Exhumation by debris flows in the 2013 Colorado Front Range storm

Abstract

Research Article| May 01, 2015 Exhumation by debris flows in the 2013 Colorado Front Range storm Scott W. Anderson; Scott W. Anderson 1Department of Geography, and Institute of Arctic and Alpine Research (INSTAAR), University of Colorado, Boulder, Colorado 80309, USA *Current address: U.S. Geological Survey, Tacoma, Washington 98402, USA. Search for other works by this author on: GSW Google Scholar Suzanne P. Anderson; Suzanne P. Anderson † 1Department of Geography, and Institute of Arctic and Alpine Research (INSTAAR), University of Colorado, Boulder, Colorado 80309, USA †E-mail: Suzanne.Anderson@colorado.edu Search for other works by this author on: GSW Google Scholar Robert S. Anderson Robert S. Anderson 2Department of Geological Sciences, and Institute of Arctic and Alpine Research (INSTAAR), University of Colorado, Boulder, Colorado 80309, USA Search for other works by this author on: GSW Google Scholar Geology (2015) 43 (5): 391–394. https://doi.org/10.1130/G36507.1 Article history received: 05 Dec 2014 rev-recd: 03 Feb 2015 accepted: 08 Feb 2015 first online: 09 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 Scott W. Anderson, Suzanne P. Anderson, Robert S. Anderson; Exhumation by debris flows in the 2013 Colorado Front Range storm. Geology 2015;; 43 (5): 391–394. doi: https://doi.org/10.1130/G36507.1 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 The relative importance of extreme events in the long-term exhumation of landscapes is difficult to determine; the degree to which modern records capture long-term mean process rates is therefore commonly unknown. In September 2013, a massive precipitation event in the Front Range of Colorado (USA) triggered over 1100 landslides and debris flows in a historically sedate landscape. Here we employ topographic differencing, utilizing repeat aerial lidar, to quantify net sediment transport volumes in 120 of these mass movements within an area of 102 km2 west of Boulder, Colorado. Comparing our results against published long-term erosion rates, we find that these mass movements evacuated the equivalent of hundreds to thousands of years of hillslope weathering products. We conclude that (1) rare debris flows perform the majority of sediment transport and channel erosion within steep channels along the eastern edge of the Front Range, potentially explaining discrepancies between modern sediment yields and long-term erosion rates in such settings, and (2) the high spatial density of debris flows along the corridors bounding steep canyons suggests that the landscape switches to debris-flow dominance as knickpoints pass headward along the canyons. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.