group Minerals in Carbonatites of the Belaya Zima Pluton, Eastern Sayan

Science.gov (United States)

Khromova, E. A.; Doroshkevich, A. G.; Sharygin, V. V.; Izbrodin, L. A.

2017-12-01

Pyrochlore-group minerals are the main concentrators of niobium in carbonatites of the Belaya Zima alkaline pluton. Fluorcalciopyrochlore, kenopyrochlore and hydropyrochlore were identified in chemical composition. Their main characteristics are given: compositional variation, morphology, and zoning. During evolution from early calcite to late ankerite carbonatites, the UO2, TiO2, REE, and Y contents gradually increased. All carbonatite types are suggested to contain initial fluorcalciopyrochlore. However, in calcite-dolomite and ankerite carbonatites, it is partially or completely hydrated due to hydrothermal processes at the late stage of the pluton. This hydration resulted in the appearance of kenopyrochlore and hydropyrochlore due to removal of Ca, Na and F, and input of Ba, H2O, K, Si, Fe, and probably U and REE. At the last stage of the pluton, this hydrated pyrochlore was replaced by Fe-bearing columbite.

Investigation of the mineral potential of the Clipper Gap, Lone Mountain-Weepah, and Pipe Spring plutons, Nevada

International Nuclear Information System (INIS)

Tingley, J.V.; Maldonado, F.

1983-01-01

The Clipper Gap pluton, composed mostly of quartz monzonite with minor granite, granodiorite, and crosscutting alaskite dikes, intrudes Paleozoic western facies strata. A narrow zone of contact metamorphism is present at the intrusive-sediment contact. No mineral production has been recorded from Clipper Gap, but quartz veins containing gold-silver-copper mineral occurrences have been prospected there from the late 1800's to the present. Areas of the Lone Mountain-Weepah plutons that were studied are located in Esmeralda County about 14 km west of Tonopah, Nevada. At Lone Mountain, a Cretaceous intrusive cuts folded Precambrian and Cambrian sediments. Lead-zinc ores have been mined from small replacement ore bodies in the Alpine district, west of Lone Mountain. Copper and molybdenum occurrences have been found along the east flank of Lone Mountain, and altered areas were noted in intrusive outcrops around the south end of Lone Mountain. Mineral occurrences are widespread and varied with mining activity dating back to the 1860's. The Pipe Spring pluton study area is flanked by two important mining districts, Manhattan to the north and Belmont to the northeast. Mining activity at Belmont dates from 1865. Activity at Manhattan was mainly between 1907 and 1947, but the district is active at the present time (1979). Four smaller mining areas, Monarch, Spanish Springs, Baxter Spring, and Willow Springs, are within the general boundary of the area. The Pipe Spring pluton study area contains numerous prospects along the northern contact zone of the pluton. Tungsten-bearing veins occur within the pluton near Spanish Springs, with potential for gold-tungsten placer in the Ralston Valley. Nickel and associated metals occur at Willow Spring and Monarch Ranch, where prospects may be associated with the margin of the Big Ten Peak Caldera

Paleomagnetic and stable isotope study of the pluton at Rio Hondo near Questa, New Mexico: Implications for CRM related to hydrothermal alteration

Energy Technology Data Exchange (ETDEWEB)

Hagstrum, J T; Johnson, C M

1986-06-01

Paleomagnetic and rock magnetic data combined with stable isotope data from the middle Tertiary pluton along the Rio Hondo in northern New Mexico suggest that its magnetic remanence has both thermal (TRM) and high-temperature chemical (CRM) components. Oxygen isotope temperatures indicate that magnetite associated with the more rapidly cooled higher levels of the pluton, and with mafic inclusions and cogenetic rhyolitic dikes sampled at lower levels of exposure, ceased subsolidus recrystallization and isotopic exchange above its Curie temperature (580/sup 0/C) in the presence of a magmatic fluid. Continued cooling imparted a TRM to these portions of the pluton. The more slowly cooled granodiorite at lower levels has quartz-magnetite isotopic temperatures that are below the Curie temperature of magnetite implying that its magnetization is high-temperature CRM. Sub-Curie isotopic temperatures for other granitic plutons in the western U.S.A. suggest that CRM may be commonly derived from subsolidus interactions between magnetite and magmatic fluids in plutonic rocks. A meteoric-hydrothermal system generated by the cooling Rio Hondo pluton, and not by younger adjacent intrusions, resulted in limited alteration along zones of high permeability near the southern margin of the Rio Hondo pluton, and in more prevasive alteration of the pluton to the north. The meteoric-hydrothermal alteration occurred at relatively high temperatures (>350/sup 0/C) and, with the exception of local chloritization, caused little visible alteration of the rocks. The isotopic ratios indicate that little of the magnetite could have grown from or exchanged with a meteoric-hydrothermal fluid.

Characterizing and modelling the radionuclide transport properties of fracture zones in plutonic rocks of the Canadian Shield

International Nuclear Information System (INIS)

Davison, C.C.; Kozak, E.T.; Frost, L.H.; Everitt, R.A.; Brown, A.; Gascoyne, M.; Scheier, N.W.

1999-01-01

Plutonic rocks of the Canadian Shield were investigated as a potential host medium for nuclear fuel waste disposal of used CANDU nuclear fuel. Field investigations at several geologic research areas on the Shield have shown that major fracture zones are the dominant pathways for the large scale movement of groundwater and solutes through plutonic rock bodies. Because of this, a significant amount of the geoscience work has focused on methods to identify, characterize and model the radionuclide transport properties of major fracture zones in the fractured plutonic rocks of the Shield. In order to quantify the transport properties of such fracture zones a series of, groundwater tracer tests were performed over a period of several years in several major, low dipping fracture zones. Sixteen tracer tests were performed using dipole recirculation methods to evaluate transport over distance scales ranging from 17 m to 700 m. It was concluded that only tracer tests can provide useful estimates of the effective porosity and dispersivity characteristics of these large fracture zones in plutonic rocks of the Canadian Shield. (author)

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

Directory of Open Access Journals (Sweden)

Hernán Horacio Schiaffini

2011-12-01

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

Mercado de datos: conceptos y metodologías de desarrollo

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Ricardo Chinchilla Arley

2011-10-01

Full Text Available En este artículo se ofrece una descripción sobre la importancia del depósito y del mercado de datos. Además, identifican y formulan las principales definiciones, esquemas y términos básicos relacionados con el mercado de datos. Igualmente, se establecen y desarrollan los modelos de implementación y las metodologías para el desarrollo de un mercado de datos. Por último, se consideran las formas tecnológicas de procesamiento analítico en línea (OLAP y su utilidad en el análisis del mercado de datos.

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

OpenAIRE

Federico Fuentes; Victor A. Ramos

2008-01-01

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

Geochemical constraints on the link between volcanism and plutonism at the Yunshan caldera complex, SE China

Science.gov (United States)

Yan, Lili; He, Zhenyu; Beier, Christoph; Klemd, Reiner

2018-01-01

The Yunshan caldera complex is part of a larger scale, ca. 2000-km-long volcanic-plutonic complex belt in the coastal region of SE China. The volcanic rocks in the caldera complex are characterized by high-silica peraluminous and peralkaline rhyolites associated with an intracaldera porphyritic quartz monzonite pluton. In this study, we present zircon U-Pb, Hf and stable O isotopes along with geochemical data of both volcanic and plutonic rocks to evaluate the potential petrogenetic link between volcanism and plutonism in the Yunshan caldera complex. SHRIMP zircon U-Pb geochronology of both volcanic and plutonic rocks yields almost identical ages ranging from 95.6 to 93.1 Ma. The peraluminous and peralkaline rhyolites show negative anomalies of Sr, P, Ti and Ba and to a lesser extent negative Nb and Ta anomalies, along with positive Rb anomalies and `seagull-like' rare earth element (REE) patterns with negative Eu anomalies and low (La/Yb)N ratios. The intracaldera porphyritic quartz monzonite displays minor negative Rb, Nb, Ta, Sr, P and Ti anomalies and a positive Ba anomaly with REE patterns characterized by relatively high (La/Yb)N ratios and lack significant Eu anomalies. The peraluminous and peralkaline rhyolites and the porphyritic quartz monzonite exhibit consistent ɛ Nd( t) of - 3.7 to - 2.2 and display zircon ɛ Hf( t) values of - 2.1 to 3.7. They further have similar, mantle-like, zircon oxygen isotopic compositions (δ18OVSMOW mainly = 4.63 to 5.76‰). We interpret these observations to be in agreement with a crystal mush model in which the parental magma of the volcanic and plutonic rocks of the Yunshan caldera complex was likely produced by interaction of asthenosphere melts with subduction-influenced enriched mantle wedge. The peralkaline rhyolites are interpreted to represent the most differentiated magma that has subsequently experienced significant fluid-melt interactions, whereas the porphyritic quartz monzonite may be representative of the

Erupted frothy xenoliths may explain lack of country-rock fragments in plutons

Science.gov (United States)

Burchardt, Steffi; Troll, Valentin R.; Schmeling, Harro; Koyi, Hemin; Blythe, Lara

2016-01-01

Magmatic stoping is discussed to be a main mechanism of magma emplacement. As a consequence of stoping, abundant country-rock fragments should occur within, and at the bottom of, magma reservoirs as “xenolith graveyards”, or become assimilated. However, the common absence of sufficient amounts of both xenoliths and crustal contamination have led to intense controversy about the efficiency of stoping. Here, we present new evidence that may explain the absence of abundant country-rock fragments in plutons. We report on vesiculated crustal xenoliths in volcanic rocks that experienced devolatilisation during heating and partial melting when entrained in magma. We hypothesise that the consequential inflation and density decrease of the xenoliths allowed them to rise and become erupted instead of being preserved in the plutonic record. Our thermomechanical simulations of this process demonstrate that early-stage xenolith sinking can be followed by the rise of a heated, partially-molten xenolith towards the top of the reservoir. There, remnants may disintegrate and mix with resident magma or erupt. Shallow-crustal plutons emplaced into hydrous country rocks may therefore not necessarily contain evidence of the true amount of magmatic stoping during their emplacement. Further studies are needed to quantify the importance of frothy xenolith in removing stoped material. PMID:27804996

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.

Geographically diverse Australian isolates of Melissococcus pluton exhibit minimal genotypic diversity by restriction endonuclease analysis.

Science.gov (United States)

Djordjevic, S P; Smith, L A; Forbes, W A; Hornitzky, M A

1999-04-15

Melissococcus pluton, the causative agent of European foulbrood is an economically significant disease of honey bees (Apis mellifera) across most regions of the world and is prevalent throughout most states of Australia. 49 Isolates of M. pluton recovered from diseased colonies or honey samples in New South Wales, Queensland, South Australia, Tasmania and Victoria were compared using SDS-PAGE, Western immunoblotting and restriction endonuclease analyses. DNA profiles of all 49 geographically diverse isolates showed remarkably similar AluI profiles although four isolates (one each from Queensland, South Australia, New South Wales and Victoria) displayed minor profile variations compared to AluI patterns of all other isolates. DNA from a subset of the 49 Australian and three isolates from the United Kingdom were digested separately with the restriction endonucleases CfoI, RsaI and DraI. Restriction endonuclease fragment patterns generated using these enzymes were also similar although minor variations were noted. SDS-PAGE of whole cell proteins from 13 of the 49 isolates from different states of Australia, including the four isolates which displayed minor profile variations (AluI) produced indistinguishable patterns. Major immunoreactive proteins of approximate molecular masses of 21, 24, 28, 30, 36, 40, 44, 56, 60, 71, 79 and 95 kDa were observed in immunoblots of whole cell lysates of 22 of the 49 isolates and reacted with rabbit hyperimmune antibodies raised against M. pluton whole cells. Neither SDS-PAGE or immunoblotting was capable of distinguishing differences between geographically diverse isolates of M. pluton. Collectively these data confirm that Australian isolates of M. pluton are genetically homogeneous and that this species may be clonal. Plasmid DNA was not detected in whole cell DNA profiles of any isolate resolved using agarose gel electrophoresis.

Ciudad Mercado, infraestructura en red. Madrid.

OpenAIRE

Carruthers, Luz María

2016-01-01

Los mercados de abastos de Madrid atraviesan uno profunda crisis que conlleva su decadencia arquitectónica. Si bien han sido una pieza el clave en la construcción social y urbana de Madrid. no son considerados una infraestructura, lo cual repercute en el tipo y calidad de intervenciones a los que se los somete. Recuperar su condición infraestructura, supone pensar en los mercados como red, enfocándose en las interacciones que plantean con el entorno a múltiples escalas. Éstas, pueden deber...

Realidad de la prueba de mercado

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Michel Berger

1987-04-01

Full Text Available RESUMEN El artículo presenta una visión esquemática de la controvertida  y olvidada Prueba de Mercado. Esta herramienta  presenta la particularidad de cumplir a la vez funciones de planeación y de control en el proceso de innovación de productos y estrategias de comercialización. Se trata entonces de mostrar que la Prueba de Mercado es una actividad menos compleja de lo que se presume y de acuerdo con la realidad colombiana es muy difícil sustituir.

Distinctly different parental magmas for plutons and lavas in the central Aleutian arc

Science.gov (United States)

Cai, Y.; Rioux, M. E.; Kelemen, P. B.; Goldstein, S. L.; Bolge, L.; Kylander-Clark, A. R.

2014-12-01

While it is generally agreed that continental crust is generated by arc magmatism, average arc lavas are basaltic while the bulk continental crust is andesitic, and this has led to many models for secondary reprocessing of the arc crust in order to form continental crust. We report new data on calc-alkaline plutons in the central Aleutians showing that they have distinctly different sources compared to Holocene tholeiitic lavas. Therefore the lavas are not representative of the net magmatic transfer from the mantle into the arc crust. Eocene to Miocene (9-39 Ma) intermediate to felsic plutonic rocks from the central Aleutian arc show higher SiO2 at a given Mg#, higher ɛNd- and ɛHf-values, and lower Pb isotope ratios than Holocene volcanic rocks from the same region. Instead, the plutonic rocks resemble volcanics from the western Aleutians isotopically, and have chemical compositions similar to bulk continental crust. These data could reflect temporal variation of Aleutian magma source compositions, from Eocene-Miocene "isotopically depleted" and predominantly calc-alkaline to Holocene "isotopically enriched" and predominantly tholeiitic. Alternatively, they may reflect different transport and emplacement processes for the magmas that form plutons and lavas: calc-alkaline magmas with higher Si content and high viscosity may preferentially form plutons, perhaps after extensive mid-crustal degassing of initially high water contents. The latter case implies that the upper and middle arc crust is more like the calc-alkaline bulk composition of the continental crust than the lavas alone. Crustal reprocessing mechanisms that preserve upper and middle arc crust, while removing lower arc crust, can account for the genesis and evolution of continental crust. Since gabbroic lower arc crust extends from ca 20-40 km depth, and is density stable over most of this depth range, "delamination" of dense lithologies [1] may not be sufficient to accomplish this. Alternatively

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

International Nuclear Information System (INIS)

Gallucci, A.R.

1993-01-01

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

The Jeffers Brook diorite-granodiorite pluton: style of emplacement and role of volatiles at various crustal levels in Avalonian appinites, Canadian Appalachians

Science.gov (United States)

Pe-Piper, Georgia; Piper, David J. W.

2018-04-01

Small appinite plutons ca. 610 Ma outcrop in the peri-Gondwanan Avalon terrane of northern Nova Scotia, with different structural levels exposed. Field mapping shows that the Jeffers Brook pluton is a laccolith emplaced along an upper crustal thrust zone, likely in a dilational jog in a regional dextral strike-slip system. The oldest rocks are probably mafic sills, which heated the area facilitating emplacement of intermediate magmas. Cross-cutting relationships show that both mafic and intermediate magmas were supplied throughout the history of pluton emplacement. The modal composition, mineral chemistry, and bulk chemistry of gabbro, diorite, tonalite, granodiorite, and granite have been studied in the main plutonic phases, dykes, and sills, and mafic microgranular enclaves. As with the type appinites in the Scottish Caledonides, the pluton shows evidence of high water content: the dominance of hornblende, locally within pegmatitic texture; vesicles and irregular felsic patches in enclaves; and late aplite dykes. Analyzed mafic microgranular enclaves are geochemically similar to larger diorite bodies in the pluton. Tonalite-granodiorite is distinct from the diorite in trace-element geochemistry and radiogenic isotopes. Elsewhere to the east, similar rocks of the same age form vertically sheeted complexes in major shear zones; hornblende chemistry shows that they were emplaced at a deeper upper crustal level. This implies that little of the observed geochemical variability in the Jeffers Brook pluton was developed within the pluton. The general requirements to form appinites are proposed to be small magma volumes of subduction-related magmas that reach the upper crust because of continual heating by mafic magmas moving through strike-slip fault pathways and trapping of aqueous fluids rather than venting through volcanic activity.

El poder de mercado en industrias minoristas de gas natural vehicular

OpenAIRE

García, John J.; Velásquez, Hermilson; Montenegro, Carlos Mauricio

2014-01-01

La alta concentración del mercado minorista de Gas Natural Vehicular (GNV) en Colombia permite el ejercicio de poder de mercado. El mecanismo de fijación de precio de venta en las Estaciones de Servicio se asemeja al de un modelo teórico oligopolístico tipo Bertrand, en el cual se identifica una empresa líder en el mercado y otras seguidoras, precio-aceptantes. Por medio del índice de Lerner, se encuentra un mark-up de beneficios cercano al 40% que evidencia el ejercicio de poder de mercado. ...

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

International Nuclear Information System (INIS)

Balice, R.G.; Bennett, K.D.; Wright, M.A.

2005-01-01

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

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.

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

Los mercados de abastos y las ciudades turisticas

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Montserrat Crespi Vallbona

2016-01-01

Full Text Available En este artículo se analiza la importancia de los mercados de abastos como espacios turísticos en el planteamiento promocional de la ciudad y sus consecuencias sobre ésta. Los casos de Barcelona y Madrid nos sirven para ilustrar esta realidad. Concretamente, los mercados de La Boquería, Santa Caterina, Barceloneta, La Princesa y Sant Antoni (para Barcelona; San Miguel, San Antón, La Cebada, Barceló, San Fernando, Antón Martín y Los Mostenses (en Madrid. Y en éstos, lo que presenciamos es que los mercados de abastos presentan diversas fisonomías en función del grado de turistificación que puede constatarse en ellos. Así pues, nos planteamos establecer una tipología de mercados, a partir de diferentes variables que determinan la actual evolución de estos espacios desde ser equipamientos y servicios públicos a ser equipamientos propiamente de comercio y consumo, y las consecuencias que reportan para la ciudad cada uno de ellos.

The Precambrian/Lower Cambrian pluton from Vila Nova (Central Portugal)

Energy Technology Data Exchange (ETDEWEB)

Reis, A. I. M.; Silva, M. M. V. G.; Antunes, I. M. H. R.

2010-07-01

The Vila Nova pluton is a small, Pre-Variscan granitic body that intruded rocks of the Central Iberian Zone near the contact with the Ossa Morena Zone and is affected by several shear zones and faults. Its contact metamorphic aureole is constituted by micaschist with porphyroblasts in the outer zone and hornfels in the inner zone. Small mainstreamed xenoliths are dispersed all over the body. The pluton has a great mineralogical heterogeneity with pronounced variations in muscovite/biotite and plagioclase/ microcline contents and is classified as granite, granodiorite or tonalite. It is a leuco granite, highly peraluminous (A/CN K = 1.31 - 1.64), magnesian and calc-alkaline to alkaline-calcic. The variation diagrams show curvilinear trends with silica. Eu/Eu* = 0.47 - 0.77 and there is a slight enrichment in LREE relative to HREE. The normalized diagrams indicated dominantly crustal granite, related to subduction. U-Pb isotopic data of zircon and monazite gives 540-542 Ma age. (Author) 19 refs.

OS MERCADOS PÚBLICOS E A CIDADE: as transformações do Mercado Municipal de Uberlândia (MG

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Lidiane Aparecida Alves

2011-10-01

Full Text Available É consenso a relação das atividades comerciais com a estruturação das cidades. Desde as primeiras cidades o mercado, enquanto forma e função, apresenta papel de destaque nesse processo. Todavia, enquanto palco, e ao mesmo tempo, condicionante para a reprodução das relações sociais, a cidade e seus múltiplos usos apresentam-se em constante transformação de acordo com os anseios da sociedade ao longo de cada período histórico. Sendo que, nos mercados públicos, espaços voltados não só para a comercialização, mas também para a socialização, é possível apreender elementos e produtos típicos de uma dada cidade, região ou país, os quais são cada vez mais valorizados enquanto mercadorias capazes de atrair fluxos e assegurar a permanência dos destes nos dias atuais. Neste sentido, este trabalho tem como objetivo analisar a dinâmica do Mercado Municipal de Uberlândia a fim de compreender o papel do Mercado Municipal ao longo de sua existência. Para tanto fez-se necessário a realização de um levantamento do referencial teórico a cerca da temática em questão, bem como de trabalhos de campo. A partir da concretização desse trabalho tem-se que o Mercado Municipal de Uberlândia assumiu distintas configurações, de acordo com os desígnios dos períodos históricos.

A paleomagnetic and stable isotope study of the pluton at Rio Hondo near Questa, New Mexico: Implications for CRM related to hydrothermal alteration

International Nuclear Information System (INIS)

Hagstrum, J.T.; Johnson, C.M.

1986-01-01

Paleomagnetic and rock magnetic data combined with stable isotope data from the middle Tertiary pluton along the Rio Hondo in northern New Mexico suggest that its magnetic remanence has both thermal (TRM) and high-temperature chemical (CRM) components. Oxygen isotope temperatures indicate that magnetite associated with the more rapidly cooled higher levels of the pluton, and with mafic inclusions and cogenetic rhyolitic dikes sampled at lower levels of exposure, ceased subsolidus recrystallization and isotopic exchange above its Curie temperature (580 0 C) in the presence of a magmatic fluid. Continued cooling imparted a TRM to these portions of the pluton. The more slowly cooled granodiorite at lower levels has quartz-magnetite isotopic temperatures that are below the Curie temperature of magnetite implying that its magnetization is high-temperature CRM. Sub-Curie isotopic temperatures for other granitic plutons in the western U.S.A. suggest that CRM may be commonly derived from subsolidus interactions between magnetite and magmatic fluids in plutonic rocks. A meteoric-hydrothermal system generated by the cooling Rio Hondo pluton, and not by younger adjacent intrusions, resulted in limited alteration along zones of high permeability near the southern margin of the Rio Hondo pluton, and in more prevasive alteration of the pluton to the north. The meteoric-hydrothermal alteration occurred at relatively high temperatures (>350 0 C) and, with the exception of local chloritization, caused little visible alteration of the rocks. The isotopic ratios indicate that little of the magnetite could have grown from or exchanged with a meteoric-hydrothermal fluid. (orig.)

Determination of emplacement mechanism of Zafarghand granitoid Pluton (Southeast of Ardestan by using anisotropy of magnetic susceptibility method (AMS

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Mahmoud Sadeghian

2017-03-01

Full Text Available Zafarghand granitoid pluton with compositional range from gabbro to granite and early to middle Miocene age cropped out about 35 km of SE Ardestan. This pluton intrudedthe Eocene volcanic and volcanosedimentary rocks of the Urumieh - Dokhtar structuralzone. In this research, for the first time, the emplacement mechanism of Zafarghandgranitoidic pluton method has been investigated using of anisotropy of magneticsusceptibility (AMS. Based on field observations, as well as petrography andinterpretations of magnetic parameters, Zafarghand pluton divided into 5 domains (1A,1B, 2, 3, 4 and 5. Domain 1, in turn, is divided into 1A and 1B. Domains 2 and 4 arelithologically, gabbro to quartzdiorite and have been emplaced first. They have playedas feeder zones. Domains 1A, 1B, 3, and 5 are dominantly granodioritic to graniticcomposition and have been emplaced as a big and low dip magmatic flow (or possibly as a sill. The occurrence of gabbro to quartzdiorite as well as grandiorite, granite andtonalite in the margin borders of the body, are all indication of magma mixing. It isshould be noted that during emplacement of the pluton studied, fractionalcrystallization, magma mixing and crustal contamination contributed to its generationand the evolution as well.

Use of olivine and plagioclase saturation surfaces for the petrogenetic modeling of recrystallized basic plutonic systems

Science.gov (United States)

Hanson, G. N.

1983-01-01

During petrogenetic studies of basic plutonic rocks, there are at least three major questions to be considered: (1) what were the relative proportions of cumulate crystals and intercumulus melt in a given sample? (2) what is the composition and variation in composition of the melts within the pluton? and (3) what is the original composition of the liquids, their source and evolution prior to the time of emplacement? Use of both saturation surfaces can place strong limits on the compositions of potential cumulate phases and intercumulus melts. Consideration of appropriate trace elements can indicate whether a sample is an orthocumulate, adcumulate or mesocumulate. Thus, when trace element and petrographic data are considered together with the saturation surfaces, it should be possible to begin to answer the three major questions given above, even for strongly recrystallized basic plutons.

Transformation of juvenile Izu-Bonin-Mariana oceanic arc into mature continental crust: An example from the Neogene Izu collision zone granitoid plutons, Central Japan

Science.gov (United States)

Saito, Satoshi; Tani, Kenichiro

2017-04-01

Granitic rocks (sensulato) are major constituents of upper continental crust. Recent reviews reveal that the average composition of Phanerozoic upper continental crust is granodioritic. Although oceanic arcs are regarded as a site producing continental crust material in an oceanic setting, intermediate to felsic igneous rocks occurring in modern oceanic arcs are dominantly tonalitic to trondhjemitic in composition and have lower incompatible element contents than the average upper continental crust. Therefore, juvenile oceanic arcs require additional processes in order to get transformed into mature continental crust enriched in incompatible elements. Neogene granitoid plutons are widely exposed in the Izu Collision Zone in central Japan, where the northern end of the Izu-Bonin-Mariana (IBM) arc (juvenile oceanic arc) has been colliding with the Honshu arc (mature island arc) since Middle Miocene. The plutons in this area are composed of various types of granitoids ranging from tonalite to trondhjemite, granodiorite, monzogranite and granite. Three main granitoid plutons are distributed in this area: Tanzawa plutonic complex, Kofu granitic complex, and Kaikomagatake granitoid pluton. Tanzawa plutonic complex is dominantly composed of tonalite and trondhjemite and characterized by low concentration of incompatible elements and shows geochemical similarity with modern juvenile oceanic arcs. In contrast, Kofu granitic complex and Kaikomagatake granitoid pluton consists mainly of granodiorite, monzogranite and granite and their incompatible element abundances are comparable to the average upper continental crust. Previous petrogenetic studies on these plutons suggested that (1) the Tanzawa plutonic complex formed by lower crustal anatexis of juvenile basaltic rocks occurring in the IBM arc, (2) the Kofu granitic complex formed by anatexis of 'hybrid lower crust' comprising of both basaltic rocks of the IBM arc and metasedimentary rocks of the Honshu arc, and (3) the

An integrated geological, geochemical, and geophysical investigation of uranium metallogenesis in selected granitic plutons of the Miramichi Anticlinorium, New Brunswick

International Nuclear Information System (INIS)

Hassan, H.H.; McAllister, A.L.

1992-01-01

Integrated geological, geochemical, and geophysical data for the post-tectonic granitic rocks of the North Pole, Burnthill, Dungarvon, Trout Brook, and Rocky Brook plutons and surrounding areas were examined to assess their potential for uranium mineralization. Geological, geochemical, and geophysical criteria that are thought to be useful guides for uranium exploration were also established for the host granites. The granitic plutons were emplaced discordantly, late in the tectonomagmatic sequence and at shallow depths within the metasedimentary rocks of the Miramichi Anticlinorium. Geochemically, the host granites are highly evolved (Si0 2 > 75 wt. %), peraluminous and have strong similarities with ilmenite-series 'S-type' and 'A-type' granitoids. Uranium occurrences are spatially and perhaps temporally associated with late-phase differentiates of the plutons where elevated levels of other lithophile elements such as Sn, W, Mo, and F were also detected. Geophysically, the granitic plutons are associated with distinctively high aeroradiometric eU, eTh, and K anomalies that coincide with strong negative Bouguer anomalies and low magnetic values. Conceptual models involving magmatic and hydrothermal processes have been adopted to explain the concentration of uranium and associated metals in the granitic plutons

EDUCACION, MERCADO Y CIUDADANIA

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Juan Carlos Tedesco

1998-01-01

Full Text Available El criterio referencial, presente a lo largo del texto, es la imposibilidad e inconveniencia de dar respuestas categóricas y únicas a los complejos problemas educativos contemporáneos. Desde esta postura, el autor aborda tres temas educativos, permeados por la relación mercado, equidad y ciudadanía; son expuestos por separado pero están articulados: la toma de decisiones para asignar recursos y cuotas de acceso a la educación y el debate entre concertación y mercado; la equidad educativa, lo que lleva a realzar el debate sobre el papel de la acción estatal y la privada; los contenidos que en la actualidad han de caracterizar a los procesos educativos, lo que remite a considerar divergencias y cercanías entre formación ciudadana y formación para la competitividad.

Death Valley turtlebacks: Mesozoic contractional structures overprinted by Cenozoic extension and metamorphism beneath syn-extensional plutons

Energy Technology Data Exchange (ETDEWEB)

Pavlis, T L; Serpa, L [Department of Geological Sciences, University of Texas at El Paso, El Paso, TX 7996 (United States); Miller, M [Department of Geological Sciences, University of Oregon, Eugene, OR 97403 (United States)], E-mail: tlpavlis@utep.edu

2008-07-01

The term turtleback was first coined to describe the curvilinear fault surfaces that produced a distinctive geomorphic form in the Black Mountains east of Death Valley, and although it was decades before their full significance was appreciated, they remain one of the most distinctive features of the extensional structure of the Death Valley region. Historically the interpretation of the features has varied markedly, and misconceptions about their character continue to abound, including descriptions in popular field guides for the area. It the 1990's, however, the full history of the systems began to be apparent from several key data: 1) the dating of the plutonic assemblage associated with the turtlebacks demonstrated that late Miocene, syn-extensional plutonism was fundamental to their formation; 2) the plutonic assemblage forms an intrusive sheet structurally above the turtlebacks, indicating a tie between much of the high grade metamorphism and Cenozoic plutonism; 3) a modern analog for the syn-extensional plutonism in the Black Mountains was recognized beneath Death Valley with the imaging of a mid-crustal magma body; 4) the Neogene structural history was worked out in the turtlebacks showing that folding of early-formed shear zones formed the turtleback anticlinoria but overprinting by brittle faults produced the final form as they cut obliquely across the older structure; and 5) the pre-extensional structural history was clarified, demonstrating that Mesozoic basement-involved thrust systems are present within the turtlebacks, but have been overprinted by the extensional system. An unresolved issue is the significance of Eocene U-Pb dates for pegmatites within the region, but presumably these relate somehow to the pre-extensional history. Miller and Pavlis (2005; E. Sci. Rev.) reviewed many features of the turtlebacks, and our working model for the region is that the turtlebacks originated as mid-crustal ductile-thrust systems within the Cordilleran fold

Death Valley turtlebacks: Mesozoic contractional structures overprinted by Cenozoic extension and metamorphism beneath syn-extensional plutons

International Nuclear Information System (INIS)

Pavlis, T L; Serpa, L; Miller, M

2008-01-01

The term turtleback was first coined to describe the curvilinear fault surfaces that produced a distinctive geomorphic form in the Black Mountains east of Death Valley, and although it was decades before their full significance was appreciated, they remain one of the most distinctive features of the extensional structure of the Death Valley region. Historically the interpretation of the features has varied markedly, and misconceptions about their character continue to abound, including descriptions in popular field guides for the area. It the 1990's, however, the full history of the systems began to be apparent from several key data: 1) the dating of the plutonic assemblage associated with the turtlebacks demonstrated that late Miocene, syn-extensional plutonism was fundamental to their formation; 2) the plutonic assemblage forms an intrusive sheet structurally above the turtlebacks, indicating a tie between much of the high grade metamorphism and Cenozoic plutonism; 3) a modern analog for the syn-extensional plutonism in the Black Mountains was recognized beneath Death Valley with the imaging of a mid-crustal magma body; 4) the Neogene structural history was worked out in the turtlebacks showing that folding of early-formed shear zones formed the turtleback anticlinoria but overprinting by brittle faults produced the final form as they cut obliquely across the older structure; and 5) the pre-extensional structural history was clarified, demonstrating that Mesozoic basement-involved thrust systems are present within the turtlebacks, but have been overprinted by the extensional system. An unresolved issue is the significance of Eocene U-Pb dates for pegmatites within the region, but presumably these relate somehow to the pre-extensional history. Miller and Pavlis (2005; E. Sci. Rev.) reviewed many features of the turtlebacks, and our working model for the region is that the turtlebacks originated as mid-crustal ductile-thrust systems within the Cordilleran fold

Soberania Alimentar, agroecologia e mercados locais.

OpenAIRE

Meirelles, Laércio

2004-01-01

A Rede Ecovida tem estimulado a construção de uma Rede Solidária de Produção e Circulação de Produtos Ecológicos nos estados do Paraná, de Santa Catarina e do Rio Grande do Sul, cujas células de comercialização são feiras livres, cooperativas de consumidores, mercados institucionais, pontos de abastecimento popular, pequenas lojas e comerciantes. Essa iniciativa é mais uma demonstração que práticas agroecológicas, associadas a mercados locais, trazem impactos positivos à Soberania Alimentar d...

Estrategias de mercado para el frijol centroamericano

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Lourdes Mart\\u00EDnez

2004-01-01

Full Text Available Estrategias de mercado para el frijol centroamericano. En los últimos años, el sub-sector de frijol en Centro América ha sido testigo de varios cambios dinámicos. Si no se encuentran medidas para incrementar la competitividad regional de este sub-sector, los países centroamericanos experimentarán impactos negativos en las áreas sociales y económicas de considerable magnitud, especialmente ahora que Centro América necesita ajustar su economía a los nuevos requerimientos de mercados mas abiertos, como el Tratado Centroamericano de Libre Comercio con USA (TLC. Vendedores de frijoles a nivel intermediario y de consumo final, así como técnicos de oficinas gubernamentales dedicadas al mercadeo de frijoles en Centro América fueron entrevistados para documentar los cambios experimentados, identificar los obstáculos que frenan la viabilidad del sub-sector e identificar las oportunidades de incremento de mercados en el futuro para los productores y vendedores de frijol. Los resultados muestran que para que continúen siendo competitivos, los países centroamericanos deben incrementar la productividad a través del apoyo a las investigaciones para el mejoramiento de variedades de frijol, especialmente aquellas que los consumidores prefieren por características específicas (e.g. color. También es imprescindible el fortalecimiento de los programas de distribución de variedades mejoradas a los productores; las mejoras en la transmisión de información de mercado a los productores; el fortalecimiento de los contactos entre productores, comercializadores a nivel mayorista y supermercados; y una política más específica de apertura de mercados de exportación, especialmente con los Estados Unidos.

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

Energy Technology Data Exchange (ETDEWEB)

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

1983-12-15

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

The rapakivi granite plutons of Bodom and Obbnäs, southern Finland: petrography and geochemistry

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Kosunen, P.

1999-12-01

Full Text Available The Obbnäs and Bodom granite plutons of southernmost Finland show the typical petrographic and geochemical features of the Proterozoic rapakivi granites in Finland and elsewhere: they cut sharply across the 1900 Ma Svecofennian metamorphic bedrock and have the geochemical characteristics of subalkaline A-type granites. The Bodom pluton is composed of porphyritic granites (hornblende-, hornblende-biotite-, and biotite-bearing varieties and an even-grained granite that probably represent two separate intrusive phases. This lithologic variation does not occur in the Obbnäs pluton, which is almost entirely composed of porphyritic hornblende-biotite granite that gradually becomes more mafic to the southwest. Three types of hybrid granitoids resulting from magma mingling and mixing occur on the southwestern tip of the Obbnäs peninsula. The Bodom granites are syenogranites, whereas the composition of the Obbnäs granite varies from syeno- to monzogranite. The main silicates of both the Bodom and Obbnäs granites are quartz, microcline, plagioclase (An1541, biotite (siderophyllite, and generally also amphibole (ferropargasite or hastingsite. Plagioclase-mantled alkali feldspar megacrysts are absent or rare. The accessory minerals are fluorite, allanite, zircon, apatite, and iron-titanium oxides; the Obbnäs granite also contains titanite. The Bodom and Obbnäs granites are metaluminous to weakly peraluminous, with average A/CNK of 1.00 and 1.05, respectively, have high Fe/Mg (average FeOtot/[FeOtot+MgO] is 0.94 for the Bodom and 0.87 for the Obbnäs granites, and high Ga/Al (3.78 to 5.22 in Bodom and 2.46 to 4.18 in Obbnäs. The REE contents are high with LREE-enriched chondrite-normalized patterns and moderate (Obbnäs to relatively strong (Bodom negative Eu-anomalies. The Obbnäs granite is enriched in CaO, TiO2, MgO, and FeO, and depleted in SiO2 and K2O compared to the Bodom granites. Also, there are differences in the Ba, Rb, and Sr contents of

Petrological studies of plutonic rocks of Ecuador

International Nuclear Information System (INIS)

Aly, S.

1980-01-01

The feldspars of many tonalitic plutonic rocks in the coastal regions and West Andean regions are zoned. This leads to the conclusion that they are relatively flat intrusions and to some extent transition rocks in the subvulcanite direction. This is in accordance with the genetic and chronological relationship between plutonites and the surrounding vulcanites of the Basic Igreous Complex (BIC). The composition of representative minerals, e.g. alkali feldspar, plagioclase feldspar, biotite, chlorite, and amphibole has been determined as well as the age of plutonite samples by the K/Ar dating method. (DG) [de

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.

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.

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)

1992-12-31

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.

La administración del riesgo en el Mercado Forex

OpenAIRE

López Suárez, Santiago

2014-01-01

Los inversionistas, desde el ángulo especulativo y con enfoque en el análisis técnico abordan los mercados financieros con estrategias que involucran mucho su percepción propia -- Los avances tecnológicos no solo facilitan el tener una cercanía constante a los mercados financieros a través de plataformas o software descargables, sino facilidad de acceso a diversas estrategias técnicas vigentes aplicadas a estos mercados, pero lo que diferencia el éxito del fracaso al especular con activos fin...

Site investigation methods used in Canada's nuclear fuel waste management program to determine the hydrogeological conditions of plutonic rock

International Nuclear Information System (INIS)

Davison, C.C.

1985-01-01

Atomic Energy of Canada Limited (AECL) is investigating the concept of disposing of Canada's nuclear fuel wastes in a mined vault at a depth of 500 m to 1000 m within a plutonic rock body. Much effort has been directed at developing site investigation methods that can be used to determine the hydrogeological conditions of plutonic rock bodies. The primary objective of this research is to define the physical and chemical characteristics of groundwater flow systems at the various scales that are relevant to the prediction of potential radionuclide migration from a disposal vault. Groundwater movement through plutonic rock is largely controlled by fractures within the rock, and the hydrogeological parameters of fractured geological media are extremely scale dependent

O Mercado Único Digital Europeu

Directory of Open Access Journals (Sweden)

Fernanda Ferreira Dias

2016-11-01

Full Text Available A Internet e as tecnologias digitais estão a transformar o nosso mundo a todos os níveis e invadem todos os aspetos da nossa vida. Na União Europeia, quando o Mercado Único Digital funcionar em pleno, oferecerá novas oportunidades para dinamizar a economia; é atualmente uma das áreas mais importantes e que mais desafios apresenta em termos de progresso e crescimento. O Mercado Único Digital Europeu exige um quadro jurídico que permita o desenvolvimento dos vários aspetos que abrange, e que vão desde o comércio eletrónico, à administração pública em linha, infraestruturas de telecomunicações, fiscalidade, direitos de autor, conectividade dos dados, segurança ou privacidade dos dados pessoais. A “Estratégia para o Mercado Único Digital na Europa” enquadra esta ação. O Mercado Único Digital está em curso e tem por objetivo eliminar as barreiras regulamentares existentes nos mercados nacionais dos 28 Estados-membros da União Europeia para um único mercado europeu. Este artigo revela os passos que a União Europeia e os seus Estados-membros estão a dar para a concretização deste objetivo e tem obviamente o enfoque na participação de Portugal nesse contexto, no ano em que se realiza em Lisboa, pela primeira vez, a Web Summit – o maior evento de empreendedorismo tecnológico ao nível europeu. | "The European Digital Single Market". The Internet and digital technologies are transforming our world at all levels and invade all aspects of our lives. When the European Digital Single Market will be fully operational, it will offer new opportunities to boost the European Union’s economy; it is currently one of the most important and challenging areas in terms of progress and growth. The European Digital Single Market requires a legal framework for the development of various aspects ranging from e-commerce to e-government, telecommunications infrastructure, taxation, copyright, data connectivity, security or privacy of

A HIPÓTESE CONJUNTA DO CAPM E MERCADO EFICIENTE

Directory of Open Access Journals (Sweden)

César Martins Guimarães

2006-05-01

Full Text Available O CAPM é utilizado para testar a eficiência de mercados desde o final dos anos 1960. O objetivo deste trabalho foi testar a hipótese conjunta do CAPM e da eficiência do mercado brasileiro de ações nos cinco anos compreendidos entre abril de 2000 e março de 2005, através da análise do desempenho de fundos mútuos de ações. O Alfa de Jensen foi escolhido como medida de retorno extraordinário dos fundos de ações, por considerar o ajuste do resultado em relação � exposição da carteira ao risco sistemático. Os dados apontaram que não há evidências de ineficiência de mercado para o período analisado, assumindo-se ser o IBX e o Ibovespa índices representativos da carteira de mercado e o CDI de um dia uma taxa representativa do ativo livre de risco.

Flexibilidade e mercado de trabalho em Portugal

OpenAIRE

Centeno, Mário; Novo, Álvaro

2008-01-01

A era de rápida evolução tecnológica em que vivemos, associada em particular ao desenvolvimento de tecnologias de informação, coloca às economias novos desafios, mas também novas oportunidades, abrindo à concorrência mercados anteriormente fechados. Neste ambiente mais competitivo, não é estranho que o apelo a uma maior flexibilidade do emprego tenha ganho proeminência na discussão político-económica da organização do mercado de trabalho.

México en el mercado internacional de aguacate

Directory of Open Access Journals (Sweden)

Alejandro Macías Macías

2011-01-01

Full Text Available El mercado internacional de aguacate ha sufrido importantes modificaciones durante las dos últimas décadas. Por un lado, aunque se trata de una fruta exótica, cada vez es más consumida en el mundo Por otro, surgen nuevas potencias exportadoras que desplazan a anteriores naciones líderes: México, principal productor y consumidor de la fruta, es, a partir de la década de 1990, en el máximo exportador, como resultado de la apertura del mercado de los Estados Unidos. Al mismo tiempo, países sudamericanos como Chile y Perú, cada vez tienen mayor presencia en el mercado europeo, desplazando relativamente a Israel, Sudáfrica, España, Kenia o Ecuador. Finalmente, se emergen nuevos vendedores como Australia o se reafirman otros como República Dominicana.

Integración de los Mercados Accionarios de Chile, Colombia y Perú en el Mercado Integrado Latinoamericano (MILA)

OpenAIRE

Eduardo Sandoval Alamos; Arturo Z. Vásquez-Párraga; Rocío Sabat Arriagada

2015-01-01

El objetivo de este artículo es evaluar y comparar el grado de integración de los mercados accionarios de Chile, Colombia y Perú, antes y después de la implementación del Mercado Integrado Latinoamericano (MILA). Para este fin se utiliza una versión condicional del CAPM internacional que asume PRSM (precios por riesgo sistemático mundial) constantes versus dos especificaciones alternativas. La primera especificación extiende el modelo base al incorporar variables de segmentación junto al r...

