Glacial water mass geometry in the South Atlantic: testing neodymium isotopes versus benthic carbon isotopes as paleo-water mass tracers

南大西洋冰川水团的几何形状：测试钕同位素与海底碳同位素作为古水体示踪剂KatharinaPahnkeLamontDoherty地球观测台摘要所提出的研究旨在对南大西洋的ε-钕（Nd）同位素的全新世和末次盛冰期（LGM）分布进行大规模调查，该地区对北大西洋深水输出通量的变化特别敏感，对以前使用的样本进行了分析，以利用底栖有孔虫中的碳同位素生成水团几何形状。该项目将评估覆盖南大西洋各种水深和地点的岩芯中的ε-Nd同位素，以绘制末次盛冰期和全新世的时间片图。这些数据将在很大程度上补充现有的碳同位素数据库。此外，PI计划从沿着南美洲东海岸的塞阿拉海隆的岩芯收集过去~30千公里的长期变化记录。所有的数据将来自自生铁锰氧化物沉淀。所产生的数据将提供一个更好的基础，重建冰川时代的海洋环流和晚第四纪epsilon-Nd和海底碳同位素记录的相关解释。该项目将支持一位有前途的早期职业女性科学家，并为一名本科生提供研究资金。资深科学家的指导以及初级科学家监督和指导本科生的机会在博士后培训中被认为是重要的。

Glacial water mass geometry in the South Atlantic: testing neodymium isotopes versus benthic carbon isotopes as paleo-water mass tracersKatharina PahnkeLamont Doherty Earth ObservatoryAbstractThe proposed study is designed to conduct a large-scale survey of the Holocene and Last Glacial Maximum (LGM) distribution of epsilon-Neodymium (Nd) isotopes in the South Atlantic, an area particularly sensitive to changes in the export flux of North Atlantic Deep Water, on samples used previously to generate the water mass geometry using carbon isotopes in benthic foraminifera. The project will evaluate epsilon-Nd isotopes from cores that cover a range of water depths and locations in the South Atlantic in order to develop time slice maps for the LGM and Holocene. These data will largely complement an existing database of carbon isotope data. In addition, the PI plans to put together a record of secular variations for the past ~30 ky from a core on the Ceara Rise, along the east coast of South America. All of the data will be derived from authigenic ferromanganese oxide precipitate. The data produced will provide an improved basis for the reconstruction of glacial age ocean circulation and for the linked interpretation of Late Quaternary epsilon-Nd and benthic carbon isotope records.Broader ImpactsThe broader impacts of this project are strong. The project will support a promising early-career woman scientist and includes funds for an undergraduate in the research. The mentoring by senior scientists as well the opportunity for the junior scientist to supervise and mentor an undergraduate are recognized as important in postdoctoral training.