Eocene Arctic Ocean and earth's Early Cenozoic climate
Seasonal changes of the Arctic Ocean are an approximate microcosm of the present advanced interglacial climate of the Earth. A similar relationship has existed for several million years but was the Early Cenozoic Arctic Ocean an analog of Earth's climate, as well. Absence of polar ice during the Cretaceous is relatively well established. During the Cenozoic a worldwide decrease in mean annual ocean temperature resulted from such factors as altered oceanic circulation and lower atmospheric CO/sub 2/ levels. Limited Arctic Ocean data for the middle or late Eocene indicate the presence of upwelling conditions and accompanying high productivity of diatoms, ebridians, silicoflagellates and archaeomonads. During this interval, some seasonality is suggested from the varve-like nature of a single sediment core. However, the absence of drop stones or any ice-rafted sediment supports the idea of an open water, ice-free central Arctic Ocean during this time. Latest Cretaceous Arctic Ocean sediment is interpreted to represent approximately the same conditions as those suggested for the Eocene and together with that data suggest that the central Arctic Ocean was ice-free during part if not all of the first 20 my of the Cenozoic. Sediment representing the succeeding 30 my has not been recovered but by latest Miocene or earl Pliocene, ice-rafted sediment was accumulating, both pack ice and icebergs covered the Arctic Ocean reflecting cyclic glacial climate.
- Research Organization:
- Univ. of Wisconsin, Madison (USA)
- OSTI ID:
- 6654535
- Report Number(s):
- CONF-8510489-
- Journal Information:
- Geol. Soc. Am., Abstr. Programs; (United States), Vol. 17; Conference: 98. annual meeting of the Geological Society of America, Orlando, FL, USA, 28 Oct 1985
- Country of Publication:
- United States
- Language:
- English
Similar Records
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Related Subjects
ARCTIC OCEAN
PALEOCLIMATOLOGY
SEDIMENTS
STRATIGRAPHY
CRETACEOUS PERIOD
EOCENE EPOCH
FORAMINIFERA
GLACIERS
POPULATION DENSITY
PRODUCTIVITY
SEASONAL VARIATIONS
ANIMALS
CENOZOIC ERA
GEOLOGIC AGES
GEOLOGY
INVERTEBRATES
MESOZOIC ERA
MICROORGANISMS
PALEONTOLOGY
PROTOZOA
SARCODINA
SEAS
SURFACE WATERS
TERTIARY PERIOD
VARIATIONS
580100* - Geology & Hydrology- (-1989)