PLUTON, Isotope Generation and Depletion in Highly Irradiated LWR Fuel Rods

International Nuclear Information System (INIS)

Lemehov, Sergei; Motoe, Suzuki

2003-01-01

1 - Description of program or function: The PLUTON-PC is a three-group neutronic code analyzing, as functions of time and burnup, the change of radial profiles, together with average values, of power density, burnup, concentration of trans-uranium elements, plutonium buildup, depletion of fissile elements, and fission product generation in water reactor fuel rod with standard UO 2 , UO 2 -Gd 2 O 3 , inhomogeneous MOX, and UO 2 -ThO 2 . The PLUTON-PC code, which has been designed to be run on Windows PC, has adopted a theoretical shape function of neutron attenuation in pellet, which enables users to perform a very fast and accurate calculation easily. The code includes the irradiation conditions of the Halden Reactor which gives verification data for the code. Verification has been performed up to 83 GWd/tU, and a satisfactory agreement has been obtained. 2 - Methods: Based upon cumulative yields, the PLUTON-PC code calculates as a function of radial position and local burnup concentrations of fission products, macroscopic scattering cross-sections and self-shielding effect which is important for standard fuel (for Pu-242 mainly) and more importantly for homogeneous and inhomogeneous MOX fuel because of higher concentrations of fissile and fertile isotopes of plutonium. The code results in burnup dependent fission rate density profiles throughout the in-reactor irradiation of LWR fuel rods. The isotopes included in calculations have been extended to cover all trans-uranium groups (plutonium plus higher actinides) of fissile and fertile isotopes. Self-shielding problem and scattering effects have been revised and solved for all isotopes in the calculations for adequacy at high burnup, different irradiation conditions and cladding materials

Geology, geochemistry, age and tectonic setting of the Gore-Gambella plutonic rocks, western Ethiopia

Energy Technology Data Exchange (ETDEWEB)

Alemayehu, T.A.

1989-01-01

In transect across the Birbir and Baro domains of western Ethiopia, distinct granitoid suites are recognized on the basis of their field relations, petrology, chemical features and age. The Baro Domain consists of migmatitic, upper amphibolite facies gneisses and metaleucogranites. The Birbir Domain consists of lower amphibolite facies rocks with abundant intrusive and meta-intrusive rocks of mafic and intermediate composition. A ductile, transcurrent fault system, the Birbir Shear Zone, traverses the Birbir Domain. Kinematic indicators such as disrupted dykes and sills within the shear zone suggest major dextral movement which was succeeded by sinistral movement during its final stage. The pre- to syn-kinematic intrusives within the Birbir Domain are metamorphosed and mylonitized to variable degrees. Geochemical and isotopic data from early plutonic units in the Birbir Domain reflect arc-type igneous activity; late- to post-kinematic plutons are more alkalic and of intraplate character. U-Pb zircon and Rb-Sr whole-rock isochron dates show plutonic activity between 830 and 540 Ma. A whole-rock Rb-Sr date of 760 Ma from a pre- to syn-kinematic pluton coincides with the age of low-grade metamorphism of arc-related rocks of the Red Sea Hills of NE Africa and the Jeddah terrane of Arabia. The Birbir Domain is a southward extension of the Pan-African crust of NE Africa and Arabia. The Birbir shear zone indicates a tectonically active continental margin along which magmatic arc rocks were accreted. The Baro Domain is interpreted as a reactivated pre-Pan-African continental margin linked to the Mozambique Belt of east Africa. A subduction model, involving closure of an ocean basin, is proposed for the evolution of rocks of the Birbir Domain.

La Escalerilla pluton, San Luis Argentina: The orogenic and post-orogenic magmatic evolution of the famatinian cycle at Sierras de San Luis

Science.gov (United States)

Morosini, Augusto Francisco; Ortiz Suárez, Ariel Emilio; Otamendi, Juan Enrique; Pagano, Diego Sebastián; Ramos, Gabriel Alejandro

2017-01-01

Field relationships, geochemical analysis and two new absolute ages (LA-MC-ICP-MS U/Pb-zircon) allow the division of the La Escalerilla pluton (previously considered to be a single granitic body) into two different plutons: a new La Escalerilla pluton (s.s.), dated at 476.7 ± 9.6 Ma, that represents the northern portion, and the El Volcán pluton, dated at 404.5 ± 8.5 Ma, located in the southern sector. The La Escalerilla pluton is composed of three facies: (1) biotite-bearing granodiorite, (2) porphyritic biotite-bearing granite, and (3) porphyritic two micas-bearing leucogranite, being the presence of late-magmatic dykes in these facies common. The El Volcán pluton is composed of two main facies: 1) porphyritic biotite-bearing granite, and 2) two micas-bearing leucogranite, but amphibole-bearing monzodioritic and tonalititic mega-enclaves are also common, as well as some dykes of amphibole and clinopyroxene-bearing syenites. A peculiarity between the two plutons is that their most representative facies (porphyritic biotite-bearing granites) have, apart from different absolute ages, distinctive geochemical characteristics in their concentrations of trace elements; the La Escalerilla granite is comparatively poorer in Ba, Sr, Nb, La, Ce, P, and richer in Rb, Tb, Y, Tm and Yb. The El Volcán granite is notably enriched in Sr and depleted in Y, resulting in high Sr/Y ratios (12.67-39.08) compared to the La Escalerilla granite (1.11-2.41). These contrasts indicate that the separation from their sources occurred at different depths: below 25 km for the La Escalerilla, and above 30 km for the El Volcán. Moreover, the contrasts allow us to interpret a thin crust linked to an environment of pre-collisional subduction for the first case, and a thickened crust of post-collisional environment for the second, respectively.

Transpressional granite-emplacement model: Structural and magnetic study of the Pan-African Bandja granitic pluton (West Cameroon)

Science.gov (United States)

Sandjo, A. F. Yakeu; Njanko, T.; Njonfang, E.; Errami, E.; Rochette, P.; Fozing, E.

2016-02-01

The Pan-African NE-SW elongated Bandja granitic pluton, located at the western part of the Pan-African belt in Cameroon, is a K-feldspar megacryst granite. It is emplaced in banded gneiss and its NW border underwent mylonitization. The magmatic foliation shows NE-SW and NNE-SSW strike directions with moderate to strong dip respectively in its northern and central parts. This mostly, ferromagnetic granite displays magnetic fabrics carried by magnetite and characterized by (i) magnetic foliation with best poles at 295/34, 283/33 and 35/59 respectively in its northern, central and southern parts and (ii) a subhorizontal magnetic lineation with best line at 37/8, 191/9 and 267/22 respectively in the northern, central and southern parts. Magnetic lineation shows an `S' shape trend that allows to (1) consider the complete emplacement and deformation of the pluton during the Pan-African D 2 and D 3 events which occurred in the Pan-African belt in Cameroon and (2) reorganize Pan-African ages from Nguiessi Tchakam et al. (1997) compared with those of the other granitic plutons in the belt as: 686 ±17 Ma (Rb/Sr) for D 1 age of metamorphism recorded in gneiss; and the period between 604-557 Ma for D 2-D 3 emplacement and deformation age of the granitic pluton in a dextral ENE-WSW shear movement.

Plutonic rocks in the Mineoka-Setogawa ophiolitic mélange, central Japan: Fragments of middle to lower crust of the Izu-Bonin-Mariana Arc?

Science.gov (United States)

Ichiyama, Yuji; Ito, Hisatoshi; Hokanishi, Natsumi; Tamura, Akihiro; Arai, Shoji

2017-06-01

A Paleogene accretionary complex, the Mineoka-Setogawa Belt, is distributed around the Izu Collision Zone, central Japan. Plutonic rocks of gabbro, diorite and tonalite compositions are included as fragments and dykes in an ophiolitic mélange in this belt. Zircon U-Pb dating of the plutonic rocks indicates that they were formed at ca. 35 Ma simultaneously. These ages are consistent with Eocene-Oligocene tholeiite and calc-alkaline arc magmatism in the Izu-Bonin-Mariana (IBM) Arc and exclude several previous models for the origin of the Mineoka-Setogawa ophiolitic rocks. The geochemical characteristics of these plutonic rocks are similar to those of the Eocene-Oligocene IBM tholeiite and calc-alkaline volcanic rocks as well as to the accreted middle crust of the IBM Arc, the Tanzawa Plutonic Complex. Moreover, their lithology is consistent with those of the middle and lower crust of the IBM Arc estimated from the seismic velocity structure. These lines of evidence strongly indicate that the plutonic rocks in the Mineoka-Setogawa ophiolitic mélange are fragments of the middle to lower crust of the IBM Arc. Additionally, the presence of the Mineoka-Setogawa intermediate to felsic plutonic rocks supports the hypothesis that intermediate magma can form continental crust in intra-oceanic arcs.

Bedrock geologic map of the Knox Mountain pluton area, Marshfield and Peacham, Vermont

Data.gov (United States)

Vermont Center for Geographic Information — Digital Data from VG08-3 Kim, J., Charnock, R., Chow, D. and Springston, G., 2008, Bedrock geologic map of the Knox Mountain pluton area, Marshfield and Peacham,...

Evidence for a close phylogenetic relationship between Melissococcus pluton, the causative agent of European foulbrood disease, and the genus Enterococcus.

Science.gov (United States)

Cai, J; Collins, M D

1994-04-01

The 16S rRNA gene sequence of Melissococcus pluton, the causative agent of European foulbrood disease, was determined in order to investigate the phylogenetic relationships between this organism and other low-G + C-content gram-positive bacteria. A comparative sequence analysis revealed that M. pluton is a close phylogenetic relative of the genus Enterococcus.

La transformación de los mercados municipales de Madrid. Análisis legislativo, comercial, y económico de los mercados de abastos madrileños

Directory of Open Access Journals (Sweden)

Alejandro Rodríguez Sebastián

2015-01-01

Full Text Available ResumenDurante la última década, el Ayuntamiento de Madrid ha desarrollado diferentes políticas con el objetivo de revitalizar los mercados de abastos de la ciudad. Una de ellas ha sido la inserción de cadenas de supermercados junto a las estructuras comerciales tradicionales de los mercados, actuando a modo de "locomotoras’ económicas. Por otro lado, es reconocible la aparición en ciertos mercados de nuevos patrones de consumo, unos asociados a estilos de vida propios de élites y otros surgidos a raíz de las modificaciones realizadas en los mercados. Este trabajo pretende analizar las causas y consecuencias de las diversas transformaciones llevadas a cabo en la red de mercados municipales de Madrid, diferenciando las pautas seguidas en los mercados del centro de la ciudad de los de la periferia.Palabras clave  Mercados municipales, comercio, Madrid, centralidad, periferia, gentrificación comercialAbstractDuring the last decade, Madrid City Council has developed different policies aimed at revitalising the traditional retail markets in the city. One of these has been the insertion of supermarkets next to the traditional commercial structures, acting as economic driving forces. Furthermore, the appearance of new consumption patterns is a remarkable fact, some related to wealthy lifestyles, others arisen due to the changes made in the markets. The aim of this paper is to analyse the causes and consequences of the transformations held in Madrid market network, distinguishing the guidelines followed both in the city centre and in the outskirts.KeywordsTraditional retail markets, trade, Madrid, centrality, suburbs, commercial gentrification

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

Energy Technology Data Exchange (ETDEWEB)

None

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{degrees} 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).

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).

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

A HIPÃTESE CONJUNTA DO CAPM E MERCADO EFICIENTE

Directory of Open Access Journals (Sweden)

César Martins Guimarães

2006-05-01

Full Text Available O CAPM é utilizado para testar a eficiência de mercados desde o final dos anos 1960. O objetivo deste trabalho foi testar a hipótese conjunta do CAPM e da eficiência do mercado brasileiro de ações nos cinco anos compreendidos entre abril de 2000 e março de 2005, através da análise do desempenho de fundos mútuos de ações. O Alfa de Jensen foi escolhido como medida de retorno extraordinário dos fundos de ações, por considerar o ajuste do resultado em relação exposição da carteira ao risco sistemático. Os dados apontaram que não há evidências de ineficiência de mercado para o período analisado, assumindo-se ser o IBX e o Ibovespa índices representativos da carteira de mercado e o CDI de um dia uma taxa representativa do ativo livre de risco.

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.

La Orientación emprendedora y de mercado en la empresa social vs la de mercado: un estudio de caso

OpenAIRE

Rodríguez Moreno, Ramón Enrique

2016-01-01

El presente trabajo de investigación llevará a cabo una identificación y delimitación de los aspectos fundamentales de las orientaciones emprendedora y de mercado, así como una caracterización y una diferenciación de las empresas de economía social y de mercado. El objetivo es analizar las posibles diferencias de ambos tipos de orientaciones en función del tipo de empresa. Para ello, se ha realizado dos estudios de caso, uno para cada tipo de empresa. , las conclusiones obtenidas indican un a...

An evolving tectonic environment of Late Carboniferous to Early Permian granitic plutons in the Chinese Altai and Eastern Junggar terranes, Central Asian Orogenic Belt, NW China

Science.gov (United States)

Zhang, Chen; Liu, Dongdong; Luo, Qun; Liu, Luofu; Zhang, Yunzhao; Zhu, Deyu; Wang, Pengfei; Dai, Quanqi

2018-06-01

The Central Asian Orogenic Belt (CAOB) represents one of the most important sites of juvenile crustal growth during the Phanerozoic. Located in the central part of the CAOB, the Chinese Altai and Eastern Junggar terranes record the collisional processes between the peri-Siberian and Kazakhstan orogenic systems. However, the precise timing of collision between the two terranes remains controversial. The Wukuli and Kadelat plutons in the Chinese Altai belt are dated at ∼305 and ∼280 Ma respectively, whereas the Aketas pluton in the Eastern Junggar terrane is dated at ∼308 Ma. Granites from the Wukuli and Kadelat plutons are strongly peraluminous (A/CNK > 1.1), and are characterized by low Al2O3, Na2O, MnO, MgO, CaO and heavy rare earth element (HREE) contents, but with high SiO2, K2O and Rb contents as well as high Rb/Sr ratios. Granites from the Wukuli pluton have low εNd(t) and εHf(t) values of -3.7 to -3.4 and -9.7 to +4.9, whereas those from the Kadelat pluton have values of -3.6 to -3.4 and -8.0 to +2.6. These features suggest S-type affinity for the Wukuli and Kadelat plutons with magma derivation through partial melting of Mesoproterozoic metasediments. The Aketas pluton is composed of weakly peraluminous quartz monzonites that have A/CNK values ranging from 0.92 to 1.08, with high Na2O, Sr, and Sr/Y, and low Y, Yb, Nb, and Ta. These rocks display positive εNd(t) (+4.8 to +6.4) and εHf(t) (+9.7 to +14.6) values, and low initial 87Sr/86Sr ratios (0.703357-0.703868), similar to modern adakites, suggesting that the quartz monzonites were derived from the partial melting of lower crustal material. The geochemical characteristics suggest that the Aketas pluton was formed in a subduction-related setting, the Wukuli pluton in a syn-collisional setting, and the Kadelat pluton in the subsequent post-orogenic strike-slip-related setting. In combination with data from other granitoids in these two terranes, the Aketas pluton represents the youngest record of

Estrutura de capital e janelas de oportunidade: testes no mercado brasileiro

Directory of Open Access Journals (Sweden)

Eduardo Alexandre Mendes

2009-12-01

Full Text Available Este estudo testa a teoria das janelas de oportunidade (EMTT para o mercado acionário brasileiro. Este texto é uma adaptação do artigo de Baker e Wurgler (2002 que testaram com sucesso essa teoria para o mercado acionário americano. A teoria não foi comprovada no mercado brasileiro. A alavancagem diminuiu no primeiro ano após as ofertas públicas iniciais (IPO, mas cresceu novamente sem apresentar a persistência necessária para corroborar a teoria.

Impact of Santiago de Chile urban atmospheric pollution on anthropogenic trace elements enrichment in snow precipitation at Cerro Colorado, Central Andes

Science.gov (United States)

Cereceda-Balic, F.; Palomo-Marín, M. R.; Bernalte, E.; Vidal, V.; Christie, J.; Fadic, X.; Guevara, J. L.; Miro, C.; Pinilla Gil, E.

2012-02-01

Seasonal snow precipitation in the Andes mountain range is evaluated as an environmental indicator of the composition of atmospheric emissions in Santiago de Chile metropolitan area, by measuring a set of representative trace elements in snow samples by ICP-MS. Three late winter sampling campaigns (2003, 2008 and 2009) were conducted in three sampling areas around Cerro Colorado, a Central Andes mountain range sector NE of Santiago (36 km). Nevados de Chillán, a sector in The Andes located about 500 km south from the metropolitan area, was selected as a reference area. The experimental results at Cerro Colorado and Nevados de Chillán were compared with previously published data of fresh snow from remote and urban background sites. High snow concentrations of a range of anthropogenic marker elements were found at Cerro Colorado, probably derived from Santiago urban aerosol transport and deposition combined with the effect of mining and smelting activities in the area, whereas Nevados de Chillán levels roughly correspond to urban background areas. Enhanced concentrations in surface snow respect to deeper samples are discussed. Significant differences found between the 2003, 2008 and 2009 anthropogenic source markers profiles at Cerro Colorado sampling points were correlated with changes in emission sources at the city. The preliminary results obtained in this study, the first of this kind in the southern hemisphere, show promising use of snow precipitation in the Central Andes as a suitable matrix for receptor model studies aimed at identifying and quantifying pollution sources in Santiago de Chile.

El proceso de integración de los mercados financieros en Europa

Directory of Open Access Journals (Sweden)

Ignacio López Domínguez

2013-07-01

Full Text Available En este artículo se estudia el proceso y la situación en la que se encuentra la integración de los mercados financieros en el ámbito europeo. Para ello, se repasa brevemente la situación de los mercados financieros españoles para, posteriormente, analizar la conveniencia de unificar los distintos mercados financieros europeos, así como sus repercusiones en una futura bolsa europea.

La transformación de los mercados municipales de Madrid. Análisis legislativo, comercial, y económico de los mercados de abastos madrileños

OpenAIRE

Rodríguez Sebastián, Alejandro

2014-01-01

ResumenDurante la última década, el Ayuntamiento de Madrid ha desarrollado diferentes políticas con el objetivo de revitalizar los mercados de abastos de la ciudad. Una de ellas ha sido la inserción de cadenas de supermercados junto a las estructuras comerciales tradicionales de los mercados, actuando a modo de "locomotoras’ económicas. Por otro lado, es reconocible la aparición en ciertos mercados de nuevos patrones de consumo, unos asociados a estilos de vida propios de élites y otros surgi...

A review on the nomenclature of Angadimogar and Kumbdaje plutons, Kasaragod district, Kerala

Digital Repository Service at National Institute of Oceanography (India)

AnilKumar, A.; Gopinathan, V.; Gopinath, K.S.; Rao, V.P.

These granites are coarse grained and traversed by anastomising patches of aplite They are in sharp contact with the country rock The Angadimogar pluton was earlier considered a syenitic body Normative mineralogy and petrography of the Angadimogar and Kumbdaje...

PLUTON: A Three-Group Model for the Radial Distribution of Plutonium, Burnup, and Power Profiles in Highly Irradiated LWR Fuel Rods

International Nuclear Information System (INIS)

Lemehov, Sergei; Nakamura, Jinichi; Suzuki, Motoe

2001-01-01

A three-group model (PLUTON) is described, which predicts the power density distribution, plutonium buildup, and burnup profiles across the fuel pellet radius as a function of in-pile time and parameters characterizing the type of reactor system with respect to fuel temperature and changes of density during the irradiation period. The PLUTON model is a part of two fuel performance codes (ASFAD and FEMAXI-V), which provide all necessary input for this model, mainly local temperatures and fuel matrix density across the radius. Comparisons between measurements and predictions of the PLUTON model are made on fuels with enrichments in the range 2.9 to 8.25% and with burnup between 21 000 and 64 000 MWd/t. It is shown that the PLUTON predictions are in good agreement with measurements as well as with predictions of the well-known TUBRNP model. The proposed model is flexibly applicable for all types of light water reactor (LWR) fuels, including mixed oxide, and for fuel tested in the Organization for Economic Corporation and Development's Halden heavy water reactor. The PLUTON three-group model is based on analytical (theoretical) consideration of neutron absorption in a resonant region of the fuel in its apparent form. It makes the model more flexible in comparison with the semi-empirical TUBRNP one-group model and allows the physically based model analysis of commercial LWR-type fuels at high burnup as well as analysis of experimental fuel rods tested in the Halden heavy water reactor, which is one of the main test reactors in the world. The differences in fuel behavior in the Halden reactor in terms of burnup distribution and plutonium buildup can be more clearly understood with the PLUTON model

Isotopic characteristics (Nd and Sr) of the intrusive plutonism at the northwestern Amazonian Craton, Venezuela, and implications for the Paleoproterozoic evolution

International Nuclear Information System (INIS)

Teixeira, Wilson; Tassinari, Colombro Celso G.; Mondin, M.

2002-01-01

Nd and Sr analyses were performed on selected granitoid plutons that intrude Archean and Paleoproterozoic domains of the Guyana shield (Venezuela). The isotopic signatures of these plutons together with the geochronologic background of the country rocks are used to constrain their magma genesis and tectonic setting within the Paleoproterozoic evolutions of mobile belts (Maroni-Itacaiunas and Ventuari-Tapajos provinces) of the Amazonian Craton. The Encrucijada Suite (2187 +- 94 Ma), which intrudes Archean rocks of the Imataca Complex, originated predominantly from partial melt of this crust, as supported by negative epsilon Nd(2.1Ga ) values (-2.2 to - 4.9) and T DM ages between 2.82 and 2.49 Ga. Conversely, the plutons from the Supamo Complex (2230 - 2050 Ma) and Cuchivero Group (1980 - 1830 Ma), occurring within the adjoining Paleoproterozoic provinces, are juvenile in nature (derived from roughly contemporary protoliths). These bodies display T DM ages between 2.13 and 2.22 Ga, as well as positive epsilon Nd(2.1Ga ) values (+0.74 to + 3.05). Isotopic correlation diagrams 143 Nd/144 Nd vs. 147 Sm/144 Nd and 143 Nd/144 Nd vs. time) plotted together with the plutonic rocks and Imataca Complex rocks were evaluated taking into account the geologic background of the NW part of the Amazonian Craton. Interpretation of these isotopic data supports the idea of tectonic juxtaposition between the Imataca Complex and the Maroni-Itacaiunas province during the Transamazonian orogeny (2.25 - 2.05 Ga). On the other hand, the Cuchivero Group plutons have a contrasting isotopic signature compared to the other Paleoproterozoic plutonic rocks. This is consistent with the existence of a tectonic boundary between the Maroni-Itacaiunas and the Ventuari-Tapajos province in the late Paleoproterozoic. (author)

Multistage magma emplacement and progressive strain accumulation in the shallow-level Krkonoše-Jizera plutonic complex, Bohemian Massif

Science.gov (United States)

Žák, Jiří; Verner, Kryštof; Sláma, Jiří; Kachlík, Václav; Chlupáčová, Marta

2013-09-01

relationships combined with new U-Pb zircon geochronology suggest that the shallow-level Krkonoše-Jizera plutonic complex, northern Bohemian Massif, was assembled successively from bottom to top, starting with emplacement of the separately evolved S-type Tanvald granite (317.3 ± 2.1 Ma), followed by at least two voluminous batches of the I-type porphyritic Liberec (319.5 ± 2.3 Ma) and Jizera (320.1 ± 3.0 Ma and 319.3 ± 3.7 Ma) granites. The intrusive sequence was completed by uppermost, minor intrusions of the equigranular Harrachov (315.0 ± 2.7 Ma) and Krkonoše granites. The I-type granites exhibit an unusually complex pattern of superposed feldspar phenocryst and magnetic fabrics as revealed from the anisotropy of magnetic susceptibility (AMS). The outer Liberec granite preserves margin-parallel foliations and lineations, interpreted to record emplacement-related strain captured by cooling from the pluton floor and walls. In contrast, the inner Jizera, Harrachov, and Krkonoše granites were overprinted by synmagmatic strain resulting from dextral movements along regional strike-slip faults cutting the opposite ends of the plutonic complex. Late-stage felsic dikes in the Liberec and Jizera granites reorient from horizontal to vertical (lineation-perpendicular) attitude in response to changing the least principal stress direction, whereas mafic schlieren do not do so, representing only randomly oriented small-scale thermal-mechanical instabilities in the phenocryst framework. In general, this case example challenges the common approach of inferring pluton-wide magma flow from interpolated foliation, lineation, and schlieren patterns. More likely, magmatic fabrics in large plutons record complex temporal succession of superposed strains resulting from diverse processes at multiple scales.

ORDEN MONETARIO DE LAS ECONOMÍAS DE MERCADO

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Michel Aglietta

2002-06-01

Full Text Available Al explicar el mercado a partir de la institución monetaria y no al revés, como es costumbre en los economistas, este artículo ofrece una nueva visión para comprender la naturaleza del dinero, las condiciones de viabilidad de la sociedad de mercado, el origen y control de las crisis financieras y monetarias y finalmente, tratar la independencia del Banco Central como una organización institucional particular que se propone para la regulación del sistema cada día más globalizado.

Fire Management Lessons Learned From the Cerro Grande (Los Alamos) Fire and Actions Needed to Reduce Fire Risks

National Research Council Canada - National Science Library

Hill, Barry

2000-01-01

We are here today to discuss two related issues, lessons learned from the recent Cerro Grande fire, and, on a broader note, actions needed to mitigate current hazardous forest conditions in the interior West...

Petrography and geochemistry of five granitic plutons from south central Uruguay: contribution to the knowledge of the Piedra Alta terrane

International Nuclear Information System (INIS)

Preciozzi, F.

2005-01-01

Granitoid rocks in south-central Uruguay are largely concentrated in three east-west trending metamorphic belts, known as (from south to north) the Montevideo Belt, the San José Belt and the Arroyo Grande Belt. These belts are separated from one another by intervening bands of gneisses of granitic composition. The whole assemblage, the gneisses as well as the metamorphic belts and their associated granites, collectively constitute the Piedra Alta Terrane. Five of these granite plutons, two from the San José Belt and three from the Arroyo Grande Belt, have been studied in some detail and the chemical composition of 86 samples (major elements as well as a selected suite of trace elements) have been determined. These data, as well as Rb-Sr isotopic data, show that these plutons are typically composite in nature, and that the various units range in age from 1900 Ma to 2500 Ma. The older ages were obtained from the main units of the plutons themselves whereas the younger ages are from late dykes which were emplaced into the plutons and which are clearly not related to them. The plutons are predominantly, but not exclusively, of calc-alkaline affinity and are typically synorogenic whereas the dykes are post-orogenic and are either calc-alkaline or alkaline in composition. These data have been incorporated into a tectonic model for the Piedra Alta Terrane which is considerably different from that heretofore proposed. The essential features of the geological history of the area are: 1) development of an older ''basement'' of granitic gneisses 2) deposition, upon or adjacent to this gneisses basement, of a typical Archean greenstone belt assemblage (no komatiites so far reported) 3) Paleo-proterozoic metamorphism, followed by syn-tectonic to post-tectonic intrusion of the plutonic rocks 4) major tectonic dislocation(s) associated with the Transamazonian orogeny 5) dyke emplacement (post-orogenic to anorogenic) following the Transamazonian orogeny

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

MERCADO, OPINIÓN PÚBLICA Y SOCIOLOGÍA EN ARGENTINA

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Juan Pedro Blois

2014-01-01

Full Text Available Aquí se analizan las relaciones entre investigación de mercado, opinión pública y sociología en Argentina. Se exami - nan diversas dimensiones del trabajo de los sociólogos dedicados a la consultoría de mercado y opinión: ingreso en la actividad, diferencias entre investigación de mercado y estudios de opinión pública, relaciones con clientes y emplea - dores, vinculaciones con instituciones y pares académicos. Se afirma que la sociología académica y la aplicada a la consultoría tienden a configurarse según cánones divergentes, lo cual limita los intercambios entre uno y otro mundo.

Estado, mercado de tierra urbana e inundaciones en ciudades argentinas

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Nora Clichevsky

2006-01-01

Full Text Available En este trabajo se presentan los resultados de una investigación sobre las relaciones que se establecen entre los mercados de tierra urbana y las inundaciones en ciudades argentinas, en el marco más amplio de la vulnerabilidad urbana. Se pretende despejar incógnitas acerca del papel jugado por el Estado como regulador del mercado en áreas urbanas con vulnerabilidad natural a la inundación y como constructor de defensas contra las inundaciones y acerca de los impactos que han tenido las inundaciones y las obras de defensa contra ellas sobre el mercado de tierra y, por lo tanto, sobre el acceso al suelo urbano por parte de los distintos sectores de la población.

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.

GEOCHEMICAL CHARACTERISTICS OF TIANMENSHAN COMPOSITE PLUTON, SOUTH CHINA

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Yanjiao Chen

2017-01-01

Full Text Available The southern Jiangxi province is located at east Nanling range, which is an important W-Sn metallogenic province of China. The Early Yanshanian Tianmenshan is composed of the main-phase porphyritic biotite granite and the highly differentiated fine-gained biotite granite, intruding in the Lower Cambrian Niujiaohe Formation. The main-phase granite and the late-stage highly differentiated granite emplaced at 152–158 Ma and 152–151 Ma, respectively. The later was in the center of the pluton as a ovalize shape, with a transitional contact with the main-phase granite.

Guidelines to classification and nomenclature of Arabian felsic plutonic rocks

Science.gov (United States)

Ramsay, C.R.; Stoeser, D.B.; Drysdall, A.R.

1986-01-01

Well-defined procedures for classifying the felsic plutonic rocks of the Arabian Shield on the basis of petrographic, chemical and lithostratigraphic criteria and mineral-resource potential have been adopted and developed in the Saudi Arabian Deputy Ministry for Mineral Resources over the past decade. A number of problems with conventional classification schemes have been identified and resolved; others, notably those arising from difficulties in identifying precise mineral compositions, continue to present difficulties. The petrographic nomenclature used is essentially that recommended by the International Union of Geological Sciences. Problems that have arisen include the definition of: (1) rocks with sodic, zoned or perthitic feldspar, (2) trondhjemites, and (3) alkali granites. Chemical classification has been largely based on relative molar amounts of alumina, lime and alkalis, and the use of conventional variation diagrams, but pilot studies utilizing univariate and multivariate statistical techniques have been made. The classification used in Saudi Arabia for stratigraphic purposes is a hierarchy of formation-rank units, suites and super-suites as defined in the Saudi Arabian stratigraphic code. For genetic and petrological studies, a grouping as 'associations' of similar and genetically related lithologies is commonly used. In order to indicate mineral-resource potential, the felsic plutons are classed as common, precursor, specialized or mineralized, in order of increasing exploration significance. ?? 1986.

The distribution, geochronology and geochemistry of early Paleozoic granitoid plutons in the North Altun orogenic belt, NW China: Implications for the petrogenesis and tectonic evolution

Science.gov (United States)

Meng, Ling-Tong; Chen, Bai-Lin; Zhao, Ni-Na; Wu, Yu; Zhang, Wen-Gao; He, Jiang-Tao; Wang, Bin; Han, Mei-Mei

2017-01-01

Abundant early Paleozoic granitoid plutons are widely distributed in the North Altun orogenic belt. These rocks provide clues to the tectonic evolution of the North Altun orogenic belt and adjacent areas. In this paper, we report an integrated study of petrological features, U-Pb zircon dating, in situ zircon Hf isotope and whole-rock geochemical compositions for the Abei, 4337 Highland and Kaladawan Plutons from north to south in the North Altun orogenic belt. The dating yielded magma crystallization ages of 514 Ma for the Abei Pluton, 494 Ma for the 4337 Highland Pluton and 480-460 Ma for the Kaladawan Pluton, suggesting that they are all products of oceanic slab subduction because of the age constraint. The Abei monzogranites derived from the recycle of Paleoproterozoic continental crust under low-pressure and high-temperature conditions are products of subduction initiation. The 4337 Highland granodiorites have some adakitic geochemical signatures and are sourced from partial melting of thickened mafic lower continental crust. The Kaladawan quartz diorites are produced by partial melting of mantle wedge according to the positive εHf(t) values, and the Kaladawan monzogranite-syenogranite are derived from partial melting of Neoproterozoic continental crust mixing the juvenile underplated mafic material from the depleted mantle. These results, together with existing data, provide significant information about the evolution history of oceanic crust subduction during the 520-460 Ma. The initiation of subduction occurred during 520-500 Ma with formation of Abei Pluton; subsequent transition from steep-angle to flat-slab subduction at ca.500 Ma due to the arrival of buoyant oceanic plateaus, which induces the formation of 4337 Highland Pluton. With ongoing subduction, the steep-angle subduction system is reestablished to cause the formation of 480-460 Ma Kaladawan Pluton. Meanwhile, it is this model that account for the temporal-spatial distribution of these early

Microstructures and magnetic fabrics of the Ngaoundéré granite pluton (Cameroon): Implications to the late-Pan-African evolution of Central Cameroon Shear Zone

Science.gov (United States)

Dawaï, Daouda; Tchameni, Rigobert; Bascou, Jérome; Awe Wangmene, Salomon; Fosso Tchunte, Périclex Martial; Bouchez, Jean-Luc

2017-05-01

The Ngaoundéré granite pluton, in Central-North Cameroon, located near the Central Cameroon Shear zone (CCSZ), and previously studied for its petrography and geochemistry, is characterized by the absence of macroscopic markers of deformation. In this study, we report microstructures and magnetic fabrics (AMS) of this pluton and discuss the relationship with the Pan-African evolution of the CCSZ. The pluton consists of a porphyritic Hbl-Bt-monzogranite at its rim and a porphyritic biotite-granite at its core, a petrographic distribution denoting a normal zoning pattern, i.e. more silicic toward the centre. As expected, magnetic susceptibilities values also exhibit a zoning pattern in agreement with petrographic zonation. Thermomagnetic data indicate that this pluton is dominantly ferromagnetic in behaviour. As indicated by its microstructures, the pluton has suffered a continuum of deformation from the magmatic state to the high temperature solid-state during magma crystallization and solidification. The magnetic foliations dominantly strike NE-SW and dip moderately to steeply and the lineations mostly plunge shallowly to the NE or SW, roughly parallel to NE-to ENE-trending Central Cameroun Shear Zone (CCSZ). The foliation poles define a girdle pattern with a zone axis (52°/11°) rather close to the best line of the lineations (44°/21°). These fabrics correlate with the structures of the country rocks ascribed by several workers to a regional transpression. Toward the margins of the pluton, particularly the northern one, the lineations tend to rotate from NE to N in azimuth. This change is interpreted as due to strain partitioning, simple shearing with NE-SW extension being relayed by compression toward the northern pluton border. This new magnetic fabric study suggests that the Ngaoundéré pluton (poorly dated at c. 575 Ma) was emplaced during the late stages of the CCSZ dextral transpressive movement. It also provides some more constraints on the correlation

Composition of coarse-grained magnetite from pegmatite dikes related to plutons of quartz monzonite in the Jabal Lababa area, Kingdom of Saudi Arabia

Science.gov (United States)

Overstreet, William C.; Mousa, Hassan; Matzko, John J.

1985-01-01

Crystals of magnetite as large as 30 mm long and 7 mm thick are locally present in quartz-rich zones of interior and exterior pegmatite dikes related to plutons of quartz monzonite in the Jabal Lababa area. Niobium, tin, and yttrium are strongly enriched in six specimens of magnetite from interior pegmatite dikes in a small pluton where these elements form geochemical anomalies in nonmagnetic heavy-mineral concentrates from wadi sediment. Less abundant anomalous elements in the magnetite are molybdenum, lead, and zirconium, which also tend to be present in anomalous amounts in the nonmagnetic concentrates from the niobium-bearing pluton. The most anomalous trace element in the magnetite is zinc, which is at least 10 times as abundant as it is in the quartz monzonite plutons or in the nonmagnetic concentrates. The capacity of magnetite to scavenge molybdenum, zinc, niobium, lead, tin, yttrium, and zirconium suggests the possible utility of magnetite as a geochemical sample medium.

Genesis of zoned granite plutons in the Iapetus Suture Zone: new constraints from high-precision micro-analysis of accessory minerals

OpenAIRE

Miles, Andrew James

2013-01-01

The Trans-Suture Suite (TSS) of granitic plutons located in Northern Britain span the Iapetus Suture and represent a particularly enigmatic stage of post-Caledonian Devonian magmatism. Despite calc-alkaline affinities, proximity to the Iapetus Suture precludes a direct relationship to active subduction. Furthermore, the absence of inherited zircons distinguishes the TSS from plutons of a similar age throughout the Scottish Highlands, and is not easily reconciled with the abunda...

U-Pb ages and Hf isotope compositions of zircons in plutonic rocks from the central Famatinian arc, Argentina

Science.gov (United States)

Otamendi, Juan E.; Ducea, Mihai N.; Cristofolini, Eber A.; Tibaldi, Alina M.; Camilletti, Giuliano C.; Bergantz, George W.

2017-07-01

The Famatinian arc formed around the South Iapetus rim during the Ordovician, when oceanic lithosphere subducted beneath the West Gondwana margin. We present combined in situ U-Th-Pb and Lu-Hf isotope analyses for zircon to gain insights into the origin and evolution of Famatinian magmatism. Zircon crystals sampled from four intermediate and silicic plutonic rocks confirm previous observations showing that voluminous magmatism took place during a relatively short pulse between the Early and Middle Ordovician (472-465 Ma). The entire zircon population for the four plutonic rocks yields coherent εHf negative values and spreads over several ranges of initial εHf(t) units (-0.3 to -8.0). The range of εHf units in detrital zircons of Famatinian metasedimentary rocks reflects a prolonged history of the cratonic sources during the Proterozoic to the earliest Phanerozoic. Typical tonalites and granodiorites that contain zircons with evolved Hf isotopic compositions formed upon incorporating (meta)sedimentary materials into calc-alkaline metaluminous magmas. The evolved Hf isotope ratios of zircons in the subduction related plutonic rocks strongly reflect the Hf isotopic character of the metasedimentary contaminant, even though the linked differentiation and growth of the Famatinian arc crust was driven by ascending and evolving mantle magmas. Geochronology and Hf isotope systematics in plutonic zircons allow us understanding the petrogenesis of igneous series and the provenance of magma sources. However, these data could be inadequate for computing model ages and supporting models of crustal evolution.

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 Cyanobacteria and Ktedonobacteria, however Actinobacteria, alpha-Proteobacteria and Acidobacteria were also identified. Many of the cyanobacterial sequences were similar to those of the eukaryotic Cyanidiales, 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.

EMPREENDEDORISMO JOVEM: DA ESCOLA PARA O MERCADO DE TRABALHO

OpenAIRE

Gomes, Danilo Cortez; Professor de Administração no IFRN - Campus Currais Novos.; de Farias Silva, Luciano Alexandre; Aluno do curso técnico integrado em informática do IFRN - Campus Currais Novos.; D´Anjour, Miler Franco; PPGA/UFRN; Moreno Añez, Miguel Eduardo; PPGA/UFRN

2014-01-01

O empreendedorismo jovem apresenta-se como forma de inclusão de jovens no mercado de trabalho e em contrapartida é fator preponderante para promoção do desenvolvimento socioeconômico brasileiro (LIMA-FILHO, SPROESSER, MATINS, 2009). Nesta perspectiva, o objetivo central desse artigo é discutir o ensino do empreendedorismo para os jovens utilizando como “case” o projeto “Empreendedorismo jovem: da escola para o mercado de trabalho” que buscou estimular os alunos do IFRN – Campus Currais Novos ...

Magma flow paths and strain patterns in magma chambers growing by floor subsidence: a model based on magnetic fabric study of shallow-level plutons in the Stiavnica volcano-plutonic complex, Western Carpathians

Czech Academy of Sciences Publication Activity Database

Tomek, Filip; Žák, J.; Chadima, Martin

2014-01-01

Roč. 76, č. 11 (2014), Article 873 ISSN 0258-8900 Institutional support: RVO:67985831 Keywords : anisotropy of magnetic susceptibility (AMS) * caldera * intrusive strain * magma emplacement * pluton floor subsidence * stratovolcano Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.519, year: 2014

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

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Chantal CRAMAUSSEL

2014-01-01

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

Perspectivas del Mercado de Derivados en Colombia Retraso derivado del desconocimiento Perspectivas del Mercado de Derivados en Colombia Retraso derivado del desconocimiento

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Natalia Cañas Arboleda

2006-12-01

Full Text Available El mercado de derivados representa la evolución de los mercados financieros enel mundo, debido a la capacidad que tiene el primero de ofrecer cobertura a losparticipantes del mercado, función importante en el actual contexto de globalización.Por lo anterior, en el país se desarrollan, aunque un poco tarde, diversos proyectospara la incorporación de futuros y opciones, como nuevas alternativas de inversióny financiación que redunden en menor incertidumbre para los inversionistas dediferentes sectores de la economía. A partir de allí, se muestra la situación actualdel mercado de derivados en Colombia y los esfuerzos realizados por diferentesinstituciones, encaminados al desarrollo del mismo.The derivative market represents the evolution of financial markets in the world, given the capacity that the former has for offering coverage to market participants, which is an important feature in the present context of globalization. For this reason, some projects are being developed in our country, though  a bit late, for the incorporation of futures and options, as new investment and financing alternatives, which may result in a reduced uncertainty for the investors in different sectors of the economy. This article shows the current situation of the derivative market in Colombia and the efforts made by different institutions, aimed at the development of such a market.

Medio ambiente, mercado y Estado

OpenAIRE

Duque Escobar, Gonzalo

2014-01-01

La fuerza del mercado frente a las falencias del Estado, como factores que explican las barreras para el desarrollo de la vacuna sintética contra la malaria en Colombia y la falta de control a las causas antrópicas del ecosidio de los chigüiros en el desierto de muerte del Casanare

K, Rb and Sr abundances and Sr isotopic composition of the Tanzawa granitic and associated gabbroic rocks, Japan: low-potash island arc plutonic complex

International Nuclear Information System (INIS)

Ishizaka, K.; Yanagi, T.

1977-01-01

The granitic and associated gabbroic rocks of the Tanzawa plutonic complex of Miocene age occurring in the northern part of the Izu-Bonin arc are characterized by low abundances of K (229-6790 ppm) and Rb (0.414-12.1 ppm), low K 2 O/Na 2 O ratios (0.037-0.21), moderately high K/Rb ratios (541-630), low Rb/Sr ratios (0.00137-0.0579) and low initial 87 Sr/ 86 Sr ratios (0.70332-0.70372). This indicates that acid to intermediate plutonic rocks with these geochemical characteristics also occur in island arc environments besides mid-oceanic ridge environments. They represent, together with associated gabbroic rocks, a low-potash island arc plutonic complex and are expected to occur beneath young island arcs, although now unexposed. The Tanzawa plutonic complex may have been formed by differentiation of low-K calc-alkaline magma. (Auth.)

Petrografía, caracterización geoquímica y análisis microestructural del granito del cerro Siempre Amigos, sierras de Azul, Tandilia

OpenAIRE

Angeletti, Melisa; Frisicale, María Cristina; Dimieri, Luis V

2016-01-01

El cerro Siempre Amigos integra las sierras de Azul, Tandilia, distante 28 km al sur de la ciudad de Azul y 3 km al norte de la megacizalla de Azul, zona de cizalla subvertical donde el basamento se encuentra deformado a milonitas y ultramilonitas. La litología predominante en el cerro Siempre Amigos es un granito paleoproterozoico deformado que en el centro y hacia los bordes se encuentra interdigitado con una roca gnéisica y cuerpos de anfibolitas subverticales de rumbo similar a la foliaci...

Mineralization related to Alvand pluton in the Hamadan, western Iran

Science.gov (United States)

Salehi, M. H.; Doosti, E. A.; Ahadnejad, V.

