Multi-proxy geochemical analyses of Indus submarine fan sediments sampled by IODP Expedition 355; implications for sediment provenance and palaeoclimate reconstructions

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Author(s): Bratenkov, Sophia; George, Simon C.; Bendle, James; Liddy, Hannah; Clift, Peter D.; Pandey, Dhananjai K.; Kulhanek, Denise K.; Ando, Sergio; Tiwari, Manish; Khim, Boo-Keun; Griffith, Elizabeth; Steinke, Stephan; Suzuki, Kenta; Lee, Jongmin; Newton, Kate; Tripathi, Shubham
Integrated Ocean Drilling Program, Expedition 355 Scientific Party
Author Affiliation(s): Primary:
Macquarie University, North Ryde, Sydney, NSW, Australia
University of Birmingham, United Kingdom
University of Southern California, United States
Louisiana State University, United States
National Centre for Antarctic and Ocean Research, Vasco da Gama, India
Texas A&M University, United States
University of Milano Bicocca, Italy
Pusan National University, South Korea
University of Texas at Arlington, United States
MARUM, University of Bremen, Bremen, Germany, (11) Hokkaido University, Japan
Volume Title: European Geosciences Union general assembly 2016
Source: Geophysical Research Abstracts, Vol.18; European Geosciences Union general assembly 2016, Vienna, Austria, April 17-22, 2016. Publisher: Copernicus GmbH on behalf of the European Geosciences Union (EGU), Katlenburg-Lindau, Germany. ISSN: 1029-7006
Note: In English
Summary: The interplay between the development of the Asian summer monsoon and the growth of mountains in South and Central Asia is perhaps the most compelling example of the relationship between climate and the solid Earth. Understanding this relationship is crucial in the context of understanding past changes and for predicting future impacts in the Monsoon region. Both rapid and gradual mountain uplift influence the surrounding environments and regional climate. The sedimentary record of the Indus Fan offers a unique opportunity to study the climatic changes that occurred in South Asia and their link to the intensity of the erosion during the late Cenozoic. Although some paleoclimate reconstructions in the region can be partly addressed by studies onshore, the dominance of erosional processes in such a mountainous region ensures such records are fragmentary and limited in coverage. Thus ocean drilling is the best way to recover long sequences and to test the possible relations among mountain uplift, erosion, sediment deposition and climate (including carbon burial, chemical weathering and CO2 drawdown). The sediments and sedimentary rocks from the Indian continental margin, adjoining the Arabian Sea, were drilled during the International Ocean Discovery Program (IODP) Expedition 355. Drilling operations at Site U1456 penetrated through 1109.4 m of sediment and sedimentary rocks. The oldest sediment recovered at this site is dated to 13.5-17.7 Ma, with about 390 m of mass transport deposit. This study provides a multiproxy approach for paleoenvironmental reconstructions in the Arabian Sea area. We use a wide variety of organic geochemical data coupled with inorganic chemistry, mineralogy, and isotopic analyses. For direct comparison among various data sets, we divided whole round residue from the interstitial water samples among different laboratories, with each receiving 50-300 g (dry mass). The preliminary results include initial sediment provenance data based on bulk petrography and heavy mineral analysis, geochemical data, isotope composition, and biomarker analysis. Preliminary organic geochemistry data suggest an increase of terrigenous organic matter input into sediment starting around 10.5 Ma, with a strong decrease in the last 1 Ma. Moreover, the detailed analyses of the glyceryl dialkyl glyceryl tetraether (GDGT) and alkenone lipids provide the first sea surface temperature (SST) reconstructions in the region. These data indicate decreasing SST from the middle Miocene Climatic Optimum until today. This research provides an exceptional opportunity to apply a multiproxy approach to understand sediment provenance, erosional processes, and paleoclimate evolution in the eastern Arabian Sea. [Copyright Author(s) 2016. CC Attribution 3.0 License:]
Year of Publication: 2016
Research Program: IODP Integrated Ocean Drilling Program
IODP2 International Ocean Discovery Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Arabian Sea; Cenozoic; Chemical composition; Cores; Expedition 355; Geochemistry; IODP Site U1456; Indian Ocean; Indus Fan; International Ocean Discovery Program; Marine sediments; Paleoclimatology; Reconstruction; Sediments; Upper Cenozoic
Coordinates: N163717 N163718 E0685021 E0685020
Record ID: 2019072104
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from European Geosciences Union, Munich, Germany