Flume study of knickpoint development in stratified sediment

Abstract

Research Article| January 01, 1976 Flume study of knickpoint development in stratified sediment W. N. HOLLAND; W. N. HOLLAND 1Department of Geography, University of Sydney, New South Wales 2006, Australia Search for other works by this author on: GSW Google Scholar G. PICKUP G. PICKUP 1Department of Geography, University of Sydney, New South Wales 2006, Australia Search for other works by this author on: GSW Google Scholar Author and Article Information W. N. HOLLAND 1Department of Geography, University of Sydney, New South Wales 2006, Australia G. PICKUP 1Department of Geography, University of Sydney, New South Wales 2006, Australia Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1976) 87 (1): 76–82. https://doi.org/10.1130/0016-7606(1976)87<76:FSOKDI>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation W. N. HOLLAND, G. PICKUP; Flume study of knickpoint development in stratified sediment. GSA Bulletin 1976;; 87 (1): 76–82. doi: https://doi.org/10.1130/0016-7606(1976)87<76:FSOKDI>2.0.CO;2 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 SocietyGSA Bulletin Search Advanced Search Abstract In a flume study of knickpoint development in stratified sediment, two thin sand beds were intercalated between beds of cohesive material. The sand beds acted as knickpoint-forming horizons on which stepped knickpoints were developed and maintained as they moved upstream, creating an apparently stable form consisting of a channel-in-channel system. The system had four basic elements: (1) an aggraded reach upstream of the knickpoint, terminating on the downstream end at a fill-incision transition zone; (2) an oversteepened reach just above the knickpoint face; (3) the knickpoint face; and (4) an incising reach, often covered by moving sediment between successive knickpoints.Apparently the presence of a knickpoint-forming horizon reduces knickpoint retreat rates, which were much lower in this study than those observed in an experiment with cohesive material but no intercalated sand beds and a similar discharge. Also, the channel-in-channel system that results from stratification is apparently fairly insensitive to the effects of changing discharge. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.