Ennyu, Atsuhito and Arthur, Michael A. (2004): Early to middle Miocene paleoceanography in the southern high latitudes off Tasmania

Leg/Site/Hole:
ODP 189
ODP 189 1170
ODP 189 1172
Identifier:
2005-035032
georefid
Creator:
Ennyu, Atsuhito
Pennsylvania State University, Department of Geosciences, University Park, PA, United States
author
Arthur, Michael A.
University of California at Santa Barbara, United States
author
Identification:
Early to middle Miocene paleoceanography in the southern high latitudes off Tasmania
2004
In: Exon, Neville F. (editor), Kennett, James P. (editor), Malone, Mitchell (editor), The Cenozoic Southern Ocean; tectonics, sedimentation, and climate change between Australia and Antarctica
American Geophysical Union, Washington, DC, United States
151
215-233
Paleoclimate proxy records from the southern high latitudes can provide key constraints on the possible role of ocean circulation as a cause of the middle Miocene global cooling event and the major development of the Antarctic cryosphere. Paleotemperature reconstructions based on (super 18) O values of calcareous plankton suggest that the warm-season, near-surface waters in the subantarctic around the site paleo-locations were warmer than today by 2-4 degrees C until about 14 Ma. The sea-surface temperatures were probably ameliorated by a warm current from the west that joined the Circum-Antarctic current. The cold season near-surface temperatures were unaffected during this interval. Based on the Miocene plankton and benthic stable isotope records, we suggest that the cooled surface waters in the southern high latitudes contributed to the increased rate of production and dominance of cold southern-component deepwater after ca. 14.5 Ma. (modif. j. abstr.)
English
Serial
Coverage:Geographic coordinates:
North:-43.5700
West:146.0200East: 149.5600
South:-47.1000
Stratigraphy; algae; Anomalinidae; Antarctic Circumpolar Current; Antarctic ice sheet; Antarctica; C-13/C-12; carbon; Cassidulinacea; Cenozoic; Cibicidoides; Cibicidoides wuellerstorfi; Coccolithophoraceae; Coccolithus; East Antarctic ice sheet; East Tasman Plateau; Foraminifera; Globigerina; Globigerina bulloides; Globigerinacea; Globigerinidae; Globoquadrina; Invertebrata; isotope ratios; isotopes; Leg 189; lower Miocene; marine environment; microfossils; middle Miocene; Miocene; nannofossils; nannoplankton; Neogene; O-18/O-16; ocean circulation; Ocean Drilling Program; ODP Site 1170; ODP Site 1172; Orbulina; Orbulina universa; Oridorsalis; Oridorsalis umbonatus; oxygen; Pacific Ocean; paleo-oceanography; paleocirculation; paleoclimatology; paleocurrents; paleosalinity; paleotemperature; plankton; Plantae; Protista; Rotaliina; seasonal variations; South Pacific; South Tasman Rise; Southern Ocean; Southwest Pacific; stable isotopes; subantarctic regions; Tasman Sea; Tasmanian Gateway; Tertiary; Tethys; West Pacific;
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