Geometry and grain-size characteristics of the basal surface of a braided river deposit

Abstract

Research Article| March 01, 2011 Geometry and grain-size characteristics of the basal surface of a braided river deposit J. Tobias Gardner; J. Tobias Gardner Department of Geography, University of Western Ontario, London, Ontario N6A 5C2, Canada Search for other works by this author on: GSW Google Scholar Peter E. Ashmore Peter E. Ashmore Department of Geography, University of Western Ontario, London, Ontario N6A 5C2, Canada Search for other works by this author on: GSW Google Scholar Author and Article Information J. Tobias Gardner Department of Geography, University of Western Ontario, London, Ontario N6A 5C2, Canada Peter E. Ashmore Department of Geography, University of Western Ontario, London, Ontario N6A 5C2, Canada Publisher: Geological Society of America Received: 03 Aug 2010 Revision Received: 05 Oct 2010 Accepted: 08 Oct 2010 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2011 Geological Society of America Geology (2011) 39 (3): 247–250. https://doi.org/10.1130/G31639.1 Article history Received: 03 Aug 2010 Revision Received: 05 Oct 2010 Accepted: 08 Oct 2010 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 J. Tobias Gardner, Peter E. Ashmore; Geometry and grain-size characteristics of the basal surface of a braided river deposit. Geology 2011;; 39 (3): 247–250. doi: https://doi.org/10.1130/G31639.1 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 Description of the three-dimensional geometry and grain-size patterns of fluvial deposits and their relationship to the morphodynamics of the river has been an elusive objective in sedimentology, hindered by limited exposure and the time scale of fluvial dynamics. In small-scale physical models the time scales are short enough to map river morphology and sedimentology during significant (and continuous) morphological development of the river and its deposits, especially for braided rivers. Using close-range digital photogrammetry, the dynamics of the river morphology, and resulting deposit geometry and sedimentology, were captured using digital elevation model differencing techniques, combined with automated grain-size mapping from image texture analysis. Using these novel methods we show the temporal development and characteristics of braided river deposit geometry, and, for the first time, map the characteristics and development of the basal surface of braided river deposits in relation to river morphodynamics and formative processes. The basal surface has considerable relief, wide variation in grain size similar to that of the river as a whole, develops progressively over time by switching of channels producing adjacent patches and ribbons of basal incision of different ages, and is only partially related to bed scour associated with laterally migrating channel confluences You do not have access to this content, please speak to your institutional administrator if you feel you should have access.