Debris-flow benches: Dune-contact deposits record paleo-sand dune positions in north Panamint Valley, Inyo County, California

Abstract

Research Article| June 01, 1990 Debris-flow benches: Dune-contact deposits record paleo-sand dune positions in north Panamint Valley, Inyo County, California Suzanne Prestrud Anderson; Suzanne Prestrud Anderson 1Department of Geology and Geophysics, University of California, Berkeley, California 94720 Search for other works by this author on: GSW Google Scholar Robert S. Anderson Robert S. Anderson 2Earth Sciences Board, University of California, Santa Cruz, California 95064 Search for other works by this author on: GSW Google Scholar Geology (1990) 18 (6): 524–527. https://doi.org/10.1130/0091-7613(1990)018<0524:DFBDCD>2.3.CO;2 Article history first online: 02 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 Suzanne Prestrud Anderson, Robert S. Anderson; Debris-flow benches: Dune-contact deposits record paleo-sand dune positions in north Panamint Valley, Inyo County, California. Geology 1990;; 18 (6): 524–527. doi: https://doi.org/10.1130/0091-7613(1990)018<0524:DFBDCD>2.3.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 Debris flows debouching onto the alluvial fan at the north end of Panamint Valley, California, have been episodically impounded behind sand dunes, resulting in boulder-strewn, nearly flat topped deposits in irregular basins upslope of the dunes, whose upper surface is higher than the adjacent fan surface. Upslope migration of the dune field over and beyond these deposits eventually leaves them as debris-flow benches rising above the general fan surface. These features are therefore dune-contact forms, analogous to ice-contact forms such as kame terraces, in that both involve deposition against ephemeral barriers. Benches punctuate the alluvial-fan surface for 5 km downfan from the modern dune field. Clast seismic velocities of boulders on these benches indicate that bench ages increase monotonically with distance from the present dunes, implying that the dune field has migrated up the fan. Because the oldest bench is below the altitude of the highest pluvial lake shoreline in Panamint Valley (Gale Stage, ca. 50 ka) and slightly above the latest lakeshore (I Stage, ca. 14 ka), it seems likely that the dunes originated near the shore of the latest lake and have moved upfan at an average rate of 0.8 m/yr. 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.