TECTONIC ANALYSIS OF NORTHWESTERN SOUTH AMERICA
... Earth Sciences (in review). Acosta J. E., Hernandez, O., Analisis neotectonico al Este de Pasca, Cundinamarca. ...
... Earth Sciences (in review). Acosta J. E., Hernandez, O., Analisis neotectonico al Este de Pasca, Cundinamarca. ...
How do subduction processes contribute to forearc Andean uplift
... The Carnegie and Nazca ridges are the two largest aseismic ridges being subducted beneath South America. The Carnegie Ridge is subducting beneath Ecuador since at least 1.4 Myrs, but the proposed age for the onset of subduction is disputed and ranges from 1 to 15 Myrs (see Michaud et al., 2009, for ...
... The Carnegie and Nazca ridges are the two largest aseismic ridges being subducted beneath South America. The Carnegie Ridge is subducting beneath Ecuador since at least 1.4 Myrs, but the proposed age for the onset of subduction is disputed and ranges from 1 to 15 Myrs (see Michaud et al., 2009, for ...
Upper-mantle S-velocity structure of central and western South
... Pantanal and Paraná basins are much less elongated, with aspect ratios closer to 1. The Paraná basin is a province of 140-120 Ma old flood basalts covering the basement together with up to 5 km pre- and post-volcanism sediments [Piccirillo and Melfi, 1988; Milani and Zalán, 1999]. The Pantanal we ...
... Pantanal and Paraná basins are much less elongated, with aspect ratios closer to 1. The Paraná basin is a province of 140-120 Ma old flood basalts covering the basement together with up to 5 km pre- and post-volcanism sediments [Piccirillo and Melfi, 1988; Milani and Zalán, 1999]. The Pantanal we ...
Omarini, Ricardo H., Massimo Gasparon, Angelo
... (north and south, respectively) hinged at about 20° latitude south and taking place during the CaboLaventana orogeny (Prezzi and Alonso, 2002; Velázquez et al., 2006). The genesis of the Brazilian magma type (bmt) is linked to the geodynamic processes that promoted the opening of the south Atlantic ...
... (north and south, respectively) hinged at about 20° latitude south and taking place during the CaboLaventana orogeny (Prezzi and Alonso, 2002; Velázquez et al., 2006). The genesis of the Brazilian magma type (bmt) is linked to the geodynamic processes that promoted the opening of the south Atlantic ...
Balancing the force budget of plate tectonics along the Nazca/South
... Bertelloni and Richards, 1998] reveal significant temporal variations in plate velocities for the Cenozoic period. These observations are augmented by a growing body of space geodetic data capable of mapping present-day plate velocities with unprecedented accuracy. For example, the Global Positioni ...
... Bertelloni and Richards, 1998] reveal significant temporal variations in plate velocities for the Cenozoic period. These observations are augmented by a growing body of space geodetic data capable of mapping present-day plate velocities with unprecedented accuracy. For example, the Global Positioni ...
Continental Margin Deformation along the Andean Subduction zone
... chosen this time span because (1) it represents well the order of magnitude of typical discrete deformation events affecting active continental margins (which however, superimpose on regional features resulting from firstorder kinematic and rheological parameters that ...
... chosen this time span because (1) it represents well the order of magnitude of typical discrete deformation events affecting active continental margins (which however, superimpose on regional features resulting from firstorder kinematic and rheological parameters that ...
Bounds on the viscosity coefficient of continental lithosphere from
... Husson and Sempere, 2003] may have redistributed crustal material and contributed to the nearly flat surface of the Altiplano. Lower crustal flow, however, cannot explain the simultaneous rise not only of the Altiplano but also of both the Eastern and Western Cordilleras some 300 km apart, for ...
... Husson and Sempere, 2003] may have redistributed crustal material and contributed to the nearly flat surface of the Altiplano. Lower crustal flow, however, cannot explain the simultaneous rise not only of the Altiplano but also of both the Eastern and Western Cordilleras some 300 km apart, for ...
Molnar, P., and C. N. Garzione (2007), Bounds on the viscosity coefficient of continental lithosphere
... Husson and Sempere, 2003] may have redistributed crustal material and contributed to the nearly flat surface of the Altiplano. Lower crustal flow, however, cannot explain the simultaneous rise not only of the Altiplano but also of both the Eastern and Western Cordilleras some 300 km apart, for ...
... Husson and Sempere, 2003] may have redistributed crustal material and contributed to the nearly flat surface of the Altiplano. Lower crustal flow, however, cannot explain the simultaneous rise not only of the Altiplano but also of both the Eastern and Western Cordilleras some 300 km apart, for ...
cyclicity in cordilleran orogenic systems
... range up to ~400 km (refs 12,13,18–21). As these thrust belts consist almost exclusively of upper-crustal rocks that were detached from the lower-crustal basement and transported towards the foreland region22–24, a slab of lower crust and lithosphere equal in length to the total upper-crustal shorte ...
... range up to ~400 km (refs 12,13,18–21). As these thrust belts consist almost exclusively of upper-crustal rocks that were detached from the lower-crustal basement and transported towards the foreland region22–24, a slab of lower crust and lithosphere equal in length to the total upper-crustal shorte ...
