Megaflood erosion and meltwater plumbing changes during last North American deglaciation recorded in Gulf of Mexico sediments

Research Article| July 01, 1998 Megaflood erosion and meltwater plumbing changes during last North American deglaciation recorded in Gulf of Mexico sediments Paul A. Brown; Paul A. Brown 1Department of Geological Sciences and Marine Science Institute, University of California, Santa Barbara, California 93106 Search for other works by this author on: GSW Google Scholar James P. Kennett James P. Kennett 1Department of Geological Sciences and Marine Science Institute, University of California, Santa Barbara, California 93106 Search for other works by this author on: GSW Google Scholar Author and Article Information Paul A. Brown 1Department of Geological Sciences and Marine Science Institute, University of California, Santa Barbara, California 93106 James P. Kennett 1Department of Geological Sciences and Marine Science Institute, University of California, Santa Barbara, California 93106 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1998) 26 (7): 599–602. https://doi.org/10.1130/0091-7613(1998)026<0599:MEAMPC>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 Email Permissions Search Site Citation Paul A. Brown, James P. Kennett; Megaflood erosion and meltwater plumbing changes during last North American deglaciation recorded in Gulf of Mexico sediments. Geology 1998;; 26 (7): 599–602. doi: https://doi.org/10.1130/0091-7613(1998)026<0599:MEAMPC>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 Submicrometer variations in the median diameter of siliciclastic mud in Orca Basin, northern Gulf of Mexico, sensitively monitor Laurentide ice sheet runoff to the gulf during early stages of the last deglaciation. Grain-size data document a prominent pulse of very fine-grained sediment to the northern Gulf from 12.6 to 12.0 ka, corresponding with the well-known sea-surface meltwater spike in δ18O records. Meltwater megafloods at this time eroded and transported large volumes of clay to the Gulf via the Mississippi River system. The nonquartzose megaflood sediments appear to have been derived from clay-rich midcontinental terrace deposits rather than from glacial outwash supplied by the Laurentide ice margin. Sediment grain-size data, in combination with other terrigenous proxies (clay minerals and reworked calcareous nannofossils), indicate substantial variability in deglacial meltwater discharge and associated sediment load of meltwater runoff. This variability reflects changes in continental plumbing consistent with terrestrial records of North American deglaciation. 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.