Download or read book Quaternary Landscape Evolution of the Southern Central Andes of Chile Quantified Using Landslide Inventories Be and C1 Cosmogenic Isotopes and U Th He Thermochronology written by José Luis Antinao Rojas and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Andes Mountains--the largest subduction orogen in the world--are a unique natural laboratory suited to test interactions at different timescales between tectonic and surface processes. However, Andean Landscape Evolution still remains relatively understudied. This lack of knowledge will probably change during the next few years with growing understanding of Andean rates and styles of geomorphic processes. Long term (10 (super 6) a) landscape evolution of the high relief Cordillera Principal, in the Chilean southern Central Andes (SCA), is strongly marked by the previous tectonic history of the orogen. Exhumation rates determined from apatite (U-Th)/He low-temperature thermochronology are on the order of approximately 1 mm a (super -1) since 2-3 Ma. The exhumation history is consistent with a segmented orogenic architecture in this region, with inherited pre-Cenozoic structures and domains that define not only the distribution of tectonic processes but also erosional styles in response to stress and deformation. Late Pliocene acceleration of exhumation from values of 0.3-0.4 mm a (super -1) has probably occurred along with surface uplift of Cordillera Principal, creating a high elevation area still present today that displays the highest Quaternary erosion rates in the SCA. Quaternary sediment production rates from landslide inventories on a long term (10 (super 6) a) basis (0.16 mm a (super -1) ) are similar to transport rates determined at intermediate timescales (0.25-0.5 mm a (super -1) over 10 (super 3) -10 (super 4) a) with the help of terrestrial cosmogenic nuclide (super 36) Cl inventories in stream sediment. The cosmogenic nuclide study confirmed that landslides dominate denudation providing a distinctive isotopic signature to the different grain sizes of the stream sediment. At short (10 a) timescales, total fluvial transport rates, including a modeled bedload component, are similar (0.25 mm a (super -1) ) to long- and intermediate-term production and transport rates. I conclude that during the Quaternary, occurrence of large landslides and increased activity of fluvial processes during glacial stages have removed efficiently mass from Cordillera Principal, in a waxing orogen. However, variability in erosion over long term timescales and the difference with inferred Quaternary exhumation indicates that a macroscale steady state has not been reached.
Download or read book Quaternary Landscape Evolution of the Southern Central Andes of Chile Quantified Using Landslide Inventories Be and C1 Cosmogenic Isotopes and U Th He Thermochronology written by José Luis Antinao Rojas and published by . This book was released on 2008 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geodynamic Processes in the Andes of Central Chile and Argentina written by S.A. Sepúlveda and published by Geological Society of London. This book was released on 2015-04-09 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Publication arises from the UNESCO-sponsored IGCP 586-Y project `The tectonics and geomorphology of the Andes (32°–34°S): interplay between short-term and long-term processes’. It includes state-of-the-art reviews and original articles from a multidisciplinary perspective that investigate the complex interactions of tectonics and surface processes in the subduction-related orogen of the Andes of central Chile and Argentina (c. 27° –39°S). It aims to improve our understanding of tectonic and landscape evolution of the Andean range at different time scales, as well as the mutual relationship between internal and external mechanisms in Cenozoic deformation, mountain building, topographic evolution, basin development and mega-landslides occurrence across the flat slab to normal subduction segments. The geodynamic processes of the Andes of central Chile and Argentina are analysed from a number of subdisciplines of the Earth sciences, including tectonics, petrology, geophysics, geochemistry, structural geology, geomorphology, engineering geology, stratigraphy and sedimentology.
Download or read book Regional Deformation and Dynamic Processes of the Southern Puna Plateau Central Andes written by Renjie Zhou and published by . This book was released on 2015 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tectonics of the Southern Central Andes written by Klaus-Joachim Reutter and published by Springer. This book was released on 1994 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geodynamics of a Cordilleran Orogenic System The Central Andes of Argentina and Northern Chile written by Peter G. DeCelles and published by Geological Society of America. This book was released on 2015-01-01 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This memoir brings together results from a multidisciplinary study of the processes that have formed the highest, widest part of the Andean Cordilleran orogenic belt in northern Argentina and Chile. The region features a tectonically erosive forearc, protracted arc magmatism, a high-elevation hinterland plateau and strongly shortened retroarc thrust belt, and a Paleocene-Recent foreland basin system"--
Download or read book Quantitative Analysis of the Topographic Evolution of the Andes of Northern Chile Using Cosmogenic Nuclides written by Florian Kober and published by . This book was released on 2004 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Textures Structures and Processes of Volcanic Successions written by Beatriz L.L. Coira and published by Springer Nature. This book was released on 2020-09-18 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a complete study of the Central Andean volcanism and its most distinctive features, from the lower Paleozoic to the Cenozoic times in the framework of its processes, eruptive mechanisms and geodynamic conditions. It helps readers understand the nature of the volcanic geology and the volcaniclastic related deposits linked to the evolution of the Andean continental margin. Special attention is paid to the analysis of the ancient volcanic successions and the difficulties in recognition of the original rock type caused by the effects of deformation, metamorphism and alteration. The authors use distinctive cases to describe how to apply different tools in analysis and interpretation. The selected representative, well exposed and preserved volcanic records of the Southern Central Andes analyzed in this book open new perspectives in the understanding of the volcanic processes linked to active continental margins as the Central Andes. This book will be of special interest to volcanologists and specialists in the earth sciences and appeal to both undergraduate and graduate students in geology.
