Grain-size records at ODP site 1146 from the northern South China Sea; implications on the East Asian monsoon evolution since 20 Ma

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doi: 10.1007/s11430-007-0082-0
Author(s): Wan Shiming; Li Anchun; Stuut, Jan-Berend W.; Xu Fangjian
Author Affiliation(s): Primary:
Chinese Academy of Sciences, Institute of Oceanology, Qingdao, China
University of Bremen, Germany
Volume Title: Science in China. Series D, Earth Sciences
Source: Science in China. Series D, Earth Sciences, 50(10), p.1536-1547. Publisher: Springer, co-published with Science in China Press, Beijing, China. ISSN: 1006-9313
Note: In English. 63 refs.
Summary: 273 samples from Ocean Drilling Program (ODP) Site 1146 in the northern South China Sea (SCS) were analyzed for grain-size distribution using grain-size class vs. standard deviation method and end-member modeling algorithm (EMMA) in order to investigate the evolution of the East Asian monsoon since about 20 Ma. The ratio of two grain-size populations with the highest variability through time was used to indicate East Asian winter monsoon intensity relative to summer monsoon. The mass accumulation rate of the coarsest end member EM1 (eolian), resulting from EMMA, can be used as a proxy for winter monsoon strength and Asian inland aridity, and the ratio of EM1/(EM2+EM3) as a proxy of winter monsoon intensity relative to the summer monsoon. The combined proxies show that a profound enhancement of the East Asian winter monsoon strength and winter monsoon intensity relative to summer monsoon occurred at about 8 Ma, and it is possible that the summer monsoon simultaneously intensified with winter monsoon at 3 Ma. Our results are consistent with previous studies in loess, eolian deposition in the Pacific, radiolarians and planktonic foraminifera in the SCS. The phased uplift of the Tibetan Plateau may have played a significant role in strengthening the Asian monsoon at 8 Ma and 3 Ma.
Year of Publication: 2007
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Cenozoic; Clastic sediments; Distribution; Dust; East Asian Monsoon; Grain size; Leg 184; Marine sediments; Miocene; Monsoons; Neogene; North Pacific; Northwest Pacific; ODP Site 1146; Ocean Drilling Program; Pacific Ocean; Paleoclimatology; Paleoenvironment; Sediments; South China Sea; Tertiary; Transport; Upper Miocene; West Pacific; Wind transport
Coordinates: N192724 N192724 E1161622 E1161622
Record ID: 2017032875
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