Biostratigraphic subdivision and correlation of upper Maastrichtian sediments from the Atlantic Coastal Plain and Blake Nose, western Atlantic
Jean M. Self-Trail, 2001. "Biostratigraphic subdivision and correlation of upper Maastrichtian sediments from the Atlantic Coastal Plain and Blake Nose, western Atlantic", Western North Atlantic Palaeogene and Cretaceous Palaeoceanography, Dick Kroon, R. D. Norris, A. Klaus
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Detailed biostratigraphic analyses of nine cores from the Atlantic Coastal Plain and two cores from the Blake Nose, western Atlantic Ocean, provide the basis for subdivision and correlation of upper Maastrichtian sediments along a shallow- to deep-water transect. The calcareous nannofossil record from these sites shows distinct differences between the middle to outer neritic Coastal Plain sediments and the lower to upper bathyal Blake Nose sediments. Micula murus, a reliable marker species for low- to mid-latitude sites, is shown herein to respond to differing palaeoenvironmental conditions of nearshore v. open-ocean sites. Its usefulness as a biostratigraphic marker for neritic sediments is called into question. The last appearance datum of Ceratolithoides kamptneri is documented as a reliable biozone marker for latest Maastrichtian time (within CC26b) in this region. The evolutionary radiation and resulting biostratigraphic utility of species of Ceratolithoides, Lithraphidites and Micula is discussed in detail, and their first and last occurrences are tied to magneto-stratigraphic chrons where possible. Ceratolithoides amplector, Ceratolithoides indiensis and Ceratolithoides pricei are shown to be useful, biostratigraphically, in sediments deposited under bathyal conditions. Several species of Lithraphidites (Lithraphidites? charactozorro, Lithraphidites kennethii and Lithraphidites grossopectinatus) can be used to further subdivide upper Maastrichtian sediments at both neritic and bathyal localities. The first and last occurrence of Micula praemurus in Zones CC25a and CC26a, respectively, are shown to be useful biostratigraphic datum points.
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Western North Atlantic Palaeogene and Cretaceous Palaeoceanography
Palaeogene and Cretaceous palaeoceanography has been the focus of intense international interest in the last few years, spurred by deep ocean drilling at Blake Nose in the North Atlantic as well as the need to use past climate change as input for modelling future climate change. This book brings together a number of review papers that describe ancient oceans and unique events in the Earth’s climatic history and evolution of biota. The papers show evidence of periods characterized by exceptional global warmth such as the Late Palaeocene Thermal Maximum and Cretaceous anoxic events. Geochemical records and modelling will make the reader aware that these periods were forced by greenhouse gases. This information is essential for understanding the response of the ocean—climate system to the current input of fossil fuels. In this sense, the book contributes to the understanding of fundamental aspects of Earth’s climate, the carbon cycle, and marine ecosystems. A number of papers describe massive mass wasting deposits resulting from the energy released by the bolide impact at the Cretaceous—Tertiary boundary as well as the geochemistry of the boundary itself. Additional papers cover aspects of cyclostratigraphy and biostratigraphy of Palaeogene and Cretaceous records.
This book will be of interest to a broad audience of Earth Scientists interested in Palaeogene—Cretaceous palaeoceanography, extreme climate modelling, Cretaceous—Tertiary boundary, Late Palaeocene Thermal Maximum, Cretaceous anoxic events, as well as those specifically interested in radiolarian, dinoflagellate and coccolithophorid stratigraphy.