Sediment gravity flow frequency offshore central California diminished significantly following the Last Glacial Maximum

• Published in: Frontiers in Marine Science Vol. 10
• Main Authors: Dobbs, Stephen C., Paull, Charles K., Lundsten, Eve M., Gwiazda, Roberto, Caress, David W., McGann, Mary, Coholich, Marianne M., Walton, Maureen A. L., Nieminski, Nora M., McHargue, Tim, Graham, Stephan A.
• Format: Journal Article
• Language: English
• Published: Lausanne Frontiers Research Foundation 16-02-2023; Frontiers Media S.A
• Subjects: Autonomous underwater vehicles; Bathymetry; Carbon; Castles & palaces; Continental shelves; Core analysis; Energy management; Grain size; Gravity flow; Holocene; Laboratories; Last Glacial Maximum; marine geology; Offshore; offshore California; Open source software; Pleistocene; Radiocarbon dating; Reference materials; Ridges; Sea level; Sediment; Sediment gravity flows; Sediments; Stable isotopes; submarine channels; Surveying; Turbidity; San Simeon California; United States > US; California
• ISSN: 2296-7745; 2296-7745
• DOI: 10.3389/fmars.2023.1099472

A high-resolution multibeam survey from a portion of the San Simeon Channel (offshore Morro Bay, California) captured a zone of recurring troughs and ridges adjacent to prominent submarine meander bends. Through an integrated study using surveying data, sediment core analysis, radiocarbon dating, and stable isotope measurements, we hypothesize that turbidity current event frequency was higher during the late Pleistocene than at present conditions. We speculate that the rise in sea-level following the Last Glacial Maximum sequestered sedimentation largely to the shelf during the Holocene. This work suggests that the occurrence of sediment gravity flows in this region, particularly away from any submarine channels, is appreciably lower than at times of continental shelf subaerial exposure.