Collaborative Research: US GEOTRACES North Atlantic Section - Nd isotope distribution: sources, sinks and internal cycling

美国GEOTRACES项目是一个新启动的国际海洋学项目，其目标是确定控制海洋中关键微量元素和同位素分布的过程和量化通量，并建立对这些分布对不断变化的环境条件的敏感性的理解。钕（Nd）是一种稀土元素，通过大陆风化作用提供给海洋，其同位素已被确定为重要的海洋示踪剂，可以潜在地提高我们对水团路径的理解，以及确定现代和过去海洋中微量元素的来源和汇。来自哥伦比亚大学、南卡罗来纳大学和夏威夷大学的科学家们将对2010年GEOTRACES北大西洋纬向剖面的溶解海水Nd同位素分布和浓度进行严格的调查。本研究的结果将确定在边缘和开放海洋环境中Nd同位素跟踪平流水团的效果，估计海底地下水排放对Nd的贡献，并确定大气Nd输入和海洋沉积物的通量。这项研究将有助于科学家在全球范围内确定Nd同位素的海洋分布。这项研究的教育影响包括对研究生和博士后学生的支持，以及对本科生的培训机会。

The objective of the US GEOTRACES program, a newly initiated international oceanographic program, is to identify processes and quantify fluxes that control the distributions of key trace elements and isotopes in the oceans and to establish an understanding of the sensitivity of these distributions to changing environmental conditions. Neodymium (Nd), a rare earth element, is supplied to the ocean via continental weathering, and its isotopes have been identified as an important ocean tracer that could potentially improve our understanding of water mass pathways, as well as identify sources and sinks of trace elements in modern and past oceans. Scientists from Columbia University, the University of South Carolina, and the University of Hawaii will be conducting a rigorous survey of the distribution of dissolved seawater Nd isotopes and concentrations along the 2010 GEOTRACES North Atlantic zonal section. Results from this study will determine how well Nd isotopes track advected water masses in marginal and open ocean settings, estimate the Nd contribution from submarine groundwater discharge, and determine atmospheric Nd input and fluxes into and out of marine sediments. This research will aid scientists in determining the oceanic distribution of Nd isotopes on a global scale. The educational impacts of this research include support for a graduate and postdoctoral student, as well as training opportunities for an undergraduate student.