New oxygen isotope evidence for long-term Cretaceous climatic change in the Southern Hemisphere

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doi: 10.1130/0091-7613(1999)027<0699:NOIEFL>2.3.CO;2
Author(s): Clarke, Leon J.; Jenkyns, Hugh C.
Author Affiliation(s): Primary:
University of Oxford, Department of Earth Sciences, Oxford, United Kingdom
Volume Title: Geology (Boulder)
Source: Geology (Boulder), 27(8), p.699-702. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0091-7613 CODEN: GLGYBA
Note: In English. With GSA Data Repository Item 9957. 24 refs.; illus., incl. 2 tables, sketch map
Summary: A new composite δ18O record, generated from calcareous fine-fraction and bulk sediments from the Exmouth Plateau, details long-term Cretaceous climatic change at mid-latitudes in the Southern Hemisphere. Assessment of new and previously published δ18O data indicates that a mid-Cretaceous global climatic optimum was achieved sometime between the time of the Cenomanian-Turonian boundary and the middle Turonian, when surface-ocean paleotemperatures were the highest of the past 115 m.y. Periods of cooling and warming that reversed the general patterns were superimposed on long-term Aptian-Turonian warming and Turonian-Maastrichtian cooling trends, respectively. Extrapolation of Southern Hemisphere paleotemperature trends to Maastrichtian paleotemperature data from a low-latitude Pacific guyot implies that maximum mid-Cretaceous low-latitude paleotemperatures could have been in excess of 33 °C.
Year of Publication: 1999
Research Program: ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 12 Stratigraphy, Historical Geology and Paleoecology; Carbonate rocks; Chalk; Clastic rocks; Claystone; Climate change; Cretaceous; Exmouth Plateau; Geochemistry; Indian Ocean; Isotope ratios; Isotopes; Leg 122; Leg 123; Marine environment; Mesozoic; O-18/O-16; ODP Site 762; ODP Site 763; ODP Site 766; Ocean Drilling Program; Oxygen; Paleoclimatology; Paleotemperature; Sea-surface temperature; Sedimentary rocks; Southern Hemisphere; Stable isotopes
Coordinates: S195315 S195314 E1121515 E1121514
S203512 S203511 E1121232 E1121231
S195556 S195555 E1102715 E1102714
Record ID: 1999055482
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States