XVI INQUA Congress

Paper No. 8
Presentation Time: 1:30 PM-4:30 PM

LAST GLACIAL MAXIMUM SEA-LEVEL OBTAINED FROM BONAPARTE GULF OF AUSTRALIA USING MICROPALAEONTOLOGICAL EVIDENCE


YOKOYAMA, Yusuke, Department of Earth and Planetary Sciences, Univ of Tokyo, 7-3-1 Hongo, Bldg#1, Bunkyo-ku, Tokyo, 113-0033, Japan, DE DECKKER, Patrick, Geology, The Australian National Univ, Canberra, ACT 0200, Australia and LAMBECK, Kurt, Research School of Earth Sciences, The Australian National Univ, Mills Road, Canberra, ACT0200, Australia, yokoyama@eps.s.u-tokyo.ac.jp

The region north of Australia, far away from former ice sheets and in a tectonically-stable margin, is ideally suited for sea-level reconstructions as glacio-hydro-isostatic effects are minimal. Thus, examination of ostracod and foraminifer remains, recovered from gravity core RS176/GC5 from Bonaparte Gulf, and which is located at 118m water depth, has permitted to reconstruct in detail the sea-level regression and transgression that coincided respectively with the on start and end of the Last Glacial Maximum (LGM). Our data further confirms that the lowest sea-level was locally at about 120m below present days sea-level. We provide further evidence of sea-level rise after 19,000 cal years BP of the order of 10 meters. Glacio-hydro-isostatic modeling was also conducted using these observations to draw palaeo-shore line maps. These maps are clearly demonstrated the drastic environmental transitions after the LGM through the Holocene.