Aspect-dependent variations in regolith creep revealed by meteoric 10Be

Abstract

Research Article| June 01, 2014 Aspect-dependent variations in regolith creep revealed by meteoric 10Be Nicole West; Nicole West 1Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA Search for other works by this author on: GSW Google Scholar Eric Kirby; Eric Kirby 2College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, USA Search for other works by this author on: GSW Google Scholar Paul Bierman; Paul Bierman 3Department of Geology, and Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, Vermont 05405, USA Search for other works by this author on: GSW Google Scholar Brian A. Clarke Brian A. Clarke 1Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Nicole West 1Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA Eric Kirby 2College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, USA Paul Bierman 3Department of Geology, and Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, Vermont 05405, USA Brian A. Clarke 1Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA Publisher: Geological Society of America Received: 05 Dec 2013 Revision Received: 15 Mar 2014 Accepted: 18 Mar 2014 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2014 Geological Society of America Geology (2014) 42 (6): 507–510. https://doi.org/10.1130/G35357.1 Article history Received: 05 Dec 2013 Revision Received: 15 Mar 2014 Accepted: 18 Mar 2014 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Nicole West, Eric Kirby, Paul Bierman, Brian A. Clarke; Aspect-dependent variations in regolith creep revealed by meteoric 10Be. Geology 2014;; 42 (6): 507–510. doi: https://doi.org/10.1130/G35357.1 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 Although variations in insolation and emergent feedbacks among soil moisture, vegetation, and soil cohesion are commonly invoked to explain topographic asymmetry that depends on aspect, few studies have directly quantified the efficiency of regolith transport along hillslopes of opposing aspect. We utilize meteoric 10Be concentrations in regolith (n = 74) to determine mass flux along equatorial-facing and polar-facing hillslopes in three forested upland watersheds in and adjacent to the Susquehanna Shale Hills Critical Zone Observatory in central Pennsylvania (USA). In combination with regolith depth measurements and high-resolution topography, these fluxes allow us to evaluate transport rate laws and the efficiency of regolith creep. Concentrations of meteoric 10Be in regolith along six separate transects imply that regolith flux is similar along all hillslopes, despite differences in topographic gradient and regolith thickness. Comparison of flux with regolith depth and topographic gradient reveals that transport depends on regolith depth, and that regolith creep is twice as efficient along low-gradient, south-facing slopes with thin regolith as compared to steep, north-facing slopes mantled with thicker regolith. We suggest that the observed topographic asymmetry in these watersheds has evolved over geologic time as a result of differences in the frequency of freeze-thaw events between hillslopes of opposing aspect. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.