2009-04-01

The Alvand (Hamadan) plutonic batholith is one of the largest plutonic bodies in the Sanandaj-Sirjan metamorphic belt. This complex is consist of mafic part (gabbro-diorite-tonalite), intermediate (granite-granodiorite porphyroids), and hololeucocratic granitoids. Previous studies have shown that S-type granite-granodiorites are mostly peraluminous and calc-alkaline; the gabbro-diorite-tonalite suite is mostly metaluminous and tholeiitic to calc-alkaline (Sepahi, 2008). High initial 87Sr-86Sr ratios (0.7081 to 0.7115), low epsilon Nd values (-1.0 to -3.3), and peraluminous character reflects a different origin for the granites, possibly crustal sources (Ghalamghash et al, 2007). Aplite-pegmatite dikes are intruded in granitoide rocks, metamorphic rocks and the contact of Alvand granite with metamorphic rocks. The contact of Alvand granite with metamorphic rocks is sharp. By using heavy mineral studies on the alluvium of Alvand complex, it is recognized 28 minerals amongst Scheelite, Cassiterite, Ilmenite, Zircon and Garnet. Different geostatistical studies such as variant, bivariant and multivariant studies have been done on rough data of heavy minerals. They showed normal concentration of gold in studied rocks and low enrichment of tin and tungsten. The index of the ore elements average, frequeney distribution criteria of elements, the ratio of elements index and multielements show that Alvand granite is barren. Mineralography studies did not recognized any tin and tungsten minerals. The grains of gold was recognized in some of the microscopic thin sections. Calcopyrotite is the most important ore mineral that is accompanied with oxides and iron carbonates. The contacts of aplite-pegmatite dikes with granitoide rocks mostly are not prolific. For recognizing Scheelite, some samples of rocks studied by ultraviolet and few Scheelite is recognized in the samples. Some alteration zone observed in this area but they are not accompany with main mineralization. Although

Estudio de Mercado para Desarrollar el Proyecto de Exportación de Mermeladas Orgánicas Motuche Gourmet al Mercado de Alemania

OpenAIRE

Dávila Moreno, Andrea; Espinosa Cordero, Denise

2010-01-01

La empresa familiar Indartbio, bajo la marca de Motuche Gourmet, ha lanzado al mercado nacional e internacional sus 6 tipos de mermeladas, que combinan frutas exóticas y dan al consumidor un producto de excelente calidad y con certificación orgánica. En el año 2008, los productos Motuche Gourmet fueron expuestos en la feria BioFach en Alemania, lo que les permitió encontrar sus primeros clientes alemanes y les hizo ver la posibilidad de entrar en dicho mercado con sus mermeladas. Por esta raz...

Isotopic studies of the Eye-Dashwa Lakes pluton and the long-term integrity of whole-rock and mineral systems

International Nuclear Information System (INIS)

Peterman, Z.E.; Kamineni, D.C.

1990-05-01

This report presents results of isotopic studies of the Eye-Dashwa Lakes pluton, located near Atikokan, Ontario. Suites of pristine unaltered and highly altered core samples from deep boreholes were used to study Rb-Sr, U-Th-Pb and Sr-Nd systematics, whole-rock Pb isotopes and fission track dating of apatite. The results have been used to investigate natural analogues for radionuclide migration in the geosphere, the tectonic stability of the pluton and the extent of water-rock interaction in fracture zones

Subsurface imaging in a sector of Cerro Prieto transform fault near to pull-apart basin, Mexicali Valley, Baja California, Mexico, based on crooked lines 2D seismic reflection.

Science.gov (United States)

Mares-Agüero, M. A.; González-Escobar, M.; Arregui, S.

2016-12-01

In the transition zone between San Andres continental transformation system and the coupled transform faults system and rifting of Gulf of California is located the Cerro Prieto pull-apart basin delimitated by Imperial fault (northeast) and Cerro Prieto fault (CPF) (southwest), this last, is the limit west of Cerro Prieto geothermic field (CPGF). Crooked lines 2D seismic reflection, covering a portion near the intersection of CPF and CPGF are processed and interpreted. The seismic data were obtained in the early 80's by Petróleos Mexicanos (PEMEX). By decades, technical and investigation works in Cerro Prieto geothermic field and its vicinity had mapped faults at several depths but do not stablish a clear limit where this faults and CPF interact due the complex hydrothermal effects imaging the subsurface. The profiles showing the presence of a zone of uplift effect due to CPF. Considering the proximity of the profiles to CPF, it is surprising almost total absence of faults. A strong reflector around 2 km of depth, it is present in all profiles. This seismic reflector is considered a layer of shale, result of the correlation with a well located in the same region.

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

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William H.J. Strosnider

2015-06-01

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

Magmatic Flow Record From AMS Data La Gloria Pluton, Central Chile

Science.gov (United States)

Gutierrez, F.; Payacan, I. J.; Calderon, S.

2011-12-01

La Gloria Pluton (LGP) is a 10 Ma epizonal intrusion in the Southern Andes, located 40 km east of Santiago, in central Chile. 20 km long and 5 km wide LPG has a thickness of 2.5 km, in the form of a NW elongating inverted canoe. LGP intrudes Miocene volcanics as NS extending cluster of Miocene granitoids. LGP was emplaced at the west of an inverse fault system without exhibiting significant post-intrusion deformation. The fault system includes the Laguna Negra Fault and the El Coironal Fault, at its southern and northern ends respectively. LGP has been interpreted to have had a short cooling time, where subsolidus reequilibration was not pervasive, allowing identification of early and late magmatic conditions and suggesting it to be a single closed chamber. LGP is zoned vertically from granodiorite/quartz monzodiorite to quartz monzonite towards the roof, where hornblende and biotite and minor magnetite-ilmenite are omnipresent. AMS samples were collected at 39 sites to determine of the magnetic anisotropy susceptibility tensor. Magnetic fabric is generally oblate and anisotropy values range from 1.3 to 13.9%, consistent with the prescience magnetite and ilmenite. Magnetic lineation (ML) has a NNW trend, a subhorizontal dip and values between 0.4 and 5.3%. Magnetic foliation (MF) has a NW trend and dip varying from vertical at the walls of the intrusive to subhorizontal inside and under the roof. MF values ranges between 0.8 and 13.3%. Since linear trend of MF is restricted to the LGP interior only and can not be caused by a simple inverse fault system, we interpret the AMS results as a consequence of magmatic flow. ML represents the main flow direction, where several shallow plutons intrude at 10Ma in NW direction. MF is consequence of convection, related to cooling and differentiation, and is comparable to numerical simulations of magma fluid-dynamics during differentiation (R4). Two profiles (EW and NS) indicate that MF linear trend is from 29°/km to 50�

LA ARQUITECTURA DE TIERRA Y LAS OCUPACIONES HUMANAS EN EL SITIO ARQUEOLÓGICO CERRO PUÑAY, CANTÓN CHUNCHI, PROVINCIA DE CHIMBORAZO, ECUADOR (Earth Architecture and Human Occupations at Cerro Puñay Archaeological Site, Chunchi Canton, Chimborazo Province, Ecuador

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Mary Jadán V.

2017-06-01

Full Text Available Este artículo se refiere a la arquitectura de tierra del sitio arqueológico Cerro Puñay, ubicado al sur de la provincia de Chimborazo. Algunos perfiles estratigráficos de diferentes partes del cerro demuestran que existen cambios relacionados con la estructura del sitio: un reforzamiento de talud en la cima central, arqueosedimentos en ciertos sectores, nivelación de las cimas, construcción de terrazas, entre otras modificaciones. Aunque hay evidencias de ocupación desde el Formativo Tardío con la cultura narrío (2000-1600 a. C., las edificaciones se iniciaron con la sociedad cañari (500-1460 d. C.. Por otra parte, el sitio evidencia una reconstrucción y utilización por parte de la sociedad inca (1460-1533 d. C.. ENGLISH: This article refers to the land architecture of the Cerro Puñay archaeological site, located to the south of the province of Chimborazo. Some stratigraphic profiles, from different parts of the hill, show that there are changes related to the structure of the site: a reinforcement of slope in the central summit, archaeological sediments in certain sectors, leveling of the tops, and construction of terraces, among other modifications. Although there is evidence of occupation from the Late Formative with the Narrío culture (2000–1600 BC, the construction started with the Cañari society (500–1460 AD. On the other hand, the site shows evidence of a reconstruction and use by the Inca society (1460–1533 AD.

Revisión de herramientas aplicadas al modelamiento de mercados de electricidad

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Sandra Milena Londoño Hernández

2009-09-01

Full Text Available La desregulación de los mercados de electricidad alrededor del mundo, en la búsqueda de la eficiencia, ha introducido compe- tencia en los sectores de comercialización y generación de energía. Por esta razón, ha adquirido gran importancia, para regula- dores y oferentes, estudiar la interacción de los agentes competitivos para analizar la evolución del mercado y definir adecuada- mente estrategias de ofertamiento. Por lo tanto, en los últimos años se han utilizado diferentes herramientas para modelar los mercados de electricidad competitivos; este artículo presenta una revisión analítica de la bibliografía encontrada en el tema, en la cual se presentan las herramientas más utilizadas, además de sus ventajas y desventajas. Para realizar este análisis se hicieron comparaciones entre los modelos utilizados en cada herramienta, identificando las principales características del mercado, tales como esquema de mercado, estructura de las ofertas, tipo de subasta, entre otras. De este análisis se concluye que el tipo de herramienta a utilizar depende en gran medida del objetivo y alcance que se busca con el estudio.

Characteristics and mode of emplacement of gneiss domes and plutonic domes in central-eastern Pyrenees

Science.gov (United States)

Soula, Jean-Claude

Gneiss domes and plutonic granitoid domes make up almost 50% of the pre-Hercynian terrains in the Central and Eastern Pyrenees. From a structural study of the shape and internal structure of the domes and of their relationships with the enclosing rocks, it can be shown that both types of domes were emplaced diapirically during the major regional deformation phase and the peak of regional metamorphism. The study also shows that the internal structure, the overall shape and general behaviour relative to the host rocks are similar for plutonic domes and for gneiss domes. This appears to be in good agreement with H. Ramberg's (1967, Gravity Deformation and the Earth's Crust. Academic Press, London; 1970, Model studies in relation to intrusion of plutonic bodies. In: Mechanisms of Igneous Intrusion (edited by Newall, G. & Rast, N.) Geol. J. Spec. Issue2, 261-286.) model studies showing that dome or mushroom-like structures, similar to those observed, develop when there is a small viscosity ratio between the rising body and its enclosing medium. This implies a high crystal content for the granitoid magma. This crystal content has been estimated by (i) calculating the viscosity and density in natural conditions from petrological data for the magma considered as a suspension, using the model and program of J. P. Carron et al. (1978 Bull Soc. géol. Fr.20, 739-744.); (ii) using the recent results of experimental deformation of partially melted granites of I. van der Molen & M. S. Paterson (1979, Contr. Miner. Petrol.70, 299-318.) and (ii) comparing the preceding results with the data obtained by deformation experiments on rocks similar to those enclosing the domes. The minimum crystal content for the development of a dome-like structure has been, thus, estimated to about 70%, i.e. a value very close to that estimated by van der Molen & Paterson (1979) to be the critical value separating the granular framework flow from suspension-like behaviour. The effect of small

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

Orden monetario de las economías de mercado

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Aglietta Michel

2002-08-01

Full Text Available Al explicar el mercado a partir de la institucióm monetaria y no al revés, como es la costumbre en los economistas, este articulo ofrece una nueva visión para comprender la naturaleza del dinero, las condiciones de la viabilidad de la sociedad de mercado, el origen y control de las crisis financieras y monetarias, y finalmente, tratar la independencia del Banco Central como una organización institucional particular que se propone para la regulacion del sistema cada día ás globalizado.

Concentración de mercado en el sector de telecomunicaciones en Venezuela

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María Cristina Useche

2008-01-01

Full Text Available El objeto de la investigación fue establecer el grado de concentración de las operadoras habilitadas que se desempeñan en los segmentos de mercado de telefonía fi ja local y telefonía móvil celular en Venezuela para el período 2004-2007, permitiendo tener una visión de las empresas que tienen poder de mercado en el sector de telecomunicaciones en el país. Para ello se tomo como referencia el índice de Herfi ndahl-Hirschman (IHH. Se recopiló información gubernamental sobre este segmento de mercado regulado nacional. Se concluyó que existe un alto nivel de concentración en cada rubro, siendo las operadoras habilitadas CANTV y MOVISTAR las que tienen el poder del mercado en las telecomunicaciones a nivel nacional, afectando la competencia y desestimulando a otras empresas a desempeñarse en el ámbito nacional

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.

Three-dimensional cooling pattern of a granitic pluton 2. The study of deuteric sub-solidus reactions in the Toki granite, Central Japan

International Nuclear Information System (INIS)

Yuguchi, Takashi; Tsuruta, Tadahiko; Nishiyama, Tadao

2011-01-01

Petrographical studies examining the development and variations of sub-solidus reactions recorded in the Toki granite represent the three-dimensional cooling pattern of this zoned pluton in Central Japan. Samples collected from 19 boreholes in the Toki granite show characteristics indicative of spatial variations in the extent of the sub-solidus reactions. Exsolution coarsening has produced microperthite, including albite-rich lamellae, in this pluton, while deuteric coarsening has resulted in the formation of patchperthite, myrmekite, and the reaction rim. The extent of the deuteric coarsening reactions can be evaluated from the width and spacing of the albite-rich patch in patchperthite and from the thickness of myrmekite and the reaction rim. The width, spacing, and thickness of these textural features increase systematically with elevation; they also increase gradually in the horizontal inward direction in the western part of the pluton but not in the eastern part of the pluton. The systematic variations in textural development indicate that the Toki granite cooled effectively from the roof and from the western margin during the deuteric coarsening stage. The deuteric coarsening may have occurred at temperatures below 500°C, as indicated by ternary feldspar thermometry. (author)

Comportamiento del Comercio Mundial de Palta y Perspectivas del Mercado Chino

OpenAIRE

Ministerio de Agricultura y Riego

2015-01-01

En el presente Reporte de la Situación de la Palta en el Mercado Internacional veremos los precios internacionales, la producción Mundial, La exportación Mundial, Exportaciones de México, Competencia con las exportaciones peruanas, Importación Mundial de Palta, Evolución de las exportaciones, las Perspectivas del Mercado Chino para la palta Peruana.

Volcanic-plutonic connections and metal fertility of highly evolved magma systems: A case study from the Herberton Sn-W-Mo Mineral Field, Queensland, Australia

Science.gov (United States)

Cheng, Yanbo; Spandler, Carl; Chang, Zhaoshan; Clarke, Gavin

2018-03-01

Understanding the connection between the highly evolved intrusive and extrusive systems is essential to explore the evolution of high silicic magma systems, which plays an important role in discussions of planetary differentiation, the growth of continents, crustal evolution, and the formation of highly evolved magma associated Sn-W-Mo mineral systems. To discern differences between "fertile" and "non-fertile" igneous rocks associated with Sn-W-Mo mineralization and reveal the genetic links between coeval intrusive and extrusive rocks, we integrate whole rock geochemistry, geochronology and Hf isotope signatures of igneous zircons from contemporaneous plutonic and volcanic rocks from the world-class Herberton Mineral Field of Queensland, Australia. The 310-300 Ma intrusive rocks and associated intra-plutonic W-Mo mineralization formed from relatively oxidized magmas after moderate degrees of crystal fractionation. The geochemical and isotopic features of the coeval volcanic succession are best reconciled utilizing the widely-accepted volcanic-plutonic connection model, whereby the volcanic rocks represent fractionated derivatives of the intrusive rocks. Older intrusions emplaced at 335-315 Ma formed from relatively low fO2 magmas that fractionated extensively to produce highly evolved granites that host Sn mineralization. Coeval volcanic rocks of this suite are compositionally less evolved than the intrusive rocks, thereby requiring a different model to link these plutonic-volcanic sequences. In this case, we propose that the most fractionated magmas were not lost to volcanism, but instead were effectively retained at the plutonic level, which allowed further localized build-up of volatiles and lithophile metals in the plutonic environment. This disconnection to the volcanism and degassing may be a crucial step for forming granite-hosted Sn mineralization. The transition between these two igneous regimes in Herberton region over a ∼30 m.y. period is attributed to

Cruzeiros marítimos: realidade da oferta e da demanda no mercado brasileiro

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Carlos Eduardo de Almeida Ramoa

2014-12-01

Full Text Available O turismo marítimo apresenta uma demanda crescente e constante nos Estados Unidos e na Europa. No Brasil, esse mercado vinha se destacando com crescimento exponencial da demanda, no entanto, a partir da temporada 2011/2012 a taxa de crescimento tem apresentado queda. Este estudo de caráter exploratório e descritivo utiliza o método de procedimento matemático e tem como objetivo geral identificar a realidade da oferta e da demanda no mercado brasileiro de cruzeiros marítimos. Para atingi-lo foram identificados os históricos da oferta e da demanda, no período de 2004 a 2013, e da situação atual da infraestrutura portuária, através da utilização de técnicas de documentação indireta, procedimento documental e bibliográfico. Para se comparar a taxa de crescimento do mercado brasileiro com os principais mercados foi realizado cálculo da extrapolação matemática exponencial. Os resultados apresentados indicam que o Brasil é o único país entre os dez maiores mercados de cruzeiros marítimos, que possui taxa de crescimento negativo, indicando haver uma crise no segmento de cruzeiros marítimos, cujo motivo aponta para os problemas estruturais como sendo uma das causas da queda da oferta e da demanda no mercado brasileiro.

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.

Risco de crédito ao consumidor: uma realidade do mercado brasileiro

OpenAIRE

Dayan, Carlos Moche

2010-01-01

Esta dissertação procura, em duas partes, retratar de forma crítica o mercado de crédito ao consumidor e pessoal no Brasil. Primeiramente, é descrita a forma operacional do sistema , através de dados e descrições práticas do mercado na atualidade. Uma especial atenção é dada à inadimplência, cuja estimativa é vital para a operação no mercado de crédito de varejo. Em uma segunda concessão de crédito parte, aspectos são abordados, com o respaldo de conceitos internacionais sobre o a...

O mercado de bens e serviços com apelos ambientais

Directory of Open Access Journals (Sweden)

Eliana Boaventura Bernardes Moura Alves

2013-12-01

Full Text Available A crescente conscientização ambiental da sociedade tem alavancado o consumo de produtos e serviços com apelo ambiental, formando o denominado “mercado verde”, que tem impulsionado a economia e estimulado o desenvolvimento sustentável. Este trabalho teve como objetivo analisar o mercado de bens e serviços com apelos ambientais e inferir sobre suas motivações e tendências. O método utilizado foi a pesquisa bibliográfica a fim de construir um estudo descritivo, que reunisse e compilasse informações deste mercado. Constatou-se que o marketing aliado à responsabilidade ambiental, vem alcançando cada vez mais espaço nos meios de comunicação das empresas e funciona como ferramenta estratégica, favorecendo a imagem corporativa e a competitividade, além de conquistar e fidelizar consumidores. O “mercado verde” revela tendências de crescimento, tanto no quesito número de consumidores, como também de competidores. Tal fato pode requerer um marketing mais agressivo e mais informativo por parte das empresas, no intuito de manter e conquistar novos clientes.

El papel del regulador en el mercado de las telecomunicaciones

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Carlos Alberto Herrera Barros

2006-05-01

Full Text Available La regulación de mercados surge ante la ausencia de competencia efectiva en un sector, lo cual generalmente produce que los agentes tienden a asumir comportamientos monopólicos y por tal motivo el regulador debe identificar las fallas de mercado a fin de corregirlas. Mientras se reduce la dispersión normativa del sector de telecomunicaciones en Colombia, el regulador debe reconocer el dinamismo de los mercados para garantizar el cumplimiento de los objetivos legales y regulatorios de promoción de la competencia y protección a los usuarios. Vale la pena entonces preguntarse si es cierto que en Colombia ya estamos en un mercado de telecomunicaciones en el cual existe un nivel de competencia tal, que se hace innecesaria la regulación sectorial ex-ante. Para esto, el autor hace un breve análisis de cuales son las realidades y perspectivas en algunos de los subsegmentos de mercado en el sector de telecomunicaciones, y finalmente cierra el escrito con algunas conclusiones relevantes sobre el tema. / Market regulation arises because of the absence of effective competition in a sector, where the players tend to assume monopolistic behaviors . Regulators must identify the market failures in order to correct them. As normative dispersion of different services rules the Colombian telecommunications sector, it's important that regulator approaches to market analysis through predictable and similar criteria which recognize the dynamism of the markets to guarantee legal and regulatory objectives of promotion of the competition and protection to the consumers .We wonder if It is true in Colombia we already are experiencing such a high competitive telecommunications market which does not needs ex-ante regulation.. the author makes a brief analysis of the perspectives and realities in some of the segments of market and finally the author closes the writing with some important conclusions about the subject.

Análisis de la competitividad del mercado primario de leche en Argentina.

OpenAIRE

Andrés Loza

2001-01-01

El mercado mayorista de leche en Argentina muestra una estructura apropiada para que las empresas tengan poder de mercado y se apropien de parte de la renta que correspondería a los productores rurales en un entorno competitivo. La presente investigación utiliza las modernas técnicas de la Nueva Organización Industrial Empírica, para resolver si las empresas mayoristas elaboradoras de leche ejercen su poder de mercado sobre el productor o tambero. Tanto las pruebas paramétricas y no paramétri...

El papel del mercado en la construcción de organizaciones sustentables

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Dante David Solís Santamaría

2017-01-01

Full Text Available El objetivo del artículo es discutir cómo el mercado propicia modificaciones estructura-les en las organizaciones que agilizan su tránsito hacia la sustentabilidad. Se discute y propone una estructura analítica que es contrastada en la producción de uva de mesa en Hermosillo, Sonora. La metodología con-siste en un análisis indirecto sobre las condi-ciones de mercado del sistema uva de mesa y un panel de entrevistas que incluyen el perfil del puesto, gerencia, mercado y toma de deci-siones realizadas a dieciocho gerentes selec-cionados de una población de 39 organizacio-nes productoras de uva de mesa con una muestra estadística al 95% de confianza y 7% de error. Resultados: La evidencia empírica señala que las condiciones de mercado actua-les se expresan en rigurosas certificaciones en los campos de responsabilidad social, inocui-dad, calidad, seguridad y producción orgáni-ca. Limitaciones: durante la investigación surgieron complicaciones logísticas que obli-garon a modificar la muestra. Conclusiones: las condiciones de mercado han demandado nuevos perfiles y han modificado las formas organizativas, mismas que transitan de es-tructuras verticales hacia estructuras sistémi-cas sustentables: un cambio de empresa a or-ganizaciones sustentables.

Geochronological, geochemical, and Sr-Nd-Hf isotopic characteristics of Cretaceous monzonitic plutons in western Zhejiang Province, Southeast China: New insights into the petrogenesis of intermediate rocks

Science.gov (United States)

Liu, Liang; Qiu, Jian-Sheng; Zhao, Jiao-Long; Yang, Ze-Li

2014-05-01

We present comprehensive petrological, geochemical, and Sr-Nd-Hf isotopic data for the Matou and Dalai plutons in western Zhejiang Province, Southeast China, with the aim of constraining the petrogenesis of monzonites and to offer new insights into the deep processes of interaction between crustal- and mantle-derived magmas beneath SE China. The Matou pluton comprises quartz monzonite, whereas the Dalai pluton consists of quartz monzodiorite. Zircon U-Pb ages obtained by laser ablation-inductively coupled plasma-mass spectrometry show that both plutons were emplaced at 99-101 Ma. Rocks of both plutons are intermediate to silicic, metaluminous to weakly peraluminous, subalkaline, and K-rich in composition. Samples of the plutons are enriched in large ion lithophile (e.g., Rb, K, and Pb) and light rare earth elements, depleted in high-field strength elements (e.g., Nb, Ta, and Ti), and have small negative or no Eu anomalies. In addition, the rocks have high Mg# values (up to 53.9), high zircon ɛHf(t) values (up to - 1.4), and low Nb/U and Ta/U ratios. Geochemical evidence suggests that both depleted asthenospheric and metasomatically enriched mantle components were involved in the formation of these monzonitic rocks. The presence of inherited zircons with Palaeoproterozoic ages and zircons with unusually low ɛHf(t) values (- 12.9) in the Matou quartz monzonites indicates that ancient crustal materials were also involved in their petrogenesis. In combination with the presence of abundant mafic microgranular enclaves (MMEs) with spheroidal to ellipsoidal-ovoidal shapes and xenocrysts within the more diffused enclaves, and the results of trace element modelling, we suggest that the Matou quartz monzonites were generated by mixing between mantle-derived mafic magmas and crustally derived silicic magmas. The Dalai pluton is relatively homogeneous and contains fewer MMEs than the Matou pluton. Zircons from the Dalai pluton show no inherited components, indicating that

The Transhimalaya (Gangdese) plutonism in the Ladakh region: A U-Pb and Rb-Sr study

International Nuclear Information System (INIS)

Schaerer, U.; Hamet, J.; Allegre, C.J.

1984-01-01

The age and origin of the Transhimalaya (Gangdese) plutonic belt in the Ladakh area has been studied by high-resolution U-Pb analyses of accessory minerals (zircon and monazite/allanite) and Rb-Sr measurements on whole rock samples. The ages determined of 101+-2 m.y. for a granodiorite and of 60.7+-0.4 m.y. for a granite substantiate that the Transhimalaya plutonism was active at least in mid-Cretaceous (Albian) and earliest Tertiary (Palaeocene) times. A Rb-Sr isochron of 73.4+-2.4 m.y. might be fortuitous because the Rb-Sr systematics shows important heterogeneities on the whole rock scale. The inherited radiogenic lead in zircon demonstrates that anatexis of continental crust was involved in magma genesis. The thus recycled continental material was heterogeneous with respect to its primary ages and/or metamorphic history; the approximate minimum ages of the continental sources range from 350 to 590 m.y. The 101+-2 m.y. old Transhimalaya granodiorite, which intrudes a series of mainly basaltic island arc rocks (Dras Series) shows that this island arc was attached to the continental margin at that times. This is consistent with the hypothesis that the ''Ladakh Tethys'' closed through two subduction regimes: (1) an early Cretaceous subduction, which formed the Dras island arc, and (2) a late Cretaceous to Palaeocene subduction at the continental margin, which caused the emplacement of the Transhimalaya plutonic belt. (orig.)

River Valley pluton, Ontario - A late-Archean/early-Proterozoic anorthositic intrusion in the Grenville Province

Science.gov (United States)

Ashwal, Lewis D.; Wooden, Joseph L.

1989-01-01

This paper presents Nd, Sr, and Pb isotopic data indicating a late-Archean/early-Proterozoic age for the River Valley anorthositic pluton of the southwestern Grenville Province of Sudbury, Ontario. Pb-Pb isotopic data on 10 whole-rock samples ranging in composition from anorthosite to gabbro yield an age of 2560 + or - 155 Ma. The River Valley pluton is thus the oldest anorthositic intrusive yet recognized within the Grenville Province. The Sm-Nd isotopic system records an age of 2377 + or - 68 Ma. High Pb-208/Pb-204 of deformed samples relative to igneous-textured rocks implies Th introduction and/or U loss during metamorphism in the River Valley area. Rb-Sr data from igneous-textured and deformed samples and from mineral separates give an age of 2185 + or - 105 Ma, indicating substantial disturbance of the Rb-Sr isotopic system.

Ginga com tapioca: gastronomia do mercado da Redinha como atrativo turístico

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Charllys de Oliveira Lima

2016-06-01

Full Text Available O presente estudo tem como objetivo analisar o Mercado da Redinha enquanto potencial turístico gastronômico, através da comercialização da ginga com tapioca, um prato típico da cidade de Natal. Apesar de também ser comercializado por vendedores ambulantes nas principais praias do litoral natalense, o Mercado Público da Redinha é o ponto original onde se comercializa esse prato. Muitos turistas que visitam a capital potiguar desejam conhecer a gastronomia típica, mas o mercado atrai especialmente turistas locais e moradores como opção de entretenimento. Realizou-se um estudo de natureza quantitativa descritiva, cujos dados foram obtidos através de formulário composto por 15 questões respondidas por 31 usuários do Mercado. Para análise, as questões foram organizadas em categorias que abrangeram o perfil dos usuários e suas opiniões em relação à infraestrutura do mercado, à frequência de visitação, meio de divulgação que os levou a conhecer o Mercado, percepção sobre qualidade de acesso e demandas de melhorias. Em relação à gastronomia, indagou-se sobre o cardápio servido, o gosto e apresentação do prato, o valor cobrado e a opinião sobre a qualidade do atendimento. Os resultados evidenciaram pontos negativos como a falta de saneamento adequado e regular que também comprometia a higiene; bem como a falta de infraestrutura como principal reclamação entre os entrevistados. Em relação aos pontos positivos foram incluídos: preço justo, bom atendimento e gosto agradável do prato. A maioria dos entrevistados indicaria o mercado a outros e, apesar dos diversos problemas apontados, os usuários, especialmente, do sexo masculino, são atraídos em busca da ginga com tapioca para beber com amigos na semana. A revisão da dinâmica interna do Mercado pode fomentar como estratégia para incluí-lo no roteiro do turismo gastronômico regional.

Las mujeres en el mercado laboral en perspectiva europea

OpenAIRE

Moltó Carbonell, María Luisa

1998-01-01

En este artículo se analiza la situación de las mujeres en el mercado laboral europeo, utilizando la base de datos de Eurostat New Cronos. Dicha situación responde a la evolución de tres tipos de factores: la voluntad y capacidad de las mujeres para participar en el mercado laboral, los relacionados con la demanda de trabajo y las políticas de empleo. Esta exposición se centra, por tanto, en la participación femenina, la ocupación, el desempleo, las formas de empleo atípicas y las diferencias...

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

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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.

Groundwater Chemistry and Overpressure Evidences in Cerro Prieto Geothermal Field

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Ivan Morales-Arredondo

2017-01-01

Full Text Available In order to understand the geological and hydrogeological processes influencing the hydrogeochemical behavior of the Cerro Prieto Geothermal Field (CP aquifer, Mexico, a characterization of the water samples collected from geothermal wells was carried out. Different hydrochemical diagrams were used to evaluate brine evolution of the aquifer. To determine pressure conditions at depth, a calculation was performed using hydrostatic and lithostatic properties from CP, considering geological characteristics of the study area, and theoretical information about some basin environments. Groundwater shows hydrogeochemical and geological evidences of the diagenetic evolution that indicate overpressure conditions. Some physical, chemical, textural, and mineralogical properties reported in the lithological column from CP are explained understanding the evolutionary process of the sedimentary material that composes the aquifer.

Estrategia de cobertura a través de contratos a plazo en mercados eléctricos.

OpenAIRE

Trespalacios Carrasquilla, Alfredo; Rendón García, Juan Fernando; Pantoja, Javier

2012-01-01

Quienes transan electricidad en los mercados liberalizados, están expuestos a riesgos que requieren un análisis y tratamiento diferente al de otro tipo de productos básicos (commodities). La dinámica del precio actual del mercado (spot), unida a la necesidad de completar el mercado cubriendo la exposición al riesgo de volumen son, entre otras, las características que hacen a este mercado diferente y complejo. Nuestro trabajo muestra un esquema de cobertura estática que puede implementar un ag...

A tale of 10 plutons - Revisited: Age of granitic rocks in the White Mountains, California and Nevada

Science.gov (United States)

McKee, E.H.; Conrad, J.E.

1996-01-01

40Ar/39Ar incremental heating analysis and conventional K-Ar age determinations on plutonic rocks of the White Mountains define two stages of magmatic emplacement: Late Cretaceous, between ca. 90 Ma and 75 Ma, and Middle-Late Jurassic, between ca. 180 and 140 Ma. The Jurassic stage can be divided into two substages, 180-165 Ma and 150-140 Ma. Thermal effects of the younger plutons on the older granitoids partially to completely reset ages, making it difficult to determine the age of emplacement and cooling of several of the plutons even by 40Ar/39Ar incremental heating analyses. New data together with published ages and regional geochronological synthesis of the Sierra Nevada batholith indicate that regions within the batholith have coherent periods or episodes of magmatic activity. In the White Mountains and Sierra Nevada directly to the west there was little or no activity in Early Jurassic and Early Cretaceous time; magmatism took place during relatively short intervals of 15 m.y. or less in the Middle and Late Jurassic and Late Cretaceous periods. The new K-Ar and 40Ar/39Ar analyses of granitoids from the White Mountains help, but do not completely clarify the complex history of emplacement, cooling, and reheating of the batholith.

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

International Nuclear Information System (INIS)

Fraenkel, M.O.

1974-01-01

The Cerro Partido residual basin is a shallow (85 meters) and small (25km 2 ) 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 + U 3 O 8 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

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)

Coronel, N.

1987-01-01

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.

A GEOGRAFIA DO MERCADO MUNDIAL DE PRODUTOS AGROALIMENTARES E O PAPEL DO BRASIL

OpenAIRE

Medeiros, Marlon Clovis

2014-01-01

O artigo analisa as mudanças recentes na geografia do mercado mundial de produtos agrícolas, discutindo a inserção do Brasil, o papel dos mercados futuros na elevação dos preços internacionais e as mudanças entre os países exportadores e importadores de produtos agrícolas. Argumentamos que a principal mudança no espaço agrícola mundial nas últimas duas décadas foi o crescimento dos investimentos financeiros em commodities agrícolas e o crescimento dos mercados de futuros. A dinâmica financeir...

Gestión de mercado basada en la eficiencia de los procesos de aprendizaje

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Ma. Cruz Lozano Ramírez

2016-06-01

Full Text Available Este documento presenta los resultados de un estudio cuyo objetivo fue identificar la gestión de mercado basada en la eficiencia de la implementación de procesos de aprendizaje en el contexto de estrategias de mercado. El diseño de investigación fue no experimental, correlacional, aplicado a 21 sujetos con funciones dirección en organizaciones de los sectores comercio y servicios. Los resultados de las pruebas explican que la eficiencia de la gestión de mercado está determinada por los procesos de aprendizaje relativos al diseño de estrategias que abordan la ampliación del mercado con servicios especializados e incremento en clientes, beneficios e innovación de productos, programas de promoción y diferenciación de precios.

Estudio de Mercado de la Microencapsulación de Fluidos

OpenAIRE

de Batlle Mercadé, Juan Batlle

2016-01-01

El TFG desarrollado a continuación trata sobre un estudio de mercado de la microencapsulación de fluidos llevado a cabo por petición de una empresa especializada en este producto. Los objetivos de este proyecto son: en primer lugar, dimensionar el mercado de las micropartículas para las zonas geográficas de Europa (EU) y Estados Unidos (EEUU) en cuatro sectores (Pharma, Functional Food, Personal Care y Home Care); en segundo lugar, identificar la demanda no cubierta mediante las necesidades d...

Geochemical Relationships between Volcanic and Plutonic Upper to Mid Crustal Exposures of the Rosario Segment, Alisitos Arc (Baja California, Mexico): An Outstanding Field Analog to the Izu-Bonin-Mariana Arc

Science.gov (United States)

Morris, R.; DeBari, S. M.; Busby, C. J.; Medynski, S.

2015-12-01

Exposed paleo-arcs, such as the Rosario segment of the Cretaceous Alisitos Arc in Baja California, Mexico, provide an opportunity to explore the evolution of arc crust through time. Remarkable 3-D exposures of the Rosario segment record crustal generation processes in the volcanic rocks and underlying plutonic rocks. In this study, we explore the physical and geochemical connection between the plutonic and volcanic sections of the extensional Alisitos Arc, and elucidate differentiation processes responsible for generating them. These results provide an outstanding analog for extensional active arc systems, such as the Izu-Bonin-Mariana (IBM) Arc. Upper crustal volcanic rocks have a coherent stratigraphy that is 3-5 km thick and ranges in composition from basalt to dacite. The most felsic compositions (70.9% SiO2) are from a welded ignimbrite unit. The most mafic compositions (51.5% SiO2, 3.2% MgO) are found in basaltic sill-like units. Phenocrysts in the volcanic units include plagioclase +/- amphibole and clinopyroxene. The transition to deeper plutonic rocks is clearly an intrusive boundary, where plutonic units intrude the volcanic units. Plutonic rocks are dominantly a quartz diorite main phase with a more mafic, gabbroic margin. A transitional zone is observed along the contact between the plutonic and volcanic rocks, where volcanics have coarsely recrystallized textures. Mineral assemblages in the plutonic units include plagioclase +/- quartz, biotite, amphibole, clinopyroxene and orthopyroxene. Most, but not all, samples are low K. REE patterns are relatively flat with limited enrichment. Normalization diagrams show LILE enrichment and HFSE depletion, where trends are similar to average IBM values. We interpret plutonic and volcanic units to have similar geochemical relationships, where liquid lines of descent show the evolution of least to most evolved magma types. We provide a model for the formation and magmatic evolution of the Alisitos Arc.

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)

Perrin, J.

1983-01-01

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

Discordant K-Ar ages between hornblende and biotite from the Tanzawa tonalitic pluton in the southern Fossa Magna, central Japan

International Nuclear Information System (INIS)

Sato, Kohei; Shibata, Ken; Uchiumi, Shigeru

1986-01-01

K-Ar ages were determined for hornblende and biotite in three tonalites from the Tanzawa pluton in the southern Fossa Magna, central Japan. The two minerals show discordant ages of 10.1 and 10.7 Ma for hornblende and 4.6 - 5.1 Ma for biotite. The age data and field evidence indicate that the pluton was emplaced in the Tanzawa Group in Middle Miocene time and its slow cooling (ca. 50 deg C/Ma in average) resulted in younger ages of boitites than hornblendes due to lower closure temperature for biotite. (author)

Volumen y asimetría en los principales mercados accionarios latinoamericanos

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Werner Kristjanpoller

2012-01-01

Full Text Available El presente estudio se enfoca en determinar la relación entre los volúmenes de operación y la asimetría de los rendimientos de los principales mercados accionarios latinoamericanos: Argentina, Brasil, Chile, Colombia, México y Perú. Se utiliza el modelo propuesto por Hutson et al. (2008, el cual incluye especificaciones de los primeros tres momentos de los volúmenes de operación comercializados y de los rendimientos de los mercados. La principal conclusión del estudio es el hallazgo de evidencia estadísticamente significativa de la influencia de los volúmenes de transacción y la asimetría de los rendimientos en los mercados accionarios de México, Brasil, Chile, Colombia y Argentina y en menor cuantía en Perú.

Propuestas de mejora al mercado de energía mayorista para asegurar la confiabilidad del Sistema Interconectado Nacional

OpenAIRE

Castillo Marín, Jaime Alonso

2016-01-01

Las fallas de mercado justifican la regulación en los mismos y dadas las características del sector eléctrico se han realizado diseños de mercados en búsqueda de una asignación eficiente de los recursos -- Este diseño para el Mercado de Energía Mayorista en Colombia se ha mantenido en esencia igual desde sus inicios, a excepción de la creación del mercado de confiabilidad desarrollado posteriormente -- Ante periodos de escasez en la oferta, en el Mercado de Energía Mayorista se ha visto la ne...

Caracterización del mercado accionario colombiano, 2001-2006: un análisis comparativo

OpenAIRE

Jorge Mario Uribe Gil

2007-01-01

Partiendo de la base teórica de que existe una relación positiva entre el desarrollo del mercado de capitales y el crecimiento económico, se construyen indicadores de tamaño, liquidez, riesgo, integración y eficiencia, para el mercado accionario colombiano. Para esto, se usan medidas tradicionales de profundidad del mercado, además de modelos GARCH, estimadores de razones de varianzas heteroscedásticamente robustos y asintóticamente consistentes e indicadores de integración internacional basa...

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

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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.

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)

Benitez, A.F.; Fuente, A.; Maloberti, A.; Landi, V.A.; Bianchi, R.E.; Marveggio de Bianchi, N.; Gayone, M.R.

1993-01-01

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)

Fraude e branqueamento de capitais no mercado da droga

OpenAIRE

Amaro, Andreia Ramos

2017-01-01

Versão final (Esta versão contém as críticas e sugestões dos elementos do júri) Ao longo das últimas décadas e com a crescente globalização, os infratores têm adotado novos e sofisticados métodos de ocultação de capitais ilícitos, nomeadamente, provenientes da droga. Perante isto, o presente trabalho foca-se na temática do branqueamento de capitais e da fraude no mercado da droga, sendo o seu grande objetivo o estudo da relação entre branqueamento de capitais, fraude e o mercado da drog...

Custo de capital e globalização dos mercados

OpenAIRE

Oliveira, Reinaldo Grasson de

2010-01-01

O trabalho aborda a questão do custo de capital em um contexto de mercados globalizados. Analisa as principais metodologias para definição das variáveis que compõem o Custo Médio Ponderado de Capital (Weighted Average Cost of Capital) e o impacto exercido pela segmentação/integração dos mercados financeiros mundiais nesta definição. Discute as relações internacionais de paridade (Purchasing Power Parity, Efeito Fisher, lnterest Rate Parity, entre outras) e suas implicações p...

The chemical and isotopic differentiation of an epizonal magma body: Organ Needle pluton, New Mexico

Science.gov (United States)

Verplanck, P.L.; Farmer, G.L.; McCurry, M.; Mertzman, S.A.

1999-01-01

Major and trace element, and Nd and Sr isotopic compositions of whole rocks and mineral separates from the Oligocene, alkaline Organ Needle pluton (ONP), southern New Mexico, constrain models for the differentiation of the magma body parental to this compositionally zoned and layered epizonal intrusive body. The data reveal that the pluton is rimmed by lower ??(Nd) (~-5) and higher 87Sr/86Sr (~0.7085) syenitic rocks than those in its interior (??(Nd) ~ 2, 87Sr/86Sr ~0.7060) and that the bulk compositions of the marginal rocks become more felsic with decreasing structural depth. At the deepest exposed levels of the pluton, the ??(Nd)~-5 lithology is a compositionally heterogeneous inequigranular syenite. Modal, compositional and isotopic data from separates of rare earth element (REE)-bearing major and accesory mineral phases (hornblende, titanite, apatite, zircon) demonstrate that this decoupling of trace and major elements in the inequigranular syenite results from accumulation of light REE (LREE)-bearing minerals that were evidently separated from silicic magmas as the latter rose along the sides of the magma chamber. Chemical and isotopic data for microgranular mafic enclaves, as well as for restite xenoliths of Precambrian granite wall rock, indicate that the isotopic distinction between the marginal and interior facies of the ONP probably reflects assimilation of the wall rock by ??(Nd) ~-2 mafic magmas near the base of the magma system. Fractional crystallization and crystal liquid separation of the crystally contaminated magma at the base and along the margins of the chamber generated the highly silicic magmas that ultimately pooled at the chamber top.

Geochemistry of mylonitic tourmaline-bearing granite- gneiss pluton in the northeast of June mine

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Arezoo Moradi

2017-07-01

Full Text Available Introduction Studied mylonitic granite-gneiss body is located in the Northwest of the Azna region in the Lorestan province close to the June dimension stone mine. It is a part of the metamorphic- magmatic complex including granite-gneiss, amphibolite, marble and schist. The crystalline basement is attributed to late-Neoproterozoic and it indicates a Panafrican basement, which yields a laser-ablation ICP–MS U–Pb zircon ages of 608 ± 18 Ma and 588 ± 41 Ma (Shakerardakani et al., 2015. There are two granite-gneiss plutons in the complex that are Galeh– Dezh (Shabanian et al., 2009, and June plutons. The Galeh-Doz pluton are previously proposed as syn-deformation pluton with a major S-shaped bend which has been imparted during dextral shearing with a Late Cretaceous (Mohajjel and Fergusson, 2000. However, new age dating on the pluton using U–Pb in the magmatic zircon produced the late-Neoproterozoic dates (Nutman et al., 2014; Shakerardakani et al., 2015. The granite-gneiss plutons show mylonitic fabrics and microstructures (Shabanian et al., 2010. The geochemical characteristics of mylonitic granite-gneiss body near June mine in NW Azna, is in the focus of our research. Materials and methods Petrographic investigations of 30 thin sections were made. Then eight samples were selected and analyzed for whole rock major, trace and REE compositions by ICP-emission spectrometry and ICP-mass spectrometry using natural rock standards as reference samples for calibration at the ACME Analytical Laboratories in Vancouver, British Columbia, Canada. Results The studied gneiss- granitic body has lepido-granoblastic texture as its major texture. It variably shows evidence of dynamic deformation from ultramylonite to protomylonite. The gneiss- granite consists of quartz, alkali feldspar (mostly as perthite, plagioclase, biotite, white mica (muscovite and phengitic muscovite. Accessory phases in the granitoid include, tourmaline, zircon, magmatic epidote

Ion-adsorption REEs in regolith of the Liberty Hill pluton, South Carolina, USA: An effect of hydrothermal alteration

Science.gov (United States)

Bern, Carleton R.; Yesavage, Tiffany; Foley, Nora K.

