Late Cenozoic stable isotope stratigraphy and paleoceanography of DSDP sites from the east equatorial and central North Pacific Ocean

Author(s): Keigwin, L. D., Jr.
Author Affiliation(s): Primary:
Univ. R.I., Grad. Sch. Oceanogr., Kingston, R.I., United States
Volume Title: Earth and Planetary Science Letters
Source: Earth and Planetary Science Letters, 45(2), p.361-382. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0012-821X CODEN: EPSLA2
Note: In English. 68 refs.; illus. incl. tables
Summary: Stable isotopic analyses of Middle Miocene to Quaternary foraminiferal calcite from east equatorial and central north Pacific DSDP cores have provided much new information on the paleoceanography of the Pacific Neogene. Isotopic data from these cores indicates the following sequence of events related to continental glaciation: (1) A permanent Antarctic ice sheet developed late in the Middle Miocene. (2) The Late Miocene is marked by significant variation in delta O-18 of about 0.5 per mille throughout, indicating instability of antarctic ice cap size or bottom-water temperatures. (3)The early Pliocene was a time of relative stability in antarctic ice volume and bottom-water temperature. (4) Growth of permanent Northern Hemisphere ice sheets is inferred to have begun about 3 m.y. ago. (5) The late Pliocene is marked by one major glaciation or bottom-water cooling dated between about 2.1 to 2.3 m.y. (6) There is some evidence that the frequency of glacial-interglacial cycles increased at about 0.9 m.y. (Auth. mod.)
Year of Publication: 1979
Research Program: DSDP Deep Sea Drilling Project
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Benthic taxa; Biostratigraphy; C-13/C-12; Carbon; Carnegie Ridge; Cenozoic; Cocos Ridge; Cores; DSDP Site 157; DSDP Site 158; DSDP Site 310; Data; Deep Sea Drilling Project; East Pacific; Equatorial Pacific; Foraminifera; Glacial environment; Hess Rise; Interglacial environment; Invertebrata; Isotopes; Leg 16; Leg 32; Microfossils; North Pacific; Northwest Pacific; O-18/O-16; Oxygen; Pacific Ocean; Paleo-oceanography; Paleoclimatology; Paleoecology; Panama Basin; Planktonic taxa; Protista; Ratios; Stable isotopes; Stratigraphy; Upper Cenozoic; West Pacific
Record ID: 1980018821
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from the Antarctic Bibliography, United States

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