Collaborative Research: Reorganization of deepwater circulation in response to the opening of Southern Ocean passages in the middle/late Eocene (40-33 Ma)

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该奖项支持对始新世南大洋通道开放的深水环流响应的研究。PIs将生成多个大洋盆地始新世中晚期底栖有孔虫稳定同位素数据，以验证以下假设：(1)内部分层的新生代海洋结构开始于~40 Ma，以响应相对于北部成分水密度的增加；(2)盆地间氧同位素梯度在始新世晚期随着南部海洋门户逐渐加深而逐渐增加。使原南极绕极洋流得以发展和加强。所产生的数据将阐明海洋环流变化与碳酸盐补偿深度所反映的海洋碳循环变化之间的关系，以及发展一个更明确的海洋内部结构和相关的营养物分布，作为这些变化的强迫机制。更广泛的影响包括博士研究生的教育和培训，本科生参与实验室研究，以及通过客座讲座和课程开发向当地高中推广。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This awards supports an investigation of the deepwater circulation response to the opening of the Southern Ocean passages in the Eocene. The PIs will generate benthic foraminiferal stable isotope data from the middle-late Eocene in multiple ocean basins to test the hypotheses that (1) the internally stratified Cenozoic ocean structure began ~40 Ma in response to increasing dense southern component water relative to northern component water, and (2) interbasinal oxygen isotope gradients gradually increased through the late Eocene as southern ocean gateways progressively deepened, allowing the proto-Antarctic Circumpolar current to develop and strengthen. The data generated will shed light on the relationship between ocean circulation changes and the alteration of the marine carbon cycle as reflected in the carbonate compensation depth, and on the development of a better defined internal ocean structure and associated nutrient distribution as a forcing mechanism for these changes. Broader impacts include education and training of a PhD student, involvement of undergraduates in laboratory research, and outreach to local high schools via guest lectures and curriculum development.