2017-01-01

Ion-adsorbed rare earth element (REE) deposits supply the majority of world heavy REE production and substantial light REE production, but relatively little is known of their occurrence outside Southeast Asia. We examined the distribution and forms of REEs on a North American pluton located in the highly weathered and slowly eroding South Carolina Piedmont. The Hercynian Liberty Hill pluton experiences a modern climate that includes ~ 1500 mm annual rainfall and a mean annual temperature of 17 °C. The pluton is medium- to coarse-grained biotite-amphibole granite with minor biotite granite facies. REE-bearing phases are diverse and include monazite, zircon, titanite, allanite, apatite and bastnäsite. Weathered profiles were sampled up to 7 m-deep across the ~ 400 km2 pluton. In one profile, ion-adsorbed REEs plus yttrium (REE + Y) ranged up to 581 mg/kg and accounted for up to 77% of total REE + Y in saprolite. In other profiles, ion-adsorbed REE + Y ranged 12–194 mg/kg and only accounted for 3–37% of totals. The profile most enriched in ion-adsorbed REEs was located along the mapped boundary of two granite facies and contained trioctahedral smectite in the saprolite, evidence suggestive of hydrothermal alteration of biotite at that location. Post-emplacement deuteric alteration can generate easily weathered REE phases, particularly fluorocarbonates. In the case of Liberty Hill, hydrothermal alteration may have converted less soluble to more soluble REE minerals. Additionally, regolith P content was inversely correlated with the fraction ion-adsorbed REEs, and weathering related secondary REE-phosphates were found in some regolith profiles. Both patterns illustrate how low P content aids in the accumulation of ion-adsorbed REEs. The localized occurrence at Liberty Hill sheds light on conditions and processes that generate ion-adsorbed REEs.

Padronização das taxas de juros nos investimentos realizados no mercado financeiro

OpenAIRE

Galhano Junior, Geraldo Prado

1983-01-01

Visando eliminar a confusão entre os investidores e padronizar um procedimento das instituições financeiras, propõe-se que todos os investimentos do mercado financeira sejam feitos através de um único modelo de juros. Dentre os modelos de juros existentes no mercado, foi adotado o modelo de juros compostos, para ser efetuada a padronização. A escolha do modelo de juros composto se deve as suas características, que melhor representam a realidade do nosso mercado financeiro, como teremos oportu...

Dimensiones simbólicas de las prácticas de intercambio en mercados de Buenos Aires y Viena.

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Tihomir Viderman

2014-12-01

Full Text Available Este artículo explora dos mercados en dos continentes diferentes, el “Mercado Solidario Bonpland” en Buenos Aires (Argentina y el “Mercado de los agricultores del centro socio-cultural WUK” en Viena (Austria, con el propósito de indagar en las dimensiones simbólicas de las prácticas de la vida cotidiana, que se desarrollan en estos mercados. La particularidad es que estos mercados fueron originados y sostenidos por grupos de activistas locales para promover y apoyar la participación y el intercambio social. Aunque estos dos mercados difieren en su apariencia, los significados y las ideas conceptuales detrás de cada uno, reflejan propuestas similares hacia la consolidación de prácticas culturales alternativas, lo que conduce a que los mercados se tornen como lugares de intercambio y encuentro social relevantes para la comunidad local. En el artículo se abordan las “prácticas de intercambio” halladas en los mercados como acciones estratégicas que permiten obtener un medio de vida y un espacio de pertenencia social. Los actores involucrados en la producción de los mercados analizados, muestran a la performatividad como una faceta esencial de la producción de significados simbólicos, con la capacidad de generar un espacio para el fomento y desarrollo de posibles prácticas emancipatorias.

Rb-Sr isochronous age of Vepor pluton granitoids

International Nuclear Information System (INIS)

Bagdasaryan, G.P.; Gykasyan, R.Kh.; Cambel, B.

1986-01-01

The result are presented of geochronological investigations of the Vepor pluton granitoids by the Rb-Sr isochronous method. The results prove the Variscan age of granodiorite magmatism of the Sihla type (387±27 m.y.) and the Early Variscan age of leucocratic granitoids of the Vepor and the Ipel types (284±22 m.y.). Since the initial ratio of 87 Sr/ 86 Sr in granitoids of the Sihla type is 0.7054 and of the Vepor type 0.7060, it can be assumed that during the formation of the granitoids of veporides there was an increased supply of matter from the main source affecting genesis of granitoids. The results prove a polyphase character of the Variscan granitoids of Veporicum. (author)

El Mercado Integrado Latinoamericano (MILA: sus expectativas y el impacto del latibex

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Jorge Armando Ortegón Rojas

2017-02-01

Full Text Available Los objetivos principales de este trabajo son: primero, evaluar el grado en que el comportamiento del Mercado de Valores Latinoamericanos en Euros, Latibex, explica el comportamiento del Mercado Integrado Latinoamericano, MILA, y los mercados accionarios de Colombia, Chile y Perú bajo el supuesto de que por transarse valores latinoamericanos en ambas plazas debe existir relación alguna en el comportamiento de sus í­ndices bursátiles. Esto se logra mediante un análisis de correlación lineal, exponencial y logarí­tmica. Segundo, conocer el comportamiento desde el año 2009 de los mercados accionarios mencionados recientemente, y su posible tendencia a corto plazo. Esto se logra mediante un análisis de regresión lineal, exponencial, logarí­tmica y cuadrática. Lo anterior arrojó que el comportamiento del MILA es explicado en un 90,6 % por el Latibex. Adicionalmente, analizado cada í­ndice bursátil como serie de tiempo, se observa que tienen un comportamiento decreciente en general a partir del año 2012, y con una tendencia a continuar decreciendo a corto plazo.

A PARTICIPAÇÃO DO EMPREENDEDOR QUIXADAENSE NO MERCADO DE CAPITAIS

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Benedito Almeida Sodré

2017-08-01

Full Text Available O Brasil, desde seu descobrimento, teve várias fases no seu desenvolvimento econômico, desde o colonialismo até a atual globalização. Durante estes períodos, sua econômia sofreu várias transformações até chegar a era da industrialização e da tecnologia. Para que estas transformações fossem realizadas foram necessários grandes investimentos, tanto por parte do governo quanto por parte do capital privado das grandes empresas. Para que tais investimentos existissem, se faz necessário uma fonte de recursos que é o mercado de capitais. Este estudo tem como objetivo identificar a participação do investidor quixadaense no referido mercado, bem como seu conhecimento sobre esse mercado e a BM&FBOVESPA (Bolsa de Valores de São Paulo. Para o cumprimento deste estudo foi realizada uma pesquisa de survey, de natureza quantitativa. A coleta de dados ocorreu com aplicação de questionário auto-administrado com perguntas fechadas, de escala Likert de cinco pontos. A pesquisa ocorreu no município de Quixadá – CE, com uma amostra de 15 dos empresários de destaque no setor de indústria e comércio local. Os dados colhidos foram avaliados no Software Excel 2013, e depois de analisados e comentados concluiu-se que a participação do empreendedor quixadaense no mercado de capitais é insignificante com o potencial da indústria e comércio local, bem como o conhecimento dos empreendedores sobre o referido mercado e a BM&FBOVESPA. Para incentivar e melhorar essa participação, seria necessário que fossem efetuados mais divulgações e orientações sobre o tema para melhor esclarecer aos empreendedores.

Experimental and petrological constraints on long-term magma dynamics and post-climactic eruptions at the Cerro Galán caldera system, NW Argentina

Science.gov (United States)

Grocke, Stephanie B.; Andrews, Benjamin J.; de Silva, Shanaka L.

2017-11-01

Cerro Galán in NW Argentina records > 3.5 Myr of magmatic evolution of a major resurgent caldera complex. Beginning at 5.72 Ma, nine rhyodacitic ignimbrites (68-71 wt% SiO2) with a combined minimum volume of > 1200 km3 (Dense Rock Equivalent; DRE) have been erupted. The youngest of those ignimbrites is the eponymous, geochemically homogenous, caldera-forming 2.08 ± 0.02 Ma Cerro Galán Ignimbrite (CGI; > 630 km3 DRE). Following this climactic supereruption, structural and magmatic resurgence led to the formation of a resurgent dome and post-climactic lava domes and their associated pyroclastic deposits. A clear transition from amphibole to sanidine-bearing magmas occurred during the evolution of Cerro Galán and is inferred to represent a shallowing of the magma system. We test this hypothesis here using experimental phase equilibria. We conducted a series of phase equilibria experiments on the post-climactic dome lithologies under H2O-saturated conditions using cold seal Waspaloy pressure vessels with an intrinsic log fO2 of NNO + 1 ± 0.5 across a temperature-pressure range of 750-900 °C and 50-200 MPa (PH2O = Ptotal), respectively. Petrologic and geochemical analysis of the post-climactic lithologies shows that the natural phase assemblage (plagioclase + quartz + biotite + sanidine + Fe-Ti oxides ± apatite ± zircon) is stable at history of Cerro Galán is informed through a detailed investigation of the textural differences among the post-climactic dome lithologies, and a comparison of those textures with previously published decompression experiments. These suggest that the highly vesiculated, pumiceous clasts with rare microlites represent magma stored within the core of the lava dome that decompressed relatively rapidly (0.003-0.0003 MPa s-1) and evolved via closed system degassing. Resulting over-pressure of the dome may have triggered superficial explosion. In contrast, dense clasts with abundant crystalline silica precipitates represent more typical

[Discussion on diagenesis of Xilingang pluton-constrained by X-ray Fluorescence spectroscopy, plasma mass spectrometry and Raman spectroscopy].

Science.gov (United States)

Tang, Yu-Kun; Chen, Guo-Neng; Zhang, Ke; Huang, Hai-Hua

2013-05-01

The results on Xilingang pluton, mainly consisting of red beds, granites containing numerous debris of red beds and granites, obtained by X-ray fluorescence spectroscopy, plasma mass spectrometry and Raman spectroscopy show: (1) Xilingang pluton from red beds, granites containing numerous debris of red beds to granites has obvious characteristics of decreasing silicon and alkali content, and rising ignition loss, dark mineral content and oxidation index; (2) Chondrite-normalized REE distribution curves and primitive mantle-normalized spider diagram for trace elements of redbed, granites containing numerous debris of red beds and granites have a good consistency, the distribution characteristics of elements are similar to Nanling transformation-type granite; (3) The value of Raman spectrogram characteristic peak of quartz crystal in Xilingang granite decreased from the center of quartz crystal, and FWHM is steady. According to the above, the authors believe that Xilingang granite formed was related to in-situ melting of red beds and underlying strata and magma consolidation. Volatile components were discharged continuously, and oxidation index decreased gradually in the melting process. In the process of diagenesis, the top of pluton tend to be an ongoing silicon and alkali increase, while TFeO and MgO continue to migrate to bottom, and crystallization environment is a relatively closed and steady system.

The link between volcanism and plutonism in epizonal magma systems; high-precision U–Pb zircon geochronology from the Organ Mountains caldera and batholith, New Mexico

Science.gov (United States)

Rioux, Matthew; Farmer, Lang; Bowring, Samuel; Wooton, Kathleen M.; Amato, Jeffrey M.; Coleman, Drew S.; Verplanck, Philip L.

2016-01-01

The Organ Mountains caldera and batholith expose the volcanic and epizonal plutonic record of an Eocene caldera complex. The caldera and batholith are well exposed, and extensive previous mapping and geochemical analyses have suggested a clear link between the volcanic and plutonic sections, making this an ideal location to study magmatic processes associated with caldera volcanism. Here we present high-precision thermal ionization mass spectrometry U–Pb zircon dates from throughout the caldera and batholith, and use these dates to test and improve existing petrogenetic models. The new dates indicate that Eocene volcanic and plutonic rocks in the Organ Mountains formed from ~44 to 34 Ma. The three largest caldera-related tuff units yielded weighted mean 206Pb/238U dates of 36.441 ± 0.020 Ma (Cueva Tuff), 36.259 ± 0.016 Ma (Achenback Park tuff), and 36.215 ± 0.016 Ma (Squaw Mountain tuff). An alkali feldspar granite, which is chemically similar to the erupted tuffs, yielded a synchronous weighted mean 206Pb/238U date of 36.259 ± 0.021 Ma. Weighted mean 206Pb/238U dates from the larger volume syenitic phase of the underlying Organ Needle pluton range from 36.130 ± 0.031 to 36.071 ± 0.012 Ma, and the youngest sample is 144 ± 20 to 188 ± 20 ka younger than the Squaw Mountain and Achenback Park tuffs, respectively. Younger plutonism in the batholith continued through at least 34.051 ± 0.029 Ma. We propose that the Achenback Park tuff, Squaw Mountain tuff, alkali feldspar granite and Organ Needle pluton formed from a single, long-lived magma chamber/mush zone. Early silicic magmas generated by partial melting of the lower crust rose to form an epizonal magma chamber. Underplating of the resulting mush zone led to partial melting and generation of a high-silica alkali feldspar granite cap, which erupted to form the tuffs. The deeper parts of the chamber underwent continued recharge and crystallization for 144 ± 20 ka after the

Mercados e racionalidades: a perspectiva de Alberto Guerreiro Ramos e Cornelius Castoriadis

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Manoel Fernandes Nery

Full Text Available Mercados e racionalidades são duas categorias das Ciências Sociais bastante discutidas na academia. Considera-se Max Weber um dos pioneiros no estudo da categoria racionalidades, da qual teria se originado grande parte das interpretações dominantes nas Ciências Sociais, em particular da Sociologia. Os autores que descrevem o mercado enfatizam diferentes aspectos, e os relatos sobre seu aparecimento histórico são também divergentes. Não existe, portanto, nas Ciências Sociais, uma interpretação única sobre as funções e a historicidade do mercado, bem como não há unanimidade em relação às formas de racionalidades dominantes. Este ensaio teórico traz a perspectiva de dois autores sobre mercados e racionalidades, sem a intenção de absolutizar seu pensamento ou limitar suas contribuições aos temas. Ramos (1981 concebe a razão como uma força inerente ao indivíduo, a qual denomina razão substantiva, assinalando que, com Thomas Hobbes, a razão configura um cálculo utilitário de consequências. Adicionalmente, Ramos (1981 vê o mercado como uma ameaça à liberdade e autonomia dos indivíduos. Para Castoriadis (1992b, 1996, 1999b, a razão está presente em um coletivo social anônimo, sendo homem e sociedade inseparáveis do contexto sócio-histórico. Já o mercado, bem ou mal, funciona, apesar da manipulação dos consumidores e da violência contra os trabalhadores. Em comum, os autores defendem a liberdade e a autonomia dos indivíduos. Conclui-se o ensaio corroborando a visão de Alves (2007, pois as elucidações apresentadas ao longo do texto indicam que as divergências não estão nas teorias e nos métodos, mas na natureza do objeto estudado.

Estrategia de Cobertura a Través de Contratos Forward en Mercados Eléctricos

OpenAIRE

Trespalacios Carrasquilla, Alfredo; Rendón García, Juan Fernando; Pantoja Robayo, Javier Orlando

2012-01-01

Quienes transan electricidad en los mercados liberalizados, est an ex- puestos a riesgos que requieren un an alisis y tratamiento diferente al de otro tipo de commodities. La din amica del precio spot, unida a la necesi- dad de completar el mercado cubriendo la exposici on al riesgo de volumen, son entre otras las caracter sticas que hacen a este mercado diferente y complejo. Nuestro trabajo presenta un esquema de cobertura est atica que puede implementar un agente que busc...

ESTUDIO PRELIMINAR DE LA FAUNA AMPHIBIA EN EL CERRO MURRUCUCÚ, PARQUE NATURAL NACIONAL PARAMILLO Y ZONA AMORTIGUADORA, TIERRALTA, CÓRDOBA, COLOMBIA

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ROMERO-MARTÍNEZ HERÓN JOSÉ

2008-07-01

Full Text Available Con el objetivo de estudiar la fauna anfibia en el Cerro Murrucucú (PNN Paramillo,Tierralta, Córdoba, se realizaron muestreos durante los meses de diciembre de2004, enero y febrero de 2005 en diferentes localidades; se utilizaron dos estrategiasde muestreo (búsqueda libre por inspección visual y trampas de caída. En primerainstancia se comparó la riqueza y la abundancia de las especies en tres zonasaltitudinales en uno de los sectores mejor conservados del Cerro. Se encontró queen la parte baja y media predominan las especies de la familia Hylidae, mientras queen la parte alta predominan representantes de la familia Brachycephalidae, en sumayoría especies del género Eleutherodactylus. Se registran 52 especies para el CerroMurrucucú, que representan el 8% del total de especies en Colombia y más del 80% delas documentadas para el Departamento de Córdoba; las cuales están agrupadas en dosórdenes, 10 familias y 26 géneros. Las familias más representativas, Brachycephalidaee Hylidae, concentran un poco más del 50% de las especies. También se registraronpor primera vez 18 especies para el Departamento de Córdoba y se amplia el rangode distribución geográfico de 18 especies y altitudinal de siete de estas. Se tiene elprimer registro de Eleutherodactylus cruentus para Colombia y el primero de E. viejaspara la Cordillera Occidental Colombiana

La diversificación de los mercados como estrategia de la agricultura familiar

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Clara Craviotti

2013-01-01

Full Text Available Partiendo de distintos abordajes teóricos sobre los mercados, el artículo analiza las formas de comercialización de los fruticultores familiares del noreste de la provincia de Buenos Aires (Argentina. El área reviste particular interés por conformar un sistema productivo local que experimenta desde hace varios años un proceso de retracción, en contraposición a la expansión del cultivo de la soja orientada a los mercados mundiales. El análisis considera el contenido de los vínculos establecidos y la composición de los capitales como condicionantes de la inserción en los mercados, y visualiza a éstos como ámbitos de interacción social donde se construyen nuevas relaciones. Argumenta que en los productores familiares la diversificación de canales comerciales refuerza a la encontrada en el plano productivo, y que los circuitos dominados por grandes empresas y los mercados locales no constituyen alternativas mutuamente excluyentes para este tipo de productores sino complementarias.

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.

Paracas Cultural Readaptation To The Nasca Entity: An Approach From The Settlement Of Cerro Cordova

OpenAIRE

Llanos Jacinto, Oscar Daniel

2017-01-01

Except rare exceptions, the Paracas society of the Ica valley has been extensively studied from decontextualized materials, including pottery collected from clandestine tomb excavations in the Ocucaje basin. From the stylistic analysis of these pieces, which also included Nasca specimens, the hypothesis was elaborated that assumed the birth from the Paracas, expressed in the well-known axiom «transition paracas-nasca». The works carried out in Cerro Córdova and those that since 2009 are carri...

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

International Nuclear Information System (INIS)

Goso, H.

1978-01-01

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

Estrategia de cobertura con productos derivados para el mercado energético colombiano

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Jhon Alexis Díaz Contreras

2014-01-01

Full Text Available El desarrollo que ha presentado el mercado mayorista de energía en Colombia ha permitido que hoy en día se estén negociando futuros de electricidad en el mercado de capitales local. Este trabajo tiene como objetivo diseñar un producto derivado en el que subyace el precio de la electricidad. Para esto, se analiza la serie de tiempo del precio de la electricidad para modelar su volatilidad; y a partir de esta, se diseña una opción exótica tipo barrera que muestra cómo se pueden usar este tipo de productos financieros en la cobertura de riesgos de los agentes del mercado.

Estrategia de cobertura con productos derivados para el mercado energético colombiano

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Jhon Alexis Díaz Contreras

2014-01-01

Full Text Available El desarrollo que ha presentado el mercado mayorista de energía en Colombia ha permitido que hoy en día se estén negociando futuros de electricidad en el mercado de capitales local. Este trabajo tiene como objetivo dise ̃ nar un producto derivado en el que subyace el precio de la electricidad. Para esto, se analiza la serie de tiempo del precio de la electricidad para modelar su volatilidad ; y a partir de esta, se dise ̃ na una opción exótica tipo barrera que muestra cómo se pueden usar este tipo de productos financieros en la cobertura de riesgos de los agentes del mercado.

Prêmio de liquidez de ações : um estudo para o mercado brasileiro

OpenAIRE

Chiara, Marco

2014-01-01

Existe uma divergência nos estudos de mercados emergentes sobre a relação entre retorno e liquidez. Enquanto nos mercados desenvolvidos é consenso que o retorno cresce com a falta de liquidez, em mercados como o Brasil concorda-se com a sua influência, mas não é unânime o crescimento da rentabilidade diante da iliquidez. Assim, este estudo busca definir as variáveis que representam o conceito de liquidez e se elas possuem influência no retorno das ações brasileiras, além de entender se existe...

Mercado preditivo: um método de previsão baseado no conhecimento coletivo

OpenAIRE

Ivan Roberto Ferraz

2015-01-01

Mercado Preditivo (MP) é uma ferramenta que utiliza o mecanismo de preço de mercado para agregar informações dispersas em um grande grupo de pessoas, visando à geração de previsões sobre assuntos de interesse. Trata-se de um método de baixo custo, capaz de gerar previsões de forma contínua e que não exige amostras probabilísticas. Há diversas aplicações para esses mercados, sendo que uma das principais é o prognóstico de resultados eleitorais. Este estudo analisou evidências empíricas da efic...

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)

Castro Leiton, Karina

2014-01-01

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 [es

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.

Competencia por cantidades en los mercados de arte de México

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José Carlos Ramírez

2008-01-01

Full Text Available El artículo establece un modelo de competencia à la Cournot para determinar los precios, cantidades y poder de mercado de los principales intermediarios del mercado secundario de obras pictóricas en México. La hipótesis base es que esas tres variables dependen críticamente de la diferenciación de productos, costos y variaciones conjeturales que los intermediarios mantienen entre sí. Los resultados de las simulaciones revelan que el modelo propuesto funciona muy bien para explicar el comportamiento de los intermediarios ya que, al introducir el parámetro de diferenciación de productos, se pueden distinguir dos nichos en el mercado secundario: el de piezas únicas o altamente diferenciadas vendidas en las casas de subasta y el de obras comunes o de menor diferenciación canalizadas mediante los dealers y las galerías. Esta identificación permea todos las conclusiones de la investigación.

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

Science.gov (United States)

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

2013-05-01

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

Grado de discapacidad en pacientes hemipléjicos del "Policlínico Docente Universitario del Cerro" Evaluation of disability in hemiplegic patients from Cerro university teaching polyclinic

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Abel Estévez Perera

2012-12-01

Full Text Available Introducción: la hemiplejía como consecuencia de un ictus constituye una importante causa de discapacidad. La continuidad y calidad en el proceso rehabilitador supone mejores perspectivas en el pronóstico de los pacientes. Objetivo: evaluar el grado de discapacidad en los pacientes hemipléjicos del área de salud del Policlínico Docente Universitario del Cerro. Métodos: estudio descriptivo, transversal en los pacientes que acudieron consecutivamente al área de rehabilitación del citado policlínico, desde septiembre de 2009 hasta julio de 2011. La muestra estuvo constituida por 124 hemipléjicos por enfermedad cerebrovascular mayores de 15 años, los cuales fueron evaluados con la Escala de Discapacidad de Rosetón. Se excluyeron los enfermos con afasia sensorial o mixta y aquellos que se negaron a participar. Resultados: en 84 (67,8 % pacientes se encontró independencia para la orientación y predominó la semidependencia para el desplazamiento y las necesidades físicas. Para la higiene personal, 48 (38,7 % pacientes resultaron ser dependientes. La falta de motivación para ocupar el tiempo libre se encontró en 92 (74,2 % pacientes, casi siempre por dificultades en la convivencia y en las relaciones familiares. Conclusiones: el grado de discapacidad de los pacientes hemipléjicos evaluados viene dado por la semidependencia en el desplazamiento y las necesidades físicas y la dependencia para el autocuidado. Las dificultades en la convivencia y las relaciones familiares interfieren en la motivación del paciente para ocupar el tiempo libre.Introduction: hemiplegia is an important cause of disability as a result of a stroke. The persistence and quality of the rehabilitative process lead to better results in the patient prognosis. Objective: to evaluate the extent of disability in hemiplegic patients from the health area under "Cerro" university teaching polyclinics. Methods: a cross-sectional and descriptive study was conducted in

Un Análisis de las Variaciones de Precios Diarias en el Mercado de Liniers

OpenAIRE

Rossini, Gustavo

2007-01-01

A pesar de la importancia como mercado de referencia para la ganadería vacuna argentina, pocos estudios han examinado el comportamiento de las variaciones de los precios diarios en las categorías comercializadas en el Mercado de Liniers. Dado esto, el objetivo de este trabajo es aportar información sobre la incidencia de variables seleccionadas sobre los cambios en los precios diarios en este mercado en las categorías de mayor ingreso diario. Para ello, un Modelo Logístico Multinomial es usad...

O ENSINO SUPERIOR EM TURISMO: HUMANO OU MERCADO?

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Waléria Thabata Roldão Niquini

2013-06-01

Full Text Available Desde La creación de la educación superior en el Turismo en Brasil, en La década de 1970, se han producido algunas discusiones en relación a la formación del estudiante y su desempeño en el mercado laboral. Sin embargo hay varios puntos educativos significantes incluso antes de la aparición de la inserción profesional. La preparación de los estudiantes, las acciones de los maestros en la esfera de investigación y extensión y la necesidad del pensamiento crítico son supuestos que poden justificar tal curso mientras que la práctica educativa libertadora. Estas son las cuestiones discutidas en esta investigación destinada a comprender las perspectivas docente y dicente, en la licenciatura en Turismo, sobre la relación entre la enseñanza y el aprendizaje y sus aspectos esenciales, en una más amplia visión y menos fragmentada, entre la destacada dicotomía y el mercado de laboro y el pensamiento crítico científico. Se concluye que el debate académico sobre la educación en el Turismo todavía se disocia sólo entre los intereses del mercado y las discusiones humanas, sin una integración profunda en la relación enseñanza-aprendizaje.

Orientação para o Mercado no Segmento Hoteleiro: o caso português

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Mario Barata Raposo

2010-07-01

Full Text Available Resumo O objectivo deste estudo foi medir o grau de orientação para o mercado dos maiores grupos hoteleiros de Portugal. Após uma breve explanação sobre a orientação para o mercado e o segmento hoteleiro em Portugal apresentou-se um estudo empírico realizado junto dos maiores 20 grupos de hotéis de Portugal, utilizando como instrumento de colecta de dados, a tradicional escala Markor (Market orientation adaptada ao sector hoteleiro. Constatou-se nas organizações investigadas uma boa capacidade de geração de informações de mercado e resposta ao mercado. Porém os resultados obtidos com o constructo da disseminação de informações de mercado ficaram abaixo das expetactivas. Portanto, o desafio actual para as principais redes de hotéis de Portugal é propiciar a melhoria da disseminação interna das informações que os profissionais de marketing recolhem junto ao mercado. Palavras-chave: gestão do marketing; orientação para o mercado; markor; sector hoteleiro em Portugal. Abstract The objective of this study was to measure level of orientation for the market of the largest hotel groups of Portugal. After a brief explanation on the market orientation and the hotel segment in Portugal an empiric study was presented performed with the largest groups of 20 hotels of Portugal, using as an instrument of collection data, the traditional Markor scale (market orientation adapted to the hotel sector. It was found in the investigated organizations a good capacity to generate market information and response to the market. However the results obtained with the construct of the dissemination of market information were below the expectations. So the current challenge for the main networks of hotels in Portugal is to improve the internal dissemination of information that marketing professionals gathered at the market. Keywords: marketing management, orientation to the market, markor, hotel sector in Portugal.

Cerro Amarillo rhyolites, advanced AFC in the northern SVZ, Chile

International Nuclear Information System (INIS)

Godoy, E; Hildreth, W

2001-01-01

Cerro Amarillo is a Quaternary medium size (500m high, 2 km 2 ) rhyolite dome complex located close to the Chile-Argentina border, reaching a height of 4162 m, between the headwaters of the Rio Colina and the Nieves Negras Pass. It overlies a broad anticline of thick Middle Jurassic pelites (Alvarez et al., 1997). Thiele (1980) includes this complex in his 'Unidad Volcanica Antigua', a Pleistocene composite map unit made up of andesites and trachyandesites. Ramos et al. (1997), while recognizing its rhyolitic character, assigned a Tertiary age to the lava domes, most likely based on the late Pliocene age of silicic dikes outcropping eastward, in Argentina. Both the lack of younger overlying units and freshness of its components, together with preservation of the unconsolidated, easily eroded pyroclastic deposits at its base, suggest, however, that it is not older than Pleistocene (au)

Flores de corte y follaje en florerías y mercados de Puebla, México

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C. Tlahuextl-Tlaxcalteca

2005-01-01

Full Text Available Puebla, México, la capital del estado, es un consumidor importante de especies de flor de corte y follaje. Se elaboró un cuestionario el cual se aplicó a través de entrevistas con los dueños de florerías o encargados de ventas en seis mercados y 40 florerías. Las florerías de Puebla ofrecen más especies de flores de corte que los mercados. Los precios de flores en los mercados son más bajos, pero la calidad también es menor que en las florerías. Los mercados ofrecen varias especies de flores de corte provenientes de la producción a la intemperie (Celosia cristata, Centaurea cyanus, Gladiolus sp., Matthiola incana, Tagetes erecta. Lo interesante es que tanto las florerías como los mercados tienen amplio surtido de follaje cortado de buena calidad. El objetivo de esta investigación fue obtener información sobre la oferta y demanda de especies de flor de corte y follaje en Puebla. Asimismo, las preferencias de los hombres y las mujeres hacia estos productos

Definición del mercado de trigo cristalino en el valle del Yaqui, México

OpenAIRE

Garza Lagler, María Cristina; Taddei Bringas, Cristina

2016-01-01

Resumen: El valle del Yaqui es una región productora de trigo en el noroeste de México, cuyas agroempresas tienen una participación creciente en el mercado internacional. El objetivo de este trabajo es una aproximación a la definición del mercado del trigo cristalino que se produce en su territorio, para lo cual se realizó un análisis descriptivo apoyado en entrevistas a actores estratégicos del sistema de producción. Los resultados indican que este grano tiene tres mercados: la industria de ...

Sm-Nd whole-rock isotope system of the Eye-Dashwa Lakes pluton

International Nuclear Information System (INIS)

Futa, K.

1990-01-01

An unaltered drill-core sample of the Eye-Dashwa Lakes pluton (sample ATK-1 (990.97-996.78)) is light rare earth enriched, with a 147 Sm/ 144 Nd ratio of 0.08699 and a 143 Nd/ 144 Nd ratio of 0.510815. The depleted mantle model age of 2.68 Ga agrees with emplacement ages, indicating that parental magma or its protolith was derived directly from a depleted mantle and that the crustal residence time was short

Trace Element Geochemistry of Silica Phases: Understanding the Evolution of the Cerro Pabellón Geothermal System

Science.gov (United States)

Alvear, B.; Morata, D.; Leisen, M.; Reich, M.; Barra, F.

2017-12-01

The study of mineral textures coupled with trace element geochemistry has proven to be a useful tool to understand the evolution of geological environments. The purpose of this study is to provide new constrains on the formation of an active geothermal system, specifically the Cerro Pabellón field. The Cerro Pabellón system is located at 4500 m above sea level and is the first geothermal power plant in operation in Chile and South America. Thirteen samples were collected from a 550 m long drill core. Samples were first studied under petrographic microscopy followed by scanning electron microscopy coupled with a cathodoluminescence detector (CL-SEM). The different textures recognized using petrography and the CL-SEM technique were later analyzed by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in order to determine variations in the trace element concentrations as a function of silica textures. Two vein types (A and B) with different silica polymorphs were identified by CL-SEM. Vein type A has only a colloform texture, whereas vein type B, younger and crosscutting the type A, shows zonation, colloform, and jigsaw textures. LA-ICPMS results show high concentrations of Li, Al, Na, K, As, and Sb for all types of silica. A comparison between vein type A and B, show that vein type A is Al-Na-K-Li poor (2088, 36, 309, and 122 ppm average, respectively) and As-Sb rich (43 and 249 ppm average, respectively). On the other hand, vein type B has variable concentrations of Al-Na-K-Li-Sb, but usually higher than in vein type A. Overall, the Cerro Pabellón geothermal system shows high concentrations of Li and Sb, reaching up to 360 and 703 ppm, respectively. Our preliminary results show that the trace element geochemistry is strongly related to the different silica textures, which formed as a response to different thermodynamic conditions and fluid-rock ratios. This work is a contribution to the FONDAP-CONICYT 15090013 Project.

Efeito da orientação para o mercado sobre a lucratividade da empresa

OpenAIRE

Narver,John C.; Slater,Stanley F.

2006-01-01

Acadêmicos e profissionais de marketing vêm observando, há mais de três décadas, que o desempenho empresarial é afetado pela orientação para o mercado, mas até hoje não há uma medida válida da orientação para o mercado nem análise sistemática de seu efeito sobre o desempenho das empresas. Os autores relatam o desenvolvimento de uma medida válida de orientação para o mercado e analisam seu efeito sobre a lucratividade de uma empresa. Usando uma amostra de 140 unidades de negócio composta de em...

O MARKETING ORIENTADO PELO MERCADO [doi: 10.5329/RECADM.20050402010

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Sandro Deretti

2005-11-01

Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4 Resumo A economia globalizada determinou alterações profundas no processo estratégico das empresas, propiciando oportunidades e ameaças em todos os segmentos e exigindo produtos e serviços competitivos. Assim, diante deste cenário extremamente desafiador, a função marketing dentro das empresas assume maior importância no desenvolvimento de vantagens competitivas sustentáveis e na redução das incertezas. Muitos autores consideram que a orientação para o mercado seja a essência da filosofia empresarial que leva ao sucesso nesta luta pelos mercados porque investiga desejos e necessidades do consumidor. Este artigo faz uma contextualização dos principais trabalhos que colaboraram para a estruturação do conceito de marketing e da orientação para o mercado.   Palavras-chave: conceito de marketing; estratégia de marketing; orientação para o mercado.   Abstract The global economy determined deep changes in the companies’ strategic process, providing opportunities and threats in all segments and demanding competitive products and services. Therefore, the marketing function in the organizations takes greater importance in the development of sustainable competitive advantages. Many authors consider the market orientation as the essence of the business philosophy that leads to the success in the fight for markets because it investigates the consumer’s desires and necessities. This article analyzes the main works that contribute for construction of marketing concept and market orientation.   Key Words: marketing concept; marketing strategy; market orientation.

Petrographical and geochemical characterization and deformation conditions of the San Cristobal pluton, Sierra de Velasco, La Rioja, Argentina; Caracterizacion petrografica y geoquimica y condiciones de deformacion del pluton San Cristobal, Sierra de Velasco, La Rioja, Argentina

Energy Technology Data Exchange (ETDEWEB)

Bellos, L.I.; Toselli, A.J.; Rossi, J.N.; Grosse, P.; Rosa, J.D. de la; Castro, A.

2010-07-01

The San Cristobal pluton is a 35 km2 granitic body that outcrops at the southestern tip of the Sierra de Velasco, located west of La Rioja city, Argentina. It is formed by monzogranites and syenogranites, together with scarce granodiorites, with medium to fine-grained, equigranular to slightly porphyritic textures. Their mineral assemblage consists of quartz + microcline + plagioclase + biotite {+-} muscovite + zircon + apatite + magnetite. The granite contains dioritic to tonalitic mafic enclaves. The central and eastern parts of the granite have been deformed by the NNW-SSE trending South Mylonitic shear zone formed by mylonitic rocks. The metamorphic host-rock is represented by scarce greenschist facies xenoliths and hornfels with the high T/P assemblage K-feldspar - cordierite - biotite {+-} sillimanite. The granites are calc-alkaline, weak- to moderately peraluminous, and formed as part of a continental magmatic arc developed along the active margin of western Gondwana during the Early Paleozoic. The depth of emplacement of the San Cristobal pluton is estimated at {approx}12 km. (Author).

Time-scales of assembly and thermal history of a composite felsic pluton: constraints from the Emerald Lake area, northern Canadian Cordillera, Yukon

Science.gov (United States)

Coulson, Ian M.; Villeneuve, Mike E.; Dipple, Gregory M.; Duncan, Robert A.; Russell, James K.; Mortensen, James K.

2002-05-01

Knowledge of the time-scales of emplacement and thermal history during assembly of composite felsic plutons in the shallow crust are critical to deciphering the processes of crustal growth and magma chamber development. Detailed petrological and chemical study of the mid-Cretaceous, composite Emerald Lake pluton, from the northern Canadian Cordillera, Yukon Territory, coupled with U-Pb and 40Ar/ 39Ar geochronology, indicates that this pluton was intruded as a series of magmatic pulses. Intrusion of these pulses produced a strong petrological zonation from augite syenite, hornblende quartz syenite and monzonite, to biotite granite. Our data further indicate that multiple phases were emplaced and cooled to below the mineral closure temperatures over a time-scale on the order of the resolution of the 40Ar/ 39Ar technique (˜1 Myr), and that emplacement occurred at 94.3 Ma. Simple thermal modelling and heat conduction calculations were used to further constrain the temporal relationships within the intrusion. These calculations are consistent with the geochronology and show that emplacement and cooling were complete in less than 100 kyr and probably 70±5 kyr. These results demonstrate that production, transport and emplacement of the different phases of the Emerald Lake pluton occurred essentially simultaneously, and that these processes must also have been closely related in time and space. By analogy, these results provide insights into the assembly and petrogenesis of other complex intrusions and ultimately lead to an understanding of the processes involved in crustal development.

The ultimate fate of a synmagmatic shear zone. Interplay between rupturing and ductile flow in a cooling granite pluton

Science.gov (United States)

Zibra, I.; White, J. C.; Menegon, L.; Dering, G.; Gessner, K.

2018-05-01

The Neoarchean Cundimurra Pluton (Yilgarn Craton, Western Australia) was emplaced incrementally along the transpressional Cundimurra Shear Zone. During syndeformational cooling, discrete networks of cataclasites and ultramylonites developed in the narrowest segment of the shear zone, showing the same kinematics as the earlier synmagmatic structures. Lithological boundaries between aplite/pegmatite veins and host granitic gneiss show more intense pre-cataclasite fabrics than homogeneous material, and these boundaries later became the preferred sites of shear rupture and cataclasite nucleation. Transient ductile instabilities established along lithological boundaries culminated in shear rupture at relatively high temperature (∼500-600 °C). Here, tensile fractures at high angles from the fault plane formed asymmetrically on one side of the fault, indicating development during seismic rupture, establishing the oldest documented earthquake on Earth. Tourmaline veins were emplaced during brittle shearing, but fluid pressure probably played a minor role in brittle failure, as cataclasites are in places tourmaline-free. Subsequent ductile deformation localized in the rheologically weak tourmaline-rich aggregates, forming ultramylonites that deformed by grain-size sensitive creep. The shape and width of the pluton/shear zone and the regime of strain partitioning, induced by melt-present deformation and established during pluton emplacement, played a key role in controlling the local distribution of brittle and then ductile subsolidus structures.

Contrasting magmatic structures between small plutons and batholiths emplaced at shallow crustal level (Sierras de Córdoba, Argentina)

Science.gov (United States)

Pinotti, Lucio P.; D'Eramo, Fernando J.; Weinberg, Roberto F.; Demartis, Manuel; Tubía, José María; Coniglio, Jorge E.; Radice, Stefania; Maffini, M. Natalia; Aragón, Eugenio

2016-11-01

Processes like injection, magma flow and differentiation and influence of the regional strain field are here described and contrasted to shed light on their role in the formation of small plutons and large batholiths their magmatic structures. The final geometric and compositional arrangement of magma bodies are a complex record of their construction and internal flow history. Magma injection, flow and differentiation, as well as regional stresses, all control the internal nature of magma bodies. Large magma bodies emplaced at shallow crustal levels result from the intrusion of multiple magma batches that interact in a variety of ways, depending on internal and external dynamics, and where the early magmatic, growth-related structures are commonly overprinted by subsequent history. In contrast, small plutons emplaced in the brittle-ductile transition more likely preserve growth-related structures, having a relatively simple cooling history and limited internal magma flow. Outcrop-scale magmatic structures in both cases record a rich set of complementary information that can help elucidate their evolution. Large and small granitic bodies of the Sierra Pampeanas preserve excellent exposures of magmatic structures that formed as magmas stepped through different rheological states during pluton growth and solidification. These structures reveal not only the flow pattern inside magma chambers, but also the rheological evolution of magmas in response to temperature evolution.

MICROMUNDO PARA SIMULAR UN MERCADO ELÉCTRICO DE CORTO PLAZO

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Carlos Jaime Franco

2012-12-01

Full Text Available En este trabajo se presenta un micromundo para la simulación de una bolsa de energía, el cual se elaboró en respuesta a la necesidad de facilitar el aprendizaje del esquema de bolsa de energía con despacho centralizado a los interesados en este mercado. El micromundo cuenta con un modelo climático para simular los fenómenos de El Niño y La Niña, y con un modelo para la generación de los precios de oferta de los generadores, además es altamente parametrizable y permite simular diversos tipos de mercados eléctricos.

Magmatic-hydrothermal fluids and volatile metals in the Spirit Lake pluton and Margaret Cu-Mo porphyry system, SW Washington, USA

Science.gov (United States)

Iveson, Alexander A.; Webster, James D.; Rowe, Michael C.; Neill, Owen K.

2016-03-01

The halogen-bearing minerals tourmaline, amphibole, and biotite formed during magmatic-hydrothermal processes associated with the late-stage cooling of the Spirit Lake granitoid pluton (Mt. St. Helens, WA) and with the younger sulphide-mineralised rocks of the Margaret Cu-Mo porphyry deposit located entirely within the pluton. Major- and trace-element discrimination suggests that one tourmaline population crystallised from fractionated late-stage melt pockets in granodiorite-monzogranitic dykes of the pluton. These coarse, euhedral, oscillatory, and complexly sector-zoned uvite tourmalines span a limited range in Mg/(Mg + Fe) [Mg#] space (0.4-0.7 apfu) and show the highest Ti, Ca, F, Nb, and Ta contents, and low X-site vacancies (X-site vacancies (>0.6 apfu), lower Ca and F contents, and the highest Li, As, and HREE contents (>80 ppm Li, >1200 ppm As). This population appears to record direct, rapid crystallisation from magmatic ± meteoric fluid(s) bearing the signature of the breakdown of primary feldspars and pyroxenes, with fluid exsolution from fractionated melt patches likely triggered by the formation of the previous generation of tourmaline. Mineralised porphyry deposit tourmaline compositions from the stockwork span a much larger range in Mg# space (0.05-0.9 apfu) and are almost entirely Ca-free. X-sites of these schorl tourmalines are dominated by Na or vacancies, and the Y-sites are strongly Fe enriched. The highest Mn and Zn concentrations (>4000 and >1000 ppm, respectively) potentially reflect the composition of mineralising fluids during ore deposition. A number of boron isotopic analyses yield predominantly heavy boron, but δ11B values range from -5.2 to 6.2 ‰ and average 1.4 ‰. Whilst most plutonic tourmalines conform to reported a- and c-sector element partitioning models, those from the mineralised porphyry show large and variable sector fractionation differences, suggesting that external controls may also be important. Wider evidence for

Evidencia empírica de poder de mercado en industrias minoristas de gas natural vehicular.

