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

9400250贝克研究由这笔赠款资助，由北极系统科学全球变化研究计划赞助，由海洋科学部和极地方案办公室联合赞助。这项研究将围绕着对北冰洋从未被广泛研究的部分进行一次独特的、密集的、多学科的研究考察。1994年美国/加拿大北冰洋部分是与加拿大的一项合作努力，将有大约60名科学家在1994年夏天在一艘加拿大破冰船和一艘美国破冰船上工作。NSF资助的项目将集中在水文地理学、生物学、古生物和海冰研究上。从北冰洋几个地区收集的数据将是有史以来最早的数据之一，对于增进我们对北极如何成为全球气候条件变化的指标以及它如何影响较温和海洋和地区的物理、化学和生物特征的理解，将具有非常重要的意义。这项工作是古海洋学合作计划的组成部分。通过测量沉积物中的分布和一种丰富的浮游动物外骨骼的某些化学特征，将重建北极盆地的气候历史。介形类迅速分泌贝壳，从而记录周围水域的瞬时物理和化学性质。这再加上频繁的蜕皮、可定义的镁方解石成分和灵敏的分析方法，使它们成为记录取芯沉积物中古海洋学的主要候选者。从活塞和盒状岩芯中的沉积物中分离出介形虫阀门，通过筛子洗涤，进行鉴定，并进行元素和稳定同位素分析。钙的测定采用火焰原子吸收光谱法，锶和镁的测定采用石墨炉原子吸收光谱法。将进行大约1,000次这样的测量，以努力重建北冰洋深海古环流和底层水古温度，并将这些因素与从最后一次冰盛期到现在的古生产力、溶解氧、海冰覆盖率和其他参数联系起来。***

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. ***