[MIS14-P12] Changes in composition of fossil diatoms from Ross Sea under gradual warming climate from MIS M2
Keywords:Diatom, The Southern Ocean, Paleoenvironment
International Ocean Discovery Program (IODP) Expedition 374 drilled five sites from Ross Sea continental shelf and rise to investigate WAIS evolution under warm climates. Site U1524A (74° 13.05’ S and 173° 37.98’ W, 2394 m water depth) drilled from continental rise, which lies beneath cascading Antarctic Bottom Water current, preserves high resolution Pliocene sediments. We present preliminary results of composition changes of diatom assemblages focusing on the ages from MIS M2 to warmer climate around the interval between 3.3 and 3.0 Ma. Diatom records including abundance changes in sea-ice indicator species and Chaetocerosresting spores contribute to evaluate the past sea-ice coverage, primary productivity, and vertical mixing in Pliocene warm condition.