OpenAIRE

García, John J.; Montenegro, Carlos Mauricio; Velásquez, Ermilson

2012-01-01

La alta concentración del mercado minorista de Gas Natural Vehicular -GNV en Colombia permite el ejercicio de poder de mercado. El mecanismo de fijación de precio de venta en las Estaciones de Servicio –EDS’s se asemeja al de un modelo teórico oligopólico de Franja Cuasi-Competitiva, en el cual se identifica una empresa líder en el mercado y otras seguidoras, tomadoras de precio. Mediante el índice Herfindahl-Hirschman (HHI) se encontró alto nivel de concentración en la industria y por medio ...

Diameter characterization of timber species in primary forests of Cerro Murrucucu

International Nuclear Information System (INIS)

Villa G, Ana Maria

2006-01-01

This study in Cerro Murrucucu forests establishes the minimum fell diameter (DMC) and its fell cycle (C). It classifies the forest in 1 (Iess damaged) and 2 (severely damaged). Ten species were selected by means of the importance Value Index (IVI) and the DMC was determined. C was estimated through the times of step method. Pentaclethra macroloba showed the highest IVI (21.5% and 21.09% for forests 1 and 2, respectively). In spite of the deterioration of forest 2 the species still showed highest importance. In forest 1 an equilibrium can be deduced, whereas in forest 2 most of the considered species show instability. The DMC for forests 1 and 2 were 30 and 20 cm respectively, indicating extractive activities are deteriorating the latest. C was 51.8 years

Loparite-(Ce) from the Khibiny Alkaline Pluton, Kola Peninsula, Russia

Science.gov (United States)

Konopleva, N. G.; Ivanyuk, G. Yu.; Pakhomovsky, Ya. A.; Yakovenchuk, V. N.; Mikhailova, Yu. A.

2017-12-01

Data on the occurrence, morphology, anatomy, composition, and formation conditions of loparite-(Ce) in the Khibiny alkaline pluton are given. Loparite-(Ce), (Na,Ce,Sr)(Ce,Th)(Ti,Nb)2O6, resulted from metasomatic alteration and assimilation of metamorphic host rocks at the contact with foyaite as well as foyaite on the contact with foidolite. This alteration was the highest in pegmatite, and albitite developed there. A decrease in temperature resulted in enrichment of the perovskite and tausonite endmembers in loparite-(Ce) owing to a decrease in the loparite and lueshite endmembers. La and Ce sharply predominate among rare earth elements in the composition of loparite-(Ce).

Geohydrologic conditions of the shallow aquifer in the Cerro Prieto geothermal field zone; Condiciones geohidrologicas del acuifero somero en la zona del campo geotermico de Cerro Prieto

Energy Technology Data Exchange (ETDEWEB)

Vazquez Gonzalez, Rogelio [CICESE, Ensenada, Baja California (Mexico)

1999-04-01

Based on geohydrologic information reported by Comision Nacional del Agua, Comision Federal de Electricidad and several academic institutions, we have performed an analysis to establish in general terms, the past and present behavior of the shallow aquifer in the Cerro Prieto geothermal zone (CPGZ). The main features of the aquifer, derived from the interpretation of the results obtained with several disciplines, are as follows: The shallow aquifer in CPGZ is part of the regional hydrologic system of the Mexicali valley basin. The basin is filled with unconsolidated delta deposits interbedded with alluvial sediments from the Sierra Cucapa, which forms an impervious boundary. Because the lack of information about the hydraulic properties of the sediments, just possible ranges of values were obtained for the hydraulic conductivity and storativity corresponding to three deposit environments: a) delta flood plain facies, b) estuarine or lagoon environment facies, c) distal alluvial fan facies. [Spanish] Con base en la informacion geohidrologica de la Comision Nacional del Agua, la Comision Federal de Electricidad e instituciones academicas, se realizo un analisis para establecer las condiciones geohidrologicas y el panorama general del comportamiento historico y actual del acuifero somero en la zona del campo geotermico de Cerro Prieto (CGCP). De la interpretacion e integracion de los resultados obtenidos de las diferentes disciplinas utilizadas en el desarrollo del estudio, se derivan las siguientes conclusiones: El acuifero somero en la zona del CGCP forma parte del acuifero regional del valle de Mexicali. La secuencia litologica en el area de estudio esta constituida por sedimentos no consolidados de origen deltaico interdigitados con sedimentos aluviales provenientes de la Sierra Cucapa, que sirve como frontera impermeable. La informacion sobre las propiedades hidraulicas de los materiales en el area de interes es limitada, por lo cual solo se determinan los

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

OpenAIRE

Federico Fuentes; Victor A. Ramos

2008-01-01

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

Zircon and allanite U-Pb ID-TIMS ages of vaugnerites from the Calzadilla pluton, Salamanca (Spain): dating mantle-derived magmatism and post-magmatic subsolidus overprint

International Nuclear Information System (INIS)

López-Moro, F.J.; Romer, R. L.; López-Plaza, M.; González Sánchez, M.

2017-01-01

Basic to intermediate high-K, high-Mg mantle-derived rocks occur throughout the Iberian Massif and are particularly important in the Tormes Dome, where vaugnerites form several stocks and small plutons. One of the largest and geochemically most variable among these plutons is the Calzadilla pluton in the Tormes Dome that crystallized at 318 ± 1.4Ma (Bashkirian; U-Pb TIMS zircon). This age reveals that the vaugnerite pluton was emplaced during the transition from late D2 extensional deformation to early D3 contractional deformation (319 to 317Ma). Large-scale extension in the area resulted, on one hand, in extensive anatexis in the crust due to quasiisothermal decompression and mica-dehydration melting and, on the other hand, in the upwelling of the mantle, which induced partial melting of the enriched domains in the lithospheric mantle. The driving reason why crustal and mantle melts were coeval is extension. The U-Pb ID-TIMS age of allanite is not related to the emplacement nor cooling of the Calzadilla vaugnerite, but it seems to be related to a younger subsolidus overprint ca. 275Ma that, in the scale of the Central Iberian Zone, corresponds to a period of hydrothermal alteration, including episyenite formation and tungsten mineralization.

Zircon and allanite U-Pb ID-TIMS ages of vaugnerites from the Calzadilla pluton, Salamanca (Spain): dating mantle-derived magmatism and post-magmatic subsolidus overprint

Energy Technology Data Exchange (ETDEWEB)

López-Moro, F.J.; Romer, R. L.; López-Plaza, M.; González Sánchez, M.

2017-07-01

Basic to intermediate high-K, high-Mg mantle-derived rocks occur throughout the Iberian Massif and are particularly important in the Tormes Dome, where vaugnerites form several stocks and small plutons. One of the largest and geochemically most variable among these plutons is the Calzadilla pluton in the Tormes Dome that crystallized at 318 ± 1.4Ma (Bashkirian; U-Pb TIMS zircon). This age reveals that the vaugnerite pluton was emplaced during the transition from late D2 extensional deformation to early D3 contractional deformation (319 to 317Ma). Large-scale extension in the area resulted, on one hand, in extensive anatexis in the crust due to quasiisothermal decompression and mica-dehydration melting and, on the other hand, in the upwelling of the mantle, which induced partial melting of the enriched domains in the lithospheric mantle. The driving reason why crustal and mantle melts were coeval is extension. The U-Pb ID-TIMS age of allanite is not related to the emplacement nor cooling of the Calzadilla vaugnerite, but it seems to be related to a younger subsolidus overprint ca. 275Ma that, in the scale of the Central Iberian Zone, corresponds to a period of hydrothermal alteration, including episyenite formation and tungsten mineralization.

Mercado de Video en Brasil

Directory of Open Access Journals (Sweden)

Luis Santero

2015-01-01

Full Text Available La autora relata la historia de las Relaciones Públicas y dice que surgieron y se desarrollaron para legitimar ante el público los intereses económicos y políticos de quienes detentan el poder. Se cuestiona sobre el por qué no aplicar las relaciones públicas, en organizaciones populares, para que mejoren su publicación y orienten sus propósitos de desarrollo. El tema que aborda las Políticas culturales en América Latina acopia un extracto de lo más trascendente de los ensayos del libro editado por Néstor García Canclini. Sobre la telenovela se afirma que esta ha llegado a ser uno de los instrumentos más importantes de la comunicación popular: por ella desfilan las identidades de las más variadas culturas brasileñas. Y en cuanto a la caricatura se relata lo que ocurrió en el Seminario taller " Caricatura y Periodismo", realizado el(9-11 de Nov.- 1987 en el CIESPAL. El estudio sobre el mercado del vídeo se ve dificultado por la imprecisión de los datos obtenidos. Los datos oficiales no siempre se aproximan a la realidad, pues el mercado de vídeo se instauró en América Latina partiendo de una lógica totalmente diversa de los equipos de sonido e imagen.

Poder del mercado, eficiencia y racionalidad

Directory of Open Access Journals (Sweden)

Francisco A. González R.

1988-04-01

Full Text Available RESUMEN El autor plantea en el presente  artículo algunas reflexiones sobre la relación entre el progreso económico y el bienestar social, señalando la conveniencia de que el estado mediante su intervención garantice una igualdad de oportunidades de la población en relación con la distribución del ingreso de forma que pueda acceder a la satisfacción adecuada de sus necesidades. Según el artículo, el libre juego de las fuerzas del mercado no conduce a una distribución satisfactoria y si bien dicho mercado puede ser eficiente, es posible que no se caracterice por su equidad o justicia distributiva. Una alternativa planteada es la descentralización de las decisiones de los planificadores del estado hacia productores individuales y una mayor aproximación de la producción a la demanda,  con una intervención del estado en la creación de incentivos a la rentabilidad de las empresas. En últimas se plantea la combinación de mecanismos propios de economías socialistas con la economía capitalista que nos caracteriza.

Geochemistry of the Serra das Melancias Pluton in the Serra da Aldeia Suite: a classic post-collisional high Ba-Sr granite in The Riacho do Pontal Fold Belt, NE Brazil

Directory of Open Access Journals (Sweden)

Marcela Paschoal Perpétuo

Full Text Available ABSTRACT: The Serra da Aldeia Suite is composed by circular or oval-shaped plutons, intrusive in meta-sedimentary and meta-volcanosedimentary rocks in the Riacho do Pontal Fold Belt, NE Brazil. The Serra das Melancias Pluton, belonging to Serra da Aldeia Suite, is located southeastern of Piaui state, near Paulistana city. These plutons represent a major magmatic expression in this area and contain important information about the late magmatic/collisional geologic evolution of the Brasiliano Orogeny. Based on petrographic and geochemical data, three facies were defined in the Serra das Melancias Pluton: granites, syenites and quartz monzonites. The rocks display high-K and alkaline to shoshonitic affinities, are metaluminous and show ferrous character. They are enriched in Light Rare Earth Elements and Large Ion Lithophile Elements, with negative anomalies in Nb, Ta and Ti. Their high Ba, Sr, K/Rb, low Rb, relatively low U, Th, Nb to very low Heavy Rare Earth Elements and Y resemble those of typical high Ba-Sr granitoids. The geochemical data suggest the emplacement of Serra das Melancias Pluton in a transitional, late to post-orogenic setting in the Riacho do Pontal Fold Belt during the late Brasiliano-Pan African Orogeny.

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

NARCIS (Netherlands)

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

2008-01-01

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

Funcionamiento del Mercado Común

OpenAIRE

Martínez Puñal, Antonio

1985-01-01

Unión aduanera: Arancel Aduanero Común. Legislación general. Simplificación de las formalidades aduaneras. Valor en aduana. Origen de las mercancías. Regímenes aduaneros económicos. Política arancelaria. Mercado interior y asuntos industriales: Libre circulación de mercancías. Libre circulación de personas y libre prestación de servicios. Derecho económico comercial. Problemas industriales. Entorno jurídico de las empresas. Pequeñas y medianas empresas. Competencia: General. Alianzas, concent...

El contrato entre “XM compañía de expertos en mercados S.A. E.S.P.” y los agentes del mercado de energía mayorista

OpenAIRE

Botero Restrepo, Clara Patricia

2006-01-01

Hace ya varios años que se han venido presentando controversias en torno al contrato que celebra “XM Compañía de Expertos en Mercados S.A. E.S.P.” –antes ISA- con los agentes del mercado de energía mayorista. Por ello se considera necesario estudiar su naturaleza jurídica, su alcance, y la jurisdicción competente para conocer de los litigios que surjan con ocasión de él.

Cristalan 836: lanzamiento de un producto innovador en un mercado comoditizado

OpenAIRE

Galarza Uchuya, Patricia Fabiola; Gallardo Ramírez, Javier Luis

2016-01-01

La tesis trata el caso de la decisión de la empresa Orica Chemicals de introducir en el mercado peruano la resina de poliéster Cristalan 836, un producto innovador que le da características de desempeño superiores a los productos existentes en el mercado, a un costo competitivo y ya lista para usar. Modasa, la empresa carrocera más grande de Perú, se interesa por el producto y hace un pedido. Una vez recibido el producto, la empresa presenta problemas porque los usuarios no están conformes y ...

Diseño de un modelo de crecimiento de mercado para una comercializadora de Maquinaria Industrial.

OpenAIRE

Medina Blancas, Adrián.

2015-01-01

El objeto de este estudio es determinar el por qué las empresas dedicadas a la comercialización de productos industriales de rehúso como lo son maquinaria, autos y algunos desechos industriales no cuentan con una participación sólida en el mercado de la compra venta en la zona centro del país. Partiendo del supuesto de que la poca explotación del mercado y sus oportunidades de crecimiento comercial son por la falta de conocimiento de oportunidad de mercado que se puede presenta...

Análisis de la transformación de los mercados de abastos madrileños

OpenAIRE

Rodríguez Sebastián, Alejandro

2015-01-01

Durante la última década, el Ayuntamiento de Madrid ha desarrollado diferentes políticas con el objetivo de revitalizar los mercados de abastos de la ciudad. Una de ellas ha sido la inserción de cadenas de supermercados junto a las estructuras comerciales tradicionales de los mercados, actuando a modo de ‘locomotoras’ económicas. Por otro lado, es reconocible la aparición en ciertos mercados de nuevos patrones de consumo, unos asociados a estilos de vida propios de élites y otros surgidos a r...

Downwelling Far-Infrared Emission Spectra Measured By First at Cerro Toco, Chile and Table Mountain, California

Science.gov (United States)

Mast, J. C.; Mlynczak, M. G.; Cageao, R.; Kratz, D. P.; Johnson, D. G.; Mlawer, E. J.; Turner, D. D.

2014-12-01

The Far-Infrared Spectroscopy of the Troposphere (FIRST) instrument is a Fourier transform spectrometer developed to measure the important far-infrared spectrum between 100 and 650 cm-1. Presented here are measurements made by FIRST during two successful deployments in a ground-based configuration to measure downwelling longwave radiation at Earth's surface. The initial deployment was to Cerro Toco, Chile, where FIRST operated from August to October, 2009 as part of the Radiative Heating in Underexplored Bands Campaign (RHUBC-II) campaign. After recalibration, FIRST was deployed to the Table Mountain Facility from September through October, 2012. Spectra observed at each location are substantially different, due in large part to the order of magnitude difference in integrated precipitable water vapor (0.3 cm at Table Mountain, 0.03 cm at Cerro Toco). Dry days for both campaigns are chosen for analysis - 09/24/2009 and 10/19/2012. Also available during both deployments are coincident radiosonde temperature and water vapor vertical profiles which are used as inputs a line-by-line radiative transfer program. Comparisons between measured and modeled spectra are presented over the 200 to 800 cm-1 range. An extensive error analysis of both the measured and modeled spectra is presented. In general, the differences between the measured and modeled spectra are within their combined uncertainties.

Insights into the emplacement of upper-crustal plutons and their relationship to large silicic calderas, from field relationships, geochronology, and zircon trace element geochemistry in the Stillwater - Clan Alpine caldera complex, western Nevada, USA

Science.gov (United States)

Colgan, Joseph P.; John, David A.; Henry, Christopher D.; Watts, Kathryn E.

2018-01-01

Geologic mapping, new U-Pb zircon ages, and new and published 40Ar/39Ar sanidine ages document the timing and extent of Oligocene magmatism in the southern Stillwater Range and Clan Alpine Mountains of western Nevada, where Miocene extension has exposed at least six nested silicic calderas and underlying granitic plutons to crustal depths locally ≥ 9 km. Both caldera-forming rhyolitic tuffs and underlying plutons were emplaced in two episodes, one from about 30.4-28.2 Ma that included the Deep Canyon, Job Canyon, and Campbell Creek calderas and underlying plutons, and one from about 25.3-24.8 Ma that included the Louderback Mountains, Poco Canyon, and Elevenmile Canyon calderas and underlying plutons. In these two 1-2 m.y. periods, almost the entire Mesozoic upper crust was replaced by Oligocene intrusive and extrusive rocks to depths ≥ 9 km over an estimated total area of 1500 km2 (pre-extension). Zircon trace element geochemistry indicates that some plutonic rock can be solidified residual magma from the tuff eruptions. Most plutons are not solidified residual magma, although they directly underlie calderas and were emplaced along the same structures shortly after to as much as one million years after caldera formation. Magma chambers and plutons grew by floor subsidence accommodated by downward transfer of country rocks. If other Great Basin calderas are similar, the dense concentration of shallowly exposed calderas in central Nevada is underlain by a complexly zoned mid-Cenozoic batholith assembled in discrete pulses that coincided with formation of large silicic calderas up to 2500-5000 km3.

Zircon U-Pb age, Lu-Hf isotope, mineral chemistry and geochemistry of Sundamalai peralkaline pluton from the Salem Block, southern India: Implications for Cryogenian adakite-like magmatism in an aborted-rift

Science.gov (United States)

Renjith, M. L.; Santosh, M.; Li, Tang; Satyanarayanan, M.; Korakoppa, M. M.; Tsunogae, T.; Subba Rao, D. V.; Kesav Krishna, A.; Nirmal Charan, S.

2016-01-01

The Sundamalai peralkaline pluton is one among the Cryogenian alkaline plutons occurring in the Dharmapuri Rift Zone (DRZ) of the Salem Block in the Southern Granulite Terrane (SGT) of India. Here we present zircon U-Pb age and Lu-Hf isotopic composition, mineral chemistry and geochemistry of the pluton to explore the petrogenesis and geodynamic implications. Systematic modal variation of orthoclase, Na-plagioclase, Ca-amphibole (ferro-edenite and hastingsite) and quartz developed quartz-monzonite and granite litho units in the Sundamalai pluton. Thermometry based on amphibole-plagioclase pair suggests that the pluton was emplaced and solidified at around 4.6 kbar pressure with crystallization of the major phases between 748 and 661 °C. Estimated saturation temperature of zircon (712-698 °C) is also well within this range. However, apatite saturation occurred at higher temperatures between 835 and 870 °C, in contrast with monazite saturation (718-613 °C) that continued up to the late stage of crystallization. Estimated oxygen fugacity values (log fO2: -14 to -17) indicate high oxidation state for the magma that stabilized titanite and magnetite. The magmatic zircons from Sundamalai pluton yielded a weighted mean 206Pb/238U age of 832.6 ± 3.2 Ma. Geochemically, the Sundamalai rocks are high-K to shoshonitic, persodic (Na2O/K2O ratio > 1), silica-saturated (SiO2:65-72 wt.%), and peralkaline in composition (aluminum saturation index, ASI Sc(2-3 ppm), positive Sr anomaly and predominantly negative zircon εHf(t) values (-10.8 to -9.3 with an average of -10.2) and initial 176Hf/177Hf ratios (0.281947-0.282022) confirm a Paleoproterozoic crustal source. Based on the field and geochemical evidences, we propose that a previously metasomatized mafic lower-crustal source enriched in alkalis has undergone CO2-present partial melting as a result of asthenospheric upwelling beneath an aborted rifting along the DRZ generating the magma that crystallized the Sundamalai rocks

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.

La estrategia competitiva que adopta la empresa transnacional en el mercado global

OpenAIRE

Adalberto Cabello Chávez; Rafael Reyes; Pedro Solís Pérez

2006-01-01

La aldea global es un mundo sin fronteras, sin límites, sin residencia, donde circulan libremente individuos, mercancías y capital. Las instituciones de la aldea global están conformadas por el estado regional, la empresa transnacional y el mercado global, de las cuales la que se acopla y domina a la aldea es la empresa transnacional, que utiliza diversas estrategias competitivas para controlar el mercado global a través de la organización multinacional con gestión centralizada...

Sistema de gestión en los mercados municipales de Castilla y León

OpenAIRE

Peña Santiago, Eder

2015-01-01

El objetivo principal es analizar la gestión de los mercados municipales de abastos de Castilla y León fundamentalmente a través de dos análisis. En primer lugar a través de un análisis estadístico de los datos aportados por los gerentes en los mercados de Castilla y León. En segundo lugar a través de un análisis estadístico de la importancia y la opinión de los comerciantes sobre el modelo de gestión en los mercados de Castilla y León. Grado en Comercio

ALCANCES, LIMITACIONES E IMPACTO DE LA REFORMA A LA LEY REGULADORA DEL MERCADO DE VALORES

Directory of Open Access Journals (Sweden)

Julio César Espinosa Rodríguez

2011-09-01

Full Text Available La nueva ley de valores establece una serie de parámetros requeridos para el desarrollo del mercado de valores, enmarcado dentro de una mejor regulación y mayor seguridad para los inversionistas. En general establece las bases para pasar a una nueva etapa de desarrollo del sistema financiero, donde el énfasis será el mercado de largo plazo. Asimismo, la propuesta de la Bolsa Nacional de Valores para desarrollar el mercado accionario se ha transformado en un mecanismo complementario a ese cometido, donde la actuación de la Superintendencia General de Valores ha buscado catalizar ese proceso.

O MODELO DE GREENBLATT: EVIDÊNCIAS NO MERCADO DE AÇÕES BRASILEIRO ENTRE 2002 E 2012

Directory of Open Access Journals (Sweden)

Ricardo dos Santos Dias

2015-08-01

Full Text Available A dinâmica e a competitividade do mercado de capitais exigem uma velocidade de resposta ótima e um nível de conhecimento por parte do investidor, que muitas vezes o impede de decidir em tempo hábil. O presente artigo tem por objetivo analisar a eficiência dos fundamentos contidos no modelo proposto por Greenblatt (2007 no mercado de ações brasileiro, avaliando se a simplicidade da análise proposta possibilita resultados sustentáveis. Como forma de comparação foi utilizado o resultado gerado pelo portfólio proposto, no período de 2002 a 2012, com índices de mercado. O resultado acumulado da carteira foi superior a 310%, quase duas vezes superior ao maior rendimento apurado dentre os índices comparativos. Um teste de diferença de médias permitiu inferir que os resultados do modelo proposto por Greenblatt (2007 podem gerar retornos estatisticamente diferentes da média do mercado. Palavras-chave: Mercado de capitais. Investimentos. Ações.

Processos globais e mercado de trabalho: novas dinâmicas no setor automotivo no Brasil - anos 2000

Directory of Open Access Journals (Sweden)

Garcia, Sandro Ruduit

2007-01-01

Full Text Available O artigo tenta identificar novas dinâmicas no mercado de trabalho, face aos processos globais, a partir do que vem ocorrendo no setor automotivo brasileiro nos anos 2000, focando particularmente o caso do pólo de Gravataí (RS. O argumento central da análise é de que a constituição de processos globais promove novas dinâmicas em mercados de trabalho regionais. A abertura de mercados de produtos, as composições entre capitais nacionais e estrangeiros e os investimentos em novas plantas industriais expressam processos globais que poderiam criar novas atividades e funções produtivas, empresas e empregos, assim como estimular capacidades e conhecimentos. Por outro lado, a competitividade, instabilidade e interdependência do sistema global reforçariam a seletividade social nos mercados de trabalho regionais, constituindo novos riscos e ansiedades para segmentos econômicos e sociais vulneráveis. Isso tenderia a mobilizar instituições no esforço de tentar reparar distorções face à nova complexidade do mercado de trabalho

Relative contributions of crust and mantle to generation of Campanian high-K calc-alkaline I-type granitoids in a subduction setting, with special reference to the Harsit Pluton, Eastern Turkey

NARCIS (Netherlands)

Karsli, O.; Dokuz, A.; Uysal, I.; Aydin, F.; Chen, B.; Kandemir, R.; Wijbrans, J.R.

2010-01-01

We present elemental and Sr-Nd-Pb isotopic data for the magmatic suite (~79 Ma) of the Harşit pluton, from the Eastern Pontides (NE Turkey), with the aim of determining its magma source and geodynamic evolution. The pluton comprises granite, granodiorite, tonalite and minor diorite (SiO

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.

La sensibilidad de los parámetros en el mercado potencial y actual de una organización

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Francisco Javier Landa Bercebal

2015-07-01

Full Text Available El sistema del mercado compuesto por el entorno, las organizaciones en competencia y los consumidores/compradores realizan una interacción permanente que se concreta en una trayectoria dinámica. Si el mercado se divide en mercado actual y mercado potencial, el cambio de los consumidores/compradores del uno al otro o simplemente la entrada al mercado actual de una organización cualquiera suponen también un proceso dinámico que depende de variables exógenas al sistema y del valor de los parámetros de ajuste, cuyo origen está en la manera de comportamiento de los individuos que componen el sistema estudiado. La sensibilidad y el estudio de esos valores de los parámetros requieren conocer la posible tendencia del sistema, así como el comportamiento del mismo, dependiendo de la región paramétrica en la que se encuentre.

La importancia de la inteligencia de mercados en la actividad exportadora de las empresas españolas

OpenAIRE

Navarro-García, Antonio; Barrera-Barrera, Ramón; Peris-Ortiz, Marta

2013-01-01

El objetivo de la presente investigación es responder al gap investigador existente en la literatura sobre el rol que juega la inteligencia de mercados en la actividad exportadora. Específicamente se pretende conocer los efectos que ejerce la inteligencia de mercados en las interrelaciones entre las distancias de mercados (doméstico vs. extranjeros) percibidas por los responsables de exportación, las decisiones estratégicas de marketing mix (estandarización vs. adaptación) y el...

Changing fluvial styles in volcaniclastic successions: A cretaceous example from the Cerro Barcino Formation, Patagonia

Science.gov (United States)

Umazano, A. Martín; Krause, J. Marcelo; Bellosi, Eduardo S.; Perez, Mariano; Visconti, Graciela; Melchor, Ricardo N.

2017-08-01

The Cretaceous Puesto La Paloma (PLPM) and Cerro Castaño (CCM) members (Cerro Barcino Formation, Chubut Group) are pyroclastic-rich, alluvial successions deposited in the Somuncurá-Cañadón Asfalto Basin during sag and endorheic conditions. The PLPM comprises sheet-like tuffaceous sandstone strata, whereas the overlying CCM includes sheet-to ribbon-channel sandstone bodies intercalated within tuffaceous and fine-grained sediments. In this context, the goals of this contribution were: i) to make a detailed documentation of the contrasting sedimentary palaeonvironments; and ii) to infer the allocyclic controls that governed the sedimentation of both units. The study area is located in the western sector of the basin, where six localities, which were studied. Six facies associations were defined including ash-falls, sheet-floods, shallow lakes, aeolian, fluvial channel-belts, and reworked debris-flows. We defined four stratigraphic intervals for the studied sections, denominated 1 to 4 in chronological order of deposition, which increase their thicknesses toward the Puesto Mesa-Cerro León site. The interval 1 (18-42 m thick) corresponds to the PLPM and includes numerous pedogenized sheet-flood deposits, carbonate-rich lacustrine, aeolian sandy facies, and ash-fall beds. The interval 1 is interpreted as an ephemeral and unconfined alluvial system that interacted with aeolian dunes and dry interdune zones. The interval 2 (20-47 m thick) represents the lower part of the CCM. It shows an alternation of fluvial channel-belt deposits and vegetated floodplain facies with sediments originated from sheet-floods, lakes, and few ash-falls and debris-flows. The mean palaeoflow was toward E-SE, except in the northernmost locality where the drainage was towards SW. Proportion of channel-belt bodies ranges from 10 to 36%, reaching higher values in the northern part of the study area, where they are also thicker. The interval 2 represents a permanent, meandering or locally low

Volatilidade e causalidade: evidências para o mercado à vista e futuro de índice de ações no Brasil

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Ana Beatriz C. Galvão

2000-01-01

Full Text Available O objetivo deste artigo é verificar a relação entre o mercado futuro e o mercado à vista no Brasil, de forma a observar o comportamento da volatilidade nesses mercados e inferir relações de causalidade. A análise utiliza o mercado de ações, em um período bastante instável, incluindo a ocorrência de choques externos e um grande aumento na entrada de capital para investimento em bolsa. A hipótese de causalidade entre os mercados futuro e à vista é testada utilizando-se os correlogramas cruzados das volatilidades e um modelo GARCH bivariado. Os resultados nos permitem afirmar que o mercado à vista lidera a transmissão de informações no mercado, o que implica que o mercado futuro não causa aumento de volatilidade no mercado à vista.The objective of this paper is to evaluate the evidence of causality between the future and spot markets of stocks in Brazil, verifying if the former has unstabilized the latter, thus increasing its volatility. We analyse a period that includes external shocks and changes in the exchange rate policy. Causality from future to spot markets is tested using both the volatilities cross-correlogram and a bivariate GARCH model. The results allow us to state that the spot market leads the information transmission of the market. Thus the future market does not cause increase of volatility in the spot market.

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

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William H.J. Strosnider

2015-01-01

Full Text Available El drenaje acido de minas (DAM es un problema a nivel mundial. El co-tratamiento pasivo de DAM con aguas residuales municipales (ARM es una manera efectiva y de bajo costo que utiliza los nutrientes de ARM para tratar las concentraciones de metales y sulfato en DAM. Cerro Rico de Potosí, Bolivia es una de las grandes ciudades mineras en el mundo que tiene muchos problemas con el DAM. El objetivo de este estudio fue determinar velocidades de reacción de Al, Fe, Mn, Zn, y otros metales en DAM provenientes de un flujo de agua en Cerro Rico usando un sistema reactor de tres etapas. El DAM tenía un pH de 3.58, acidez de 1080 mg/L equivalente a CaCO3 conteniendo concentraciones de 12, 68, 17, y 550 mg/L de Al, Fe, Mn y Zn respectivamente. Las velocidades de reacción de Al, Fe, Mn y Zn fueron de 1.43, 2.09, 0.01 y 0.10 d-1, respectivamente.

Uranium and Molybdenum extraction from a Cerro Solo deposit ore

International Nuclear Information System (INIS)

Becquart, Elena T.; Arias, Maria J.; Fuente, Juan C. de la; Misischia, Yamila A.; Santa Cruz, Daniel E.; Tomellini, Guido C.

2009-01-01

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)

PROGRESO TÉCNICO Y PODER DE MERCADO EN LA INDUSTRIA FARMACÉUTICA

OpenAIRE

GALLEGO, JOSÉ

2009-01-01

En este artículo se presenta la estimación del poder de mercado en la industria farmacéutica colombiana durante 1982 - 2004. El resultado se compara con las estimaciones realizadas para los Estados Unidos y Finlandia. La conclusión fundamental es la confirmación de la existencia de poder de mercado, al estimarse un índice de Lerner mayor que cero y un markup de Hall mayor que uno; la estimación es equivalente al 0.92 y 0.95 del poder presente en Estados Unidos y Finlandia, respectivamente. ...

Fecundidade e participação no mercado de trabalho brasileiro

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Marina Silva Cunha

2016-08-01

Full Text Available Este trabalho analisa os determinantes da fecundidade e da participação das mulheres no mercado de trabalho brasileiro. São utilizadas as informações da Pesquisa Nacional por Amostra de Domicílio do IBGE, de 1995 até 2009, e o modelo probit bivariado. Conforme o esperado, observou-se queda da fecundidade e aumento da participação no período estudado, bem como efeito negativo dos salários na probabilidade de fecundidade e positivo na probabilidade de participação no mercado de trabalho. Além disso, outras variáveis de controle incluídas relacionadas às características pessoais, condição na família e local de residência também afetam a fecundidade e a inserção das mulheres. Ademais, verificou-se que, na cauda inferior da distribuição da renda domiciliar, o efeito dos salários na fecundidade é maior, mas, no caso do engajamento no mercado de trabalho, é menor.

Redes alimentarias alternativas en grandes ciudades: los mercados de productores agrarios en Madrid

OpenAIRE

Ricardo Méndez Gutiérrez del Valle; Obdulia Monteserín Abella

2017-01-01

Las redes alimentarias alternativas constituyen una temática de investigación emergente en los estudios urbanos, que cuestiona los modelos dominantes de producción, distribución y consumo de alimentos. Una de sus manifestaciones son los mercados de productores, que ponen en contacto directo a productores periurbanos y rurales con consumidores urbanos, favoreciendo las relaciones de proximidad y los circuitos cortos. El artículo investiga los mercados de productores en Madrid mediante una estr...

Relação entre Valor de Mercado e Ativo Intangível na Bovespa

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Eduardo de Paula e Silva Chaves

2013-07-01

Full Text Available O valor de mercado das ações das empresas, negociados em bolsa, deve traduzir as expectativas dos investidores. E, muito embora os preços dessas ações estejam sujeitos à lei da oferta e da procura, diferentes métodos de avaliação, que utilizam diferentes indicadores contábeis, dados econômicos e interpretações subjetivas, podem gerar desvios no valor percebido das empresas. Este valor de mercado organizacional é conhecido como o preço da ação multiplicado pelo número das ações presentes para negociação. Esta equidade é uma questão de interesse para gestores contábeis, políticos e investigadores (Choi, 2000. É buscar a predição dos valores de mercado de empresas abertas, a partir das expectativas de valorização por parte dos acionistas. Para tanto é necessário entender a relação existente entre o retorno do ativo intangível e o retorno do valor de mercado das empresas da amostra, utilizada nos últimos cinco períodos, sendo esse o objetivo principal do trabalho. Este trabalho se enquadra numa pesquisa analítica, indutiva e básica (Collis; Hussey, 2005. Compreende uma pesquisa qualitativo-quantitativa na área de administração, finanças coorporativas e mercado financeiro brasileiro (Cherobim, 2003. Assim, responde-se à pergunta de pesquisa com algumas técnicas estatísticas, uma vez que o artigo não abrange todas as possibilidades de relações existentes entre as duas variáveis de forma estatística, mas tem forte capacidade de indicar a não predição do valor de mercado pelos ativos incorpóreos organizacionais.

Cercas e pontes: o movimento GLBT e o mercado GLS na cidade de São Paulo

OpenAIRE

Isadora Lins França

2006-01-01

A presente dissertação é um estudo sobre o movimento GLBT (Gays, Lésbicas, Bissexuais e Transgêneros) e as relações desenvolvidas por esse movimento com um mercado segmentado destinado a homossexuais, ou mercado GLS (Gays, Lésbicas e Simpatizantes). O trabalho procura compreender essas relações a partir da pesquisa de campo realizada com foco na Associação da Parada do Orgulho GLBT de São Paulo (APOGLBT). Além disso, há um esforço no sentido de entender as dinâmicas do mercado GLS e do movime...

Aplicación del régimen de abuso de mercado (operaciones con información privilegiada y la manipulación del mercado): ¿hacia un modelo integrador de la aplicación de la ley penal y administrativa en la UE?

NARCIS (Netherlands)

Vervaele, John; Luchtman, Michiel

2015-01-01

El texto estudia las normas relativas al abuso de mercado en la Unión Europea, la aplicación de la regulación de los mercados financieros y la manipulación del mercado. Así mismo, a partir del análisis de dos casos, muestra como en el marco de la regulación actual las autoridades nacionales en la UE

Intrusion of basaltic magma into a crystallizing granitic magma chamber: The Cordillera del Paine pluton in southern Chile

Science.gov (United States)

Michael, Peter J.

1991-10-01

The Cordillera del Paine pluton in the southernmost Andes of Chile represents a deeply dissected magma chamber where mafic magma intruded into crystallizing granitic magma. Throughout much of the 10x15 km pluton, there is a sharp and continuous boundary at a remarkably constant elevation of 1,100 m that separates granitic rocks (Cordillera del Paine or CP granite: 69 77% SiO2) which make up the upper levels of the pluton from mafic and comingled rocks (Paine Mafic Complex or PMC: 45 60% SiO2) which dominate the lower exposures of the pluton. Chilled, crenulate, disrupted contacts of mafic rock against granite demonstrate that partly crystallized granite was intruded by mafic magma which solidified prior to complete crystallization of the granitic magma. The boundary at 1,100 m was a large and stable density contrast between the denser, hotter mafic magma and cooler granitic magma. The granitic magma was more solidified near the margins of the chamber when mafic intrusion occurred, and the PMC is less disrupted by granites there. Near the pluton margins, the PMC grades upward irregularly from cumulate gabbros to monzodiorites. Mafic magma differentiated largely by fractional crystallization as indicated by the presence of cumulate rocks and by the low levels of compatible elements in most PMC rocks. The compositional gap between the PMC and CP granite indicates that mixing (blending) of granitic magma into the mafic magma was less important, although it is apparent from mineral assemblages in mafic rocks. Granitic magma may have incorporated small amounts of mafic liquid that had evolved to >60% SiO2 by crystallization. Mixing was inhibited by the extent of crystallization of the granite, and by the thermal contrast and the stable density contrast between the magmas. PMC gabbros display disequilibrium mineral assemblages including early formed zoned olivine (with orthopyroxene coronas), clinopyroxene, calcic plagioclase and paragasite and later-formed amphibole

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

International Nuclear Information System (INIS)

Masquelin, E.

2004-01-01

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 [es

Geochronology of plutonic rocks and their tectonic terranes in Glacier Bay National Park and Preserve, southeast Alaska: Chapter E in Studies by the U.S. Geological Survey in Alaska, 2008-2009

Science.gov (United States)

Brew, David A.; Tellier, Kathleen E.; Lanphere, Marvin A.; Nielsen, Diane C.; Smith, James G.; Sonnevil, Ronald A.

2014-01-01

We have identified six major belts and two nonbelt occurrences of plutonic rocks in Glacier Bay National Park and Preserve and characterized them on the basis of geologic mapping, igneous petrology, geochemistry, and isotopic dating. The six plutonic belts and two other occurrences are, from oldest to youngest: (1) Jurassic (201.6–145.5 Ma) diorite and gabbro of the Lituya belt; (2) Late Jurassic (161.0–145.5 Ma) leucotonalite in Johns Hopkins Inlet; (3) Early Cretaceous (145.5–99.6 Ma) granodiorite and tonalite of the Muir-Chichagof belt; (4) Paleocene tonalite in Johns Hopkins Inlet (65.5–55.8 Ma); (5) Eocene granodiorite of the Sanak-Baranof belt; (6) Eocene and Oligocene (55.8–23.0 Ma) granodiorite, quartz diorite, and granite of the Muir-Fairweather felsic-intermediate belt; (7) Eocene and Oligocene (55.8–23.0 Ma) layered gabbros of the Crillon-La Perouse mafic belt; and (8) Oligocene (33.9–23.0 Ma) quartz monzonite and quartz syenite of the Tkope belt. The rocks are further classified into 17 different combination age-compositional units; some younger belts are superimposed on older ones. Almost all these plutonic rocks are related to Cretaceous and Tertiary subduction events. The six major plutonic belts intrude the three southeast Alaska geographic subregions in Glacier Bay National Park and Preserve, from west to east: (1) the Coastal Islands, (2) the Tarr Inlet Suture Zone (which contains the Border Ranges Fault Zone), and (3) the Central Alexander Archipelago. Each subregion includes rocks assigned to one or more tectonic terranes. The various plutonic belts intrude different terranes in different subregions. In general, the Early Cretaceous plutons intrude rocks of the Alexander and Wrangellia terranes in the Central Alexander Archipelago subregion, and the Paleogene plutons intrude rocks of the Chugach, Alexander, and Wrangellia terranes in the Coastal Islands, Tarr Inlet Suture Zone, and Central Alexander Archipelago subregions.

Sm-Nd, Rb-Sr and K-Ar age constraints of the El Molle and Barroso plutons, western Sierra de San Luis, Argentina

International Nuclear Information System (INIS)

Sato, A.M.; Gonzalez, P.D; Petronilho, L.A; Llambias, E.J.; Varela, R; Basei, M.A.S

2001-01-01

Within the Early Paleozoic Famatinian orogeny of Southern Sierras Pampeanas (Sierra de San Luis and Sierra de Cordoba), the post-orogenic granitoids are characterized by circular intrusions. The published Rb-Sr and K-Ar ages from plutons in the Sierra de San Luis range between 408 and 320 Ma (see synthesis in Llambias et al., 1998). The El Molle and Barroso plutons (Sims et al., 1997; Gonzalez and Sato, 2000) are the two main exposures of a post-orogenic intrusive complex located in the western area of the Sierra de San Luis basement. They also exhibit an overall circular map view of almost 8 km in diameter, and are emplaced in a metamorphic complex developed through pre-Famatinian (Proterozoic? to Early Paleozoic) to Famatinian (Early Paleozoic) orogenies (Gonzalez and Llambias, 1998; von Gosen and Prozzi, 1998). We are carrying out isotopic datings of the El Molle and Barroso plutons in order to contribute to the understanding of the magmatic and metamorphic evolution of the final stages of the Famatinian orogenic cycle in the Sierra de San Luis. The first results of the Sm-Nd, Rb-Sr and K-Ar dates are here presented (au)

Oxygen isotope exchange kinetics between coexistent minerals and water in the Ertaibei granite pluton, northern Xinjiang

Institute of Scientific and Technical Information of China (English)

刘伟; 李志安; 赵志忠

1996-01-01

Coexistent minerals quartz, feldspar and biotite vary widely in δ18O value and display remarkable 18O/16O disequilibrium relations in the Ertaibei granite pluton, northern Xinjiang. The 18O/16O exchange reaction definitely occurred between granite and water. Initial δ18O values of the granite and exotic water are evaluated by the mass balance consideration. The results show that the 18O/16O exchange reaction is not necessarily accompanied by what geologists describe as petrological and mineralogiesl alteration effects, indicating that the exchange reaction occurs at a comparatively high temperature during subsolidus cooling of magmas. Exchange mechanism is mainly controlled by diffusion. It is demonstrated through quantitative modelling that the hydrothermal system associated with the Ertaibei pluton lived for 0.8-3 Ma, with a fluid flow rate of 3 × 10-14 mol · s-1 and water/rock (W/R) ratio of 0.79 - 3.08. Flow path and initial heterogeneity of the exotic metamorphic fluid are modelled with the δ1

Titulación de la propiedad y mercado de tierras

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Julio Calderón Cockburn

2011-05-01

Full Text Available Este estudio analiza la relación entre la tenencia de títulos de propiedad (registrados y los mercados inmobiliarios en zonas de la ciudad que tuvieron un origen informal y/o ilegal. Al hacerlo plantea cuestionamientos a los presupuestos internacionales y encuentra paradojas en el funcionamiento del mercado de suelo popular. La metodología es cuantitativa y cualitativa. Las conclusiones muestran que en asentamientos no consolidados la tenencia de un título de propiedad contribuye a un mayor valor de los predios con relación a aquellos no titulados. No obstante, el título de propiedad no necesariamente está induciendo al predominio de mercados inmobiliarios formales, sino que más bien se mantienen las tendencias que apuntan a las transacciones informales en cuanto a alquileres, compras y ventas.This study analyzes the relationship between recorded land titles and real estate markets in areas of Lima, Peru, that were settled informally and/or illegally. It uses both quantitative and qualitative methodologies. It shows that, in settlements in the process of consolidation, titled land has higher market value than land without a title. However, the existence of a recorded title does not necessarily contribute to the predominance of formal real estate market transactions; in fact, the trend of informal transactions in rentals, purchases and sales persists.

The Shahewan rapakivi-textured granite – quartz monzonite pluton, Qinling orogen, central China: mineral composition and petrogenetic significance

Directory of Open Access Journals (Sweden)

Xiaoxia Wang

2002-01-01

Full Text Available The Mesozoic Shahewan pluton consists of four texturally different types of biotite-hornblende quartz monzonite. In the porphyritic types alkali feldspar occurs as euhedral or ovoidal megacrysts that are often mantled by one or more plagioclase shells, and as smaller grains in the groundmass. Quartz, plagioclase (An20–28, biotite, and hornblende occur as inclusions in the alkali feldspar megacrystsand, more abundantly, in the groundmass. Euhedral quartz crystals in the groundmass are not as common and well developed as in typical rapakivi granite. Compared to typical rapakivi granites, the mafic minerals (biotite and hornblende are rich in Mg and poor in Fe, and the whole rock is low in Si, K, F, Ga, Zr, LREE, Fe/Mg, and K/Na. The rocks of the Shahewan pluton are thus regarded as rapakivi-textured quartz monzonites and granites but not true rapakivi granites.

