Quaternary Paleoceanography of the Arctic Gateway Region Based on Isotopic and Faunal Analysis of Foraminifera

基于有孔虫同位素和动物区系分析的北极门户地区第四纪古海洋学

• 批准号: 9423485
• 负责人: Benjamin Flower
• 金额: $ 9.75万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-04-15 至 1997-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9423485&HistoricalAwards=false
• 关键词: Quaternary; Paleoceanography; Arctic; Gateway; Region

9423485 Flower This award supports a project to study sediments from the Arctic Gateway region. Surface water exchange through the Arctic Gateway at Fram Strait accounts for about 90% of the Arctic heat budget and so this region may have played a major role in glacial-interglacial Arctic climates during the Quaternary. The major objectives of this research include documenting the Quaternary history of Arctic climates and investigating the role of surface to intermediate water exchange through the Arctic Gateway in late Quaternary glacial-interglacial Arctic climates. Two sedimentary sequences on the Yermak Plateau, recently drilled by Leg 151 of the Ocean Drilling Program, provide the first opportunity for high-resolution studies of the Arctic Gateway region. This project will generate high-resolution isotopic and faunal records based on planktonic and benthic foraminifera from sites 910 and 911 forming a depth transect on the Yermak Plateau (at 556 and 902 m water depth, respectively). Planktonic records, with about 4,000 year resolution, will be spliced together from both sites to form a composite record of surface water environments throughout the Brunhes Epoch (late Quaternary to present). Benthic records, with about 10,000 year resolution, will also be compiled. When combined, these records will allow detailed comparison of surface waters to intermediate water environments for areas with 550 and 900 m water depths. These data will allow detailed reconstruction of surface to intermediate water hydrography during the Brunhes Epoch. Extended records at site 911A will provide the first long-term, high-resolution records of Arctic surface and intermediate water environments throughout the Quaternary. These hydrographic interpretations of the integrated isotopic and faunal records will test hypotheses about the role of this oceanic gateway in regional and global climatic change. The results will bear on the importance of meridional heat transport by Arctic Gateway surface currents during intervals of global warmth and during important climatic transitions. The intervals of greatest interest include the mid-Quaternary climatic transition from about 1.2-0.6 Ma, and glacial-interglacial cycles of the Brunhes Epoch. The records obtained will greatly improve our understanding of the influence of the Arctic Gateway region on the global climate system during the Quaternary. In particular, this work will examine the role of Arctic Gateway paleoceanography in the Quaternary glacial evolution of the Northern Hemisphere. Lastly, it should provide insights into the future response of Arctic climates to projected global warming.

9423485花该奖项支持一个研究北极门户地区沉积物的项目。 通过北极门户在弗拉姆海峡的地表水交换约占90%的北极热量预算，因此该地区可能发挥了重要作用，在第四纪的冰川间冰期北极气候。 这项研究的主要目标包括记录北极气候的第四纪历史，并调查通过北极门户在晚第四纪冰期-间冰期北极气候中的地表水到中层水交换的作用。 大洋钻探计划第151航次最近在叶尔马克高原钻探的两个沉积序列为北极门户地区的高分辨率研究提供了第一次机会。 该项目将根据在耶尔马克高原形成一个深度断面的910和911站点（水深分别为556米和902米）的浮游有孔虫和底栖有孔虫，生成高分辨率同位素和动物群记录。 浮游生物记录，约4,000年的分辨率，将拼接在一起，从两个网站，形成一个复合记录的地表水环境在整个布鲁赫时代（晚第四纪至今）。 还将汇编分辨率约为10 000年的海底记录。 当这些记录结合起来时，就可以对水深为550米和900米的地区的表层沃茨和中层水环境进行详细的比较。 这些数据将允许详细重建的表面，中间水水文在布鲁赫时代。 911 A站点的扩展记录将提供整个第四纪北极地表和中间水环境的第一个长期高分辨率记录。 这些综合同位素和动物记录的水文解释将测试关于这一海洋门户在区域和全球气候变化中的作用的假设。 结果将承担在全球变暖的间隔期间，在重要的气候转变的重要性，通过北极门户表面电流的纬向热传输。 最感兴趣的间隔包括从大约1.2-0.6 Ma的中第四纪气候转变，以及Brunhes时代的冰川-间冰期循环。 所获得的记录将大大提高我们对北极门户地区第四纪对全球气候系统影响的认识。 特别是，这项工作将研究北极门户古海洋学在北方半球的第四纪冰川演变的作用。 最后，它应该提供关于北极气候对预计的全球变暖的未来反应的见解。