Aspects of the late Quaternary paleoenvironmental and paleoceanographic history of Santa Monica Basin, southern California borderland

This dissertation explores the sedimentary record of climatic and environmental change in Santa Monica Basin, California during the late Quaternary (ca. 50 thousand years to the present). Specifically, modern canyon activity, climate related deep water fluctuations, and changes in the extent of the oxygen minimum zone (OMZ) were investigated through study of modern core-tops collected in the submarine canyons entering Santa Monica Basin and deep sea drilling cores collected at Ocean Drilling Program (ODP) Site 1015 in Santa Monica Basin. Techniques employed in this study included: (1) analyses of stable oxygen and carbon isotopic composition of benthic foraminiferal tests, (2) analyses of benthic foraminiferal assemblages, and (3) analyses of modern benthic foraminiferal assemblages in three of the canyons in Santa Monica Basin. These data were combined with and analyzed in the context of previously published data from the borderland including high-resolution isotopic and micropaleontologic records from ODP Site 893 in the adjacent Santa Barbara basin. Interpretation of down-core stratigraphic variations in isotopic values and quantitative microfaunal trends provide new insights into the late Pleistocene-Holocene circulation, climate variability, and sediment character and input to Santa Monica Basin. Data from modern core-tops shed light on the connections between activity in submarine canyons and the benthic foraminiferal faunas inhabiting the canyons of Santa Monica Basin.