Tectonic Assembly of the Northern Andean Block
... 2) The ‘‘Collision-type’’ classification scarcely considered the mechanics of collisions between a continental block and, for example, oceanic plateaus, and/or aseismic oceanic ridges and immature intra-oceanic arc complexes; even today, these mechanics remains incompletely understood. 3) The role, ...
... 2) The ‘‘Collision-type’’ classification scarcely considered the mechanics of collisions between a continental block and, for example, oceanic plateaus, and/or aseismic oceanic ridges and immature intra-oceanic arc complexes; even today, these mechanics remains incompletely understood. 3) The role, ...
Tertiary tectonics of the sub-Andean region of the North Patagonian
... The sub-Andean region of the North Patagonian Andes is located between the north Patagonian foreland and the highest elevations of the Andean Cordillera. Its Tertiary contractional structure, active since the upper Late Oligocene and through the upper Late Miocene, corresponds to the external sector ...
... The sub-Andean region of the North Patagonian Andes is located between the north Patagonian foreland and the highest elevations of the Andean Cordillera. Its Tertiary contractional structure, active since the upper Late Oligocene and through the upper Late Miocene, corresponds to the external sector ...
Cenozoic tectonic evolution in the Central Andes in northern Chile
... to have been continuous since Late Cretaceous until present, recent studies indicate that the tectonic regime affecting the southern Central Andes varied along strike (Charrier et al. 2009). The present article is part of a broader project attempting to determine along strike variations in the tecto ...
... to have been continuous since Late Cretaceous until present, recent studies indicate that the tectonic regime affecting the southern Central Andes varied along strike (Charrier et al. 2009). The present article is part of a broader project attempting to determine along strike variations in the tecto ...
Tectonic Controls on Volcanism in Southern Andes
... straight line from the northern end of the SVZ (Tupungato) to the southern end (Hudson) a) Cumulative volumes of volcanic edifices, normalized to segment length in cubic kilometers per kilometer arc length (red circles and solid line). b) Spatial distribution of volcanic edifices along the arc in re ...
... straight line from the northern end of the SVZ (Tupungato) to the southern end (Hudson) a) Cumulative volumes of volcanic edifices, normalized to segment length in cubic kilometers per kilometer arc length (red circles and solid line). b) Spatial distribution of volcanic edifices along the arc in re ...
ABSTRAeT RESUMEN
... Between the Pliocene and the Present the volcanic belt from 33-34°S, at the northern end of the Southern Volcanic Zone (SVZ) of the Andes, narrowed into a single chain 01 volcanos as the volcanic lront migrated 35 km to the east and the boundary separating the volcanically quiescent zone to the nort ...
... Between the Pliocene and the Present the volcanic belt from 33-34°S, at the northern end of the Southern Volcanic Zone (SVZ) of the Andes, narrowed into a single chain 01 volcanos as the volcanic lront migrated 35 km to the east and the boundary separating the volcanically quiescent zone to the nort ...
Derived From a Flow Model of Subduction
... 1968;Jischke,1975]. As a result, tio of buoyantto viscousforces[ Turner,1973].ZeroGrashof the strengthof this regionis significantlyweakerthan that number(Gr = 0) indicatesthat buoyancyforcesare negliof the continental lithosphere or of the subducting oceanic gible,whileinfinite Gras_h_of nnrnh•r(_f ...
... 1968;Jischke,1975]. As a result, tio of buoyantto viscousforces[ Turner,1973].ZeroGrashof the strengthof this regionis significantlyweakerthan that number(Gr = 0) indicatesthat buoyancyforcesare negliof the continental lithosphere or of the subducting oceanic gible,whileinfinite Gras_h_of nnrnh•r(_f ...
Range fragmentation of the spectacled bear Tremarctos ornatus in
... habitat between 1,000 and 3,000 m (i.e. the ideal altitudinal extent of forested habitat for bears), although in the inter-Andean valleys of Colombia and Ecuador the lower elevations are highly transformed and forest remains only at the upper elevations (>2,000 m). Proportional availability of fores ...
... habitat between 1,000 and 3,000 m (i.e. the ideal altitudinal extent of forested habitat for bears), although in the inter-Andean valleys of Colombia and Ecuador the lower elevations are highly transformed and forest remains only at the upper elevations (>2,000 m). Proportional availability of fores ...
Garzione, C. N., P. Molnar, J. C. Libarkin, and B, MacFadden (2006), Rapid Late Miocene rise
... broadband recordings of P-to-S wave conversions at the Moho (receiver functions) indicate that the topography of the Andean plateau reflects Airy isostatic conditions, with crustal thicknesses in excess of 70 km below the Eastern and Western Cordillera and between 59 and 64 km in the central Altipla ...
... broadband recordings of P-to-S wave conversions at the Moho (receiver functions) indicate that the topography of the Andean plateau reflects Airy isostatic conditions, with crustal thicknesses in excess of 70 km below the Eastern and Western Cordillera and between 59 and 64 km in the central Altipla ...
