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Region Sierras Pampeanas Pdf Region sierras pampeanas pdf Continue doi: 10.2475/ajs.286.10.737 AJS Online December 1986 vol. 286 No 10 737-764 Load with a link to an article with reference to articles via Google Scholar Load related web page information Page 2 doi: 10.2475/ajs.286.10.765 AJS Online December 1986 vol. 286 No. 10 765-791 Show PDF in full window Full Text (PDF) Load with reference to article information Citing articles via Google Scholar Articles Ellis, D. J. Search for imaginary content Load related web page information Around the last 10 million years of the cape subductive sub-horizon form directly under the advanced lithosphere of the province of Sierra Pampenas, in the west of Argentina. During this time, the middle and upper cortex split into many faulty blocks separated by reverse faults. Non-pool pools fill wide valleys between basement lifts. The theory predicts that there may be longwave subsidence throughout the Sierras Pampeanas area due to the flat subduction of the plate beneath it. However, the tectonic province of Sierra Pampean is well above sea level and may have risen topographically since the Mid-Miocene, when the sea splashed around the edges. Various geophysical studies also show that the crust is very thick, thicker than one would expect for the continental crust at its current height. How are these facts related to each other? First, we tested the suggestion that there are sea layers of the Miocene age in the Sierra Pampeans that would be a solid paleotopographic marker. Isotopic studies of PhD student Brian Raskin on possible marine limestone show that they are much more likely to be lacustrique deposits, and thus there is no evidence of sea level rise in Neogene. Working with Mario Jimenez and colleagues from the National University of San Juan (research of the gravitational field and magnetic field) and Fede Devil from the National University of Cordoba (field geology, geochronology, interpretation of seismic reflections and mechanical modeling), aimed at more accurate definition of geometry and history of neogenic sedimentary basins of Sierra Pampean. The geophysical characterization of the deep crust and flat plate lithosphere, conducted by a team of the University of Arizona led by Susan Beck and George Sandt, provided a valuable context for our studies of topographical evolution. The reflection of seismic profiles (provided by RepsolYPF) illustrates that thick clusters of neogene (?) layers are not related to the modern morphology of the basin and range. Fede Devila explored the role of dynamic subsidence associated with the alignment of the Nasca subduction slab under South America in the regional development of the basin. Some of the relevant publications are: Davila, F., Jordan, T.E., and Asty, R., 2005, LongWave in Andes broken through shadow: Near-fused control on sedimentary and topography topography Pampinaas? 6th International Symposium on Andean Geodynamics (ISAG Barcelona), IRD Editions (Institut de Recherche pour le Developpement) Paris, page 211-214.Devila, F.M., Astiny, R.A., Jordan, T.E., 2005, Kargas subcorcatalites en el anthepas yn y la planicie pampeana: evidencias estratigr'ficas, totrogrifikas y geof'sicas: Revista de la Asociaci'n Geol'tica Argentina, v. p.775-786.Fisher, N.D., Jordan, T.E., and Brown, L., 2002, Structural and Stratigraphic Evolution of the La Rioja Basin, Argentina: Journal of South American Earth Sciences, Art 15, p. 141-156. Jordan, T.E., and Allmendinger, R.W., 1986, SierraS Pampeanas of Argentina: The modern analogue of the deformation of the rocky mountains foreland: American Journal of Science, art. 286, p.737-764. Jordan, T.E., Seitler,., Ramos, VA, and Gleadow, A.J.W., 1989, Thermo-chronometric data on the development of the basement foamline in SierraS Pampeanas, Argentina: Journal of South American Earth Sciences, Article 2, #3, page 207-222.Allmendinger, R.W., and Jordan, T.E., 1989 Geological Map of the Newfoundland Mountains, Northwest, Utah (scale 1:31, 680): U.S. Geological Survey, Map MF-2087. Tabbutt, K, Naezer, KV, Jordan, T.E. and Cerveny, P.F., 1989, New fission-track Ages of Mio-Plioocene Tuffs in Sierras Pampeanas and Precordirier Argentina: Asociaci'n Geol'gica Argentina, Revista, 34, p. 408-419Gimenez, M.E., Martinez, M.P., Jordan, T., Ruiz, F., Lins Klinger, F., 2009, Gravity Characteristics of the La Rioja Valley Basin, Argentina: Geophysics, Art 74, No. 3, DOI. 10.1190/1.3103247 This article needs additional quotes to be verified. Please help improve this article by adding quotes to reliable sources. Non-sources of materials can be challenged and removed. Find sources: Sierras Pampeanas - News newspaper book scientist JSTOR (December 2017) (Learn how and when to remove this template message) Location of the Cerro region of General Belgrano west side of Champaqu after the snowfall Of Trithrinax campestris forest near Papagaios Sierras Pampeanas (also called Central Sierras or Pampas Sierra) (English: Pampas Sierra) (English: Pampas Mountain) The Sierra Pampeana is a chain of mountains that