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

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

Science.gov (United States)

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

2007-05-01

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

Insights into the emplacement of upper-crustal plutons and their relationship to large silicic calderas, from field relationships, geochronology, and zircon trace element geochemistry in the Stillwater – Clan Alpine caldera complex, western Nevada, USA

Science.gov (United States)

Colgan, Joseph P.; John, David A.; Henry, Christopher D.; Watts, Kathryn E.

2018-01-01

Geologic mapping, new U-Pb zircon ages, and new and published 40Ar/39Ar sanidine ages document the timing and extent of Oligocene magmatism in the southern Stillwater Range and Clan Alpine Mountains of western Nevada, where Miocene extension has exposed at least six nested silicic calderas and underlying granitic plutons to crustal depths locally ≥ 9 km. Both caldera-forming rhyolitic tuffs and underlying plutons were emplaced in two episodes, one from about 30.4–28.2 Ma that included the Deep Canyon, Job Canyon, and Campbell Creek calderas and underlying plutons, and one from about 25.3–24.8 Ma that included the Louderback Mountains, Poco Canyon, and Elevenmile Canyon calderas and underlying plutons. In these two 1–2 m.y. periods, almost the entire Mesozoic upper crust was replaced by Oligocene intrusive and extrusive rocks to depths ≥ 9 km over an estimated total area of ~ 1500 km2 (pre-extension). Zircon trace element geochemistry indicates that some plutonic rock can be solidified residual magma from the tuff eruptions. Most plutons are not solidified residual magma, although they directly underlie calderas and were emplaced along the same structures shortly after to as much as one million years after caldera formation. Magma chambers and plutons grew by floor subsidence accommodated by downward transfer of country rocks. If other Great Basin calderas are similar, the dense concentration of shallowly exposed calderas in central Nevada is underlain by a complexly zoned mid-Cenozoic batholith assembled in discrete pulses that coincided with formation of large silicic calderas up to 2500–5000 km3.

MERCADO FUTURO DE CAFÉ : UM ESTUDO DE CASO.

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TÁCITO AUGUSTO FARIAS

2014-08-01

Full Text Available Resumo: O café é a commodity agrícola brasileira que possui o mercado mais desenvolvido, dentre os contratos negociados na Bolsa de Mercadorias e Futuros (BM&F é o que apresenta negociações em maior volume, além de apresentar maiores volatilidades, tornando as operações de hedge uma importante ferramenta para diminuição de riscos para quem participa desse mercado. Realizando o hedge, o produtor acaba eliminando totalmente o risco de variação do preço só que passa a lidar o risco de variação de base. Deste modo, objetivou-se identificar o modelo mais adequado à análise do risco de base do café por meio dos índices Esalq e BM&F Os resultados empíricos sugerem a necessidade de modelagem da série pelo modelo ARIMA (Autorregressivo – Integrado – Média Móvel. Também foram utilizados os resultados da estatística U-Theil, que apresentam bons indicadores para fins de previsão.

ANÁLISIS INTRODUCTORIO AL MERCADO DUAL DE TRABAJO

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Julio Cesar Riascos

2007-07-01

Full Text Available En el artículo se examina el fenómeno de la informalidad a la luz del modelo dual del mercado de trabajo. Con ese objetivo, se ilustra al lector, cómo a partir de la dinámica suscitada en el sector formal de la economía laboral, se desprenden efectos simultáneos en la plataforma informal de trabajo. En particular, se estudia el impacto de un incremento en los salarios reales, ambos casos a través de una externalidad originada en acciones de política económica gubernamental; a juzgar por sus efectos, se conviene la existencia de un estrecho vínculo entre las dos partes a través de sus interacciones; en ese mismo sentido, se reconoce la trascendencia del mercado informal en el sostenimiento de la tesis neoclásica de pleno empleo y, se advierte como tarea indispensable la redefinición del concepto de formalidad y subempleo, dadas por supuesto sus implicaciones, esta última parte posibilita estructurar una crítica social al modelo.

ORDEN MONETARIO DE LAS ECONOMÍAS DE MERCADO

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Michel Aglietta

Full Text Available Al explicar el mercado a partir de la institución monetaria y no al revés, como es costumbre en los economistas, este artículo ofrece una nueva visión para comprender la naturaleza del dinero, las condiciones de viabilidad de la sociedad de mercado, el origen y control de las crisis financieras y monetarias y finalmente, tratar la independencia del Banco Central como una organización institucional particular que se propone para la regulación del sistema cada día más globalizado.In explaining the market takinq as a starting point the monetary institution and not the contrary, as most economists usually do, this article offers a new approach in arder to understand the nature of money, the conditions for the viability of a market society, the origin and control of financial and monetary crisis and, finally, to understand the independence of the Central Bank as a particular institutional organization that is proposed in order to regulate a system that is progressively more globalized.

El efecto fin de mes en los principales mercados accionarios latinoamericanos

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Werner Kristjanpoller Rodríguez

2015-01-01

Full Text Available En los mercados accionarios es frecuente encontrar anomalías de calendario, las cuales han sido objeto de diversos estudios en estas últimas décadas, incluso demostrándose que algunas de ellas a través del tiempo han ido desapareciendo. En este contexto, este artículo analiza una de estas anomalías, el efecto fin de mes, tanto en rendimiento como en volatilidad en los mercados accionarios de seis países latinoamericanos; a saber, Brasil, México, Chile, Colombia, Perú y Argentina en el periodo 1993-2011. La importancia de este estudio radica en poder probar si el efecto de fin de mes ha ido desapareciendo o aún persiste, ya que algunos efectos calendario en mercados accionarios desarrollados se han ido disipando. Los hallazgos de esta investigación, que se realizó de acuerdo con los tres periodos diferentes definidos en la literatura para analizar el impacto fin de mes, muestran que la mayoría de los países bajo análisis obtienen rendimientos anormales positivos en los días asociados al cambio de mes y también muestran anomalías en la volatilidad. Esta investigación no solamente analiza los índices característicos de cada mercado, sino que también las acciones en particular de cada uno, dotándolo de una muestra mucho mayor y exigente al momento de concluir sobre la existencia del fenómeno. También se incluye un análisis de volumen de transacción para verificar ciertas hipótesis del fenómeno asociadas a mayor flujo de efectivo.

Dinámica de Sistemas aplicada al Mercado de Hidrocarburos Líquidos en España

OpenAIRE

Bozhidarova Vladimirova, Natali

2015-01-01

En primer lugar, en este TFG se trata el mercado de petróleo a nivel mundial, comentando las reservas, la producción y el consumo de petróleo producidos en los últimos diez años, así como, los principales conflictos bélicos sucedidos en la historia, ligados estrechamente al petróleo. En segundo lugar, se aporta información relevante sobre el mercado de hidrocarburos en España, para después, aplicar la Dinámica de Sistemas a este mercado y poder ver la evolución que tendrán las variables princ...

“LAS AUDIENCIAS DE LA CALLE” ENTRE MERCADOS, CALLES Y MÚSICA EN PERÚ

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Franklin Cornejo Urbina

2008-01-01

Full Text Available Cuando se habla de audiencias de los medios de comunicación entendemos también que ellas cambian en los contextos, donde los televidentes y radioescuchas usan los medios con modos y fines diferentes. Así y como parte de la diversidad de las audiencias he ubicado bajo la definición “audiencias de la calle” a un grupo social, más bien de origen humilde y de rutinas cotidianas colectivo-comunitarias, que incluyen a ex campesinos, niños de la calle, comerciantes ambulantes e inmigrantes empobrecidos que se reúnen, trabajan y pasan gran parte del día en mercados de zonas urbano marginales de Lima, en Perú. El mercado popular es un lugar para las grandes mayorías donde hay encuentros y tensiones entre lo urbano y rural por viejas diferencias étnicas, regionales, locales y comunitarias entre andinos y costeños. La pobreza, la urbanización y el crecimiento de las ciudades han convertido al mercado en un lugar de sobrevivencia, trabajo, y un espacio para afrontar la vida de la ciudad. El presente artículo aborda el tema de los estudios de audiencia desde el mercado popular peruano, sus medios y comunicaciones.

Estimación de métricas de riesgo de mercado usando mixturas gaussianas

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Jorge Rosales Contreras

2016-01-01

Full Text Available Los principales modelos financieros para la estimación del riesgo de mercado suponen que los rendimientos de los activos siguen una distribución Normal o se basan en la distribución empírica. Con frecuencia, el supuesto de normalidad se da por hecho; sin embargo, resulta poco realista debido a las características de exceso de curtosis y de asimetría observadas en el comportamiento real de los retornos. En este trabajo presentamos evidencia de que las mixturas gaussianas finitas constituyen un medio eficiente para modelar la distribución de los rendimientos de los activos financieros. Estudiamos el modelo y derivamos expresiones para las métricas usuales de riesgo de mercado. Ilustramos su aplicación calculando métricas de riesgo para una cartera de activos del mercado mexicano, con el modelo propuesto y comparándolas con modelos ampliamente usados en el mercado. Derechos Reservados © 2015 Universidad Nacional Autónoma de México, Facultad de Contaduría y Admi- nistración. Este es un artículo de acceso abierto distribuido bajo los términos de la Licencia Creative Commons CC BY-NC-ND 4.0.

PROGRESO TÉCNICO Y PODER DE MERCADO EN LA INDUSTRIA FARMACÉUTICA

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JOSÉ GALLEGO

2009-01-01

Full Text Available En este artículo se presenta la estimación del poder de mercado en la industria farmacéutica colombiana durante 1982 - 2004. El resultado se compara con las estimaciones realizadas para los Estados Unidos y Finlandia. La conclusión fundamental es la confirmación de la existencia de poder de mercado, al estimarse un índice de Lerner mayor que cero y un markup de Hall mayor que uno; la estimación es equivalente al 0.92 y 0.95 del poder presente en Estados Unidos y Finlandia, respectivamente.

Estudo de mercado: "A satisfação dos franchisados em Portugal"

OpenAIRE

Fialho, Maria Cristina Grilo

2013-01-01

Este relatório de estágio foi realizado no âmbito do Mestrado em Matemática e Aplicações, com especialização em Estatística e Investigação Operacional, da Universidade de Aveiro, e o estágio foi realizado no GEMEO (Gabinete de Estudos de Mercado e Opinião do IPAM). Foram desenvolvidas várias atividades relacionadas com os Estudos de Mercado, e uma dessas atividades é sobre o Franchising, onde se pretende avaliar o perfil e satisfação do Franchisado em Portugal. Para isso, fo...

Riesgos sistémicos en el mercado interbancario en Venezuela, 2004-2014

OpenAIRE

Pagliacci, Carolina; Peña, Jennifer

2017-01-01

Este trabajo muestra la aplicación del modelo núcleo-periferia para medir dos dimensiones del riesgo sistémico en el mercado interbancario venezolano: conectividad y patrones de fondeo entre bancos. El período de estudio es de interés porque contiene un episodio de ajuste financiero en el año 2009. Los resultados muestran que posterior a esta fecha, la conectividad del mercado parece haberse reducido, lo que podría redundar en menor riesgo sistémico de contagio. En contraposición, los patrone...

El Outsourcing en la dinámica de sistemas hacia mercados extranjeros

OpenAIRE

Beltrán Segura, Jaime Andrés; Romick Rodríguez, John David; Velásquez Sarasty, Oscar Andrés

2014-01-01

Este trabajo recopila literatura académica relevante sobre estrategias de entrada y metodologías para la toma de decisión sobre la contratación de servicios de Outsourcing para el caso de empresas que planean expandirse hacia mercados extranjeros. La manera en que una empresa planifica su entrada a un mercado extranjero, y realiza la consideración y evaluación de información relevante y el diseño de la estrategia, determina el éxito o no de la misma. De otro lado, las metodologías considerada...

High-resolution carbonate isotopic study of the Mural Formation (Cerro Pimas section), Sonora, México: Implications for early Albian oceanic anoxic events

Science.gov (United States)

Madhavaraju, J.; Lee, Yong Il; Scott, R. W.; González-León, C. M.; Jenkyns, H. C.; Saucedo-Samaniego, J. C.; Ramasamy, S.

2018-03-01

The 420-m thick stratigraphic section of the Mural Formation that is exposed in the Cerro Pimas area of northern Sonora, Mexico, is composed of limestone lithofacies ranging from bioclastic wackestone to boundstone, whose biota is characterized by low diversity. Prominent age-diagnostic fossils are benthic foraminifera and long-ranging calcareous algae that indicate the Aptian/Albian boundary is close to the base of the Los Coyotes Member. The carbonates of this formation have negative to positive δ13C values (-4.63 to +2.6‰) and highly depleted δ18O values that range from -12.74 to -8.34‰. The absence of correlation between δ13C and δ18O values supports a primary marine origin for the δ13C values of these limestones. The carbon-isotopic curve of the Cerro Pimas stratigraphic section has well-defined δ13C segments (C8 - C15) that compare with published curves of similar age. In the lower part of the early Albian Los Coyotes Member, the presence of OAE 1b is indicated by an increase followed by a decrease in δ13C values, suggesting correlation with the Kilian Event. The middle part of the Los Coyotes Member has a significant negative carbon-isotope excursion correlated with the globally recognizable early Albian Paquier event. Moreover, another significant negative carbon-isotope shift is observed in the upper part of the Los Coyotes Member, which can be correlated with the Leenhardt Event. The occurrence of the Kilian, Paquier and Leenhardt Events (OAE 1b cluster) in the Cerro Pimas stratigraphy confirms the global nature of these early Albian disturbances of the carbon cycle.

Análisis de métodos de sanción de precios en el Mercado Eléctrico Mayorista

OpenAIRE

Salazar Coba, Paúl Rigoberto; Argüello Ríos, Gabriel

2005-01-01

Este trabajo presenta distintos métodos de cálculo de los precios de energía en el mercado eléctrico mayorista, considerando un modelo basado en costos. Luego analiza el modelo económico-financiero del mercado eléctrico ecuatoriano en las actuales condiciones y de acuerdo a la normativa vigente. Así mismo, analiza los efectos que provocaría en el mercado, el cálculo del precio de la energía utilizando un modelo multinodal o uninodal. Además analiza el impacto en el mercado de energía de la ut...

Efeito da crise de 2007/2008 na transmissão internacional de volatilidade no mercado de capitais brasileiro

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Marcelo Brutti Righi

Full Text Available Com a crescente globalização, os mercados financeiros do mundo todo passaram a apresentar maior integração. Tal relacionamento entre mercados possui como implicação um termo que vem atraindo a atenção de profissionais e acadêmicos, a transmissão de volatilidade. Dessa forma, o presente trabalho tem como escopo analisar a transmissão internacional de volatilidade no mercado brasileiro. Para tanto, é utilizado um modelo Garch multivariado com parametrização BEKK. Com base nesse modelo, são estimados os relacionamentos bivariados entre o mercado brasileiro, representado pelo índice Ibovespa, e os mercados americano, argentino, mexicano e chinês, utilizando-se de índices representativos de 4 de janeiro de 2000 até 31 de março de 2010, totalizando 2667 cotações. A amostra foi dividida em três partes, representando os períodos anteriores, durante e posteriores à crise do subprime de 2007/2008. Os resultados obtidos permitem concluir que, durante a crise de 2008, de forma geral, houve mudança na direção da transmissão de volatilidade entre o mercado brasileiro e os demais estudados, de forma ao Brasil passar a exercer maior influência na volatilidade condicional desses, por ter sofrido menores consequências com a crise financeira. Além disso, após o período de turbulência causado pela crise de 2008, o relacionamento da volatilidade entre o mercado brasileiro com os demais passou a ser menos assimétrico do que no período anterior a crise.

Concentración y precios en el mercado mundial de aceite de palma 1985-2005

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Jorge L. Navarro España

2013-07-01

Full Text Available El presente trabajo estudia la estructura del mercado mundial de aceite de palma, así como la in"uencia de dicha estructura sobre el nivel de precios. Para ello se hace uso del cálculo de índices de concentración de mercado y de estadísticos correlaciónales para establecer relaciones de causalidad. Los principales resultados muestran que a pesar que este mercado está fuertemente concentrado, esto no parece tener efectos sobre los precios. La explicación dada a esta situación es que se da por la alta sustitución entre los aceites de palma, girasol y soya, así como al hecho que las barreras de entrada no son los su#cientemente altas.

El estado del arte de la orientación al mercado en las organizaciones culturales

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José Ignacio Azuela Flores

2014-01-01

Full Text Available Desde hace tiempo se han desarrollado diversas investigacio - nes centradas en determinar la contribución de la orientación al mercado en los resultados empresariales. Sin embargo, el estudio del efecto de la orientación al mercado en el desem - peño de las organizaciones culturales representa un área de investigación incipiente. Atendiendo a esta situación, nuestro trabajo tiene como principal objetivo realizar una revisión de los aspectos esenciales de la orientación al mercado en las or - ganizaciones no lucrativas, específicamente en organizaciones culturales; asimismo, identificar futuras líneas de investigación que permitirán contribuir en este campo de estudio aún fértil.

Sistema de producción flexible de productos manufacturados para un mercado globalizado

OpenAIRE

Acuña Pinaud, Leoncio Luis; Acuña Pinaud, Leoncio Luis

2008-01-01

El presente trabajo de investigación tiene por objetivo el diseño de un Sistema de Producción Flexible de productos manufacturados paraun mercado globalizado a partir del enfoque de sistemas según las características identificadas de las experiencias obtenidas de las empresas. Las alternativas tecnológicas que se presentan para los productos de manufactura metalmecánica contribuye a la exigencia de los certificados de calidad que el mercado global demanda. A partir del trabajo de campo realiz...

Emplacement and geochemical evolution of eocene plutonic rocks in the Colville batholith

International Nuclear Information System (INIS)

Holder, R.W.

1986-01-01

Eocene plutonic rocks in the Colville batholith are divided on the basis of field evidence and chemical composition into, in order of decreasing age, (1) several calc-alkalic biotite-hornblende monzodiorite to granodiorite intrusions referred to as the Devils Elbow suite, and (2) compositionally variable calc-alkalic to alkali-calcic intrusions referred to as the Herron Creek suite. These Eocene suites are distinct from older, more voluminous, leucocratic granite and granodiorite intrusions, designated the Keller Butte suite, which are calcic and characteristically lack hornblende. Results of qualitative and computer modeling of major element variation and quantitative models of trace element variation in the chemically coherent Bridge Creek intrusions, a member of the Herron Creek suite, are compatible with fractionation of plagioclase feldspar + hornblende + biotite + magnetite + apatite from a parent magma of andesitic composition to account for the observed variation. Strongly curved variation trends preclude mixing as the primary mechanism for the observed variation. It is suggested that parallel variation trends in the other Eocene intrusions are also the result of crystal fractionation. Lateral chemical variations including a decrease in silica saturation suggest the chemical characteristics of these rocks reflect those of parental magmas derived from the mantle, with an unknown amount of crustal contribution. Rotated and angular xenoliths, discordant contacts, and temporal and spatial proximity to graben structures indicate that the Eocene plutons were passively implaced into the upper crust along graben-bounding faults during graben formation, the earlier stages of which appear to have been contemporaneous with regional mylonitic deformation

Mercado/Robb/Buchdahl coefficients: an update of 243 common glasses

Science.gov (United States)

Bolser, Michael

2002-12-01

The 1983 Mercado/Robb listing of Buchdahl chromatic coordinate coefficients is supplemented with glasses from the Schott and O'Hara catalogues. The coefficients were calculated by using Buchdahl's cubic model. Appropriately selected materials yield a superachromat.

Criterios para la fijación del valor de las acciones negociables en el mercado de capitales

OpenAIRE

Martinez Caraballo, Hugo Ramon; Jimenez, Edison E.M.

2009-01-01

El objetivo del trabajo fue, determinar los criterios para la fijación del valor de las acciones negociables en el mercado de capitales, a raíz de la aparición de nuevos factores de riesgo. Para ello, se caracterizo el mercado de capitales en Venezuela. Se determino los principales indicadores económicos y de mercado bursátil para la fijación del valor de las acciones. Se distinguió los factores de riesgo que engloban la fijación del valor de las acciones y las características del contexto p...

Bio-sociodiversidade: preservação e mercado

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Mauro Leonel

2000-04-01

Full Text Available VÁRIOS estudos vêm revelando possibilidades de aproveitamento de conhecimentos indígenas e de outras culturas tradicionais, entre eles, medicamentos, cosméticos, novos materiais, alimentos, sementes e conservantes como produtos de mercado. A prática do mercado vem sendo a de apropriar-se desses bens culturais, registrá-los após adaptações e devolvê-los como mercadorias protegidas por patentes, inclusive aos países onde tais conhecimentos foram desenvolvidos, geralmente ao sul do Equador. Frente à escala da degradação social e ambiental, como na Amazônia, surgiu um novo otimismo, o de que resultados financeiros de tais produtos pudessem reverter às populações, modificando-se a legislação internacional e associando-se cooperativas de produtores com a biotecnologia e as transnacionais. O mercado, o principal adversário da preservação da bio e da sociodiversidade, seria assim convidado - empresas e consumidores - a tornar-se aliado da manutenção da floresta em pé e da diferença cultural, por exemplo, mediante certificados de origem. No entanto, são numerosos os entraves para que essas populações possam abrir brechas no mercado, ou nos sistemas internacionais de registro de patentes, frente à lógica da concentração de capital e tecnologia.SEVERAL studies have been revealing prospects of capitalizing on native knowledge and traditional cultures in order to launch new market products, such as drugs, cosmetics, new materials, foods, seeds and preservers. The market has adopted the practice of appropriating such cultural goods, which after slight adaptation are registered and turned out as patent-protected products and sold even to the countries where that knowledge was first developed, south of the equator as a rule. Vis-à-vis the social and evironmental degradation scale, as is the case of the Amazon area, a new optimism has risen: the hope that financial results from such products could benefit the native peoples

Suministro de información y seguros de confiabilidad en el mercado SPOT de generación de electricidad colombiano.

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David Fernando Tobon O.

2010-05-01

Full Text Available Este artículo tiene como objetivo presentar algunos mecanismos de mercado que pueden inducir a mejorar la confiabilidad en el mercado de generación de electricidad spot colombiano; estos son:1 la provisión de información adicional al precio unitario spot, en un mercado que por su naturaleza es aleatorio, y 2 seguros de confiabilidad, al reconocerse que las demandas son altamente inflexibles. También se desarrolla una aplicación para mostrar cómo operarían en la práctica estos mecanismos y se determinan las restricciones que se deben corregir para que sean operativos. Este programa de seguros garantiza una confiabilidad eficiente, provee información importante para los agentes del mercado y reglas de asignación que minimizan los costos económicos en caso de fallas en la capacidad de generación de electricidad, que podrían ser aplicados a mercados de generación de electricidad como el colombiano, donde se han tenido recurrentes crisis de abastecimiento y se ha pensado profundizar en las reformas de este mercado.

Custo de capital próprio em mercados emergentes: uma abordagem empírica no Brasil com o downside risk

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Graziela Xavier Fortunato

2010-02-01

Full Text Available Este artigo visa testar empiricamente a proposta de Estrada (2000 para as empresas que compoem o Ibovespa, avaliando se para mercados emergentes existem outras medidas de risco sistematico diferentes do beta do capital asset pricing model (CAPM. Dessa forma, testou-se o downside risk que capta a parte negativa do retorno. Alem de dados em cross section, utilizaram-se dados em painel, como uma contribuição adicional ao trabalho de Estrada (2000. Os resultados encontrados não confirmam que o downside risk seja uma medida apropriada ao mercado brasileiro. Outras medidas de risco apresentaram melhor correlacao com o retorno, permitindo o calculo do custo de capital com valor diferente daquele obtido pela aplicacao do beta. De acordo com Estrada (2000, os resultados sugerem que os mercados emergentes estao em posicao intermediaria entre os mercados integrados e segmentados, tal como confirmado para o mercado brasileiro.

Early Paleozoic dioritic and granitic plutons in the Eastern Tianshan Orogenic Belt, NW China: Constraints on the initiation of a magmatic arc in the southern Central Asian Orogenic Belt

Science.gov (United States)

Du, Long; Long, Xiaoping; Yuan, Chao; Zhang, Yunying; Huang, Zongying; Sun, Min; Zhao, Guochun; Xiao, Wenjiao

2018-03-01

Early Paleozoic dioritic and granitic plutons in the Eastern Tianshan Orogenic Belt (ETOB) have been studied in order to constraint the initiation of a magmatic arc formed in this region. Zircon U-Pb dating indicates that two dioritic plutons in the northern ETOB were generated in the Late Ordovician (452 ± 4 Ma) and the Early Silurian (442 ± 3 Ma), respectively. Diorites from the two plutons are characterized by enrichments in large ion lithophile elements (LILE) and highly incompatible elements, with depletions in high field strength elements (HSFE) displaying typical geochemical features of a subduction-related origin. They have positive εNd(t) values (+5.08-+6.58), relatively young Nd model ages (TDM = 0.71-1.08 Ga), with Ta/Yb (0.05-0.09) and Nb/Ta ratios (12.06-15.19) similar to those of depleted mantle, suggesting a juvenile mantle origin. Their high Ba/La (13.3-35.9), low Th/Yb (0.72-2.02), and relatively low Ce/Th (4.57-14.7) and Ba/Th (47.8-235) ratios indicate that these diorites were probably produced by partial melting of a depleted mantle wedge metasomatized by both subducted sediment-derived melts and slab-derived aqueous fluids. Zircon U-Pb dating of a granitic pluton in the northern ETOB yielded a Late Ordovician intrusion age of 447 ± 5 Ma. Granites from this pluton show calc-alkaline compositions with geochemical characteristics of I-type granites. They also show positive εNd(t) values (+6.49-+6.95) and young Nd model ages (TDM = 0.69-0.87 Ga), indicating that the granites were most likely derived from juvenile lower crust. Our new dating results on the dioritic and granitic plutons suggest that arc-type magmatism in the northern ETOB began prior to or at the Late Ordovician (452-442 Ma). In addition, north-dipping subduction of the Kangguertage oceanic lithosphere may account for the arc-type magmatism and the geodynamic process of the ETOB in the Early Paleozoic.

Relação entre Valor de Mercado e Ativo Intangível na Bovespa.

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Eduardo de Paula e Silva Chaves

2013-09-01

Full Text Available O valor de mercado das ações das empresas, negociados em bolsa, deve traduzir as expectativas dos investidores. E, muito embora os preços dessas ações estejam sujeitos à lei da oferta e da procura, diferentes métodos de avaliação, que utilizam diferentes indicadores contábeis, dados econômicos e interpretações subjetivas, podem gerar desvios no valor percebido das empresas. Este valor de mercado organizacional é conhecido como o preço da ação multiplicado pelo número das ações presentes para negociação. Esta equidade é uma questão de interesse para gestores contábeis, políticos e investigadores (Choi, 2000. É buscar a predição dos valores de mercado de empresas abertas, a partir das expectativas de valorização por parte dos acionistas. Para tanto é necessário entender a relação existente entre o retorno do ativo intangível e o retorno do valor de mercado das empresas da amostra, utilizada nos últimos cinco períodos, sendo esse o objetivo principal do trabalho. Este trabalho se enquadra numa pesquisa analítica, indutiva e básica (Collis; Hussey, 2005. Compreende uma pesquisa qualitativo-quantitativa na área de administração, finanças coorporativas e mercado financeiro brasileiro (Cherobim, 2003. Assim, responde-se à pergunta de pesquisa com algumas técnicas estatísticas, uma vez que o artigo não abrange todas as possibilidades de relações existentes entre as duas variáveis de forma estatística, mas tem forte capacidade de indicar a não predição do valor de mercado pelos ativos incorpóreos organizacionais. Palavras-chave:   Ativos

Competencia de las prendas de vestir mexicanas en el mercado de Estados Unidos

OpenAIRE

Nadima Simón Domínguez

2004-01-01

El objetivo de este artículo es analizar el comportamiento de las exportaciones del sector de prendas de vestir (de tejido de punto y de tejido plano) en el mercado de Estados Unidos (EUA) durante el periodo de 1990 a 2002. Se identifican los principales competidores, las características de ambos mercados y los instrumentos de política comercial utilizados por las empresas estadounidenses para la protección de su industria textil. De igual forma, se hace un análisis de los princip...

Summary of a Gas Transport Tracer Test in the Deep Cerros Del Rio Basalts, Mesita del Buey, Los Alamos NM.

Energy Technology Data Exchange (ETDEWEB)

Stauffer, Philip H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rahn, Thomas A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ortiz, John Philip [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Salazar, Larry Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Boukhalfa, Hakim [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Snyder, Emily Elisabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2018-01-16

Here we describe results from a tracer test in the Cerros del Rio basalt beneath Mesita del Buey, Technical Area 54 (TA-54) at Los Alamos National Laboratory (LANL or the Laboratory). This report follows from plans outlined in our previous Tracer Test Work Plan (LANL 2016). These activities were conducted by LANL to further characterize subsurface properties of the Cerros del Rio basalts at Material Disposal Area (MDA) L (Figure 1.1-1). The work presented follows from the “Interim Measures Work Plan for Soil-Vapor Extraction of Volatile Organic Compounds from Material Disposal Area L, Technical Area 54, Revision 1,” submitted to the New Mexico Environment Department (NMED) in September 2014 (LANL 2014). Remediation of the MDA L vapor plume by soil-vapor extraction (SVE) is recommended as part of the final remedy in the “Corrective Measures Evaluation Report for Material Disposal Area L, Solid Waste Management Unit 54-006, at Technical Area 54, Revision 2” to meet a remedial action objective of preventing groundwater from being impacted above a regulatory standard by the transport of volatile organic compounds (VOCs) to groundwater through soil vapor (LANL 2011).

La industria musical colombiana en el mercado de los nuevos usos digitales

Directory of Open Access Journals (Sweden)

Juan Carlos Monroy Rodríguez

2006-01-01

Full Text Available Este artículo pone de presente una realidad que está transformando el mercado de la industria fonográfica, discográfica y cinematográfica. En efecto, hoy en día esta industria ha perdido competitividad en un mercado donde es más económico descargar archivos de música de Internet y fijarlos a través de quemadores en soportes físicos o fijarlos en formatos de comprensión digital (MP3, que comprar los soportes físicos que pagan derechos de autor. Con este panorama actual, el artículo propone alternativas para hacer viable un mercado legal de la música y el cine a través de usos digitales, con soluciones como el uso de ringtones y master tones como una de las posibilidades para poner obras musicales a disposición del público a través de usos digitales y así mismo buscar que los titulares de estos derechos puedan obtener un lucro. De otro lado, también se propone la opción de eliminar los soportes o medios físicos y hacer accesibles al público las obras a través de medios digitales, como un downloading oneroso, que requerirá la adopción de medidas tecnológicas que disuadan el downloading gratuito. Finalmente, el artículo rescata la labor que han realizado las sociedades de gestión colectiva en Colombia buscando poner acorde con el mercado a los autores y a los titulares de derechos conexos.

El mercado de la carne de bovino en México, 1970-2011

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Joaquín Cruz Jiménez

2014-01-01

Full Text Available La proteína animal es básica en la dieta de los mexicanos y las fuentes principales son carne de ave, bovina y porcina. En 2011 se consumieron 60 kg/persona de carne; 16.5 kg/persona fue bovino. Para estable- cer y cuantifi car el efecto sobre el mercado mexicano de carne de bovino de sus prin- cipales variables determinantes, se diseñó un modelo econométrico de ecuaciones simultáneas, estimado a través de mínimos cuadrados en dos etapas con información secundaria para el periodo 1970-2011. Se consideró un contexto de economía abierta para el mercado bovino, de costos de pro- ducción crecientes y de pérdida de partici- pación en el mercado nacional. Resultó una oferta inelástica a los cambios del precio al productor y una demanda elástica al precio al consumidor, y el precio de importación de carne y granos inciden sobre la oferta, demanda y el saldo de comercio exterior.

A GEOGRAFIA DO MERCADO MUNDIAL DE PRODUTOS AGROALIMENTARES E O PAPEL DO BRASIL

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Marlon Clovis Medeiros

2014-02-01

Full Text Available O artigo analisa as mudanças recentes na geografia do mercado mundial de produtos agrícolas, discutindo a inserção do Brasil, o papel dos mercados futuros na elevação dos preços internacionais e as mudanças entre os países exportadores e importadores de produtos agrícolas. Argumentamos que a principal mudança no espaço agrícola mundial nas últimas duas décadas foi o crescimento dos investimentos financeiros em commodities agrícolas e o crescimento dos mercados de futuros. A dinâmica financeira se tornou dominante nos mercados agrícolas, levando à mudanças nas safras e nos preços, tornando-os subordinados à expectativa de retorno dos investidores. Este foi o principal elemento da inflação de preços agrícolas em 2006-2008. Estudos dos mais diversos organismos internacionais (FAO, FMI e Banco Mundial apontaram cenários de agravamento da fome em inúmeros países e de continuidade da alta de preços, mas desviaram o foco do papel da especulação, apontando duas grandes causas: a produção de biocombustíveis e o aumento do consumo de alimentos na Ásia. No presente artigo argumentamos pelo contrário, que o papel das vendas antecipadas nas bolsas de mercadorias e futuros, foi o elemento determinante. A oferta e a demanda agrícola vem perderam espaço como reguladores de preços para a antecipação e expectativas dos mercados futuros. Os preços são determinados antes mesmo do plantio. A ampliação dos fluxos internacionais de capital e as crises financeiras trouxeram a dinâmica internacional para o centro dos debates geográficos e sobre os rumos da agricultura.

Liberalización financiera y segmentación de mercados.

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Isabel Dauner.

1998-08-01

Full Text Available En contra de la llamada “Escuela de la Represión Financiera”, este artículo muestra, a partir de la experiencia de Nicaragua, que la liberalización financiera no es una condición suficiente para el desarrollo de un sistema financiero eficiente. En el sector rural nicaragüense no existen mercados financieros capaces de jugar su rol de intermediador entre ahorrantes e inversionistas, sino segmentos de mercado aislados entre sí. En este, como en oros países del continente latinoamericano, encontramos la presencia de un conjunto de limitantes estructurales e institucionales, más adecuadas aún en las zonas rurales, que no son tomadas en cuenta en la planificación de las reformas financieras y que, por ello, impiden que las mismas produzcan el impacto esperado.

HMV Ingenieros Ltda : un modelo de internacionalización para entrar en el mercado Triángulo Norte

OpenAIRE

Marín Cadavid, Carolina

2012-01-01

Esta investigación por medio de un estudio de caso estudia el proceso de internacionalización que debería seguir HMV ingenieros Ltda, con el objetivo de ingresar en el mercado Triángulo Norte. Un paso a paso es el modelo que debe llevarse a cabo como guía para incursionar en dicho mercado. Con la experiencia de HMV Ingenieros Ltda, se concluye que presenta una fortaleza para establecer presencia comercial (modo 3) en el mercado de Triángulo Norte. Adicionalmente acorde con las tendencias de l...

Rare earths, thorium, and other minor elements in sphene from some plutonic rocks in West-Central Alaska

International Nuclear Information System (INIS)

Staatz, M.H.; Conklin, N.M.; Brownfield, I.K.

1977-01-01

Sphene is an abundant accessory mineral in some abnormally radioactive plutonic rocks in west-central Alaska. Seven samples of sphene from four different areas in west-central Alaska contained from 20,350 to 39,180 parts per million total rare earths and 390 to 2000 ppM thorium. The lanthanide content in six of the seven sphenes is chiefly the light rare earths and is similar to that of crystal abundance; a seventh sphene from the Darby Mountains, however, contains above average amounts of the heavy rare earths. A comparison of the lanthanide distribution in sphene from several areas indicates that the structure of sphene will accommodate whatever lanthanides are available when the mineral crystallizes. The amount of thorium and rare earths in sphene is also affected by the presence of other accessory minerals. Sphene in rocks containing either allanite or zircon has a lower thorium content than in rocks that do not contain allanite or zircon. Sphene, because of its abundance, may contain the greater part of the rare earths and thorium in some of the plutonic rocks of west-central Alaska

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.

Caracterización del mercado laboral del sector hotelero del estado Mérida, Venezuela

OpenAIRE

Villasmil R., María A.; Andrade, Henry

2009-01-01

Esta investigación trata sobre modelos que permiten caracterizar Mercados Laborales Locales (MLL), ya que en Venezuela el manejo de los mismos es casi inexistente. En este sentido, se plantea como objetivo caracterizar al mercado laboral del sector hotelero del estado Mérida-Venezuela en función del conocimiento de las particularidades económicas, institucionales, políticas, sociales, educativas y culturales de la zona así como las condiciones que se tengan en materia de empleo, oferta de for...

Recognition of favorable zones for uranium and thorium accumulation, at Um Ara-Um Shilman granitic pluton, south eastern desert, Egypt, using airborne spectrometric and magnetic data

International Nuclear Information System (INIS)

Elkattan, E.M.

1995-01-01

The objective is aimed at identifying significant U and Th anomalies, the amount of re-mobilization of U and Th, the structural framework of the granite pluton and the distribution of spectrometric anomalies. The study revealed that the granite pluton could be represented as a single radio-lithologic unit excluding abnormal measurements exceeding Xban + 2S. It also revealed the existence of eight strong spectrometric anomalies. Observed values of eU correlate well with eTh, r=0.72 while the correlation between eU/eTh and eU is lacking, r=0.190. Meanwhile, there is a negative correlation between eU/eTh and eTh,r= -0.335. This deficiency in correlation suggests a limited or zero remobilization of uranium, which was partly governed by magmatic processes. Most of the radioactive anomalies were found within or near the major contact faults which may act as channels for mineralized fluids from the subsurface. These fluids possess increased concentrations of U and/or Th which could exist in appropriate chemical and/or structural traps. The U and Th anomalies were found to be associated with the northern and southern parts of the granite pluton respectively. The difference between the northern and southern parts of the granite pluton may be attributed to differences in radioelement content, the effect of partial and/or complete digestion of older rocks, or to different levels of erosion. (author)

Discriminación en el mercado laboral por habilidades, educación escolar y género en Chile

OpenAIRE

David Bravo; Claudia Sanhueza; Sergio Urzua

2008-01-01

En este trabajo se analiza el efecto de los niveles de escolaridad sobre las brechas de sexo en el mercado laboral chileno. Se emplea un nutrido conjunto de datos sobre los resultados del mercado laboral, el logro académico y el rendimiento académico, así como las variables que caracterizan los antecedentes familiares. Aunque los resultados muestran diferencias de sexo estadísticamente significativas en varias dimensiones del mercado laboral chileno, esas brechas dependen mayormente del nivel...

¿Qué tan verde es tu mercado?

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Wilmar R. Olaya-González

2011-01-01

Full Text Available El mercado de lo verde y lo ecológico es una tendencia indiscutible en nuestro mundo globalizado, que busca de alguna manera resarcir el daño infringido sobre el medio ambiente. Más allá de simple altruismo, la ecología se ha convertido en una moda, de la cual unos y otros toman ventaja a su mejor acomodo, haciendo del mercado de productos y servicios su tribuna; eco-diseño, planes de responsabilidad social y ambiental, campañas por el reciclaje y consumo de productos "más amigables" con el medio ambiente hacen parte del panorama que se intenta describir en esta reseña. Por medio de un estudio de caso, se hará énfasis en cómo la comunicación asume un papel crucial en la verdadera apropiación del concepto de "consumidor verde" y "consumidor responsable", de manera que la propuesta transversal de las tic se convierta en una herramienta no solo tecnológica, sino también de empoderamiento del papel que la sociedad puede representar en el cuidado de los recursos naturales.

Pinus Culminicola Andresen y Beaman y sus asociaciones en la ladera sur del cerro La Viga, Coahuila

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Rubén Sánchez Silva

1990-01-01

Full Text Available Pinus culminicola was described in 1961 with samples from the Cerro Potosí, State of Nuevo León, Mexico. The species was reported in the Sierras La Marta in 1962, and San Antonio de las Alazanas in 1975, State of Coahuila, indicating that there were not pure associations. In 1979 the species was colected in the Sierra La Viga, Coahuila, at 3 300 m, without data on environmental conditions in which it grows. The distribution of  P. culminicola is restricted to the south slope of the Cerro La Viga. The associations identified and described in this paper are: (1 Scrub of Quercus rugosa – Quercus durifolia – Cercocarpus montanus with elements of P. culminicola; (2 Pinus montezumae–Pseudotsuga macrolepisy with elements of P. culminicola, Quercus spp. and Arbutus xalapensis (3 P. culminicola– Quercus rugosa (both of them as shrubs; (4 P. montezumac–P. macrolepis–Pinus ayacahuite–P. culminicola; (5 pure scrub of P. culminicola; (6 P. culminicola– Dasylirion tezanum (sometimes with Arctostaphylos pungens and Quercus spp., shrublike; (7 Pinus hartwegii–P. culminicola; (8 P. hartwegii with elements of P. macrolepis and P. culminicola; and (9 induced prairie. There are differences in dominance of the species in accordance to the particular characteristics of each place, with presence of herbaceous from high altitudes. The altitude at which these associations occur, varies from 2 900 m to 3 700 m, although isolated elements of P. culminicola–were found at 2 700 m.

Estrategia de inversión optimizando la relación rentabilidad-riesgo: evidencia en el mercado accionario colombiano

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Orlando E. Contreras

2015-10-01

Full Text Available Este trabajo evalúa y contrasta la rentabilidad observada del portafolio de mercado respecto a la que se obtendría mediante un modelo de optimización que maximiza el ratio de Sharpe, usando retornos diarios del mercado bursátil colombiano. A partir de lo anterior, se obtienen 12 portafolios semestrales recomendados para el periodo 2007-2012 que se comparan con los valores reales del Índice de la Bolsa de Valores de Colombia. Los resultados alcanzados evidencian la efectividad del modelo formulado y la no eficiencia del portafolio de mercado observado, toda vez que sus recomendaciones demuestran un desempeño superior al del mercado. Los aportes de este estudio apuntan hacia el potencial de profundización de su análisis para otros escenarios y en la eventual posibilidad de adopción del modelo en decisiones reales de inversión.

Evaluación Integral del Riesgo Volcánico del Cerro Machín, Colombia

OpenAIRE

Leonel Vega Mora; Fernando Javier Diaz

2013-01-01

El volcán Cerro Machín (VCM) se encuentra situado en la Cordillera Central de Colombia. Por la composición 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 y durante mucho tiempo (meses hasta años) una región 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 cer...

Del mercado al instinto (o de los intereses a las pasiones

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Ovejero Lucas, Félix

2000-06-01

Full Text Available En este ensayo se analizan las explicaciones liberales del orden social. A lo largo de la exposición, Ovejero sugiere la conveniencia de revisar dos posturas centrales del liberalismo que mucho tienen que ver con el planteamiento del ¿problema¿ del orden social y su ¿solución¿ a través del mercado. El ¿problema¿ se basa en la idea insostenible de individuo presocial inherente al liberalismo. En el artículo se exponen algunos argumentos para mostrar por qué razón no tiene sentido la pregunta por el ¿fundamento¿ del contrato social. Se sostiene que la sociabilidad no se puede elegir, como tampoco se elige el lenguaje; es decir, tampoco puede explicarse como un resultado de los intercambios o de la negociación de los individuos en el mercado. También se analizan las alternativas posibles para explicar la existencia del cemento social: el vínculo cívico y el vínculo emocional. El artículo termina con un retorno a las pasiones, entendidas en términos de emociones e instintos, como fundamento central para explicar la forma en que el interés personal y el mercado se conjugan para garantizar el orden social.