Download or read book Soils and Quaternary Landscape Evolution written by John Boardman and published by . This book was released on 1995 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evolution of the Chilean Argentinean Andes written by Andrés Folguera and published by Springer. This book was released on 2018-04-13 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the Mesozoic to Cenozoic evolution of the Chilean and Argentinean Andes. The book is structured from a historical perspective concentrating on specific processes explained in each chapter. The chapters cover dynamic subsidence; neotectonics; magmatism; long and short term deformation; spatial development of ancient orogenic processes that control Andean reactivations; relation between ocean bathymetry and deformation. Sources of detritus through Andean construction are discussed by specialists from both sides of the Southern Andes. This book provides up-to-date reviews, maps, evolutionary schemes and extensive reference lists useful for geoscientists and students in Earth Science fields.
Download or read book Cenozoic and Quaternary Lacustrine Systems in Northern Chile Central Andes Arc and Fore Arc Zones written by A. Sáez and published by . This book was released on 1996 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pliocene Pleistocene Landscape Evolution in South Central Chile written by Katrin Rehak and published by . This book was released on 2008 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neogene Tectonic and Exhumation of the Andes Centrales Southern Peru written by Carlos Lenin Benavente Escobar and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACTTiming and mechanisms of uplift in the Central Andes have been a matter of debate since at least the 1970's. Our study focuses on Cenozoic deformation and exhumation of the Central Andean forearc in Peru, in Cuzco region, and between the Western Cordillera and the Coastal Cordillera in Nazca region. Our new mapping of active faults provides new insights into the Cenozoic to present-day crustal deformation of the Central Andean Western margin. Until now, apart from some local studies, the geomorphology of the Andean forearc has classically been presented as a remnant Miocene landscape with no significant active structures accommodating the Cenozoic deformation. Thanks to new high-resolution optical imagery, the well-preserved geomorphic surfaces developed within the forearc of southern Peru provide excellent regional markers to map patterns of deformation. Pertaining to the Cenozoic history, while the timing of uplift-related exhumation and Cenozoic exhumation has been studied in Colca and Cotahuasi canyons, it remain poorly constrained in the northern segment of the Central Andean forearc. I report new apatite (U-Th)/He (AHe) and fission track (AFT) ages from the western Cordillera between Cañete and Nazca along two new cross sections. The ages in Nazca region reflect relatively recent (since ~10Ma) relief creation along the western margin of the Altiplano, similar to what is described south in Colca region.The Quaternary tectonic history is revealed by the newly mapped fault segments affecting the Miocene deposits within forearc. Through field and remote mapping, I determined fault geometries and maximum ages for the activity of the faults systems based on stratigraphic relationships in order to assess the role of this tectonic activity in the Western Cordillera uplift and exhumation.To understand the Holocene tectonic history, we use in situ produced 10Be to determine the exposure ages of the free face and tectonic scarp of the Purgatorio Fault in order to map the temporal evolution of its seismotectonic activity. Our new results display evidence of transpression and the formation of meter-high coseismic scarps as well as very recent exposure ages indicating a youthful fault morphology and Mw6-7 earthquakes occurring along the Purgatorio fault segments. These new data are in contrast with some previous conclusions for this region which suggest extension and/or slow rates of deformation for this region and time period. Further, these new data not only suggest significant active deformation within the forearc, but also highlight a potential seismic hazard for the region that not take into account crustal forearc faults.While the general assumption is that active deformation is localized in the Subandean fold and thrust belt, or east of the Western Cordillera in the Altiplano, our data support a model where active deformation is occurring in the western margin as well, along the Incapuquio Fault and other neotectonic faults that accommodates the partitioning of the subduction oblique convergence.These crustal active faults and more precisely the “not migrating to the trench” Incapuquio fault zone reveal the rigid motion of the forearc. Our new model is nevertheless compatible with the recently published GPS data that measure a southeastward movement at 4-5 mm/yr relative to a stable South America reference frame. This rigid motion is in part due to the presence of the rigid Greenvillian accreted craton, that behave as a sliver, and rather tilt than deform through time.
