Earth Sciences Postdoctoral Research Fellowship Award

古海洋学中一个悬而未决的争议是温暖的咸水底水(WSBW)的作用，据推测，WSBW形成于低纬度的受限边缘盆地，现在发生在深水循环中。稳定的氧和碳同位素数据表明，过去WSBW可能曾多次主导海洋环流，但陈旧的同位素特征并不是唯一的水团示踪剂。由于ND在海洋中的停留时间短，不同水团的ND同位素输入值不同，该体系可能是一种保守的水团示踪剂。鱼牙磷灰石可能通过Nd同位素提供深水记录。这项研究将有助于评估鱼牙磷灰石吸收稀土元素(REE)的时机和机制两个不同岩性控制的深海样品对成岩蚀变的影响。这也应该使我们能够确定跨越古新世/始新世界线的鱼牙成分，这是提出的WSBS形成的时间。过去海洋环流模式的重大变化将影响营养物质的分布和氧化还原条件，以及直接影响全球气候的热量传递和大气气体的气/海交换。

An unresolved controversy in paleoceanography is the role of warm, saline bottom water (WSBW), presumably formed at low latitudes in restricted marginal basins, now occurring in deep water circulation. Stable oxygen and carbon isotope data suggest WSBW may have dominated ocean circulation at several times in the past, but stale isotope signatures are not unique water mass tracers. Due to the short oceanic residence time of Nd and the distinct Nd isotope input values to different water masses, this Nd isotopic system may be a conservative tracer of water mass. Fish tooth apatite may provide a deep water record through Nd isotopes. This study should aid in evaluating the timing and mechanism of the rare earth element (REE) uptake in fish tooth apatite by examining samples from two deep sea sites with different lithologic controls on diagenetic alteration. It should also allow us to determine fish tooth composition across the Paleocene/Eocene boundary, a time of proposed WSBS formation. Major changes in the mode of ocean circulation in the past would impact nutrient distributions and redox conditions, as well as the transfer of heat and air/sea exchange of atmospheric gases that directly influence global climate.