Rates of Glacial Erosion in Southern Alaska

这项研究涉及一个具有广泛科学兴趣的突出问题：构造活跃地区的冰川侵蚀速率，以及它对构造、气候和侵蚀相互作用所决定的山脉发展的影响。拟议研究的白令海峡冰川部分也有望提供有关沉积物的快速冰川覆盖及其对冰川动力学和冰川崩解稳定性的影响的有价值的新信息。目标是：通过监测前冰期维特斯湖的沉积物堆积，确定白令海峡冰川排水的广阔（5000平方公里）和构造活跃地区的当前侵蚀率，包括海平面高度极高的圣埃利亚斯山地区。研究人员最近在阿拉斯加东南部的峡湾和内陆通道获得的大量新数据。这些数据有望提供有关第四纪和全新世沉积物产量的宝贵信息，这些信息可以与已知的较高的长期区域发掘率进行比较。收集来自阿拉斯加东南部其他冰川的现成数据，以改善对控制冰川侵蚀和沉积物向峡湾转移的区域速率的因素的定义和理解。通过地壳汇聚的连续力学模型，结合冰川侵蚀和沉积物转移的简单抽象，开发一个定量框架，以探索快速冰川侵蚀和沉积物转移的地形和地球动力学含义。多方面的研究被认为是可行的，在项目拟议的五年期限内：这是一项由四名成熟的研究人员参与的小组努力，并以现有的大量数据为基础。研究人员包括美国陆军寒区研究与工程实验室的卢·亨特、独立资助的美国地质勘测局研究人员布鲁斯·莫尼亚和保罗·卡尔森，以及首席研究员伯纳德·哈莱特和研究助理扬·梅兰德（两人都在华盛顿大学）。所有成员都将参加实地工作。我们团队的集体专业知识非常适合拟议的工作；它来自于在峡湾和沿海水域以及阿拉斯加冰川上的大量实地经验，以及对冰川侵蚀和崩解边缘过程、过程地貌学和地球动力学的定量研究。我们强调，与美国地质勘探局和CRREL的合作将有力地利用本文所要求的国家科学基金会资源。Molnia和Carlson以及支持地震工作的电子技术人员的工资由美国地质勘探局支付。美国地质勘探局的其他贡献包括查阅过去的摄影、地震和其他记录；装备精良的大本营；和志愿者的帮助，包括本科生，由Merit有限公司赞助，亨特的薪水不仅使我们能够利用他的专业知识，使他成为我们研究团队的积极成员，而且还使我们能够利用包括丹尼尔·劳森在内的CRREL的其他专业知识，使用CRREL的编辑，图形/摄影设施，并借用一些现场设备。

Hallet 9628675 The research bears on an outstanding issue of broad scientific interest: the rate of glacial erosion in a tectonically active area, and its implications for the development of mountain ranges as dictated by the interplay of tectonics, climate, and erosion. The Bering Glacier section of the proposed study also promises to yield valuable new information on rapid glacial over-riding of sediments and its implication regarding the dynamics of glaciers and the stability of calving glaciers. Objectives are: to determine current erosion rates in the extensive (5000 km2) and tectonically active region drained by Bering Glacier, including the Mt. St. Elias area with unsurpassed relief from sea level, by monitoring sediment accumulation in the proglacial Vitus Lake complex. to examine considerable new data recently obtained by ACCRETE researchers in the fjords and inland passages of SE Alaska. These data promise to yield valuable information about Quaternary and Holocene sediment yields over a broad, heavily glacierized area that can be compared to longer term regional exhumation rates known to be high. to compile readily available data from other SE Alaska glaciers to improve the definition and understanding of factors controlling regional rates of glacial erosion and sediment transfer to fjords. to develop a quantitative framework for exploring the topographic and geodynamic implications of rapid glacial erosion and sediment transfer through a continuum mechanical model of crustal convergence coupled with a simple abstraction of erosion and sediment transfer by glaciers. The multifaceted research is deemed feasible, within the five-year proposed duration of the project: it is a group effort involving four established researchers and is founded on considerable data already available. It involves Lew Hunter of the U.S. Army Cold Regions Research and Engineering Laboratory, and independently funded USGS researchers, Bruce Molnia and Paul Carslon, as well as principal inves tigator Bernard Hallet and research assistant Yann Merrand (both at the University of Washington). All members will participate in field work. The collective expertise of our team is ideally suited for the proposed work; it emanates from considerable field experience in fjords and coastal waters and on glaciers in Alaska, and from quantitative studies of glacial erosion and calving-margin processes, process geomorphology and geodynamics. We stress that the NSF resources requested herein will strongly leveraged by the collaboration with the USGS and CRREL. Salaries for Molnia and Carlson, and for an electronics technician to support the seismic work, are covered by the USGS. Other USGS contributions include access to past photographic, seismic, and other records; a well equipped base camp; and assistance from volunteers, including undergraduate students, sponsored by the Merit Corp. Limited salary for Hunter permits us not only to draw on his expertise and to include him as an active member of our research team, but also enables us to tap additional expertise at CRREL including Daniel Lawson, to use CRREL editorial, graphics/photography facilities, and to borrow some field equipment.