Download or read book Textures Structures and Processes of Volcanic Successions written by Beatriz L.L. Coira and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a complete study of the Central Andean volcanism and its most distinctive features, from the lower Paleozoic to the Cenozoic times in the framework of its processes, eruptive mechanisms and geodynamic conditions. It helps readers understand the nature of the volcanic geology and the volcaniclastic related deposits linked to the evolution of the Andean continental margin. Special attention is paid to the analysis of the ancient volcanic successions and the difficulties in recognition of the original rock type caused by the effects of deformation, metamorphism and alteration. The authors use distinctive cases to describe how to apply different tools in analysis and interpretation. The selected representative, well exposed and preserved volcanic records of the Southern Central Andes analyzed in this book open new perspectives in the understanding of the volcanic processes linked to active continental margins as the Central Andes. This book will be of special interest to volcanologists and specialists in the earth sciences and appeal to both undergraduate and graduate students in geology.
Download or read book Unraveling the Magmatic and Geomorphic Processes Recorded in the Topography of the Central Andes written by and published by . This book was released on 2015 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: The topography of volcanic arcs reflects a combination of magmatic ascent processes that deform the overlying crust, volcanic eruptions that blanket the surface in lava and ash, and geomorphic processes that shape these deposits into the observable landscape and consequently record an erosional archive of surface deformation. A central goal of geomorphology is to utilize the form of landscapes to infer the processes that shape them, yet comparatively little work has been done to quantitatively understand the geomorphology of volcanic landscapes. The Central Volcanic Zone of the South American Andes (CVZ, 15-28°S) represents an ideal location for understanding the processes that shape the surface of volcanic arcs; the arid climate and well-constrained geochronology of volcanic deposits provide a geomorphic archive going back 11 Myrs, and the wealth of available geophysical imaging data provides a high-resolution glimpse into the subsurface. In this thesis I utilize geormophic and geophysical data to explore fundamental questions in volcanic landscape evolution at varying spatial scales. To begin, I examine the isostatic uplift response to crustal intrusion of mantle-derived melt, resulting in growth of the largest known active magma reservoir on Earth (the Altiplano-Puna Magma Body). From topography I show that it is possible to calculate the contribution of mantle-derived melt to crustal thickening, and I compare these results to independent seismic estimates that agree well with our data. I then use the record of volcanic deposits from the Altiplano-Puna Magma Body to estimate the flux of mantle melt into the crust, and show that predicted uplift rates are comparable to the surface uplift associated with convective lithospheric removal. Next, I explore how the topography of individual volcanic systems can help discern the style of melt ascent from deeper crustal magma reservoirs to shallow ones. Using two actively deforming volcanoes in the CVZ, Uturuncu volcano and the Lazufre volcanic complex, I use river profiles, lake shorelines, and lava flow deflections to infer each volcano's surface deformation record into the geomorphic past. Uturuncu volcano shows little signs of permanent paleo-deformation, suggesting transient ascent of magma over millenial timescales, while Lazufre's long wavelength deformation suggests continued accumulation of magma since > 0.3 Ma. Finally, I utilize the unique topography of a windswept ignimbrite erupted from the Altiplano-Puna Magma body to better understand how wind abrasion can incise bedrock canyons, a fundamental geomorphic process in arid landscapes on both Earth and Mars. Using a natural experiment within the 4 Ma Puripicar ignimbrite on the western slope of the Central Andes, we quantify the relative contribution of wind and water erosion in propagating bedrock canyons and show that wind can incise canyons an order of magnitude faster than rivers, streamlining their profiles in the process. Thus, in these chapters I illustrate how geomorphology can be a useful tool for quantifying subsurface magmatic processes, while volcanic landscapes themselves can also provide unique opportunities for understanding fundamental planetary geomorphic processes not often observed elsewhere on Earth.
Download or read book Biodiversity and Conservation of Neotropical Montane Forests written by Steven P. Churchill and published by New York Botanical Garden Press. This book was released on 1995 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mountain plants, Andes Region.
Download or read book Geomorphology written by Robert S. Anderson and published by Cambridge University Press. This book was released on 2010-06-17 with total page 655 pages. Available in PDF, EPUB and Kindle. Book excerpt: A modern, quantitative, process-oriented approach to geomorphology and the role of Earth surface processes in shaping landforms, starting from basic principles.
