Neogene to Quaternary Central Arctic Ocean dinoflagellate cyst stratigraphy and polar paleoceanography

IODP Leg 302 （ACEX: Arctic corcoration Expedition）在对北纬高纬度地区长期被冰覆盖的北冰洋中部的钻探岩芯进行科学勘探时首次恢复。将建立新近系至第四纪沉积物的鞭毛藻囊生物地层学，并与磁地层学进行校正，为可能与欧亚盆地板块构造和/或古气候发展以及罗蒙诺索夫海岭沉降有关的孔和迄今为止的裂缝提供基本的年龄控制。鞭毛藻囊和其他水生形态将进行定量分析，以揭示具有全球古气候意义的时期和事件的时间和结构。为了确定北冰洋对全球气候变化的响应，将重建某些新近纪时间片的海洋表面条件（温度、盐度、海冰覆盖持续时间）的变率和来自环北极陆地地区的淡水流量。最后两个冰期/间冰期旋回，海相间冰期同位素阶段1、5、11，中更新世革命，中上新世暖期和随后北半球主要冰期的开始，以及中中新世热最佳期。

IODP Leg 302 (ACEX: Arctic Coring Expedition) recovered for the first time in the scientific exploration of the high northern latitudes drill cores from the perennially ice-covered Central Arctic Ocean. A dinoflagellate cyst biostratigraphy of the Neogene to Quaternary sediments will be established and calibrated versus magnetostratigraphy to provide basic age control for the holes and to date hiatuses that are probably related to the plate tectonic and/or paleoclimate development of the Eurasia Basin and the subsidence of Lomonosov Ridge. Dinoflagellate cysts and other aquatic palynomorphs will be analysed quantitatively to unravel the timing and structure of periods and events that are of global paleoclimate significance. The variability of sea-surface conditions (temperature, salinity, duration of sea-ice cover) and the discharge of freshwater from the circum-arctic land areas will be reconstructed for certain Neogene time-slices to identify the response of the Arctic Ocean to global climate change: the last two glacial/ interglacial cycles, the marine interglacial isotope stages 1, 5, 11, the mid-Pleistocene Revolution, the mid-Pliocene warm period and the subsequent inception of major glaciations in the northern hemisphere, and the mid- Miocene thermal optimum.