The Cerro Tololo Inter-American Observatory Summer Student Programs in La Serena, Chile

Science.gov (United States)

Kaleida, Catherine C.; Smith, C.; Van Der Bliek, N. S.; James, D.

2014-01-01

The Cerro Tololo Inter-American Observatory (CTIO) offers positions for U.S. and Chilean student interns during the Chilean summer months of January-March (northern winter semester) at the CTIO offices in La Serena, Chile. CTIO is part of the National Optical Astronomy Observatory (NOAO) of the United States, focused on the development of astronomy in the southern hemisphere. Six undergraduate research assistantships are offered for U.S. physics and astronomy undergraduate students through the NSF-funded Research Experiences for Undergraduates (REU) program. The CTIO-funded Prácticas de Investigación en Astronomía (PIA) program is run concurrently with the REU program, and offers two research assistantships for Chilean undergraduate or 1st or 2nd year masters students, also at the CTIO offices in La Serena, Chile. The CTIO REU and PIA programs provide exceptional opportunities for students considering a career in astronomy to engage in substantive research activities with scientists working at the forefront of contemporary astrophysics. Student participants work on specific research projects in close collaboration with members of the CTIO scientific and technical staff, such as galaxy clusters, gravitational lensing, supernovae, planetary nebulae, stellar populations, star clusters, star formation, variable stars and interstellar medium. The CTIO REU and PIA programs emphasize observational techniques and provide opportunities for direct observational experience using CTIO's state-of-the-art telescopes and instrumentation. The programs run for 10 weeks, from mid-January to the end of March. A two-night observing run on Cerro Tololo and a field trip to another observatory in Chile are included for students of both programs. These positions are full time, and those selected will receive a modest stipend and subsidized housing on the grounds of the offices of CTIO in La Serena, as well as travel costs to and from La Serena. In addition, the students have the

Growth of plutons by incremental emplacement of sheets in crystal-rich host: Evidence from Miocene intrusions of the Colorado River region, Nevada, USA

Science.gov (United States)

Miller, C.F.; Furbish, D.J.; Walker, B.A.; Claiborne, L.L.; Koteas, G.C.; Bleick, H.A.; Miller, J.S.

2011-01-01

Growing evidence supports the notion that plutons are constructed incrementally, commonly over long periods of time, yet field evidence for the multiple injections that seem to be required is commonly sparse or absent. Timescales of up to several million years, among other arguments, indicate that the dominant volume does not remain largely molten, yet if growing plutons are constructed from rapidly solidifying increments it is unlikely that intrusive contacts would escape notice. A model wherein magma increments are emplaced into melt-bearing but crystal-rich host, rather than either solid or crystal-poor material, provides a plausible explanation for this apparent conundrum. A partially solidified intrusion undoubtedly comprises zones with contrasting melt fraction and therefore strength. Depending on whether these zones behave elastically or ductilely in response to dike emplacement, intruding magma may spread to form sheets by either of two mechanisms. If the melt-bearing host is elastic on the relevant timescale, magma spreads rather than continuing to propagate upward, where it encounters a zone of higher rigidity (higher crystal fraction). Similarly, if the dike at first ascends through rigid, melt-poor material and then encounters a zone that is weak enough (poor enough in crystals) to respond ductilely, the ascending material will also spread because the dike tip ceases to propagate as in rigid material. We propose that ascending magma is thus in essence trapped, by either mechanism, within relatively crystal-poor zones. Contacts will commonly be obscure from the start because the contrast between intruding material (crystal-poorer magma) and host (crystal-richer material) is subtle, and they may be obscured even further by subsequent destabilization of the crystal-melt framework. Field evidence and zircon zoning stratigraphy in plutons of the Colorado River region of southern Nevada support the hypothesis that emplacement of magma replenishments into a

O mercado dos detergentes máquina roupa : a pressão promocional

OpenAIRE

Róis, Marta Alexandra Grangeiro

2012-01-01

Projecto de Mestrado em Economia da Empresa e da Concorrência / Classificação JEL: L81, Q51 O presente estudo tem como objetivo principal analisar a evolução da pressão promocional no mercado dos detergentes máquina roupa, com especial ênfase no canal dinâmico. Para tal foi utilizado o modelo de análise estrutural proposto por Porter (1980), mais conhecido pelo modelo das cinco forças. Com base na informação disponível sobre o mercado foram analisadas as cinco forças das quais foi possí...

Proyecto de electrificación y alumbrado de la urbanización "Cerro Belmonte" en Madrid

OpenAIRE

García Galiano, Alejandro

2010-01-01

En primer lugar lo que el lector se encontrará será una Memoria Descriptiva donde se explican los elementos constructivos utilizados y diseñados para cumplir con el objetivo de dotar a la Urbanización “Cerro Belmonte” de Madrid de los servicios de Energía Eléctrica y Alumbrado Público. Los servicios de Energía Eléctrica comprenden: • Redes de Media Tensión • Centros de Transformación • Redes de Baja Tensión • Canalizaciones y arquetas Se contempla la definición de e...

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

OpenAIRE

Alejandro Parra; Oscar Vivas; Francisco Hormaza

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.

Relación entre la Comunicación y su Eficacia de los Programas Sociales del Ministerio de Desarrollo e Inclusión Social en el Cono Norte Distrito de Cerro Colorado, Arequipa, 2016

OpenAIRE

Llanos Mendoza, Daniela Flora

2017-01-01

La presente tesis cuyo enunciado del problema es: Relación entre la comunicación y su eficacia de los programas sociales del Ministerio de Desarrollo e Inclusión Social en el Cono Norte, distrito de Cerro Colorado de Arequipa “2016”; tiene como objetivo: determinar la relación entre la comunicación y su eficacia de los programas sociales del Ministerio de Desarrollo de Inclusión Social en el Cono Norte, Cerro Colorado, Arequipa. Se planteó la siguiente hipótesis para el presente estudio:...

Estrutura do mercado de trabalho metropolitano na região sul do Brasil, em 1995 e em 2005

OpenAIRE

Sampaio,Armando Vaz

2012-01-01

Para melhor compreender as transições que ocorrem no mercado de trabalho, é importante considerar os fluxos de estar empregado, desempregado e fora do mercado de trabalho e as probabilidades envolvidas em função de variáveis socioeconômicas e geográficas. O modelo econométrico utilizado foi o multinomial logit, em que se observou que há diferença de gênero com respeito a estar ocupado e fora do mercado de trabalho, sendo que, para a primeira situação, a probabilidade é maior para o homem e, p...

Plan de Marketing para la implantación de la cadena minorista Día en el mercado italiano

OpenAIRE

Sánchez-Molina Pando, Aarón

2015-01-01

RESUMEN: La empresa Día es una de las principales líderes de la distribución en España que decide estudiar la posibilidad de entrar en el mercado italiano. Está presente en España, Portugal, Brasil, Argentina y China. Tras analizar la situación actual en los mercados en los que se encuentra y la situación del mercado potencial tanto a nivel de macroentorno (PIB, deuda, paro, demografía y salario medio) como de microentorno (competencia, proveedores y clientes), la empresa elaborará un anál...

Neogene Uplift and Exhumation of Plutonic Bodies in the Beni Bou Ifrour Massif (Nador, northeastern Morocco)

Science.gov (United States)

Lebret, Noëmie; Jolivet, Laurent; Branquet, Yannick; Bourdier, Jean-Louis; Jolivet, Marc; Marcoux, Eric

2013-04-01

In Neogene times, the whole Mediterranean Sea was the center of an intense magmatic activity. This post-collisional magmatism produced a large amount of volcanic edifices through the Alpine belts, together with some intrusives. These plutonic bodies can be associated with skarn-type mineralization, well-known in Elba Island or Serifos Island (Cyclades), where they are generally exhumed by detachment faults. In Morocco, the plutons hosted by the Beni Bou Ifrour massif are connected to the biggest skarn-type iron concentrations of the country (production > 60 Mt, reserves ≈ 25 Mt). The purpose of this work is to explain the late uplift of this massif and subsequent exhumation of the intrusives. As a final product of the Africa-Eurasia plate convergence since ca. 70 Ma, the Rif Mountains constitute the westernmost segment of the Mediterranean Alpine belts. In the oriental part of this range, volcanic summits and Paleozoic to Mesozoic massifs outcrop in the surrounding Mio-Pliocene plains. The Beni Bou Ifrour massif, in the Nador province, consists in a dome-shaped folded Mesozoic series (Domerian to Barremian) affected by a slight epizonal regional metamorphism (ca. 14-12 Ma), dislocated by Neogene NE-SW faults and eventually sealed by upper Miocene transgressive sediments. The hosted intrusives (7.58 ± 0.03 Ma; Duggen et al., 2005) are the plutonic equivalents to the potassic calc-alkaline lavas (andesites mainly) from the surrounding "satellite" volcanic massifs. They turn out to stand in higher topographic position than the younger shoshonitic lavas of the neighboring Gourougou stratovolcano (6.12 ± 0.01 Ma; Duggen et al., 2005). Previous studies have attributed this uplift to the action of normal faults (pull-apart basins; Guillemin & Houzay, 1982), thrusting (Kerchaoui, 1985; 1995) or even of a caldeira resurgence (El Bakkali, 1995). To discriminate against those exhumation mechanisms, field work has been performed, coming along with new cross-sections to

Efecto de las estrategias competitivas y los recursos y capacidades orientados al mercado sobre el crecimiento de las organizaciones

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Carmen Berenice Ynzunza Cortés

2013-01-01

Full Text Available Este estudio analiza las relaciones entre las fuerzas de mercado, las estrategias competitivas, los recursos y capacidades orientados al mercado, así como el desempeño organizacional. La investigación se realizó en Pyme del sector industrial del estado de Querétaro, con un muestreo de conveniencia no probabilístico; asimismo, se diseñó un modelo estructural para probar las relaciones entre las variables, las cuales se analizaron con el software AMOS. El tamaño de muestra alcanzado fue de 116 y la recopilación de información se hizo mediante entrevistas. Las fuerzas de mercado, la estrategia competitiva y la orientación a mercado fueron medidas con las escalas de Kohly y Javorsky (1990, Segev (1987 y Narver y Slater (1990. Los ítems para el desempeño organizacional y los recursos de tecnología e innovación fueron diseñados. Los hallazgos prueban que las fuerzas de mercado tienen un impacto grande en la estrategia competitiva, el cual no es significativo sobre los recursos y capacidades, y es negativo respecto al desempeño, medido por el crecimiento organizacional. El efecto de la estrategia competitiva ha sido significativo sobre los recursos y capacidades de orientación a mercado, tecnología e innovación y no significativo respecto al desempeño. Estos recursos y capacidades influyen de manera significativa en el desempeño organizacional. Los resultados de este estudio enfatizan la implementación de estrategias prospectoras y analizadoras, que crean recursos y capacidades que den valor, con beneficios económicos para las empresas, así como los de orientación a mercado, tecnología e innovación. Estos hallazgos son consistentes con los encontrados en otras investigaciones realizadas en otros países.

La hipótesis de los mercados eficientes, el modelo del juego justo y el recorrido aleatorio

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Martínez Barbeito, Josefina

2006-01-01

Full Text Available El planteamiento de que los precios de mercado reflejan total e instantáneamente la información disponible se conoce como “Hipótesis de los Mercados Eficientes” (EMH. Si esto es verdad, implica que los precios del mercado revelarán siempre los valores justos (fundamentales de los títulos y que, en caso de no ser iguales, entonces la diferencia entre ellos es suficientemente pequeña, de modo que, dados los costes de transacción, esta diferencia puede aprovecharse favorablemente. En síntesis, si se cumple la EMH los mercados de títulos estarán en un equilibrio estocástico continuo. El “modelo del juego justo” no presenta diferencia sistemática entre el rendimiento actual del juego y el rendimiento esperado antes del juego. Se cuestiona el paradigma dominante en la investigación sobre la EMH, debido a diversas anomalías y resultados no consistentes, tratando de encontrar un refinamiento del paradigma existente.

Causalidade entre os retornos de mercados de capitais emergentes e desenvolvidos Causality between stock return rates: emerging versus developed capital markets

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Wagner Moura Lamounier

2007-04-01

Full Text Available Utilizando-se de instrumentais estatísticos para a análise de séries temporais, procurou-se verificar as relações entre os retornos dos principais mercados de capitais emergentes e dos principais mercados desenvolvidos. A amostra foi divida em dois períodos: entre 1995-2002 e entre 2003-2005, tendo em vista os momentos distintos dos mercados quanto à vulnerabilidade externa. No primeiro momento, apesar das diversas crises econômicas, verificou-se que apenas o retorno do mercado emergente da Rússia sofreu grandes impactos ante os choques dos retornos dos outros mercados. Entre 2003-2005, no entanto, os retornos de outros mercados emergentes, como o do Brasil e o do México, responderam de forma significativa aos choques nos retornos dos demais mercados analisados.Using statistical instruments for the analysis of time series, - this work aims to verify the relation of returns of stock investments between the main emerging and the developed capital markets. The sample was divided in two periods: 1995-2002 and 2003-2005, in view of their different external vulnerability moments. At the beginning, - in spite of - several economic crises, only Russia’s stock market returns - suffered great impacts, compared with those at other markets’. Between 2003-2005, however, the returns of other emerging markets, as Brazil’s and Mexico’s, answered in a more significant form to the shocks in the returns of other markets.

The age and thermal history of Cerro Rico de Potosi, Bolivia

Science.gov (United States)

Cunningham, C.G.; Zartman, R.E.; McKee, E.H.; Rye, R.O.; Naeser, C.W.; Sanjines, V.O.; Ericksen, G.E.; Tavera, V.F.

1996-01-01

Cerro Rico de Potosi, Bolivia, is the world's largest silver deposit and has been mined since the sixteenth century for silver, and for tin and zinc during the twentieth century, together with by-product copper and lead. The deposit consists primarily of veins that cut an altered igneous body that we interpret to be a dacitic volcanic dome and its underlying tuff ring and explosion breccia. The deposit is compositionally and thermally zoned, having a core of cassiterite, wolframite, bismuthinite, and arsenopyrite surrounded by a peripheral, lower-temperature mineral assemblage consisting principally of sphalerite, galena, lead sulfosalt, and silver minerals. The low-temperature assemblage also was superim-posed on the high-temperature assemblage in response to cooling of the main hydrothermal system. Both the dacite dome and the ore fluids were derived from a larger magmatic hydrothermal source at depth. The dome was repeatedly fractured by recurrent movement on the fault system that guided its initial emplacement. The dome was extruded at 13.8 ?? 0.2 Ma (2??), based on U-Th-Pb dating of zircon. Mineralization and alteration occurred within about 0.3 my of dome emplacement, as indicated by a 40Ar/39Ar date of 13.76 ?? 0.10 Ma (1??) for sericite from the pervasive quartz-sericite-pyrite alteration associated with the main-stage, high-temperature, mineralization. The last thermal event able to reset zircon fission tracks occurred no later than 12.5 ?? 1.1 Ma (1??). as indicated by fission-tract dating. Minor sericite. and magmatic-steam alunite veins, were episodically formed around 11 Ma and between 8.3 and 5.7 Ma; the younger episodes occurring at the time of extensional fracturing at Cerro Rico and widespread volcanism in the adjacent Los Frailes volcanic field. None of these younger events appear to be signific-ant thermal/mineralizing events: the exceptionally flat thermal release pattern of 39Ar from sericite and the results of the fission-tract dating of

Estimación de las imperfecciones en los mercados de madera: caso de estudio del Pacífico Sur colombiano

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Sandra Rodríguez

2005-12-01

Full Text Available Este artículo estima el grado y naturaleza de las imperfecciones en los mercados de madera del Pacifico Sur colombiano. Los mercados son descritos bajo el paradigma de la organización industrial (estructura/conducta/desempeño. El artículo también incluye un modelo econométrico que estima el grado de la imperfección. Las estructuras de los mercados indicaron altos niveles de concentración de los vendedores. Estos niveles de concentración son el resultado de la presencia de barreras para entrar en el mercado, las cuales son asociadas con falta de acceso a información y capital, deficiencias en el sistema bancario, integración vertical de los participantes, disponibilidad de transporte, y algunas restricciones institucionales. Las imperfecciones de los mercados de maderas crean desigualdades en la distribución del ingreso, desempleo, y pobreza regional. Como consecuencia la contribución de la industria maderera en el progreso socioeconómico es limitada y produce impactos negativos en la conservación de los ecosistemas forestales.

U-Pb geochronology of Gangdese (Transhimalaya) plutonism in the Lhasa-Xigaze region, Tibet

International Nuclear Information System (INIS)

Schaerer, U.; Allegre, C.J.; Paris-6 Univ., 75; Paris-7 Univ., 75; Xu, R.H.

1984-01-01

A series of different plutons from the Lhasa-Xigaze segment of the Gangdese (Transhimalaya) belt has been studied by high-resolution U-Pb analyses of zircon (using zircon fractions of 5-100 grains each, selected upon specific grain characteristics). For two diorites, located east of Xigaze (Dazhuka), the zircons yield concordant ages of 93.4 +- 1.0 and 94.2 +- 1.0 m.y., respectively. Also concordant ages of 41.1 +- 0.4 and 41.7 +- 0.4 m.y. have been obtained for two granodiorites, collected southwest of Lhasa (Qushui). The precision on the ages of two granites from the Xigaze and Lhasa area, is limited by two factors: the presence of inherited radiogenic lead and the occurrence of subsequent lead loss. However, some concordant zircons, detected in both granites, define approximate ages of about 67 and 53 m.y., respectively. The inherited lead components show the melting of Precambrian material was involved in magma genesis. The U-Pb ages substantiate a magmatic activity lasting from mid-Cretaceous (Cenomanian) to Eocene (Lutetian) time. Such a period of plutonism at the southern margin of Eurasia, as well as the occurrence of magma generation from continental crust, suggest that the Gangdese range results from the subduction of Tethys oceanic lithosphere (Indian plate) underneath Eurasia (Eurasian plate). If this model is true, the collision of India with Eurasia (Along the Lhasa-Xigaze sector) postdates the emplacement of the 41 m.y. old Gangdese granodiorites, i.e. the collision occurred after Lutetian time. (orig.)

The Merensky Reef in the Chineisky Pluton (Siberia)? A myth or a reality?

Science.gov (United States)

Zhitova, L.; Sharapov, V.; Zhukova, I.

2006-12-01

It is a dream of each geologist to find a `Merensky Reef' in each layered basic intrusion. Scientists have been trying many various techniques to come this dream to reality. The most perspective way to do so is probably a combination of physicochemical and computer modeling of layered basic intrusion crystallization together with fluid and melt inclusions studies in situ. This combination allows us to do the following: 1. To study boundary conditions for separation of low density gas phase and salt melt from the crystallizing primary basic melt in large magma chamber. 2. To determine correct quantitative parameters for formation of residual fluid-bearing brines extracting high metal concentrations. 3. To compute critical levels for substance differentiation at phase, geochemical and other `barriers' in those basic mantle-crust ore magmatic systems. 4. To model metal extraction, transportation and deposition at these `barriers' for systems of various `silicate melt - residual salt brines' ratios under the conditions of continental lithosphere. Comparison of real and modeled data allows us to conclude if a formation of a narrow zone of high metal concentration is possible at those critical levels (phase and geochemical `barriers'). The above-mentioned algorithm has been used for the Chineisky Pluton (the Transbaikal region, Siberia). Fortunately we have found our own `Merensky Reef', which happened to be a PGE enrichment marginal zone of the Chineisky Pluton due to specific fluid regime of crystallization! This work was supported by the Ministry for Russian Science and Education, Grant #DSP.2.1.1.702.

Progreso técnico y poder de mercado en la industria farmacéutica

OpenAIRE

GALLEGO, JOSÉ

2010-01-01

En este artículo se presenta la estimación del poder de mercado en la industria farmacéutica colombiana durante 1982 - 2004. El resultado se compara con las estimaciones realizadas para los Estados Unidos y Finlandia. La conclusión fundamental es la confirmación de la existencia de poder de mercado, al estimarse un índice de Lerner mayor que cero y un markup de Hall mayor que uno; la estimación es equivalente al 0.92 y 0.95 del poder presente en Estados Unidos y Finlandia, respectivamente....

Segmentación del mercado laboral venezolano desde una perspectiva de género

OpenAIRE

Muñoz de C., Samaria V.; Pinilla, Bernarda

2014-01-01

Este trabajo analiza la segmentación del mercado laboral venezolano a través de la metodología del Análisis de Correspondencia Múltiple para el año 2009. Los resultados muestran que el género y la educación universitaria son elementos segmentadores del mercado laboral en cuanto a: grupo de ocupación, rama de actividad, sector de ocupación, tamaño de la empresa y el nivel de ingreso. Se muestra que en Venezuela el invertir en capital humano incrementa las posibilidades de accede...

Prioridades de Clientes de los Mercados de los Agricultores

OpenAIRE

Curtis, Kynda; Gumirakiza, J. Dominique

2014-01-01

Los mercados de los agricultores ofrecen una experiencia de compra alternativa, especialmente para aquellos consumidores que buscan productos agrícolas frescos, de alta calidad y saludables (Holloway y Kneafsey, 2000; Brown, 2001; Archer et al., 2003; McGarry-Wolf et al., 2005; Zepeda y Deal, 2009; Lyon et al., 2009; Cole 2010; y USDAAMS, 2011).

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.

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

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Mariano Bonomo

2014-10-01

Full Text Available In this paper the results of the studies carried out on ceramic and bone materials recorded at Cerro Tapera Vázquez site (Argentinean Northeast are presented. Taxonomic, anatomic and taphonomic studies of bone assemblages and technological-decorative analysis and refitting of pottery were undertaken. The site is located on a mound next to El Ceibo Creek, where 16 m2 were excavated in 2008. Abundant smooth, incised and modeled pottery (handles and zoomorphic appendages and numerous bones remains of Myocastor coypus (most frequent taxon, Blastocerus dichotomus, Ozotoceros bezoarticus, Cavia aperea, Leopardus geoffroyi, Lycalopex gymnocercus, Hydrochaeris hydrochaeris, birds and fish (Siluriformes and Characiformes were recorded. Except Cavia aperea rodent and Dusicyon gimnocercus fox, all taxa show evidence of anthropic modification (cut marks, fresh fractures and burning. Two radiocarbon dates were obtained: 650 and 520 yrs. BP. The results reached in this study lead to the conclusion that the pre-Hispanic populations that occupied Cerro Tapera Vázquez by the end of the Late Holocene were riverine canoe peoples, with complex ceramic technology and subsistence based on hunting of coypu, capybara and cervids, fishing and small-scale horticulture.

Análisis del comportamiento de mercado de la pitahaya (Hylocereus undatus en Costa Rica

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Olman Quirós Madrigal

2010-10-01

Full Text Available La pitahaya (Hylocereus undatus es una planta que pertenece a la familia de las cactaceae, que se puede consumir como fruta fresca o procesada como pulpa; sin embargo, en Costa Rica su uso no está muy difundido, por lo que el mercado meta es la población de origen nicaragüense residente en el país, quienes catalogan el producto como de consumo tradicional o masivo.Es por esto que resulta importante retomar el estudio de los componentes del mercado, en donde se destaca no sólo por ser una fruta con componentes nutricionales que aportan beneficios a la salud humana, sino tambien porque suple una demanda latente y su cultivo puede ser una actividad alternativa para productores de zonas con condiciones agroecológicas adversas. En relación con el abastecimiento del producto en el mercado nacional, se enfatiza que su procedencia es nacional pero principalmente se importa como fruta fresca y pulpa de Nicaragua y, en menor grado, de Colombia.El precio de la pitahaya en el mercado nacional está estrechamente relacionado con los precios de importación, ya que la oferta principal proviene del producto importado, por lo que ha tenido un comportamiento creciente al pasar, de US$0,574 en el año 2003, a US$1,18 por kg en el 2007.

Uma Análise sobre o Mercado Mundial do Biodiesel

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Dario Oliveira Lima

2014-12-01

Full Text Available O combustível fóssil, base da matriz energética mundial, dá sinais de esgotamento das suas reservas e saturação ambiental por causa do aquecimento global. Surgiu assim um novo desafio para a Academia: encontrar um combustível substituto que seja renovável e não emita Dióxido de Carbono. O biodiesel surgiu como potencial substituto do combustível fóssil que se esgotará dentro de 50 anos. O mercado mundial de biodiesel está em expansão e demanda por informações econômicas referentes ao bicombustível. Este trabalho se propõe a realizar um levantamento sobre as informações de mercado do biodiesel e seu desenvolvimento no mundo. Traz informações relativas à produção, à capacidade produtiva e aos incentivos fiscais do biodiesel em diversos países do mundo.

Aplicação da metodologia de preços hedônicos ao mercado brasileiro de vinhos

OpenAIRE

Naslavsky, Flávia Lobo

2010-01-01

Tendo em vista a completa transformação do mercado de vinhos no Brasil ocorrida nos últimos 10 anos, e o seu ainda enorme potencial de crescimento, esta dissertação se propõe a identificar, através da Metodologia de Preços Hedônicos, os preços implícitos de características de rótulo, sensoriais e informativas de vinhos no mercado brasileiro. A análise destes preços, que não são isoladamente transacionados nos pontos de venda, mas que são indiretamente praticados em equilíbrio de mercado, é de...

Petrotectonic characteristics, geochemistry, and U-Pb geochronology of Jurassic plutons in the Upper Magdalena Valley-Colombia: Implications on the evolution of magmatic arcs in the NW Andes

Science.gov (United States)

Rodríguez, G.; Arango, M. I.; Zapata, G.; Bermúdez, J. G.

2018-01-01

Field, petrographic, and geochemical characterization along with U-Pb zircon geochronology of the Jurassic plutons exposed in the Upper Magdalena Valley (Colombia) allowed recognizing distinct western and eastern suites formed in at least three magmatic pulses. The western plutons crop out between the eastern flank of the Central Cordillera and the Las Minas range, being limited by the Avirama and the Betania-El Agrado faults. The western suite comprises a quartz monzonite - quartz monzodiorite - quartz diorite series and subordinate monzogranites. Chemically, the rocks are high-K calc-alkaline I-type granitoids (some reaching the shoshonitic series) with metaluminous of magnesium affinity. Trace-element tectonic discrimination is consistent with magmatism in a continental arc environment. Most rocks of this suite crystallized between 195 and 186 Ma (Early Jurassic, Pliensbachian), but locally some plutons yielded younger ages between 182 and 179 Ma (Early Jurassic, Toarcian). The eastern suite crops out in the eastern margin of the Upper Magdalena Valley, east of the Betania - El Agrado fault. Plutons of this unit belong to the monzogranite series with rock types ranging between syenogranites and granodiorites. They are high-K calc-alkaline continental granitoids, some metaluminous and some peraluminous, related to I-type granites generated in a volcanic arc. Crystallization of the suite was between 173 and 169 Ma (Middle Jurassic, Aalenian-Bajocian), but locally these rocks contain zircon with earlier inherited ages related to the magmatic pulse of the western suite between 182 and 179 Ma (Early Jurassic, Toarcian). The evolution of the Jurassic plutons in the Upper Magdalena Valley is best explained by onset or increase in subduction erosion of the accretionary prism. This explains the eastward migration of the arc away from the trench. Subduction of prism sediments increased the water flux from the subducting slab, decreasing solidus temperatures, therefore

El sector de manufacturas en Guanajuato y su participación en el mercado nacional

OpenAIRE

Roberto Escalante; Horacio Catalán

2011-01-01

El objetivo del presente artículo es identificar los determinantes de la producción de la industria de manufacturas en Guanajuato en tres divisiones: alimentos, autopartes y calzado. Los resultados de las estimaciones econométricas muestran que la industria de autopartes es bastante sensible a las condiciones del mercado externo. La industria de alimentos está muy vinculada al mercado interno. La industria del calzado desde principios de la presente década ha enfrentado una crisis derivada de...

Geochemistry and meaning of the geotectonic position of plutonic rocks from Chapada region, Goias, Brazil

International Nuclear Information System (INIS)

Kuyumjian, R.M.

1989-01-01

In common with other orogenic belts, in which the presence of both, granitic and small basic-ultrabasic intrusions are characteristics of medium-high pressure metamorphic terranes, the geological and geochemical evidences indicate a close relationship between the granitoid, gabbroic and pyroxenitic plutons and the orogenic metabasaltic rocks from the Chapada volcano-sedimentary sequence. The granitoids are tonalitic and, on discriminant diagrams, they plot in the volcanic arc and pre-collisional fields. They display geochemical characteristics similar to the Jamaican oceanic arc-related granities. They show low LIL and HSF element abundances, low (Ta, Nb)/(K, La, etc) ratios and very low concentrations of Th, Hf, K and Y, when compared to patterns of calkaline, alkali-calcic and alkaline-peralkaline granitoids of magmatic arcs. These chemical features are characteristic of immature island arcs mantle-derived intrusives. The Chapada olivine gabbro has a chondrite-normalized spidergram, closely resembling those of island-arc basaltic lavas, the compositions of its coexisting olivine and plagioclase been similar to those from arc-related cumulate gabbros, and therefore, it could be the plutonic equivalent of the arc volcanics in the Chapada region. It is suggested that the evolution of the granitoids and gabbro intrusives from Chapada are related to a process of subduction that occurred in central Brazil during the Brasiliano/Pan-African event. (author) [pt

O MERCADO DE ÓRGÃOS HUMANOS

OpenAIRE

Chaparro, Germán Raúl

2016-01-01

Este artículo tiene como objetivo presentar los argumentos que justifican la incorporación de incentivos financieros para resolver la escasez de órganos necesarios para la realización de trasplantes. Se utiliza el análisis microeconómico convencional y al análisis simplificado del bienestar para identificar los argumentos que justifican la propuesta de crear un mercado de órganos. Se concluye que los incentivos financieros potencialmente podrían incrementar la oferta de órganos y ampliar el r...

Tornos de alfarero protohistóricos del Cerro de las Cabezas (Valdepeñas, Ciudad Real = Protohistoric potter’s wheels in the Iberian archaeological site ‘Cerro de las Cabezas’ (Valdepeñas, Ciudad Real

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Domingo Fernández Maroto

2015-11-01

Full Text Available El yacimiento ibérico del “Cerro de las Cabezas” ha proporcionado cuatro piezas líticas que identificamos como pertenecientes a tornos de alfarero. Este oppidum ya ha sido puesto de manifiesto como un centro productor y difusor de cerámica ibérica. A través del análisis e interpretación de estas piezas y de las referencias obtenidas en otros yacimientos de la Península Ibérica y del Próximo Oriente, hemos podido confirmar que dos de estas piezas corresponden a un mismo torno, por lo que podemos considerar esta circunstancia como excepcional, dado que hasta el momento, en la Península Ibérica solo se tienen noticias de hallazgos de piezas descontextualizadas y dispersas. Nos encontramos así, con el primer torno  protohistórico completo adscrito a una cronología en torno al siglo III a.C.The Iberian archaeological site ‘Cerro de las Cabezas’ has provided four stone pieces that we identify as belonging to potter’s wheels. This oppidum has been revealed as a producer and spreading centre of Iberian pottery. Through the analysis and interpretation of these pieces, as well as the references obtained from other sites in the Iberian Peninsula and the Middle East, we are able to confirm that two of these findings correspond to the same potter’s wheel. As a result, we could take into account this fact as an exceptional circumstance, because, so far, we only know about some scattered pieces taken out of context in the Iberian Peninsula. Consequently, we have maybe found the first complete protohistoric slow potter’s wheel dating from around the third century BC.

La imagen del turismo cultural en Cuba percibida por el mercado español

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Yamilé Pérez Guilarte

2015-06-01

Full Text Available El turismo cultural, percibido no solo como las visitas a sitios y monumentos históricos, sino ampliado al conocimiento de la forma de vida y tradiciones de las poblaciones locales, podría constituir una importante alternativa para Cuba. La presente investigación tiene como objetivos determinar si Cuba es apreciada como un destino cultural desde la perspectiva del mercado español e identificar cuáles son sus elementos distintivos. Por medio de un cuestionario realizado a 400 españoles, se evalúan los dos componentes de la imagen de un destino: el cognitivo y el afectivo. El estudio revela una preferencia por el turismo cultural y señala a la gente, la música, al Centro Histórico de La Habana y el estilo de vida como los elementos distintivos de Cuba. Estos resultados contribuyen a un diseño más efectivo de la promoción turística en el mercado español, aunque se recomienda ampliar el estudio a otros mercados potenciales.

Análise dos co-movimentos entre os mercados de capitais do Brasil e dos EUA

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Daniel Reed Bergmann

2011-01-01

Full Text Available Neste artigo, a teoria de cópulas é utilizada para analisar os co-movimentos entre os mercados de capitais do Brasil e dos EUA. Na finalidade de implementação de uma estratégia de alocação de ativos é importante entender os eventos extremos - tanto os positivos (boom como os negativos (crashes - e seus efeitos sobre os mercados. Os índices de mercado usados são o IBOVESPA e o S&P 500 cobrindo o período de 03/2001 a 04/2007. A aderência aos log-retornos das principais cópulas encontradas na literatura financeira é avaliada. Os seguintes critérios foram escolhidos: o Log-likelihod, o critério de informação de Akaike e o critério de informação bayesiano. Os resultados mostram que a cópula de Joe-Clayton simetrizada é a mais adequada para modelar a estrutura de dependência entre os log-retornos do IBOVESPA e os do S&P500. Este trabalho difere de alguns estudos já realizados [e.g. Mendes e Moretti(2005 e Canela e Collazo(2005], pois leva em consideração a modelagem de cópulas dinâmicas introduzida por Patton (2006. Finalmente, através dos índices de dependência caudal ao longo do tempo, pode-se concluir que a ocorrência de eventos extremos negativos (crashes no mercado norte americano tende a afetar mais o mercado brasileiro quando da comparação da ocorrência dos eventos extremos positivos (booms.

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

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María Dolores Gómez Moreno

2009-01-01

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

Balance y características del mercado de trabajo y generación de empleo en Colombia 2002-2010

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Roberto Mauricio Sánchez Torres

2013-06-01

Full Text Available Este artículo presenta un balance enmateria de empleo y mercado de trabajo en Colombia en el período 2002-2010, dando especial relevancia al trabajo informal, independiente y por cuenta propia, por su trascendencia en la reciente evolución del mercado laboral. El estudio se enfoca en el análisis de las cifras de este mercado, que ofrece el Departamento Administrativo Nacional de Estadística DANE, y, a partir de los resultados, se plantea que los rasgos principales del desarrollo reciente del empleo en Colombia son su informalidad e independencia.

ANÁLISE DE MERCADO COMO FERRAMENTA PARA O TERCEIRO SETOR

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Grazielle Rigotti da Silva

2012-04-01

Full Text Available O foco dessa pesquisa consiste em identificar, através do estudo de caso, como o processo de Análise de Mercado como ferramenta de escolha de canal de marketing, pode ser um instrumento estratégico também adequado para o êxito no desenvolvimento profissional de instituições do terceiro setor, particularmente àquelas voltadas à área educacional, tratadas especialmente aqui.  Sendo assim, partindo de uma minuciosa pesquisa de mercado em quatro cidades onde atua a Sagrado: Rede de educação, relacionando os temas Marketing, Sustentabilidade e técnicas de Análise de Mercado, e concluindo com o método da Pontuação Ponderada como facilitador da visualização e tomada de decisão, vislumbra-se que as conclusões alcançadas possam auxiliar no planejamento não só da organização apresentada, encontrando soluções que visem a superação dos obstáculos e dificuldades encontradas, mas que seja um impulso a todas as quais se revelam semelhantes à apontada. Parte-se da realidade de que entre os principais obstáculos ao desenvolvimento destas instituições, destacam-se: a carga histórica ligada à pura filantropia, a gerência por intuição, o desconhecimento de técnicas administrativas e a sobrecarga de trabalhos exercida pelos dirigentes, focados mais em atividades fins, do dia-a-dia da empresa. Estes, entre outros fatores, acabam por ocasionar uma elevada taxa de falência entre estas organizações.

Segmentação de mercado no ramo de agências de comunicação Segmentación de mercado en el ramo de agencias de comunicación Market segmentation in the sector of communication agencies

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Aléssio Bessa Sarquis

2009-06-01

Full Text Available Este artigo tem por objetivo discutir e analisar a segmentação de mercado pelas organizações de serviços. Para isso, faz um levantamento bibliográfico a respeito do assunto e apresenta como aplicação prática a segmentação das agências de comunicação. Foram investigados os seguintes assuntos: estratégia de abordagem de mercado, sistemática de identificação de segmentos, sistemática de seleção de mercados-alvo e gestão da compatibilidade entre os clientes. A coleta de dados primários foi realizada por meio de pesquisa exploratória, de cunho qualitativo. Investigaram-se oito das principais agências de comunicação do Estado de Santa Catarina. Os resultados mostram que a maioria das agências de comunicação estudadas adota segmentação e seleção de mercados, mas carece de sistemáticas de aplicação mais estruturadas e de maior esforço na implementação dessas estratégias.Este artículo tiene por objetivo discutir y analizar la segmentación de mercado por las organizaciones de servicios. Para eso hace un levantamiento bibliográfico a respecto del tema y presenta como aplicación práctica la segmentación de las agencias de comunicación. Fueron investigados los siguientes temas: estrategia de enfoque de mercado, sistemática de identificación de segmentos, sistemática de selección de mercados-meta y gestión de la compatibilidad entre los clientes. La colecta de datos primarios ha sido realizada a través de investigación exploratoria, de carácter cualitativo. Se han investigado ocho de las principales agencias de comunicación del Estado de Santa Catarina. Los resultados muestran que la mayoría de las agencias de comunicación estudiadas adopta segmentación y selección de mercados, pero carece de sistemáticas de aplicación más estructuradas y mayor esfuerzo en la implementación de esas estrategias.Market segmentation by service organizations was analyzed. Literature was surveyed to present the

Indoor radon risk associated to post-tectonic biotite granites from Vila Pouca de Aguiar pluton, northern Portugal.

Science.gov (United States)

Martins, L M O; Gomes, M E P; Teixeira, R J S; Pereira, A J S C; Neves, L J P F

2016-11-01

At Vila Pouca de Aguiar area, northern Portugal, crops out a post-tectonic Variscan granite pluton, related with the Régua-Vila Real-Verín fault zone, comprising three types of biotite granites. Among these granites, PSG granite yield the highest average contents of U, probably due to its enrichment in accessory U-bearing minerals such as zircon. In the proximity of faults and joints, these granites are often affected by different degrees of hydrothermal alteration, forming reddish altered rocks, commonly known as "episyenites". These altered rocks are probably associated to the occurrence of hydrothermal processes, which led to uranium enrichment in the most advanced stages of episyenitization. In these granites, both average gamma absorbed dose rates in outdoor and indoor air are higher than those of the world average. Furthermore, even in the worst usage scenario, all these granites can be used as a building material, since their annual effective doses are similar to the limit defined by the European Commission. The geometric mean of radon activity of 91 dwellings located at the Vila Pouca de Aguiar pluton is 568Bqm(-3), exceeding that of other northern Portuguese granites. Measurements carried out during a winter season, indicate that 62.6% of the analysed dwellings yield higher indoor radon average values than the Portuguese legislation limit (400Bqm(-3)), and annual effective doses due higher than the world's average value (1.2mSvy(-1)). The interaction of geogenic, architectural and anthropogenic features is crucial to explain the variance in the geometric mean of radon activity of dwellings from Vila Pouca de Aguiar pluton, but the role of geologic faults is probably the most important decisive factor to increase the indoor radon concentration in dwellings. Hence, the development of awareness campaigns in order to inform population about the incurred radiological risks to radon exposure are highly recommended for this specific area. Copyright © 2016

Anchoring the landscape: human utilization of the Cerro Gavilán 2 rockshelter, Middle Orinoco, from the Early Holocene to the present

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Kay Scaramelli

Full Text Available Abstract Initial archaeological investigations at Cerro Gavilán 2, a rockshelter located in the Bolívar State of Venezuela, reveal evidence for human activity that spans the Early Holocene to the present. This report summarizes the information obtained through surface collection, limited excavation, and documentation of the surface features and rock art in the cave. Accelerator mass spectrometry (AMS 14C analysis established dates from excavated strata that range between 9250 ± 60 BP to 3440 ± 40 BP, and are associated with a unifacial flake technology and charred faunal and floral remains, whereas surface remains span the known ceramic sequence for the area. Rock art corresponds to distinctive superimposed styles that indicate continual repainting of the cave through time, serving to anchor the site to the landscape for multiple societies inhabiting the region. It is suggested that the shelter may have fulfilled different functions over time and a sequence of seasonal residential, ritual, and funerary activities is proposed. The rich cultural context found in Cerro Gavilán 2 contributes to advances in Amazonian archaeology that are redefining our knowledge of early developments and the complexity of human/environmental interactions in tropical America.

Gestión del agua subterránea en el Barrio Cerro Los Leones de Tandil (Argentina)

OpenAIRE

Rodriguez, Corina Iris; Jacinto, Guillermina; Ruiz de Galarreta, Alejandro; Banda Noriega, Roxana

2010-01-01

En este trabajo se describen y analizan los actores y modos de explotación y uso involucrados en la gestión del recurso hídrico subterráneo en un barrio periférico de Tandil -Cerro Los Leones- (Provincia de Buenos Aires, Argentina), que carece de servicios de agua potable y cloacas. Estudios previos demostraron contaminación química y bacteriológica del agua que pone en riesgo la salud de la población. Se caracterizan los modos de uso y explotación del agua, señalando importantes deficiencias...

Neuromarketing: Nuevas fronteras de la investigación de mercados

OpenAIRE

Sutil Martín, Dolores Lucía

2012-01-01

Conferencia realizada en los "Lunes de Comercio" por la Cátedra de Comercio de la Universidad de la Rioja el día 15 de Octubre de 2012 Muestra las nuevas tendencias de la investigación de mercados con los avances de la neurociencia. Economía de la Empresa

Electrical energy measurement under free market schemes; Medicion de la energia electrica bajo esquemas de libre mercado

Energy Technology Data Exchange (ETDEWEB)

Zapata Garcia, Juan A [Comision Federal de Electricidad (Mexico); Vidrio Lopez, Gilberto; Gomez Lopez, Jose M; Mijarez Castro, R [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

2001-07-01

The energy markets deregulation brings new opportunities and challenges, for the companies of electricity as well as for the consumers. The transaction of electricity in an open market requires of well informed participants to analyze the market conditions, they need to know how much energy is consumed, in what time and in what point of the electrical circuits. The lack of a good measurement system is one of the main barriers that prevent the participants to benefit from the opportunities of an open market. In this article the more representative schemes of measurement of the state of art in schemes of free market are exposed, their technological capacities and technologies behind them. It is also mentioned the measurement facilities, control centers, energy quality and technological tendencies. [Spanish] La desregulacion de los mercados de energia trae nuevas oportunidades y retos, tanto para la companias de electricidad como para los consumidores. La compra-venta de electricidad en un mercado abierto requiere de participantes bien informados para analizar las condiciones del mercado, estos necesitan conocer cuanta energia se consume, en que tiempo y en que lugar de los circuitos electricos. La falta de un buen sistema de medicion es una de las principales barreras que impide a los participantes beneficiarse de las oportunidades de un mercado abierto. En este articulo se exponen los esquemas de medicion mas representativos del estado de la practica en esquemas de libre mercado, sus capacidades y tecnologias detras de ellos. Tambien se habla sobre las instalaciones de medicion centros de control, calidad de energia y tendencias tecnologicas.

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

Energy Technology Data Exchange (ETDEWEB)

Cobo R, J.M.

