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：摘要本研究旨在对北大西洋深水输出通量变化特别敏感的南大西洋全新世和末次冰期极大期（LGM） epsilon-钕（Nd）同位素的分布进行大规模调查。先前使用底栖有孔虫的碳同位素生成水质量几何形状的样品。该项目将评估覆盖南大西洋不同水深和位置的岩心的epsilon-Nd同位素，以开发LGM和全新世的时间切片图。这些数据将在很大程度上补充现有碳同位素数据数据库。此外，PI计划收集一份过去30天的长期变化记录，这些记录来自南美洲东海岸的西阿拉隆起的一个地核。所有的数据将来自自生氧化锰铁沉淀。所产生的数据将为冰川时代海洋环流的重建以及晚第四纪epsilon-Nd和底栖碳同位素记录的关联解释提供改进的基础。更广泛的影响这个项目的更广泛的影响是强大的。该项目将支持一位有前途的早期职业女性科学家，并为该研究的一名本科生提供资金。资深科学家的指导以及初级科学家对本科生的指导和指导是博士后培养的重要内容。

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.