Collaborative Research: Multidisciplinary Analysis of Antarctic Blue Ice Moraine Formation and their Potential as Climate Archives over Multiple Glacial Cycles

合作研究：南极蓝冰碛形成及其作为多个冰川周期气候档案的潜力的多学科分析

基本信息

批准号：
1443433
负责人：
Kathy Licht
金额：
$ 25.17万
依托单位：
Indiana University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2015
资助国家：
美国
起止时间：
2015-09-01 至 2020-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1443433&HistoricalAwards=false
关键词：
Collaborative Research Multidisciplinary Analysis Antarctic

项目摘要

Licht/1443433Sediments deposited by the Antarctic ice sheet are an archive of its history with time and help geologists to determine how the remote interior of the ice sheet has changed over the past several hundred thousand years. This project will focus on the formation and dynamics of moraines (accumulations of dirt and rocks that are incorporated in the glacier surface or have been pushed along by the glacier as it moves) near the blue ice area of Mt. Achernar in the central Transantarctic Mountains in Antarctica.. The study will improve basic understanding of the formation of these moraines. Fieldwork at the site will focus on imaging the internal structure of the moraine to determine the processes by which it, and others like it, form over time. Additional analyses will include measurements of ice flow and collection of rock samples to determine the timing of debris deposition and the changes in the sources of sediments from deep within the Antarctic continent. The project will provide both graduate and undergraduate students training in paleoclimate studies, geology, and numerical modeling approaches. The broader impacts of the proposed work include hands on training in the Earth Sciences for graduate and undergraduate students, collaboration with colleagues in New Zealand and Sweden to provide an international research experience for students from the US, and three educational modules to be delivered by student researchers regarding Antarctica's role in global environments. The research is societally relevant and multidisciplinary and the topics are ideal for sharing with the public. All research findings will be made publicly available to others via timely publication in high-impact, peer-reviewed journals and all data will be submitted to the National Snow and Ice Data Center, and excess samples will be provided to the U.S. Polar Rock Repository.Direct observations of ice sheet history from the margins of Antarctica's polar plateau are essential for testing numerical ice sheet models, and the laterally extensive, blue-ice moraines of the Mt. Achernar Moraine complex in the central Transantarctic Mountains contain a unique and nearly untapped direct, quasi-continuous record of ice sheet change over multiple glacial cycles. The project objectives include improved understanding of processes and rates of blue ice moraine formation, as well as identifying the topographic, glaciological, and climatic controls on their evolution. Data to be collected with fieldwork in Antarctica include: imaging of internal ice structure with ground-penetrating radar, measurement of ice flow velocity and direction with a global positioning system (GPS) array, analysis of debris concentration and composition in glacier ice, state-of-the-art cosmogenic multi-nuclide analyses to determine exposure ages of moraine debris, mapping of trimlines and provenance analysis. Numerical model simulations, constrained by field data, will be used to evaluate the factors influencing changes in glacier flow that potentially impact the accumulation of the moraine debris. All together, the new data and modeling efforts will improve conceptual models of blue ice moraine formation, and thereby make them a more valuable proxy for developing a better understanding of the history of the ice sheet.

Licht/1443433南极冰盖沉积的沉积物是其历史的档案，可帮助地质学家确定冰盖遥远的内部在过去数十万年中如何变化。该项目将重点研究横贯南极山脉中部阿赫纳尔山蓝色冰区附近冰碛的形成和动态（冰川表面融入的泥土和岩石或在冰川移动时被冰川推动的泥土和岩石的堆积）在南极洲......这项研究将增进对这些冰碛形成的基本了解。现场的实地工作将重点对冰碛的内部结构进行成像，以确定它和其他类似冰碛随着时间的推移形成的过程。其他分析将包括测量冰流和收集岩石样本，以确定碎片沉积的时间以及南极大陆深处沉积物来源的变化。该项目将为研究生和本科生提供古气候研究、地质学和数值模拟方法方面的培训。拟议工作的更广泛影响包括为研究生和本科生提供地球科学实践培训、与新西兰和瑞典的同事合作为美国学生提供国际研究经验，以及由学生提供的三个教育模块研究人员了解南极洲在全球环境中的作用。该研究具有社会相关性和跨学科性，其主题非常适合与公众分享。所有研究结果将通过在高影响力、同行评审的期刊上及时发表来向其他人公开，所有数据将提交给国家冰雪数据中心，多余的样本将提供给美国极地岩石存储库。从南极洲极地高原边缘直接观测冰盖历史对于测试数值冰盖模型以及中部阿赫纳尔冰碛复合体的横向广泛的蓝色冰碛至关重要横贯南极山脉拥有独特且几乎尚未开发的直接、准连续的多个冰川周期冰盖变化记录。该项目的目标包括提高对蓝冰碛形成过程和速率的了解，以及确定对其演化的地形、冰川和气候控制。南极洲实地工作收集的数据包括：利用探地雷达对内部冰结构进行成像、利用全球定位系统（GPS）阵列测量冰流速度和方向、分析冰川冰中的碎片浓度和成分、状态-最先进的宇宙成因多核素分析，以确定冰碛碎片的暴露年龄，绘制边线和来源分析。受现场数据约束的数值模型模拟将用于评估影响冰川流量变化的因素，这些变化可能会影响冰碛碎片的积累。总之，新的数据和建模工作将改进蓝冰碛形成的概念模型，从而使它们成为更有价值的代理，以更好地了解冰盖的历史。

项目成果

期刊论文数量（4）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Warm-based basal sediment entrainment and far-field Pleistocene origin evidenced in central Transantarctic blue ice through stable isotopes and internal structures

通过稳定同位素和内部结构在跨南极蓝冰中部证实了暖基基底沉积物夹带和远场更新世起源

DOI：
10.1017/jog.2018.4
发表时间：
2018-03
期刊：
Journal of Glaciology
影响因子：
3.4
作者：
GRALY, JOSEPH A.;LICHT, KATHY J.;KASSAB, CHRISTINE M.;BIRD, BROXTON W.;KAPLAN, MICHAEL R.
通讯作者：
KAPLAN, MICHAEL R.

Chemical weathering signatures from Mt. Achernar Moraine, Central Transantarctic Mountains I: Subglacial sediments compared with underlying rock

跨南极山脉中部阿赫纳尔冰碛山的化学风化特征 I：冰下沉积物与下伏岩石的比较