Astronomically tuned Plio-Pleistocene benthic δ18O record from South China Sea and Atlantic-Pacific comparison

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doi: 10.1016/S0012-821X(02)00923-8
Author(s): Tian Jun; Wang Pinxian; Cheng Xinrong; Li, Qianyu
Author Affiliation(s): Primary:
Tongji University, Laboratory of Marine Geology, Shanghai, China
Other:
University of Adelaide, Australia
Volume Title: Earth and Planetary Science Letters
Source: Earth and Planetary Science Letters, 203(3-4), p.1015-1029. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0012-821X CODEN: EPSLA2
Note: In English. 40 refs.; illus., incl. 3 tables, sketch map
Summary: Based on benthic foraminiferal δ18O from ODP Site 1143, a 5-Myr astronomical timescale for the West Pacific Plio-Pleistocene was established using an automatic orbital tuning method. The tuned Brunhes/Matuyama paleomagnetic polarity reversal age agrees well with the previously published age of 0.78 Ma. The tuned ages for several planktonic foraminifer bio-events also agree well with published dates, and new ages for some other bio-events in the South China Sea were also estimated. The benthic δ18O from Site 1143 is highly coherent with the Earth's orbit (ETP) both at the obliquity and precession bands for the last 5 Myr, and at the eccentricity band for the last 2 Myr. In general, the 41-kyr cycle was dominant through the Plio-Pleistocene although the 23-kyr cycle was also very strong. The 100-kyr cycle became dominant only during the last 1 Myr. A comparison of the benthic δ18O between the Atlantic (ODP 659) and the East and West Pacific (846 and 1143) reveals that the Atlantic-Pacific benthic oxygen isotope difference ratio (Δδ18OAtl-Pac) displays an increasing trend in three time intervals: 3.6-2.7 Ma, 2.7-2.1 Ma and 1.5-0.25 Ma. Each of the intervals begins with a rapid negative shift in Δδ18OAtl-Pac, followed by a long period with an increasing trend, corresponding to the growth of the Northern Hemisphere ice sheet. This means that all three intervals of ice sheet growth in the Northern Hemisphere were accompanied at the beginning by a rapid relative warming of deep water in the Atlantic as compared to that of the Pacific, followed by its gradual relative cooling. This general trend, superimposed on the frequent fluctuations with glacial cycles, should yield insights into the processes leading to the boreal glaciation. Cross-spectral analyses of the Δδ18OAtl-Pac with the Earth"s orbit suggests that after the initiation of Northern Hemisphere glaciation at about 2.5 Ma, obliquity rather than precession had become the dominant force controlling the vertical structure or thermohaline circulation in the paleo-ocean. Abstract Copyright (2002) Elsevier, B.V.
Year of Publication: 2002
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Anomalinidae; Atlantic Ocean; Benthic taxa; Biostratigraphy; Brunhes Chron; Buliminacea; Cassidulinacea; Cenozoic; Chemostratigraphy; Cibicidoides; Cibicidoides wuellerstorfi; Climate forcing; Correlation; Cycles; Eccentricity; Faunal list; Foraminifera; Geochemistry; Glacial geology; Glaciation; Globigerinacea; Globigerinidae; Globigerinoides; Globigerinoides ruber; Ice sheets; Invertebrata; Isotope ratios; Isotopes; Leg 108; Leg 138; Leg 184; Magnetostratigraphy; Marine sediments; Matuyama Chron; Microfossils; Neogene; North Pacific; Northern Hemisphere; Northwest Pacific; O-18/O-16; ODP Site 1143; ODP Site 659; ODP Site 846; ODP Site 849; Obliquity of the ecliptic; Ocean Drilling Program; Orbital forcing; Oxygen; Pacific Ocean; Paleo-oceanography; Paleocirculation; Paleoclimatology; Planktonic taxa; Pleistocene; Pliocene; Precession; Protista; Quaternary; Rotaliina; Sedimentation rates; Sediments; South China Sea; Stable isotopes; Tertiary; Thermohaline circulation; Time scales; Upper Cenozoic; Upper Quaternary; Uvigerina; Uvigerina peregrina; Uvigerinidae; West Pacific
Coordinates: N092143 N092143 E1131707 E1131707
N001058 N001100 W1103110 W1103111
S030549 S030541 W0904904 W0904906
N180437 N183438 W0210134 W0210135
Record ID: 2003006779
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands