Collaborative Research: Multi-nuclide approach to systematically evaluate the scatter in surface exposure ages in Antarctica and to develop consistent alpine glacier chronologies

智力优势：pi建议通过结合多核素技术、详细的现场实验、岩石力学研究和气候模拟，研究地球表面过程对宇宙暴露定年在南极洲应用的影响。他们将分析麦克默多干谷内陆地区6套高山冰碛系统的宇宙成因核素清单。该地区非常适合进行这项研究，因为1)目标高山冰碛序列对于帮助重建过去数百万年的温度和降水值至关重要；2)宇宙核素的生产速度通常很高，并且众所周知；3)地表过程的复杂性相对较低。他们的工作有两个具体目标：评估偶发地貌事件在调节极地沙漠表面岩石宇宙成因清单方面的影响，并生成一个高山冰川年表，作为过去几百万年区域气候变化的可靠记录。一个关键目标是制定一种独特的采样策略，通过最大限度地减少混淆宇宙成因核素年表的偶发地貌事件的影响，产生一致的暴露年龄结果。他们将把他们的冰碛年表与马萨诸塞大学阿默斯特分校的合作者开发的区域尺度大气模型联系起来。更广泛的影响：这项研究是跨学科的，包括两位早期的职业科学家。这项工作的成果将用于加强本科教育，并聘请两名女学生参加南极实地和夏季研究项目。扩展服务包括为科尔盖特大学开发虚拟南极实地考察。何东可视化实验室与波士顿大学？南极数字图像分析实验室。pi将继续与洛杉矶谷社区学院（Los Angeles Valley Community College）合作，作为PolarTREC项目的一部分，该学院主要为西班牙裔学生提供服务。该项目将有助于LDEO与Lamont-Doherty中学实地项目中的几所纽约市公立高中之间的合作。

Intellectual Merit: The PIs propose to investigate the impact of earth surface processes on the application of cosmogenic exposure dating in Antarctica by combining multi-nuclide techniques, detailed field experiments, rock-mechanic studies, and climate modeling. They will analyze cosmogenic-nuclide inventories for a suite of six alpine-moraine systems in inland regions of the McMurdo Dry Valleys. This area is ideally suited for this study because 1) the targeted alpine moraine sequences are critically important in helping to reconstruct past temperature and precipitation values over the last several million years, 2) the production rates for cosmogenic nuclides are typically high and well-known, and 3) the complexity of surface processes is relatively low. Their work has two specific goals: to evaluate the effects of episodic geomorphic events in modulating cosmogenic inventories in surface rocks in polar deserts and to generate an alpine glacier chronology that will serve as a robust record of regional climate variation over the last several million years. A key objective is to produce a unique sampling strategy that yields consistent exposure-age results by minimizing the effects of episodic geomorphic events that obfuscate cosmogenic-nuclide chronologies. They will link their moraine chronology with regional-scale atmospheric models developed by collaborators at University of Massachusetts Amherst.Broader impacts: This research is interdisciplinary and includes two early career scientists. Results of this work will be used to enhance undergraduate education by engaging two female students in Antarctic field and summer research projects. Extended outreach includes development of virtual Antarctic field trips for Colgate University?s Ho Tung Visualization Laboratory and Boston University?s Antarctic Digital Image Analyses Laboratory. The PIs will continue to work with the Los Angeles Valley Community College, which serves students of mostly Hispanic origin as part of the PolarTREC program. This project will contribute to the collaboration between LDEO and several New York City public high schools within the Lamont-Doherty Secondary School Field Program.