HR: 1340h
AN: PP23A-1398 [Abstracts]
TI: Orbitally-paced paleoproductivity variations in the Timor Sea and Indonesian Throughflow variability
during the last 460-ky
AU: * Kuhnt, W
EM: wk@gpi.uni-kiel.de
AF: Department of Geosciences, Christian-Albrechts-University, Olshausenstr. 40, Kiel, 24118
Germany
AU: Holbourn, A
EM: ah@gpi.uni-kiel.de
AF: Department of Geosciences, Christian-Albrechts-University, Olshausenstr. 40, Kiel, 24118
Germany
AU: Kawamura, H
EM: hkawamura@nature.sci.hokudai.ac.jp
AF: COE Neo-Science of Natural History, Division of Biological Sciences, Graduate School of Science,
Hokkaido University, North 10 West 8, Kita-ku, Sapporo, 060-0810
Japan
AU: Jian, Z
EM: zjiank@online.sh.cn
AF: Department of Marine Geology, Tongji University, Siping Rd. 1239, Shanghai, 200092
China
AU: Grootes, P
EM: pgrootes@leibniz.uni-kiel.de
AF: Leibniz Laboratory for Radiometric Dating and Stable Isotope Research,Christian-Albrechts-University,
Max-Eyth-Str. 11-13, Kiel, 24118
Germany
AU: Erlenkeuser, H
EM: herlenkeuser@leibniz.uni-kiel.de
AF: Leibniz Laboratory for Radiometric Dating and Stable Isotope Research,Christian-Albrechts-University,
Max-Eyth-Str. 11-13, Kiel, 24118
Germany
AU: Xu, J
AF: Department of Marine Geology, Tongji University, Siping Rd. 1239, Shanghai, 200092
China
AB:
A high-resolution ($\sim$ 1-2 ky) multi-proxy record from the Timor Sea in the easternmost Indian Ocean (IMAGES Core
MD01-2378, Lat. 13$ \deg$ 04.95' S, Long. 12$ \deg$ 47.27' E, 1783 m water depth) closely tracks changes in intermediate
water ventilation and paleoproductivity over the last 460 ky within one of the main outflow passages of the Indonesian
Throughflow. Spectral analysis of five different types of flux-based productivity proxies indicates spectral power
concentrated in the 100 ky (glacial-interglacial) and 23 ky and 19 ky (precessional) periods. The productivity indicators
are coherent and in phase with the precession controlled equatorial winter insolation and generally lead the benthic
$\delta$$^{18}$O record by 2-3 ky. At terminations, rising sea-level (driven by high latitude forcing) and decreasing NW
monsoon (driven by precessional forcing) probably triggered an intensification of the Indonesian Throughflow, stabilizing the
upper water column and prohibiting vertical mixing. Thus, productivity fluctuations in the Timor Sea over the last 460 ky
were strongly influenced by monsoonal flow patterns in the eastern equatorial Indian Ocean (23 and 19 ky) and were also
modulated by the intensity of the Indonesian Throughflow (100 ky).
DE: 9330 Australia
DE: 4870 Stable isotopes
DE: 4267 Paleoceanography
DE: 3030 Micropaleontology
DE: 1620 Climate dynamics (3309)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting