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

9400250贝克研究由该赠款支持是在北极系统科学（ARCSS）全球变化研究计划的主持下，由海洋科学司和极地计划办公室联合赞助。 该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地区，从来没有被广泛研究。 1994年美国/加拿大北冰洋科是与加拿大的一项合作努力，将有大约60名科学家在1994年夏季乘坐一艘加拿大和一艘美国破冰船。 NSF资助的项目将侧重于水文学、生物学、古生物学和海冰研究。 收集的数据将是北冰洋几个地区有史以来的第一批数据，将有助于我们更好地了解北极如何成为全球气候变化的指标，以及它如何影响更温和的海洋和地区的物理，化学和生物特征。 这项工作是古海洋学合作计划的一个组成部分。 将通过测量沉积物内的分布和一种丰富的浮游动物外骨骼的某些化学特性，重建北极盆地的气候史。 介形虫迅速分泌贝壳，从而记录周围水的瞬时物理和化学性质。 这与频繁的蜕皮，可定义的镁方解石成分，和敏感的分析方法相结合，使他们成为记录在取芯沉积物古海洋学的主要候选人。 将通过在筛子上洗涤，从活塞和盒状岩心中的沉积物中分离介形虫阀，进行鉴定，并进行元素和稳定同位素分析。 钙将采用火焰原子吸收分光光度法测定，而锶和镁将采用石墨炉原子吸收分光光度法定量。 将进行大约1 000次这样的测量，以重建北冰洋深层古环流和底层水古温度，并将这些因素与古生产力、溶解氧、海冰覆盖率以及从末次盛冰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. ***