DOI: 10.1126/science.1148615, 1304 (2008);320 Science, et al.Carmala N. GarzioneRise of the Andes This copy is for your personal, non-commercial use only. clicking here.colleagues, clients, or customers by , you can order high-quality copies for yourIf you wish to distribute this article to others here.following the guidelines can be obtained byPermission to republish or repurpose articles or portions of articles ): September 23, 2011 www.sciencemag.org (this infomation is current as ofThe following resources related to this article are available online at http://www.sciencemag.org/content/321/5894/1295.2.full.htmlA correction has been published for this article at: http://www.sciencemag.org/content/320/5881/1304.full.htmlversion of this article at: including high-resolution figures, can be found in the onlineUpdated information and services, http://www.sciencemag.org/content/suppl/2008/06/05/320.5881.1304.DC1.html can be found at: Supporting Online Material http://www.sciencemag.org/content/320/5881/1304.full.html#relatedfound at:can berelated to this article A list of selected additional articles on the Science Web sites 37 article(s) on the ISI Web of Sciencecited by This article has been http://www.sciencemag.org/content/320/5881/1304.full.html#related-urls21 articles hosted by HighWire Press; see:cited by This article has been http://www.sciencemag.org/cgi/collection/geochem_physGeochemistry, Geophysicssubject collections:This article appears in the following registered trademark of AAAS. is aScience2008 by the American Association for the Advancement of Science; all rights reserved. The title CopyrightAmerican Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. (print ISSN 0036-8075; online ISSN 1095-9203) is published weekly, except the last week in December, by theScience on September 23, 2011www.sciencemag.orgDownloaded fromRise of the AndesCarmala N. Garzione,1* Gregory D. Hoke,1Julie C. Libarkin,2Saunia Withers,3Bruce MacFadden,4John Eiler,5Prosenjit Ghosh,6Andreas Mulch7The surface uplift of mountain belts is generally assumed to reflect progressive shortening andcrustal thickening, leading to their gradual rise. Recent studies of the Andes indicate that theirelevation 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 ofmountain belts probably reflects the rapid removal of unstable, dense lower lithosphere afterlong-term thickening of the crust and lithospheric mantle.The surface uplift of mountain belts, such asthe central Andes plateau, has long beenthought to be the isostatic response ofshortening and thickening of the continental crust.Recently developed isotopic techniques allow usto determine the upl ift history of the central A ndesindependently from the shortening history . Theseresults show that shortening and uplift aretemporally decoupled, with shortening and thick-ening happening over protracted periods of time,whereas uplift occurs geologically rapidly. Thusarises a paradox: Why does slow , continuousshortening and thickening not produce slow,continuous isostatic uplift in the central Andes?Both crustal thickening and the removal ofrelatively dense mantle or lower crust can generateisostatic surface uplif t (1, 2). Paleoelevation studieshelp resolve the geod ynamic evolution of mountainbelts because the rate and lateral extent of surfaceuplift depends on the processes involved. Here, wesynthesize the elevation history of the ce ntralAndes, Earth’s sec o n d l a r g est mountain belt. W ethen compare paleoelevation estimates to histor-ies of regional incision, sedimentation, shorten-ing, and volcanism within the mountain belt tocharacterize lithospheric evolution and the geo-dynamic mechanisms that led to surface uplift.The central Andean plateau (Fig. 1), with awidth of ~400 km and an average elevation of~4 km, is a typical example of an active platemargin where oceanic lithosphere is subducted be-neath continental lithosphere. At its widest, thecentral Andean plateau consists of the internallydrained Altiplano basin at an elevation of ~3800 mthat is bounded by the Western and Eastern Cor-dilleras, where peak elevations exceed 6 km. TheWestern Cordillera is a chain of volcanic edificesassociated with the modern Andean magmatic arc,whereas the Eastern Cordillera and Altiplano basinrecord a history of folding and faulting. The centralAndes have a protracted crustal shortening historyspanning the last 50 million years (My) (3–5)thathas generated crustal thicknesses of ~70 km belowthe highest topography in the Eastern and W esternCordillera and 60 to 65 km below the centralAltiplano (6). Geophysical observations suggest thateclogitic lower crust is absent beneath much of theplateau (6). The mantle between 16°S and 20°Sshows the lowest P wave velocities below theAltiplano/Eastern Cordillera transition, suggestingt h a t virt u ally all of the mantle lithosphere has beenREVIEW1Department of Earth and Environmental Sciences, Universityof Rochester, Rochester, NY 14627, USA.2Department ofGeological Sciences, Michigan State University, East Lansing,MI 48824, USA.3Department of Plant Biology, Michigan StateUniversity, East Lansing, MI 48824, USA.4Florida Museum ofNatural History, University of Florida, Gainesville, FL 32611,USA.5Division of Geological and Planetary Sciences, CaliforniaInstitute of Technology, Pasadena, CA 91125, USA.6Center forAtmospheric and Oceanic Science, Indian Institute of Science,Bangalore, 560 012, India.7Institut für Geologie, UniversitätHannover, 30167 Hannover, Germany.*To whom correspondence should be addressed. E-mail:garzione@earth.rochester.eduPotosiPotosiCorqueCorqueCallapaCallapaSallaSallaJakkokotaJakkokotaPotosiPotosi16°S18°S20°S22°S16°W18°S20°S22°SBoliviaChileArgentinaPeru100020003000400050006000Elevation (m)Distance along profile (km)0 100 200 300 400 500 600 700 800 900 1000TopographyAverage modernMin. & max. modernAverage paleosurface10 Ma paleotopographyFossil plant paleoalt.Stable isotope paleoalt.Swath profileE. Cordillera PaleosurfacesE-m. Mio volcanicsAltiplano floorW. slope paleosurfaces E a s t e r n C o r d i l l e r aA l t i p l a n oW e s t e r n C o r d i l l e r a64°W66°W68°W70°W72°W0JakkokotaJakkokotaSallaSallaCallapaCallapaCorqueCorqueFig. 1. Elevations of the Central Andean plateau based on Shuttle Radar
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