CAREER: Tracing Antarctic Sediment Transport Pathways and Antarctic Ice Sheet Stability Using Iron-titanium Oxide Magnetic and Chemical fingerprints

职业：利用铁钛氧化物磁性和化学指纹追踪南极沉积物输送路径和南极冰盖稳定性

• 批准号: 0348274
• 负责人: Stefanie Brachfeld
• 金额: $ 40.03万
• 依托单位: Montclair State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-01 至 2011-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0348274&HistoricalAwards=false
• 关键词: CAREER; Tracing; Antarctic; Sediment; Transport

This project will develop a suite of tracers to understand sediment transport in the Antarctic margin. These sediments are glacially derived and understanding their origin will provide insight into the controls on the stability of the Antarctic Ice Sheet. The method exploits the distinctive elemental fingerprints in iron-titanium oxides to characterize source regions. Iron titanium oxides contain an array of major, minor and trace elements. These elemental profiles will be quantified via electron microprobe and used to define a geochemical fingerprint for each source area. Unknown samples will be traced to their sources using discriminant function analysis. The ability to trace Antarctic glacial marine sediment deposited along the continental margin and in the Southern Ocean will provide a means of tracking advances and retreats of the West Antarctic Ice Sheet, East Antarctic Ice Sheet, and the Antarctic Peninsula glaciers and ice shelves. Source area fingerprints will be derived from existing circum-Antarctic samples of glacial till and ice-proximal sand. These samples will also be studied to determine their magnetic parameters, sediment geochemistry, and radioisotope signatures to track their dispersal through the world's oceans. This project involves substantial undergraduate and graduate student training in mineralogy, petrology, sedimentology, geochemistry, microscopy, magnetism and statistics. Montclair State University has a diverse student body that will permit the PI to work towards recruitment and retention of women in science. Students will also work at a diverse array of state of the art research facilities including the Antarctic Research Facility, the Polar Rock Repository, the Institute for Rock Magnetism, Lamont Doherty Earth Observatory, and core repositories of the Ocean Drilling Program. Major themes of this project will be crafted into Antarctic and global change lessons for elementary school teachers.

该项目将开发一套示踪剂来了解南极边缘的沉积物运输。这些沉积物是冰川形成的，了解它们的起源将有助于深入了解对南极冰盖稳定性的控制。该方法利用铁钛氧化物中独特的元素指纹来表征源区。铁钛氧化物含有一系列主要元素、次要元素和微量元素。这些元素分布将通过电子微探针进行量化，并用于定义每个源区域的地球化学指纹。将使用判别函数分析来追踪未知样本的来源。追踪沿大陆边缘和南大洋沉积的南极冰川海洋沉积物的能力将为追踪南极西部冰盖、南极东部冰盖以及南极半岛冰川和冰架的前进和后退提供一种手段。源区指纹将从现有的环南极冰碛物和近冰沙样本中获得。还将研究这些样本，以确定它们的磁性参数、沉积物地球化学和放射性同位素特征，以追踪它们在世界海洋中的扩散。该项目涉及矿物学、岩石学、沉积学、地球化学、显微镜、磁学和统计学方面的大量本科生和研究生培训。蒙特克莱尔州立大学拥有多元化的学生群体，这将使 PI 能够致力于招募和留住科学界的女性。学生还将在各种最先进的研究设施中工作，包括南极研究设施、极地岩石储存库、岩石磁学研究所、拉蒙特·多尔蒂地球观测站和海洋钻探计划的核心储存库。该项目的主要主题将被纳入小学教师的南极和全球变化课程中。