Collaborative Research: GEOTRACES - 210Po and 210Pb distribution at Eastern Pacific Interface Regimes

合作研究：GEOTRACES - 东太平洋界面区域的 210Po 和 210Pb 分布

• 批准号: 1237108
• 负责人: Gillian Stewart
• 金额: $ 13.5万
• 依托单位: CUNY Queens College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1237108&HistoricalAwards=false
• 关键词: Collaborative; Research; GEOTRACES; 210Po; 210Pb

In 2013, a multi-institutional team of U.S. marine chemists and geochemists will launch a major expedition to the Pacific Ocean to map and study the distribution of trace elements and isotopes as part of the International GEOTRACES Program. Because of their proven value as natural tracers of both sedimentation dynamics and hydrodynamics in the sea, radioactive daughter isotopes in the natural U-Th radionuclide series will be of immense value to all GEOTRACES researchers. In particular the naturally-occurring Pb210/Po210 radioisotope pair would be useful for quantifying rates of particulate scavenging of other trace elements and isotopes of interest in the U.S.GEOTRACES Pacific campaign. This is because these two isotopes are themselves particle-reactive and radioactive, thus providing a natural clock for tracking the vertical transport of other particle-reactive substances.In this project, researchers at Wayne State University and CUNY Queens College will sample and analyze several hundred dissolved and particulate (large and small) samples for 210Po and 210Pb along the U.S.GEOTRACES Eastern South Pacific section. About two thirds of the samples will be focused at six so-called "super stations" (sites chosen for intensive study), half above the main thermocline and the other half down across the benthic nepheloid layer (the zone of suspended material extending several meters above the seafloor). The depths will be chosen according to regional atmospheric input, ecosystems, and coordinated with sampling by other researchers onboard. The other third will be taken within the hydrothermal plume in the vicinity of the East Pacific Rise. The data will be synthesized according to interface scavenging models by particle types (e.g. fine/colloidal, lithogenic and biogenic). As such, the proposed work will be closely coordinated with that of other U.S.GEOTRACES PIs funded to study other particle-reactive or dissolved trace elements and radionuclide isotopes during the campaign.BROADER IMPACTS: The broader impacts are closely linked to those of the GEOTRACES Program as a whole: to enhance (1) research infrastructure by providing a broad array of 210Po and 210Pb data useful for biogeochemical scavenging models, (2) education by mentoring graduate and undergraduate students, teaching by example from proposed research, (3) participation of under-represented students interested in careers in the geosciences, (4) research training of graduates in marine radiochemistry, and 5) public dissemination of results through publications, presentations, and on a dedicated public website at Wayne State University.

2013年，一个由美国海洋化学家和地球化学家组成的多机构小组将对太平洋进行一次大规模考察，以绘制和研究微量元素和同位素的分布，这是国际GEOTRACES计划的一部分。 由于天然U-Th放射性核素系列中的放射性子同位素已被证明作为海洋沉积动力学和流体动力学的天然示踪剂的价值，因此对所有GEOTRACES研究人员来说都具有巨大的价值。 特别是天然存在的Pb 210/Po 210放射性同位素对将可用于量化美国GEOTRACES太平洋活动中其他微量元素和感兴趣的同位素的颗粒清除率。 这是因为这两种同位素本身具有粒子反应性和放射性，因此为跟踪其他粒子反应性物质的垂直传输提供了一个自然时钟。在这个项目中，韦恩州立大学和纽约市立大学皇后学院的研究人员将沿着美国GEOTRACES东南太平洋部分采集和分析数百个溶解和颗粒（大小）样品中的210 Po和210 Pb。大约三分之二的样本将集中在六个所谓的“超级站”（选择进行深入研究的地点），一半在主温跃层之上，另一半在海底霞状层（在海底上方数米处延伸的悬浮物质区）之上。深度将根据区域大气输入，生态系统选择，并与船上其他研究人员的采样协调。另外三分之一将在东太平洋海隆附近的热液羽流中拍摄。数据将根据界面清除模型按颗粒类型（例如细颗粒/胶体颗粒、岩生颗粒和生物颗粒）进行综合。因此，拟议的工作将与其他美国GEOTRACES PI密切协调，在活动期间资助研究其他粒子反应或溶解微量元素和放射性核素同位素。更广泛的影响：更广泛的影响与GEOTRACES计划的整体密切相关： 加强（1）研究基础设施，为海洋地球化学清除模型提供广泛的210 Po和210 Pb数据，（2）通过指导研究生和本科生进行教育，通过拟议研究的例子进行教学，（3）对地球科学事业感兴趣的代表性不足的学生的参与，（4）对海洋放射化学毕业生的研究培训，以及5）通过出版物、演讲以及在韦恩州立大学的专门公共网站上公开传播结果。