Deep-sea biostratigraphy of prograding platform margins (Neogene, Bahamas): key evidence linked to depositional rhythm

New foraminiferal evidence from two boreholes on the paleoshelf and slope of western Great Bahama Bank has wide-ranging implications for understanding formation and evolution of carbonate-platform margins. The new data, abundant well-preserved planktic foraminifera, were obtained by disaggregating samples from intercalated pelagic layers and selected parts of thick hemipelagic limestone. The new data define six units in one hole and seven in the other, bracket the biozones present and their ages, indicate different sedimentation rates, and show that within the limits of biostratigraphic resolution the biozones are correlative between the holes. Most importantly, the revised ages show that the paleoshelf borehole probably penetrated the late Miocene rather than middle Miocene. -from Authors