Geochemical Analysis of Ostracodes from the Arctic Ocean: Last Glacial Maximum to Present

9400250贝克研究项目由北极系统科学（ARCSS）全球变化研究项目资助，由海洋科学部和极地项目办公室联合赞助。研究将围绕一个独特的和密集的，多学科的研究考察北冰洋的部分，从未被广泛研究过。1994年美国/加拿大北冰洋科是与加拿大的一项合作努力，1994年夏季将有大约60名科学家乘坐加拿大和美国的破冰船。nsf资助的项目将集中于水文、生物学、古和海冰研究。从北冰洋几个地区收集的数据将是有史以来的首批数据之一，这些数据将与提高我们对北极如何成为全球气候条件变化的一个指标，以及它如何影响温带海洋和地区的物理、化学和生物特征的理解高度相关。这项工作是古海洋学合作项目的一个组成部分。通过测量一种丰富的浮游动物外骨骼的分布和某些化学特征，将重建北极盆地的气候历史。介形虫分泌壳的速度很快，从而记录了周围水的瞬时物理和化学性质。再加上频繁的蜕皮，可确定的镁方解石成分，以及灵敏的分析方法，使它们成为记录岩心沉积物中古海洋学的首选。活塞和箱形岩心沉积物中的介形虫阀将通过筛网洗涤分离，鉴定并进行元素和稳定同位素分析。钙采用火焰原子吸收分光光度法测定，锶和镁采用石墨炉原子吸收分光光度法测定。将进行大约1000次这样的测量，以重建北冰洋深处的古环流和底水古温度，并将这些因素与古生产力、溶解氧、海冰覆盖和从末次极大期到现在的其他参数联系起来。＊＊＊

9400250 Baker Research supported by this grant is under the auspices of the Arctic Systems Science (ARCSS) Global Change Research Program and is jointly sponsored by the Division of Ocean Sciences and the Office of Polar Programs. The research will be centered around a unique and intensive, multidisciplinary research expedition to parts of the Arctic Ocean that have never been extensively studied. The 1994 U.S./Canada Arctic Ocean Section is a collaborative effort with Canada that will involve approximately 60 scientists on a Canadian and a U.S. icebreaker during summer 1994. NSF-funded projects will focus on hydrography, biology, paleo-, and sea-ice studies. Data collected will be amongst the first ever from several regions of the Arctic Ocean and will be highly relevant to improving our understanding of how the Arctic is an indicator of changing global climate conditions and how it affects the physical, chemical, and biological features of the more temperate oceans and regions. This work is a component of the collaborative paleooceanographic program. A climatic history of the Arctic Basin will be reconstructed by measuring the distribution within the sediments and certain chemical characteristics of the exoskeleton of an abundant zooplankton animal. Ostracodes secrete shells rapidly, thereby recording instantaneous physical and chemical properties of the surrounding water. This combined with frequent molts, definable magnesium-calcite compositions, and sensitive analytical methods make them a prime candidate for recording paleoceanography in cored sediments. Ostracode valves from sediments in piston and box cores will be separated by washing over a sieve, identified, and subjected to elemental and stable isotopic analysis. Calcium will be measured using flame atomic absorption spectrophotometry while strontium and magnesium will be quantified by graphite furnace atomic absorption spectrophotometry. Approximately 1,000 such measurements will be made in an effort to reconstruct deep Arctic Ocean paleocirculation and bottom water paleotemperatures, and to relate these factors to paleoproductivity, dissolved oxygen, sea ice coverage, and other parameters of the period from the last glacial maximum to the present. ***