Climate-driven processes of hillslope weathering

Abstract

Research Article| November 01, 2009 Climate-driven processes of hillslope weathering Jean L. Dixon; Jean L. Dixon * 1School of Earth and Space Exploration, Arizona State University, 548 Physical Sciences F-wing, Tempe, Arizona 85287, USA *E-mails: jean.dixon@asu.edu; arjun.heimsath@asu.edu; jmkaste@wm.edu; earthy@nature.berkeley.edu (Amundson). Search for other works by this author on: GSW Google Scholar Arjun M. Heimsath; Arjun M. Heimsath * 1School of Earth and Space Exploration, Arizona State University, 548 Physical Sciences F-wing, Tempe, Arizona 85287, USA *E-mails: jean.dixon@asu.edu; arjun.heimsath@asu.edu; jmkaste@wm.edu; earthy@nature.berkeley.edu (Amundson). Search for other works by this author on: GSW Google Scholar James Kaste; James Kaste * 2Department of Geology, College of William and Mary, 217 McGlothlin-Street Hall, Williamsburg, Virginia 23187, USA *E-mails: jean.dixon@asu.edu; arjun.heimsath@asu.edu; jmkaste@wm.edu; earthy@nature.berkeley.edu (Amundson). Search for other works by this author on: GSW Google Scholar Ronald Amundson Ronald Amundson * 3Department of Environmental Science, Policy and Management, University of California–Berkeley, 137 Mulford Hall, Berkeley, California 94720, USA *E-mails: jean.dixon@asu.edu; arjun.heimsath@asu.edu; jmkaste@wm.edu; earthy@nature.berkeley.edu (Amundson). Search for other works by this author on: GSW Google Scholar Geology (2009) 37 (11): 975–978. https://doi.org/10.1130/G30045A.1 Article history received: 19 Jan 2009 rev-recd: 09 Jun 2009 accepted: 09 Jun 2009 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Jean L. Dixon, Arjun M. Heimsath, James Kaste, Ronald Amundson; Climate-driven processes of hillslope weathering. Geology 2009;; 37 (11): 975–978. doi: https://doi.org/10.1130/G30045A.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Climate controls erosion and weathering on soil-mantled landscapes through diverse processes that have remained difficult to disentangle due to their complex interactions. We quantify denudation, soil and saprolite weathering, and soil transport near the base and crest of the western slope of the Sierra Nevada to examine how large differences in climate affect these processes. Depth profiles of fallout radionuclides and field observations show relative differences in erosion and weathering processes at these two climatically diverse sites, and our data suggest fundamentally different patterns of soil production and transport mechanisms: biotically driven soil transport at low elevation, and surface erosion driven by overland flow at high elevation. Soil production rates from cosmogenic 10Be decrease from 31.3 to 13.6 m/Ma with increasing soil depth at low elevation, but show uncertain depth dependence at the high elevation site. Our data also show a positive correlation between physical erosion and saprolite weathering at both sites. Highly weathered saprolites are overlain by weakly weathered and rapidly eroding soils, while chemically less depleted saprolites are overlain by slowly eroding, more weathered soils. Our data are among the first to quantify the critical role of saprolite weathering in the evolution of actively eroding upland landscapes, and our results provide quantitative constraints on how different climates can shape hillslopes by driving processes of erosion and weathering. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.