Collaborative Research: US GEOTRACES Pacific Zonal Transect: Rates of supply, removal and internal cycling of trace elements and isotopes

合作研究：美国 GEOTRACES 太平洋地带横断面：微量元素和同位素的供应、去除和内部循环率

• 批准号: 1231211
• 负责人: Willard Moore
• 金额: $ 8.73万
• 依托单位: University South Carolina Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-12-01 至 2016-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1231211&HistoricalAwards=false
• 关键词: Collaborative; Research; US; GEOTRACES; Pacific

The goal of GEOTRACES is to identify processes and quantify fluxes that control the distribution of trace elements and isotopes (TEIs) in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions. While the distribution of numerous TEIs will be mapped by a large team of GEOTRACES PIs along this transect, their distribution cannot be properly interpreted without concurrent measurement of tracers capable of providing rates of internal TEI cycling processes and fluxes at boundaries and across interfaces. Naturally-occurring radioisotopes of the Uranium-Thorium series are well suited for studying the sources and sinks of TEIs on time and space scales necessary to interpret lateral and vertical TEI distributions. In this project, a research team from the Woods Hole Oceanographic Institution and the University of South Carolina at Columbia will carry out measurement of a suite of uranium/thorium series radionuclides on the US GEOTRACES cruise to the Eastern Tropical South Pacific (ETSP) Ocean. This radiotracer suite will include shorter-lived 234Th and 228Th as well as the radium quartet (224Ra, 223Ra, 228Ra, 226Ra), which together allow the quantification of rates of horizontal and vertical transport and mixing, as well as removal at ocean boundaries, surface export, and subsurface remineralization. Broader Impacts: The PIs have actively involved undergraduate and high school students in their prior NSF-funded projects, with two having won awards at ASLO meetings in recent years. The trend will continue with this effort, along with the inclusion of an international guest student who will work on analytical improvements for measuring particulate 228Th. In addition, two WHOI-MIT Joint Program students will be involved using this project as a major part of their PhD theses on Th and Ra isotopes. Contributions to the data management side of the results from these 6 isotopes is eagerly awaited by the modeling community, where there is a lack of multiple thorium isotope data sets on these basin scales for parameterization of the cycling of all particle reactive and biologically active TEIs.

地理位置的目的是识别过程并量化控制痕量元素和同位素（TEI）（TEIS）的分布，并确定这些分布对不断变化的环境条件的敏感性。 虽然沿该样带的一大批地理位置PI绘制了众多TEI的分布，但如果没有同时测量能够提供内部TEI循环过程和边界和跨界面上的磁通速率的示踪剂的示踪剂，则无法正确解释它们的分布。 铀 - thorium系列的自然出现的放射性同位素非常适合研究TEIS的源头和水槽，以解释横向和垂直TEI分布所需的时间和空间尺度。在这个项目中，来自伍兹孔海洋学机构和南卡罗来纳大学哥伦比亚大学的一支研究团队将在美国地理领域的铀/throum系列放射性核素进行测量。 该放射性固定套件将包括寿命较短的第234和228个以及辐射四重奏（224ra，223ra，228ra，226ra），其中允许量化水平和垂直传输和混合速率，以及在海洋边界，表面导出，地下和地下恢复时的删除。更广泛的影响：PIS已积极参与本科生和高中生之前的NSF资助项目，近年来在ASLO会议上获得了两项奖项。趋势将继续进行这项努力，并包括一名国际客座学生，他们将致力于测量颗粒物228的分析改进。此外，两名WHOI-MIT联合计划学生将参与使用该项目作为其TH和RA同位素的博士学位论文的主要部分。建模社区热切期待这6个同位素对数据管理端的贡献，因为这些盆地量表上缺乏多个thor同位素数据集，用于所有粒子反应性和生物活性TEI的循环的参数化。