Rise of the Andes Carmala N Garzione et al Science 320 1304 2008 DOI 10 1126 science 1148615 This copy is for your personal non commercial use only If you wish to distribute this article to others you can order high quality copies for your colleagues clients or customers by clicking here The following resources related to this article are available online at www sciencemag org this infomation is current as of September 23 2011 A correction has been published for this article at http www sciencemag org content 321 5894 1295 2 full html Updated information and services including high resolution figures can be found in the online version of this article at http www sciencemag org content 320 5881 1304 full html Supporting Online Material can be found at http www sciencemag org content suppl 2008 06 05 320 5881 1304 DC1 html A list of selected additional articles on the Science Web sites related to this article can be found at http www sciencemag org content 320 5881 1304 full html related This article has been cited by 37 article s on the ISI Web of Science This article has been cited by 21 articles hosted by HighWire Press see http www sciencemag org content 320 5881 1304 full html related urls This article appears in the following subject collections Geochemistry Geophysics http www sciencemag org cgi collection geochem phys Science print ISSN 0036 8075 online ISSN 1095 9203 is published weekly except the last week in December by the American Association for the Advancement of Science 1200 New York Avenue NW Washington DC 20005 Copyright 2008 by the American Association for the Advancement of Science all rights reserved The title Science is a registered trademark of AAAS Downloaded from www sciencemag org on September 23 2011 Permission to republish or repurpose articles or portions of articles can be obtained by following the guidelines here CORRECTED 5 SEPTEMBER 2008 SEE LAST PAGE associated with the modern Andean magmatic arc whereas the Eastern Cordillera and Altiplano basin record a history of folding and faulting The central Andes have a protracted crustal shortening history spanning the last 50 million years My 3 5 that has generated crustal thicknesses of 70 km below the highest topography in the Eastern and Western Cordillera and 60 to 65 km below the central Altiplano 6 Geophysical observations suggest that eclogitic lower crust is absent beneath much of the plateau 6 The mantle between 16 S and 20 S shows the lowest P wave velocities below the Altiplano Eastern Cordillera transition suggesting that virtually all of the mantle lithosphere has been Rise of the Andes Carmala N Garzione 1 Gregory D Hoke 1 Julie C Libarkin 2 Saunia Withers 3 Bruce MacFadden 4 John Eiler 5 Prosenjit Ghosh 6 Andreas Mulch7 The surface uplift of mountain belts is generally assumed to reflect progressive shortening and crustal thickening leading to their gradual rise Recent studies of the Andes indicate that their elevation remained relatively stable for long periods tens of millions of years separated by rapid 1 to 4 million years changes of 1 5 kilometers or more Periodic punctuated surface uplift of mountain belts probably reflects the rapid removal of unstable dense lower lithosphere after long term thickening of the crust and lithospheric mantle T 16 S e Peru s te te Jakkokota o rd 18 S ill era Potosi 20 S ra Swath profile Callapa no Stable isotope paleoalt Salla 16 W Bolivia pla Fossil plant paleoalt 64 W rn Corque ille 20 S 66 W C 18 S as ti 1304 E W rd To whom correspondence should be addressed E mail garzione earth rochester edu 68 W Co Department of Earth and Environmental Sciences University of Rochester Rochester NY 14627 USA 2Department of Geological Sciences Michigan State University East Lansing MI 48824 USA 3Department of Plant Biology Michigan State University East Lansing MI 48824 USA 4Florida Museum of Natural History University of Florida Gainesville FL 32611 USA 5Division of Geological and Planetary Sciences California Institute of Technology Pasadena CA 91125 USA 6Center for Atmospheric and Oceanic Science Indian Institute of Science Bangalore 560 012 India 7Institut f r Geologie Universit t Hannover 30167 Hannover Germany 70 W rn 1 72 W Al he surface uplift of mountain belts such as the central Andes plateau has long been thought to be the isostatic response of shortening and thickening of the continental crust Recently developed isotopic techniques allow us to determine the uplift history of the central Andes independently from the shortening history These results show that shortening and uplift are temporally decoupled with shortening and thickening happening over protracted periods of time whereas uplift occurs geologically rapidly Thus arises a paradox Why does slow continuous shortening and thickening not produce slow continuous isostatic uplift in the central Andes Both crustal thickening and the removal of relatively dense mantle or lower crust can generate isostatic surface uplift 1 2 Paleoelevation studies help resolve the geodynamic evolution of mountain belts because the rate and lateral extent of surface uplift depends on the processes involved Here we synthesize the elevation history of the central Andes Earth s second largest mountain belt We then compare paleoelevation estimates to histories of regional incision sedimentation shortening and volcanism within the mountain belt to characterize lithospheric evolution and the geodynamic mechanisms that led to surface uplift The central Andean plateau Fig 1 with a width of 400 km and an average elevation of 4 km is a typical example of an active plate margin where oceanic lithosphere is subducted beneath continental lithosphere At its widest the central Andean plateau consists of the internally drained Altiplano basin at an elevation of 3800 m that is bounded by the Western and Eastern Cordilleras where peak elevations exceed 6 km The Western Cordillera is a chain of volcanic edifices E Cordillera Paleosurfaces E m Mio volcanics 22 S 22 S Altiplano floor W slope paleosurfaces Chile Argentina 6000 Topography Elevation m 5000 Average modern Min max modern Average paleosurface 10 Ma paleotopography 4000 3000 2000 1000 0 0 100 200 300 400 500 600 700 800 900 1000 Distance along profile km Fig 1 Elevations of the Central Andean plateau based on Shuttle Radar Topography Mission 30 data and modern versus 10 Ma paleotopography profiles Top Shaded relief topography of the central Andean plateau between 17 5 S and 23 S
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