New constraints on sediment-flux–dependent river incision: Implications for extracting tectonic signals from river profiles

Abstract

Research Article| July 01, 2008 New constraints on sediment-flux–dependent river incision: Implications for extracting tectonic signals from river profiles Patience A. Cowie; Patience A. Cowie * 1School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK * E-mail: [e-mail]. Search for other works by this author on: GSW Google Scholar Alexander C. Whittaker; Alexander C. Whittaker 1School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK Search for other works by this author on: GSW Google Scholar Mikaël Attal; Mikaël Attal 1School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK Search for other works by this author on: GSW Google Scholar Gerald Roberts; Gerald Roberts 2Joint Research School for Geological and Geophysical Sciences, University College London–Birkbeck College, London WC1E 6BT, UK Search for other works by this author on: GSW Google Scholar Greg E. Tucker; Greg E. Tucker 3Cooperative Institute for Research in Environmental Sciences (CIRES) and Department of Geological Sciences, University of Colorado, Boulder, Colorado 80309, USA Search for other works by this author on: GSW Google Scholar Athanassios Ganas Athanassios Ganas 4Geodynamics Institute, National Observatory of Athens, Thission, Athens 11810, Greece Search for other works by this author on: GSW Google Scholar Geology (2008) 36 (7): 535–538. https://doi.org/10.1130/G24681A.1 Article history received: 20 Dec 2007 rev-recd: 13 Mar 2008 accepted: 22 Mar 2008 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Patience A. Cowie, Alexander C. Whittaker, Mikaël Attal, Gerald Roberts, Greg E. Tucker, Athanassios Ganas; New constraints on sediment-flux–dependent river incision: Implications for extracting tectonic signals from river profiles. Geology 2008;; 36 (7): 535–538. doi: https://doi.org/10.1130/G24681A.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 We present new field data from rivers draining across active normal faults that incise across the same lithology at the fault, have been subjected to similar climatic regimes and tectonic settings, and were perturbed by a well-documented increase in fault slip rate ca. 1 Ma. In spite of these similarities, the rivers exhibit markedly different long profiles and patterns of catchment incision. We use channel slope and hydraulic geometry data for each river to calculate bed shear stresses (τb), and show that there is no simple relationship between peak τb and the relative uplift rates across the faults, U, which differ by a factor of four. The long-term average sediment supply to each channel (Qs), estimated from time-averaged catchment erosion rates, can explain the τb versus U data if bedload modulates bedrock incision rate, E, in a strongly nonlinear way. Together these field data allow us, for the first time, to evaluate theoretical predictions of the role of sediment on river profile evolution and to quantify the magnitude of the effect in natural systems. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.