Slumps and their deposits in fan delta front and slope

Abstract

Research Article| January 01, 1984 Slumps and their deposits in fan delta front and slope George Postma George Postma 1Universitetet I Bergen, Geologisk Institutt AVD. A, Allégaten 41, 5000 Bergen, Norway Search for other works by this author on: GSW Google Scholar Author and Article Information George Postma 1Universitetet I Bergen, Geologisk Institutt AVD. A, Allégaten 41, 5000 Bergen, Norway Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1984) 12 (1): 27–30. https://doi.org/10.1130/0091-7613(1984)12<27:SATDIF>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 MailTo Tools Icon Tools Get Permissions Search Site Citation George Postma; Slumps and their deposits in fan delta front and slope. Geology 1984;; 12 (1): 27–30. doi: https://doi.org/10.1130/0091-7613(1984)12<27:SATDIF>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 SocietyGeology Search Advanced Search Abstract A sedimentation model of subaqueous fan deltas dominated by conglomeratic mass flow has been developed from side-scan sonar images of some modern arctic deltas and some fossil examples from southeast Spain. These modern and ancient examples show slide scars in the delta-front sediments and downgoing troughs on the delta slope. The troughs are separated by erosion remnants and (partly) filled with slumped material from the slide scars, from which bed sequences of ancient fan deltas were studied in detail. Some of the relatively small slump deposits (ca. 50,000 m3) show an increase from massive toward stratified bedding away from the slide scar. With respect to the relationship of massive and stratified sediments, a new process called gravity-winnowing has been inferred from experiments and field studies. In this case the stratification occurs by repeated slumping by means of small grain flows and turbulent flows from the just-deposited and unstable head of the debris. 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.