CA Seabed

Naval and engineering applications in the deep sea require an improved, integrative understanding of the seabed that includes short-term changes driven by biological and hydrodynamic processes, as well as tools for remote sensing of seabed properties. Our interdisciplinary team proposes to test the overarching hypothesis that organic matter input to the deep sea drives biological processes that modify geotechnical and geoacoustic properties of the surface layer of sediments. In testing this hypothesis, we will explore the spatial and temporal variability and relationships among these properties within a highly productive region of the deep sea, the central California slope. This region experiences seasonal and interannual variability in organic matter and sediment deposition to the seabed and spatial variability in the infaunal community driven by oxic conditions and organic matter input. We plan to combine seasonal sampling of geological, geotechnical, geoacoustic, biological, and biogeochemical properties along a spatial gradient with high temporal resolution sampling of the bottom boundary layer and seabed surface. Our results will provide insight on the patterns of seabed properties and the mechanisms driving those patterns and will improve our ability to predict and remotely detect changes in deep sea sediments.