作者: R. Timothy Patterson , Charlotte A. Brunner , Rosemary Capo , Jeremy Dahl
DOI: 10.1017/S0022336000042190
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摘要: An interval of the Early to Middle Pleistocene history California Borderland was assessed using multivariate analysis foraminifera from Santa Barbara Formation at Bathhouse Beach, Barbara, California. A census 93 species benthic and nine planktonic compiled 11 samples shelly marls, silts, sands lower member. Most are rare only 38 comprise one percent or more population in samples. Paleoenvironment sea floor determined based on foraminifera. R-mode cluster defined five associations which similar those present-day banks terraces Borderland. Q-mode grouped into four biofacies characterize shallow near 50 meters water depth off-shore ridges deep averaging 150 depth. The stratigraphic succession indicates two transgressive cycles separated by an apparent disconformity between 7.5 8.9 above base section (between 3 4). Paleoceanography surficial waters interpreted Paleotemperature proportion sinistral dextral morphs encrusted, compact reticulate, globular Neogloboquadrina pachyderma. coiling show a warm about 12 5 6), cooler 24 10 11), intermediate paleotemperature topmost sample section. Changes assemblage do not coincide with inferred biofacies. Beach can be placed chronostratigraphically foraminiferal shifts strontium isotopic data. age range 400 900 Kyr brackets 600 assigned Lagoe Thompson (1988) pachyderma dominance CD9/CD8 boundary occurs midway section, 6.