Collaborative Research: Circum-Antarctic Processes from Archived Marine Sediment Cores (ANTS)

海底积聚的沉积物提供了关于过去和现在环境变化的丰富信息。在南极洲周围，这些海底沉积物受到冰盖的影响，冰盖将大陆内部的沉积物磨碎并输送到周围的海洋中。自从末次冰盛期（大约2万年前）以来，当冰盖向海延伸数百至数千公里时，冰已经向内陆退缩到我们今天观察到的形状，并在海底沉积物中留下了其增长和下降的特征以及海洋变化的指标。正在进行的冰川和海洋过程反映在当代沉积物的特征中，而海底下较古老的沉积物提供了冰盖和周围海洋变化的较长时间视角。利用主要保存在俄勒冈州立大学南极岩心收集的存档沉积物岩心产生的数据，我们的目标是确认最近的沉积物是否清楚地反映了在南极洲不同地区看到的海洋和冰川变化的具体仪器和历史现场观测。这些现代变化将与数百至数千年前沉积在海底的沉积物所记录的变化联系起来。该项目将探索海底沉积物相互关联的物理、生物和地球化学特性，以解决20世纪和21世纪以及末次盛冰期以来冰川和海洋过程对冰-近端海洋沉积的影响，重点关注沉积物通量、融水排水、浮冰碎屑沉积和放射性碳年代学。我们将整合多代理分析来询问南极洲周围的海底沉积物记录，目标是今天相对快速流动和快速变化的冰川系统的近海区域，以及较慢流动，更稳定（即不变或相对最小变化）的冰盖部分的近海区域。这项工作将利用新技术和知识的应用到遗留沉积物岩心，NSF在收集和存档方面投入了大量资金。该项目由三名早期职业女性项目调查员领导，她们寻求促进合作和开放的研究实践和项目团队的专业成长，项目团队将包括三名研究生，众多本科生和一名博士后研究助理。项目团队将与Math4Science共同制作教材，Math4Science是一个通过课程将STEM专业人员与公立中学学生及其数学和科学教师联系起来的组织；并通过与俄勒冈州立大学海洋和地质储存库以及美国南极计划数据中心的合作，制定和实施处理海洋沉积物核心数据的最佳做法。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Sediments that collect on the seafloor provide a wealth of information about past and present environmental change. Around Antarctica, these seafloor sediments are influenced by an ice sheet that grinds and transports sediments from the continent’s interior into the surrounding ocean. Since the Last Glacial Maximum (about 20,000 years ago) when the ice sheet extended hundreds to thousands of kilometers seaward, ice has retreated inland to the configuration we observe today and left behind signatures of its growth and decline, as well as indicators of ocean change, in the seafloor sediments. Ongoing glacial and ocean processes are reflected in the characteristics of contemporary sediments, whereas older sediments beneath the seafloor offer a longer temporal perspective of changes to the ice sheet and surrounding ocean. Using data generated from archived sediment cores that are predominantly housed in the Antarctic Core Collection at Oregon State University, we aim to confirm if recent sediments clearly reflect the specific instrumental and historical field-based observations of ocean and glacial change seen in different regions of Antarctica. These modern changes will be placed into context with those recorded by sediments deposited on the seafloor hundreds to thousands of years ago.This project will explore interlinked physical, biological, and geochemical properties of seafloor sediments to address the influence of glacial and oceanographic processes on ice-proximal marine sedimentation during the 20th and 21st centuries and since the Last Glacial Maximum, with a focus on sediment fluxes, meltwater drainage, ice-rafted debris deposition, and radiocarbon chronologies. We will integrate multi-proxy analyses to interrogate the seafloor sediment record around Antarctica, targeting regions offshore of relatively fast-flowing and fast-changing glacial systems today and regions offshore of slower flowing, more stable (i.e., unchanging or relatively minimally changing) parts of the ice sheet. This work will leverage the application of new techniques and knowledge to legacy sediment cores that NSF has invested greatly in collecting and archiving. This project is led by three early-career women project investigators who seek to foster collaborative and open research practices and professional growth of the project team which will include three graduate students, numerous undergraduate students, and a postdoctoral research associate. The project team will co-produce educational materials with Math4Science, an organization that connects STEM professionals with public secondary education students and their math and science teachers through curricula; and develop and implement best practices in working with marine sediment core data through a collaboration with the Oregon State University Marine and Geology Repository and the United States Antarctic Program - Data Center.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.