1981-01-01

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

Zircon U–Pb–Hf isotopic and geochemical characteristics of the Xierzi biotite monzogranite pluton, Linxi, Inner Mongolia and its tectonic implications

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Qing-Bin Guan

2018-03-01

Full Text Available The opening, subduction and final closure of the Paleo-Asian Ocean led to the formation of the Central Asian Orogenic Belt. Controversy has long surrounded the timing of final closure of the Paleo-Asian Ocean. Here we present zircon U–Pb ages and petrological, geochemical and in situ Hf isotope data for the Xierzi biotite monzogranite pluton, Linxi, SE Inner Mongolia. U–Pb dating of zircon by LA-ICP-MS yields a middle Permian emplacement age (268.7 ± 2.3 Ma for the Xierzi pluton that is dominated by biotite monzogranites with high SiO2 (71.2–72.8 wt.%, alkali (Na2O + K2O = 8.05–8.44 wt.%, Al2O3 (14.4–15.2 wt.% and Fe2O3T relative to low MgO contents, yielding Fe2O3T/MgO ratios of 2.87–3.44, and plotting within the high-K calc-alkaline field on a SiO2 vs. K2O diagram. The aluminum saturation indexes (A/CNK of the biotite monzogranites range from 1.06 to 1.19, corresponding to weakly to strongly peraluminous. They are enriched in rare earth elements (REE, high field strength elements (HFSEs; Zr, Hf, and large ion lithophile elements (LILEs; Rb, U, Th. The LREEs are enriched relative to the HREEs, with a distinct negative Eu anomaly in a chondrite–normalized REE diagram. Geochemically, the Xierzi biotite monzogranite is classified as an aluminous A-type granite, with all samples plotting within the A2-type granite field on a Y/Nb vs. Rb/Nb diagram. Zircon εHf(t values and two-stage modal ages of the zircons within the pluton range from +4.80 to +13.65 and from 983 to 418 Ma, respectively, indicating that the primary magma was generated through partial melting of felsic rocks from juvenile crust. Consequently, these results demonstrate that the Xierzi pluton formed under the post-orogenic extensional setting after arc–continent collision in the middle Permian.

The Precambrian/Lower Cambrian pluton from Vila Nova (Central Portugal

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Reis, A. I.M.

2010-06-01

Full Text Available The Vila Nova pluton is a small, Pre-Variscan granitic body that intruded rocks of the Central Iberian Zone near the contact with the Ossa Morena Zone and is affected by several shear zones and faults. Its contact metamorphic aureole is constituted by micaschist with porphyroblasts in the outer zone and hornfels in the inner zone. Small metasedimentar xenoliths are dispersed all over the body. The pluton has a great mineralogical heterogeneity with pronounced variations in muscovite/biotite and plagioclase/microcline contents and is classified as granite, granodiorite or tonalite. It is a leucogranite, highly peraluminous (A/CNK = 1.31 – 1.64, magnesian and calc-alkaline to alkaline-calcic. The variation diagrams show curvilinear trends with silica. Eu/Eu* = 0.47 – 0.77 and there is a slight enrichment in LREE relative to HREE. The normalized diagrams indicated dominantly crustal granite, related to subduction. U-Pb isotopic data of zircon and monazite gives 540-542 Ma age.

El plutón de Vila Nova es un pequeño cuerpo granítico pre-varisco, que intruyó en las rocas de la Zona Centro Ibérica, cerca del contacto con la Zona de Ossa Morena, siendo afectado por varias fallas y zonas de cizalla. Su aureola de metamorfismo de contacto consiste en esquistos con porfiroblastos y corneanas. Pequeños xenolitos metasedimentarios aparecen dispersos por todo el cuerpo granítico. Presenta una gran diversidad mineralógica, con amplias variaciones en las relaciones biotita/moscovita y microclina/plagioclasa, siendo clasificado como tonalita-granodiorita-granito. Se trata de un leucogranito fuertemente peralumínico (A/CNK = 1.31 – 1.64, magnesiano y calco-alcalino a alcalino-cálcico. Los diagramas muestran variaciones curvilíneas con la variación de sílice. Eu/Eu* = 0.47 – 0.77 y hay un ligero enriquecimiento de LREE en relación con HREE. Los diagramas indican que la norma es un granito dominante de la corteza, relacionados con la

Possível reação do mercado brasileiro aos investimentos em P&D.

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Eleuterio Vallelado González

2006-03-01

Full Text Available A importância dos ativos intangíveis é crescente no cenário econômico atual, o que faz com que muitas pesquisas sejam dedicadas a eles. Nesse contexto está a avaliação da capacidade de criação de valor de tais ativos, com destaque para Pesquisa e Desenvolvimento (P&D. Já há muitas pesquisas sobre esse tema nos Estados Unidos, sendo escassa, no entanto, em mercados em desenvolvimento. Este trabalho tem como objetivo apresentar uma pesquisa sobre possível efeito econômico de investimentos em P&D nas empresas brasileiras. Para tanto se fez uma revisão bibliográfica sobre a questão em nível mundial e procedeu-se a uma pesquisa empírica nas empresas brasileiras listadas na Bovespa. Apesar dos baixos níveis de investimentos em P&D encontrados, verificou-se sinal de uma sensibilidade positiva do mercado brasileiro com relação aos gastos das empresas em P&D, o que pode ser um indicativo de que esse mercado considera estes como investimentos capazes de gerar benefícios futuros. Adicionalmente se aponta a necessidade de utilização de outros modelos, bem como também a consideração de outros fatores para amadurecer a questão que tem sido motivo de extensa pesquisa em outros mercados.

Redes alimentarias alternativas en grandes ciudades: los mercados de productores agrarios en Madrid

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Ricardo Méndez Gutiérrez del Valle

2017-01-01

Full Text Available Las redes alimentarias alternativas constituyen una temática de investigación emergente en los estudios urbanos, que cuestiona los modelos dominantes de producción, distribución y consumo de alimentos. Una de sus manifestaciones son los mercados de productores, que ponen en contacto directo a productores periurbanos y rurales con consumidores urbanos, favoreciendo las relaciones de proximidad y los circuitos cortos. El artículo investiga los mercados de productores en Madrid mediante una estrategia multimétodo que combina entrevistas, encuestas y otras técnicas complementarias. Los resultados confirman su diversidad interna, identifican las estrategias de los diferentes actores y delimitan su impacto territorial, mostrando también sus limitaciones.

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

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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.

A Visão da Academia e do Mercado de Trabalho sobre o Ensino da Auditoria

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Jhonatan Hoff

2017-01-01

Full Text Available O objetivo deste trabalho foi identificar a percepção do ensino de auditoria sob o enfoque da academia e do mercado de trabalho, com base na avaliação da importância dada por profissionais e docentes aos principais aspectos conceituais e normativos da área de auditoria. Para alcançar o objetivo proposto, coletou-se a percepção dos docentes responsáveis pela disciplina de auditoria e dos auditores atuantes no mercado de trabalho por meio de um questionário estruturado na forma de uma escala Likert. A amostra da pesquisa compreendeu todas as universidades federais e estaduais que possuem e curso de Ciências Contábeis e todas as empresas de auditoria cadastradas no banco de dados da Comissão de Valores Mobiliários (CVM. As respostas obtidas foram tratadas por meio dos testes não paramétricos de Mann-Whitney e a Correlação de Spearman. Os resultados demonstram, que em, aproximadamente, 75% dos assuntos levantados neste trabalho, a academia tende a corresponder à expectativa que o mercado possui acerca da importância dada a tais conteúdos dentro da disciplina de auditoria. As principais diferenças encontradas dizem respeito a assuntos relacionados ao Assurance Service, Auditoria de Entidades sem Fins Lucrativos, Auditoria de Órgãos Governamentais, Controle de Qualidade e Auditoria de Sistemas de Informação, os quais não recebem a ênfase dentro da academia, de acordo com a perspectiva do mercado. Os resultados aqui apresentados podem ser utilizados para que os professores avaliem a disposição dos conteúdos abordados dentro da disciplina, considerando a relevância atribuída pelo mercado.

Mercado laboral y capital social en un contexto de alta movilidad de fuerza de trabajo.

OpenAIRE

Romo Genoy, Edgardo

2015-01-01

Esta investigación tiene como objetivo principal dar cuenta del mercado laboral y el nivel de capital social en un contexto de alta movilidad de fuerza de trabajo. Para este propósito se toma el caso de estudio en el corregimiento de Chiles, municipio de Cumbal (Colombia) ubicado en la frontera colombo ecuatoriana. En primer lugar se aborda el tema de investigación definiendo el mercado desde la perspectiva de Karl Polanyi, según la cual “el mercado” no se explica únicamente en acontecimiento...

DETERMINANTES Y EFECTOS DEL DESAJUSTE EDUCATIVO EN EL MERCADO LABORAL ECUATORIANO 2007-2012

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Héctor Alberto Botello Peñaloza

2016-10-01

Full Text Available Se estudian las causas y los efectos del desajuste educativo en el mercado laboral ecuatoriano según los microdatos de la encuesta de empleo desde 2007 a 2012 que implementa un modelo de elección discreta y de capital humano. El artículo es el primer estudio sobre la exploración de este fenómeno en el mercado laboral ecuatoriano, que además hace un análisis temporal del fenómeno, para comprobar su naturaleza estrucutural. El desajuste educativo en el mercado laboral ecuatoriano abarca 35 % de la masa laboral donde la sobreeducación es mayoritaria con 22 % y la infraeducación con 13 %. Existe un rendimiento positivo para los años de sobreeducación y una penalización sobre los salarios en el caso de la infraeducación, además se evidencia que el desajuste disminuye a medida que aumenta el tamaño de la empresa y la experiencia del individuo. Estas conclusiones mostraríanque las iniciativas de los observatorios laborales para egresados son un primer paso para conocer las necesidades de las empresas y las competencias que desarrollan los egresados.

COMPORTAMIENTO DE LA ECONOMIA Y DEL MERCADO DE TRABAJO EN COLOMBIA DURANTE EL PERIODO 1950-2005

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Oscar Hernan Muñoz

2008-01-01

Full Text Available Los mercados de trabajo desempeñan diversos papeles en las economías modernas. Por una parte, permiten determinar que tan ecaz es la asignación de recursos laborales y de otros factores indirectos en la sociedad. Por otra, constituyen uno de los principales mecanismos de obtención de ingresos por parte de la población activa. Por ello, los mercados de trabajo están en estrecha relación con la distribución de ingresos y el bienestar de la población en general. Siguiendo estas líneas conceptuales, se exploran las principales características de la economía y del mercado de trabajo en Colombia entre 1950 y 2005. En la primera parte, se investiga la evolución de la estructura económica colombiana, colocando especial atención en el manejo de la política económica y sus implicaciones para los diferentes sectores productivos. En la segunda, se analizan las tendencias del mercado de trabajo y sus situaciones problemáticas. En la tercera, se hace una breve referencia al proceso de transición laboral y, nalmente, en la cuarta parte se avanzan algunas conclusiones pertinentes a la problemática tratada en las tres primeras partes.

Instituições e a informalidade no mercado de trabalho

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Gabriel Ulyssea

2008-09-01

Full Text Available O objetivo deste artigo é desenvolver um modelo que concilie os principais aspectos institucionais relativos à informalidade no mercado de trabalho. Trata-se de um modelo de matching com dois setores, formal e informal, que incorpora os principais tradeoffs que firmas e trabalhadores enfrentam ao decidir em que setor ingressar. O modelo apresenta uma inovação que o torna mais coerente aos principais fatos estilizados e às evidências empíricas mais recentes. Os resultados das simulações de políticas mostram que elevações no seguro-desemprego e reduções no imposto sobre a folha geram impactos positivos, porém reduzidos, sobre os principais indicadores do mercado de trabalho. Ao contrário, uma intensificação da fiscalização governamental leva a significativas reduções da informalidade, mas também provoca uma elevação substancial da taxa de desemprego e uma piora em outros indicadores do mercado de trabalho brasileiro.This paper aims to develop a model capable of reconciling some of the main institutional aspects relative to labor market informality. It is a two-sector, formal and informal, matching model that incorporates the main tradeoffs faced by workers and firms when deciding in which sector they will operate. The model presents an innovation that makes it more coherent with most stylized facts and recent empirical evidence. Policy simulation's results show that increasing unemployment benefits and reducing payroll taxes generate positive, although small effects over labor market indicators. However, intensifying government audition rates implies a substantial reduction of informality rates, but it also causes unemployment to increase and the deterioration of other important indicators in the Brazilian labor market.

DEPENDENCIA ESTRUCTURAL EN LOS MERCADOS BURSÁTILES DE COLOMBIA Y ESTADOS UNIDOS: UNA APROXIMACIÓN USANDO CÓPULAS

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Daiver Cardona Salgado

2012-06-01

Full Text Available Para determinar la dependencia estructural entre los mercados bursátiles colombiano y estadounidense, se usaron las pérdidas de los índices Col20, Dow Jones y Standard & Poors 500 como variables. La metodología desarrollada siguió los lineamientos de los modelos de dinámica multivariados, basados en la cópula y propuestos por Chen y Fan (2006. Se encontró que los dos mercados presentan una moderada dependencia y que, de acuerdo con el modelo CAPM, el riesgo sistemático que comparten es bajo y ofrecen posibilidades de diversificación. Además, se encontró que es baja la probabilidad de que ambos mercados experimenten pérdidas extremas conjuntamente.

Structure, emplacement, and tectonic setting of Late Devonian granitoid plutons in the Teplá–Barrandian unit, Bohemian Massif

Czech Academy of Sciences Publication Activity Database

Žák, J.; Kratinová, Zuzana; Trubač, J.; Janoušek, V.; Sláma, Jiří; Mrlina, Jan

2011-01-01

Roč. 100, č. 7 (2011), s. 1477-1495 ISSN 1437-3254 R&D Projects: GA AV ČR KJB300120702 Institutional research plan: CEZ:AV0Z30120515; CEZ:AV0Z30130516 Keywords : Bohemian Massif * Teplá-Barrandian unit * Variscan orogeny * granite * pluton * subduction Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.342, year: 2011

Zircon U-Pb Ages Chronicle 3 Myr of Episodic Crystallization in the Composite Miocene Tatoosh Pluton, Mount Rainier National Park, Washington Cascades

Science.gov (United States)

Bacon, C. R.; Du Bray, E. A.; Wooden, J. L.; Mazdab, F. K.

2007-12-01

Zircon geochronology of upper crustal plutons can constrain longevities of intermediate to silicic magmatic systems. As part of a larger study of the geochemistry and metallogeny of Tertiary Cascades magmatic arc rocks, we used the USGS-Stanford SHRIMP RG to determine 20 to 28 238U-206Pb ages for zircons from each of 6 quartz monzodiorite (qmd), quartz monzonite (qm), or granodiorite (grd) samples representative of the Tatoosh pluton, and one grd from the nearby Carbon River stock. The 7x12 km composite Tatoosh pluton, discontinuously exposed on the south flank of Mount Rainier, consists of at least 4 petrographic/compositional phases, here termed Pyramid Peak, Nisqually, Reflection Lake, and Tatoosh. These collectively intrude gently folded and weakly metamorphosed basaltic andesite flows and volcaniclastic rocks of the Eocene Ohanapecosh Formation, silicic ignimbrites and sedimentary rocks of the Oligocene Stevens Ridge Formation, and basaltic to intermediate volcanic rocks of the Miocene Fifes Peak Formation. Histograms and relative probability plots of U- Pb ages indicate 2 to 4 age populations within each sample. The weighted mean age of each of the youngest populations (all ±2σ) is interpreted as the time of final solidification: Pyramid Peak qmd (58.5% SiO2) 17.4±0.2 Ma, Nisqually grd (in Paradise Valley; 65.4% SiO2) 16.7±0.2 Ma, Nisqually grd (at Christine Falls; 66.4% SiO2) 17.3±0.2 Ma, Reflection Lake qm (along Pinnacle Peak trail; 66.6% SiO2) 17.1±0.2 Ma, Tatoosh grd (in Stevens Canyon; 67.8% SiO2) 18.2±0.2 Ma, Tatoosh grd (south of Louise Lake; 69.3% SiO2) 19.3±0.1 Ma, and Carbon River grd (68.0% SiO2) 17.4±0.3 Ma. The older Nisqually grd age is indistinguishable from a TIMS zircon age of 17.5±0.1 Ma reported by Mattinson (GSA Bulletin 88:1509-1514, 1977) for grd from a nearby locality. None of the 164 SHRIMP-RG U-Pb ages, including cores, is older than 21 Ma. The relatively small, high-level pluton likely was emplaced and solidified in pulses

Prueba de sesgo sobre rendimientos financieros en el mercado colombiano

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Marisol Valencia

2014-01-01

Full Text Available La caracterización de los rendimientos financieros depende, en gran medida, de su comportamiento probabilístico, el cual puede ser mal ajustado, conduciendo así a malas decisiones económicas relacionadas con valoración de activos, asignación de cartera y/o medición del riesgo de mercado. En este trabajo se propone una prueba que permita determinar el ajuste de los rendimientos del Índice General de la Bolsa de Valores de Colombia (IGBC a las siguientes distribuciones: Normal, Normal Sesgada y T Sesgada. Además, se mide el nivel de sesgo y se compara el desempeño de la prueba propuesta con otra prueba existente, usada únicamente para la detección de asimetría. Se encuentra que la prueba propuesta permite caracterizar los rendimientos del mercado de valores colombiano con una de las distribuciones de probabilidad, a diferencia de la otra prueba, que sólo advierte sobre la existencia de sesgo y no establece la distribución que representa su comportamiento.

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

Science.gov (United States)

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

2005-11-29

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

A fatia de mercado em função do esforço mercadológico

OpenAIRE

Grandis Rojo, Francisco José

1984-01-01

Trata de uma análise dos efeitos das variáveis do Composto Mercadológico sobre a Fatia de Mercado de bens de consumo não duráveis, com base em dados levantados no varejo brasileiro. Aborda as relações entre Fatia de mercado e Composto Mercadológico, utilizando-se de modelos de regressão múltipla, tecendo considerações sobre opções estratégicas para os empresários brasileiros.

Análise comparativa da competividade do Brasil e EUA no mercado internacional da carne bovina

OpenAIRE

Matheus Dhein Dill; Vitor Francisco Dalla Corte; Júlio Otávio Jardim Barcellos; Maria Eugênia Andrighetto Canozzi; Tamara Esteves de Oliveira

2013-01-01

O Brasil e os EUA estão entre os principais produtores mundiais de carne bovina. Entretanto, distorções no mercado alimentar decorrentes da presença de barreiras comerciais podem comprometer a competitividade desses países. O objetivo deste trabalho foi verificar a competitividade da carne bovina brasileira e norte-americana, no mercado internacional, entre 1990 e 2008. Para isso, foi utilizado o Índice de Competitividade Revelada (CR) para inferir sobre os efeitos que subsídios, acordos come...

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

Estudo da Concentração de Mercado ao Longo da Cadeia Produtiva da Soja no Brasil

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Nilson Luiz Costa

2014-12-01

Full Text Available O objetivo da presente pesquisa foi mensurar a concentração de mercado ao longo da cadeia produtiva da soja. A partir dessas informações tornou-se possível avaliar se as estratégias para manter e ampliar o poder de mercado e a governança ao longo da cadeia produtiva da soja resultam em sucesso, captação do excedente do produtor rural de soja e competitividade da agroindústria processadora do grão. Neste contexto, foram calculados o Market Share, a Relação de Concentração e do Índice de Herfindahl-Hirschmann. Confirmou-se a hipótese de que o mercado que fornece insumos para os produtores rurais de soja está altamente concentrado. A hipótese de elevada concentração no segmento de aquisição e processamento da soja também foi confirmada.  Concluiu-se que o produtor rural de soja encontra-se em situação de fragilidade econômica, pois: a adquire insumos em mercado oligopolizado e vende a produção em mercado oligopsonizado; b as empresas dominantes estão protegidas por barreiras à entrada. Diante deste cenário e das análises realizadas, cabe ao Estado brasileiro definir a forma de inserção dos agentes nacionais, em especial do produtor rural: se será caracterizado como um instrumento de acumulação do capital internacional ou se participará dos ganhos e se constituirá como agente de desenvolvimento regional. 

Cultura alfabética y mercado cultural en Colombia y en España

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Ancízar Narváez

2010-01-01

Full Text Available En el presente artículo se establece una comparación entre la oferta y la demanda de cultura alfabética a través de la descripción de los sistemas educativos; así mismo, se compararan la oferta y el consumo mediáticos a través de la descripción de los sistemas mediáticos de Colombia y España. Con estos insumos, se intenta establecer las características del mercado cultural en cada uno de los dos países y sus posibilidades de inserción en el mercado global del conocimiento.

Competencia entre México y China en el interior del mercado de Estados Unidos

OpenAIRE

Gracia-Hernández, Maximiliano

2013-01-01

En este artículo se muestra la dinámica que han seguido las exportaciones de México y China en el interior del mercado de Estados Unidos (EU), se considera la cadena hilo-textil-confección a cuatro dígitos, y se analizan los capítulos 61, 62 y 63. En el año 2000 México era un líder en todas las ramas que componen los capítulos 61 a 63, actualmente sólo cinco de las 30 ramas analizadas han logrado incrementar sus exportaciones en el mercado de EU. Consideramos una verdad a medias que el total ...

Cachorros e humanos: Mercado de rações pet em perspectiva sociológica

OpenAIRE

Mazon, Marcia da Silva; Moura, Wandgleisom Garcia de

2017-01-01

Resumo: O artigo discute mudanças no mercado de rações para animais de estimação a partir do referencial da Sociologia Econômica. Os dados empíricos utilizados são provenientes de entrevistas realizadas com veterinários e donos de pet shops, todas realizadas em Florianópolis, estado de Santa Catarina. Ao longo do artigo abordamos o processo de globalização e suas consequências no mercado de rações. O movimento de fusões e aquisições de empresas multinacionais do setor de rações pet na década ...

Porfiroblastic hornblendites: lithological, guide of arch root plutonism in Piedra Alta Terrane. (Paleoproterozoic, Uruguay)

International Nuclear Information System (INIS)

Bossi, J.; Pineyro, D.

2004-01-01

Petrographic and geochemical features of porphyroblastic hornblendites in Piedra Alta Terrene of Uruguay are described. Their spatial and genetic relationships whith hornblendic gabbros and other basic plutonic rocks is also stablished. Their association with low grade metamorphic supracrustals inmagmatic mingling structures and late development, suggests an origin related to high vapour pressure that take off stability to gabbro paragenesis and favours Deer's reaction:pyroxene+ plagioclase +water= hornblende + SIO2. The silica produced is expressed as quartz dikes frequently mineralized with gold and platinum group elements. San Carlos gabbro is an uruguayan exemple of such proposed model.

ESTRATÉGIAS DE MARKETING INTERNACIONAL E A RELAÇÃO COM A PERFORMANCE EXPORTADORA E ORIENTAÇÃO PARA MERCADO EXTERNO

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Marlon Dalmoro

2009-07-01

Full Text Available O presente trabalho tem como objetivo identificar a relação entre estratégias de marketing das empresas exportadoras do Vale do Taquari, performance exportadora e orientação para mercado externo. Para concretizar o objetivo proposto buscou-se a elaboração de referencial teórico, formado pelos itens estratégias de marketing internacional, performance exportadora e orientação para mercado externo. No nível epistemológico, foi realizado um levantamento tipo survey, com aplicação de questionário em uma amostra de 25 empresas exportadoras que desempenham atividades industriais, escolhidas de maneira não probabilística. Por fim, observou-se que as decisões chaves no modo de atuar nos diversos mercados em termos de estratégias de marketing internacional – satisfação com mercado interno, coerência internacional, adaptação e nível de localização das estratégias – possuem correlação com a orientação para mercado externo e a performance exportadora das empresas estudadas.

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

Science.gov (United States)

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

2014-12-01

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

Paleozoic subduction complex and Paleozoic-Mesozoic island-arc volcano-plutonic assemblages in the northern Sierra terrane

Science.gov (United States)

Hanson, Richard E.; Girty, Gary H.; Harwood, David S.; Schweickert, Richard A.

2000-01-01

This field trip provides an overview of the stratigraphic and structural evolution of the northern Sierra terrane, which forms a significant part of the wall rocks on the western side of the later Mesozoic Sierra Nevada batholith in California. The terrane consists of a pre-Late Devonian subduction complex (Shoo Fly Complex) overlain by submarine arc-related deposits that record the evolution of three separate island-arc systems in the Late Sevonian-Early Mississippian, Permian, and Late Triassic-Jurassic. The two Paleozoic are packages and the underlying Shoo Fly Complex have an important bearing on plate-tectonic processes affecting the convergent margin outboard of the Paleozoic Cordilleran miogeocline, although their original paleogeographic relations to North America are controversial. The third arc package represents an overlap assemblage that ties the terrane to North America by the Late Triassic and helps constrain the nature and timing of Mesozoic orogenesis. Several of the field-trip stops examine the record of pre-Late Devonian subduction contained in the Shoo Fly Complex, as well as the paleovolcanology of the overlying Devonian to Jurassic arc rocks. Excellent glaciated exposures provide the opportunity to study a cross section through a tilted Devonian volcano-plutonic association. Additional stops focus on plutonic rocks emplaced during the Middle Jurassic arc magmatism in the terrane, and during the main pulse of Cretaceous magmatism in the Sierra Nevada batholith to the east.

Mercados de trabajo secundarios e inmigración: el servicio doméstico en Estados Unidos

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Marina Ariza

2011-01-01

Full Text Available El servicio doméstico figura entre los mercados de trabajo secundarios que han cobrado vigencia en el contexto de la globalización. Su dinamismo se relaciona con la demanda de fuerza de trabajo femenina barata para satisfacer necesidades de atención en la esfera de la reproducción doméstica. La caracterización del mercado de trabajo del servicio doméstico en Estados Unidos a principios del siglo XXI con base en datos de encuesta muestra que -ahora como antaño- su crecimiento descansa principalmente en la afluencia de fuerza de trabajo inmigrante, que en nuestros días es principalmente latinoamericana. El nivel de pobreza que acusan y su baja escolaridad, corroboran que el crecimiento de este mercado de trabajo en las sociedades desarrolladas es una más de las secuelas regresivas del mundo del trabajo en el contexto de la globalización.

¿ES DESEABLE LA FUNCIÓN ASIGNATIVA DEL MERCADO DE ALIMENTOS EN UNA ECONOMÍA GLOBAL?

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León Rodríguez Nohra

2008-07-01

Full Text Available El presente documento plantea el problema de la creciente injerencia del libre mercado en la determinación de productos, cantidades y precios de los bienes agropecuarios en la economía global, cuestionando la eficiencia asignativa del mercado, a la vez que pretende advertir sobre algunos riesgos que pueden derivarse del exceso de confianza en el libre mercado, tanto para el bienestar del consumidor, como para la seguridad y soberanía alimentaria de la población, además de los efectos perversos para el medio ambiente y el desarrollo sostenible. Como elemento central, a lo largo del texto, se muestra el papel de las transnacionales agroalimentarias como agentes determinantes en la conducción de la producción, oferta y comercialización de productos, guiadas por el incentivo de la maximización de sus ganancias, mientras las funciones de nutrición, cultura alimentaria y de producción pasan a un segundo plano.

Late magmatic controls on the origin of schorlitic and foititic tourmalines from late-Variscan peraluminous granites of the Arbus pluton (SW Sardinia, Italy): Crystal-chemical study and petrological constraints

Science.gov (United States)

Bosi, Ferdinando; Naitza, Stefano; Skogby, Henrik; Secchi, Francesco; Conte, Aida M.; Cuccuru, Stefano; Hålenius, Ulf; De La Rosa, Nathaly; Kristiansson, Per; Charlotta Nilsson, E. J.; Ros, Linus; Andreozzi, Giovanni B.

2018-05-01

Tourmalines from the late-Variscan Arbus pluton (SW Sardinia) and its metamorphic aureole were structurally and chemically characterized by single-crystal X-ray diffraction, electron and nuclear microprobe analysis, Mössbauer, infrared and optical absorption spectroscopy, to elucidate their origin and relationships with the magmatic evolution during the pluton cooling stages. The Arbus pluton represents a peculiar shallow magmatic system, characterized by sekaninaite (Fe-cordierite)-bearing peraluminous granitoids, linked via AFC processes to gabbroic mantle-derived magmas. The Fe2+-Al-dominant tourmalines occur in: a) pegmatitic layers and pods, as prismatic crystals; b) greisenized rocks and spotted granophyric dikes, as clots or nests of fine-grained crystals in small miaroles locally forming orbicules; c) pegmatitic veins and pods close to the contacts within the metamorphic aureole. Structural formulae indicate that tourmaline in pegmatitic layers is schorl, whereas in greisenized rocks it ranges from schorl to fluor-schorl. Tourmalines in thermometamorphosed contact aureole are schorl, foitite and Mg-rich oxy-schorl. The main substitution is Na + Fe2+ ↔ □ + Al, which relates schorl to foitite. The homovalent substitution (OH) ↔ F at the O1 crystallographic site relates schorl to fluor-schorl, while the heterovalent substitution Fe2+ + (OH, F) ↔ Al + O relates schorl/fluor-schorl to oxy-schorl. Tourmaline crystallization in the Arbus pluton was promoted by volatile (B, F and H2O) enrichment, low oxygen fugacity and Fe2+ activity. The mineralogical evolutive trend is driven by decreasing temperature, as follows: sekaninaite + quartz → schorl + quartz → fluor-schorl + quartz → foitite + quartz. The schorl → foitite evolution represents a distinct trend towards (Al + □) increase and unit-cell volume decrease. These trends are typical of granitic magmas and consistent with Li-poor granitic melts, as supported by the absence of elbaite and other

La adopción de la orientación al mercado en la PYME manufacturera de México

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Gonzalo Maldonado Guzman

2013-12-01

Full Text Available El éxito de las organizaciones, está determinado, en parte, por la demanda de sus bienes y servicios en un mercado altamente globalizado y con un elevado nivel de competitividad, lo cual obliga a las empresas a poner en práctica método y estrategias que permitan mejorar la calidad de sus productos para atraer a un número mayor de clientes. Uno de los métodos más utilizados por las empresas es la orientación al mercado, la cual permite a la organización orientar sus estrategias en la satisfacción de las necesidades y gustos de los clientes. Por lo tanto, en este estudio a partir de una muestra de 285 Pymes manufactureras de Aguascalientes, se analiza la adopción del concepto de orientación al mercado en las Pymes. Los resultados obtenidos muestran que existe una fuerte adopción de los componentes de la orientación al mercado (orientación al cliente, la orientación a la competencia y coordinación interfuncional.

Estrutura do mercado de trabalho metropolitano na Região Sul do Brasil, em 1995 e em 2005

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Armando Vaz Sampaio

2012-07-01

Full Text Available Para melhor compreender as transições que ocorrem no mercado de trabalho, é importante considerar os fluxos de estar empregado, desempregado e fora do mercado de trabalho e as probabilidades envolvidas em função de variáveis socioeconômicas e geográficas. O modelo econométrico utilizado foi o multinomial logit, em que se observou que há diferença de gênero com respeito a estar ocupado e fora do mercado de trabalho, sendo que, para a primeira situação, a probabilidade é maior para o homem e, para a segunda situação, é menor. Verificou-se ainda relação positiva e decrescente entre idade e probabilidade de estar ocupado e relação negativa e decrescente entre idade e possibilidade de estar fora do mercado de trabalho. No que diz respeito à escolaridade, foi encontrada relação positiva sobre a probabilidade de estar ocupado. Ao comparar os anos de 1995 e 2005, verifica-se que a chance de estar desempregado foi maior em 2005.

El higo y sus posibilidades de mercado

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Sonia Barboza Flores

2008-04-01

Full Text Available Este proyecto tuvo como objetivo general “promover la diversificación agrícola del país mediante la generación de tecnologías para la producción e industrialización del cultivo del higo (Ficus carica, así como el establecimiento de nuevas alternativas de mercados y comercialización del producto, con el fin de mejorar las condiciones de vida de los productores”. Como parte de este se procuró el cumplimiento de objetivos específicos como el de “contar con información sobre el estado de la oferta y de la demanda de higo en el país, así como el comportamiento de los precios y de los canales de comercialización existentes” y, también, “ recopilar información sobre la opinión de los consumidores con respecto a las características sensoriales de los productos elaborados a base de higo por el Centro de Investigación en Gestión Agroindustrial, así como medir la eventual intención de compra”.Para estos efectos, se evaluaron distintos factores relacionados con la producción nacional y el uso actual del fruto en su estado fresco y procesado. Además, tomando como base el desarrollo de dos nuevos productos procesados, se hace una evaluación de estos para determinar la aceptación del producto en un mercado regional y para determinar los posibles ajustes que deban hacerse en la formulación del producto.

Estrategias competitivas para los productores cafetaleros de la región de Córdoba, Veracruz, frente al mercado mundial

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Joaquín Perea Quezada

2008-01-01

Full Text Available Este trabajo tiene como objetivo identifi car las estrategias competitivas para los productores cafetaleros de la región de Córdoba, Veracruz. Esto les permitirá competir en un mercado mundial globalizado, el cual se caracteriza por la sobreproducción de café en países como Brasil, Vietnam y Colombia, la fuerte competencia en el mercado de materias primas, el control del grano por un número limitado de países torrefactores y el descenso sostenido de los precios del café oro en el mercado mundial. Estas condiciones complicaron la atención de los cultivos para algunos productores y el abandono total de sus plantaciones para otros, como resultado del descenso de los precios internacionales. El descuido de la producción nacional y la pérdida de espacios han sido aprovechados por los países que vieron la crisis como una oportunidad para extender sus mercados sobre sus competidores más débiles.

Petrography and geochemistry of granitoids from the Samphire Pluton, South Australia: Implications for uranium mineralisation in overlying sediments

Science.gov (United States)

Domnick, Urs; Cook, Nigel J.; Bluck, Russel; Brown, Callan; Ciobanu, Cristiana L.

2018-02-01

The Blackbush uranium deposit (JORC Inferred Resource: 12,580 tonnes U), located on the north-eastern Eyre Peninsula, is currently the only sediment-hosted U deposit investigated in detail in the Gawler Craton. Uranium is hosted within Eocene sandstone of the Kanaka Beds, overlying Mesoproterozoic granites of the Samphire pluton, affiliated with the Hiltaba Intrusive Suite ( 1.6 Ga). These are considered the most probable source rocks for uranium mineralisation. By constraining the petrography and mineralogy of the granites, insights into the post-emplacement evolution can be gained, which may provide an exploration indicator for other sediment-hosted uranium systems. Three geochemically distinct granite types were identified in the Samphire Pluton and correspond to domains interpreted from geophysical data. All granites show complex alteration overprints and textures with increasing intensity closer to the deposit, as well as crosscutting veining. Alkali feldspar has been replaced by porous K-feldspar and albite, and plagioclase is overprinted by an assemblage of porous albite + sericite ± calc-silicates (prehnite, pumpellyite and epidote). This style of feldspar alteration is regionally widespread and known from Hiltaba-aged granites associated with iron-oxide copper-gold mineralisation at Olympic Dam and in the Moonta-Wallaroo region. In two granite types biotite is replaced by calcic garnet. Calc-silicates are indicative of Ca-metasomatism, sourced from the anorthite component of altered plagioclase. Minor clay alteration of feldspars is present in all samples. Mineral assemblages in veins include quartz + hematite, hematite + coffinite, fluorite + quartz, and clay minerals. Minor chlorite and sericite are found in all vein types. All granite types are anomalously rich in U (concentrations between 10 and 81 ppm). Highly variable Th/U ratios, as well as hydrothermal U minerals (mostly coffinite) in granites and veins, are clear evidence for U mobility. Uranium

Parasitosis intestinales en niños ingresados en el Hospital Universitario Pediátrico del Cerro, La Habana, Cuba

OpenAIRE

Núñez, Fidel A.; González, Odalys M.; Bravo, . José R.; Escobedo, Ángel A.; González, Ida

2003-01-01

Se realizó un estudio sobre parasitismo intestinal en 401 niños ingresados en el Hospital Universitario Pediátrico del Cerro entre los meses de mayo y junio de 1999. Para esta finalidad se tomó una muestra representativa, aleatoria y estratificada por servicios. Por cada niño, se recogieron 3 muestras de heces preservadas en formaldehído, las que se procesaron por 3 métodos parasitológicos. La prevalencia de parasitismo intestinal fue de 15 % en el hospital, y no se encontraron diferencias en...

¿Cómo hacer del mercado de capitales, una alternativa para las Pymes en Colombia?

OpenAIRE

Suescún Sanabria, Joan Manuel

2014-01-01

El mercado de capitales en Colombia se caracteriza por ser uno de los más dinámicos de la región de sur América, generando integración entre los sectores deficitarios y superavitarios de recursos monetarios no solo de Colombia sino de Perú y Chile a través de su programa MILA, no obstante se puede definir como un mercado excluyente con definidas capas del sector empresarial nacional, situación particular para las empresas Pymes del país, por lo cual el Estado ha tratado de ofrecer diferentes ...

U-Pb zircon geochronology and Sm-Nd-Pb isotopic constraint for precambrian plutonic rocks in the northeastern part of Ryeongnam massif, Korea

International Nuclear Information System (INIS)

Chang, Ho-Wan

2003-01-01

The Ryeongnam massif is composed of Precambrian gneisses, Paleozoic and Mesozoic sedimentary rocks and extensive Triassic-Jurassic plutonic rocks of felsic to mafic composition. In the northeast Ryeongnam massif, the oldest rocks belong to the Sobaegsan gneiss complex, which is composed of orthogneisses, paragneisses and mafic plutonic rocks. U-Pb zircon ages for the felsic and mafic intrusive bodies within the Sobaegsan gneiss complex are: the Icheon granite gneiss, 2357±43 and 2342±47 Ma; the Buncheon granite gneiss, 1963±5 Ma; the Pyeonghae granite gneiss, 1936±21 Ma; the Ogbang amphibolite, 1918±10 Ma; the Imwon leucogranite gneiss, 1826±20 Ma. The Hyeondong biotite schist, which is intruded by the Buncheon granite gneiss and the Ogbang amphibolite, yielded an age of 2271±44 Ma. The Nd-Sm-Pb isotopic data indicate that the felsic plutonic rocks are derived from an older Archean crust. The Nd T DM ages are Archean, and the εNd values are negative for the felsic rocks and positive for the amphibolite. Common Pb isotope compositions also indicate a crustal source for the felsic intrusives. The U-Pb ages of Precambrian rocks of the Ryeongnam massifs are similar to those in the Gyeonggi massif, and may have a similar crustal evolutionary history. The Precambrian rocks of South Korea could be related either to the North China block or to the South China block, as the isotope ages and patterns are not unique to either block. Similarly, a geologic correlation with Japan, although possible, is tenuous at present. (author)

Caracterización del mercado de arrendamientos urbano para el segmento de la población de bajos ingresos

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Jorge Enrique Torres Ramírez

2008-01-01

Full Text Available Siguiendo los preceptos de la economía urbana, la mayor parte de las necesidades habitacionales se atiende con los servicios derivados de los inmuebles que integran el stock conformado históricamente, representando la oferta y demanda de edificaciones nuevas una proporción mínima del mercado total. Así, los mercados de unidades usadas y, especialmente, los arrendamientos, constituyen segmentos que concentran un volumen de transacciones cuya dimensión, en términos físicos y económicos, representa el mayor componente del mercado total de edificaciones. Los resultados de esta investigación permiten hacer un reconocimiento al aporte del mercado de arrendamientos sobre los niveles actuales de calidad habitacional y de vida en Colombia. Puede plantearse así que sin esta oferta, generada por los hogares de manera directa y en gran parte por formas de producción social, el stock habitacional estaría aún más rezagado respecto de las necesidades habitacionales actuales de los hogares colombianos. En Colombia, el mercado de arrendamientos correspondiente a los hogares de menores ingresos ofrece también un potencial de desarrollo atractivo para los empresarios del sector de la edificación urbana y de la intermediación inmobiliaria. El stock debe crecer más rápido y esta forma de tenencia tiene posibilidades concretas de alojar una importante oferta formal actualmente inexistente.

Notas sobre la ecología de Phyllodactylus reissi (Phyllodactylidae: Sauria) en el Parque Nacional Cerros de Amotape (Tumbes, Perú)

OpenAIRE

Jordán Arizmendi, Juan Carlos

2012-01-01

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 bod...

Casas comerciales y boticas. Aproximación al desarrollo del mercado médico en el Chile urbano, 1860-1910

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María José Correa Gómez

2015-03-01

Full Text Available Este artículo introduce al mercado médico del Chile urbano de fines del XIX e inicios del siglo XX. Reflexiona en torno a las relaciones entre medicalización y comercio, para luego presentar algunas características del mercado médico urbano por medio del comercio exterior, del comercio al por menor y de la celebración industrial. Analiza la expansión del mercado médico y la diversificación de los productos terapéuticos, vinculándolos con los procesos de medicalización y de urbanización de la sociedad chilena.

El mercado transfronterizo de servicios de salud privados entre Tijuana, México y San Diego, EE. UU.

OpenAIRE

Vargas-Hernández, José G.

2005-01-01

En este trabajo se analiza el impacto del comercio transfronterizo en los servicios de salud de Tijuana en el mercado hispano – mexicano e inclusive de otros hispanos latinoamericanos de California. Los hispanos – estadounidenses son de origen mexicano cuyas ligas culturales y familiares los mantienen regresando periódicamente a los pueblos mexicanos de donde son originarios. Los hispanos de California constituyen un mercado que se disputan las compañías aseguradoras. El turismo de hispanos q...

ORGANIZACIÓN Y LOGÍSTICA DEL MERCADO FRESERO ONUBENSE

Directory of Open Access Journals (Sweden)

Juan A. Márquez Domínguez

2001-01-01

Full Text Available La plena integración de España en la Unión Europea, ha expandido y afianzado patrones de consumo interesados por fresas, frambuesas, arándanos y naranjas que constituyen, en una era de la dieta saludable, “la compra impulsiva de todo consumidor” (Kemp, D., 1995... y también el gran negocio de la agricultura de vanguardia, alrededor del cual se agrupan multitud de agentes comerciales con estrategias y visiones de mercado diferentes. Desde hace dos décadas, la Tierra Llana de Huelva, el sector más meridional de la provincia, se está convirtiendo en el espacio indiscutible de la fresa española y europea, siendo la segunda zona productora del mundo, tras California, por obvias ventajas comparativas de índole natural y humana. Sin embargo, el reducido potencial de consumo, por volumen demográfico de los centros de producción de fresas, hace imprescindible contar con mercados externos, alejados cientos y miles de kilómetros. En este contexto, la logística y organización comercial adquiere un papel relevante en la viabilidad de las explotaciones agrarias, ya que de ellas dependen, en gran medida, la rentabilidad económica.

Agricultura brasileira no Mercosul e no mercado internacional

OpenAIRE

Gonçalves, José Sidnei; Instituto de Economia Agrícola

2011-01-01

O mercado internacional vem passando por profundas mudanças no período recente, mudanças que trazem preocupações efetivas para as economias latino-americanas, em especial as do Hemisfério Sul, pois nesse cenário é mais provável que os países industrializados construam uma nova ordem mundial com base nas potências industriais do Hemisfério Norte: Estados Unidos da América (EUA), União Européia (EU) e Japão.

Solvencia y competencia económica en el mercado de seguros de salud español

OpenAIRE

González Gómez, Faustino

2013-01-01

El principal objetivo de este trabajo de investigación es establecer cuáles son los efectos del cambio regulador de solvencia sobre el mercado nacional de seguros de enfermedad o salud conforme a los principios generales definidos por la Directiva de Solvencia II. Se analizan los efectos sobre la protección de los asegurados, la concentración del mercado y la competencia económica. Para la elaboración de este trabajo de investigación se han considerado los principios generales enunciados por ...

Factores clave de gestión económica estratégica del emprendimiento tipo Pyme, vinculados al mercado en Venezuela

OpenAIRE

Alizo, María Alexandra; Escalona, Miriam

2012-01-01

El objetivo de esta investigación fue determinar los factores clave o estratégicos vinculados al mercado para los emprendimientos tipo Pyme en Venezuela. Se utilizó metodología de campo, descriptiva y explicativa, fundamentada en el instrumento de recolección de información Gesecon-EEN y el método estructural prospectivo. Los resultados expresaron los factores clave genéricos de gestión económica del mercado para las Pymes en el país. En el corto plazo: destinar la producción a mercados extra...