rise sharply from the surrounding region of Pampa in northwestern Argentina. They run parallel to the Andes, and their crest line is about 540 km (340 miles) east of the Andean crest line (running from 29 to 35 S latitudes about 65 W longitude). They cross seven provinces of Argentina: San Luis, San Juan, Cordoba, La Rioja, Catamarca, Santiago del Estero and Tucuman. The geography of the highest point of the Sierra Pampean is Cerro General Belgrano (6,250 m above sea level) in La Rioja, in the Area of Famatina. Between the high points are several salt-filled depressions. Depression Salinas Grandes in Cordoba, La Rioja, Catamarque and Santiago del Estero. A characteristic feature of many of these mountain ranges is their morphological asymmetry: the western slopes are usually steeper than the eastern slopes, so the former are sometimes called coasts, and the latter are called skirts. Narrow valleys are called broken or open; narrow openings between valleys are called doors. Due to erosion and other geological forces (volcanoes, glaciers, rivers, tectonics, etc.), the surface of this area varies greatly. It includes rocks and narrow channels of some rivers that are called crates (if they are moderate in size) or cannons (if they are older); There are abundant caves, grottoes and overhangs. Some mountains are separated by large open areas (too large to be considered a valley); they are called barreals (mud flats) or pampas (herbal plains). Geology See also: Achala Batolith and the Pampei Flat Plate Before the Mesozoic Sierra Pampeana were affected by cycles of oregon events produced by a series of continental collisions along the proto-Pacific edge of Gondwana. The neoprotherosoysian Cambrian Pameese orage was a major event along the southwestern Gondwana, which coincided with the end of the Brazilian-Pan-African beard. In Cambrian, subductions along the proto- Pacific edge lead to famatinian orogeny which accretes Precordillera Terrane in Gondwana. In the horn of Gondwanida Gondwana reached its maximum level at the beginning of carbon and began to disintegrate in the early cretaceous. Along the Pacific region, the convergence of tectonic plates leads to the resumption of subduction, leading to large Riolitic provinces and the plutonium belts of the Permian-Jurassic period. By the end of the Paleozoic erosion, a penepley had been forming in the eastern Sierra Pampean. Later tectonic movements divided this surface into different levels, with the highest level being Pampa de Achala. As the South Atlantic opened after the basalt floods of Parana-Etendek, the Andean formation of the Andes, a product of volcanism and compression forces along the Pacific region, but also led to the development of elongating basins in South America and passive reserves along the Atlantic coast, processes continue to this day. The basement of the Sierra Pampean was raised during the Andean oreganoia over the almost horizontal segment of the Subduction Plate of The Attack. The Sierras Pampeanas also suffered from the magmatism of the Miocene arc 700 km east of the Chilean Trench during this period. Climate and hydrography This region has a temperate and semi-arid climate, with warm summers and cool winters. The north eastern slope is covered with tropical forests, due to the high humidity in this subtropical zone. Parts in Cordoba and San Luis enjoy a Mediterranean-style climate, with intense summers and snowy winters; the vegetation here includes coniferous trees. More precipitation falls on the eastern slopes, which are met by wet winds from the Atlantic Ocean. Groundwater is not abundant in most of this area; the eastern slopes show a large population due to the greater water flow available there. There are short, torrential rivers and many streams and rivers that carry low streams, with brief and violent floods caused by summer rains. These rivers are used to produce hydropower. Flora and fauna Flora Extant species include algarrobo Blanco (white carob), algarrobo negro, chanar, jarilla, mystol, piquinine, tala, alpataco, tabaquillo and espinillo. In the more arid regions (western faces) grow giant or medium cacti and various shrubs (chill, tola, etc.) Because more rainfall is available, vegetation is dense with trees such as conifers, alders, deciduous trees including walnut, jacaranda, pisonia, Schinus mollee, que que que. The areas of Cordoba and San Luis have abundant vegetation on the eastern slopes, including carob, coconuts (local name for palm trees), garabato blanco (acacia) and willow. On the hills of Cordoba there are olives, peach, pear, apricot, fig trees, iva, lemon trees, cypress, Cedar, Pine, Eucalyptus, Poplar, Oak and Willow Especially in the areas of Cordoba and San Luis are shrubs and medicinal herbs of peperin, pennyroyal, dandelion, banana, banana, grapes of mounts Fertile Valley in San Juan In arid areas such as the center and west of La Rioja and Catamark, the vines are smeared with , (jujube was delivered by Lebanese immigrants and Syrians in the early twentieth century), grains, aloe and jojoba.
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