Composition of the crust and upper-mantle in the central Andes (19
... which precludes magmatic addition and reinforces they hypothesis of crustal shortening to explain the great thickness of the Altiplano crust. Just re®ning this work, Swenson et al. (2000) ®nd a north±south variation in the structure of the Altiplano, with a mean P wave velocity lower and a s in the ...
... which precludes magmatic addition and reinforces they hypothesis of crustal shortening to explain the great thickness of the Altiplano crust. Just re®ning this work, Swenson et al. (2000) ®nd a north±south variation in the structure of the Altiplano, with a mean P wave velocity lower and a s in the ...
Depth-dependent geometry of margin-parallel strike-slip
... geometry of margin-parallel strike-slip faults within oblique subduction zones. Using an elastic half-space model for the south Chile subduction zone, we show that the geometry of a margin-parallel strike-slip fault as the Liquiñe-Ofqui Fault Zone (LOFZ), is vertical near the free surface and curved ...
... geometry of margin-parallel strike-slip faults within oblique subduction zones. Using an elastic half-space model for the south Chile subduction zone, we show that the geometry of a margin-parallel strike-slip fault as the Liquiñe-Ofqui Fault Zone (LOFZ), is vertical near the free surface and curved ...
Feedback between mountain belt growth and plate convergence
... are thought to provide significant driving force, but the relative magnitudes of other driving and resisting forces are less clear, as are the main factors controlling long-term changes in plate motion. The ability to consider past as well as present plate motions provides significant additional con ...
... are thought to provide significant driving force, but the relative magnitudes of other driving and resisting forces are less clear, as are the main factors controlling long-term changes in plate motion. The ability to consider past as well as present plate motions provides significant additional con ...
The tectonic regime along the Andes: Present
... eastern Pacific region, and mainly along the South American continent, shed light to some geological processes associated with subduction in an Andean-type setting. The objective of this work is to show the geologic characteristics, mainly the structure, magmatism and basin evolution of a series of ...
... eastern Pacific region, and mainly along the South American continent, shed light to some geological processes associated with subduction in an Andean-type setting. The objective of this work is to show the geologic characteristics, mainly the structure, magmatism and basin evolution of a series of ...
Stress field and seismotectonics of northern South America
... South America, and shading denotes different studies. Location of Galápagos Island vector (GALA) has been shifted toward east just so we can show it in our study area (original location is at 90.38W, 0.748S). ...
... South America, and shading denotes different studies. Location of Galápagos Island vector (GALA) has been shifted toward east just so we can show it in our study area (original location is at 90.38W, 0.748S). ...
- Wiley Online Library
... Andean mountain building. The present-day crustal shortening in the Andes is clear from the GPS measurements, but the rate (30–40 mm/a) is higher than the geological shortening rate (<15 mm/a), suggesting that much of the present-day crustal shortening may recover during future earthquakes in the su ...
... Andean mountain building. The present-day crustal shortening in the Andes is clear from the GPS measurements, but the rate (30–40 mm/a) is higher than the geological shortening rate (<15 mm/a), suggesting that much of the present-day crustal shortening may recover during future earthquakes in the su ...
Crustal Shortening and Extension in the Central Andes: Insights
... Furthermore, the current GPS data raise the question of whether the High Andes have been collapsing. Geological studies suggest that N-S extension was a predominant feature in the High Andes in the past few Myr [Dalmayrac and Molnar, 1981; Mercier, 1981; Dewey, 1988]. However, the GPS velocity field ...
... Furthermore, the current GPS data raise the question of whether the High Andes have been collapsing. Geological studies suggest that N-S extension was a predominant feature in the High Andes in the past few Myr [Dalmayrac and Molnar, 1981; Mercier, 1981; Dewey, 1988]. However, the GPS velocity field ...
Andes
The Andes is the longest continental mountain range in the world. It is a continual range of highlands along the western coast of South America. This range is about 7,000 km (4,300 mi) long, about 200 to 700 km (120 to 430 mi) wide (widest between 18° south and 20° south latitude), and of an average height of about 4,000 m (13,000 ft). The Andes extend from north to south through seven South American countries: Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina.Along its length, the Andes is split into several ranges, which are separated by intermediate depressions. The Andes is the location of several high plateaux – some of which host major cities, such as Quito, Bogotá, Arequipa, Medellín, Sucre, Mérida and La Paz. The Altiplano plateau is the world's second-highest after the Tibetan plateau. These ranges are in turn grouped into three major divisions based on climate: the Tropical Andes, the Dry Andes, and the Wet Andes.The Andes is the world's highest mountain range outside of Asia. The highest mountain outside Asia, Mount Aconcagua, rises to an elevation of about 6,961 m (22,838 ft) above sea level. The peak of Chimborazo in the Ecuadorean Andes is farther from the Earth's center than any other location on the Earth's surface, due to the equatorial bulge resulting from the Earth's rotation. The world's highest volcanoes are in the Andes, including Ojos del Salado on the Chile-Argentina border which rises to 6,893 m (22,615 ft).