Constraining the Deglaciation of the Antarctic Peninsula Using OSL Dated Beach Deposits

主要研究者/机构：Simms，亚历山大（俄克拉荷马州; alex. okstate.edu）提案编号：0838781职务：使用OSL日期的海滩沉积物限制南极半岛的冰川消退该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。本项目的目的是从南极半岛五个地区的高起海滩脊和卵石路面中的整个卵石中获取光释光（OSL）测年数据。由于南极半岛沿海沉积物的有机碳含量较低，研究人员建议使用光释光测年法来测定指示海平面变化的特征。PI表明，OSL测量是可能的，特别是鹅卵石内提出的海滩山脊和巨石路面和初步OSL年龄从海滩山脊在南设得兰群岛显示与现有的海平面校正放射性碳衍生的海平面曲线的协议。PI假设，在整个南极半岛，从北到南和从东到西可以看到海平面历史的系统性差异。海滩脊和卵石铺路石的古年龄，沿着与均衡模拟，提供了重要的限制厚度和退缩历史的南极半岛冰盖自末次盛冰期。冰盖的精确重建对于试图将均衡调整与卫星重力测量结果（表明该地区正在融化）分离开来的研究人员来说非常重要，因此可以根据海平面上升和全球变暖的预测来帮助预测冰盖的未来命运。这一提议的更广泛影响是，这些数据可能有助于限制对未来冰盖对全球变暖的反应的预测。这两个PI都来自EPScOR州立机构，该机构有一个新的地质学博士课程。该机构向美国土著学生授予第二多的学士学位，增加了与这项工作相关的本科生来自代表性不足的群体的机会。从这项研究中发展出来的讲座将在俄克拉荷马州内三所不授予地质学学位的小型大学进行。该补助金包括对两名研究生的资助。

Lead PI/Institution: Simms, Alexander (Oklahoma State; alex.simms@okstate.edu)Proposal Number: 0838781Title: Constraining the Deglaciation of the Antarctic Peninsula Using OSL Dated Beach DepositsThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The purpose of this proposal is to acquire Optically Stimulated Luminescence (OSL) dates from whole cobbles within raised beach ridges and boulder pavements from five areas in the Antarctic Peninsula. The PIs propose to use OSL to date features indicative of sea level variations that are not accessible with radiocarbon methods because of low organic carbon contents of coastal sediments from the Antarctic Peninsula. The PIs suggest that OSL measurements are possible in particular cobbles within raised beach ridges and boulder pavements and preliminary OSL ages from beach ridges in the South Shetland Islands show agreement with existing reservoir-corrected radiocarbon-derived sea-level curves. The PIs hypothesize that systematic differences in sea level histories can be seen from north to south and east to west across the Antarctic Peninsula. Paleo-ages of beach ridges and boulder pavements could, along with isostatic modeling, provide important constraints on the thickness and retreat history of the Antarctic Peninsula Ice Sheet since the Last Glacial Maximum. Accurate reconstructions of the ice sheet are important for researchers attempting to disentangle the isostatic adjustment from satellite gravity measurements that suggest melting in the region, and thus could help predict the future fate of ice sheets in light of predictions of sea-level rise and global warming. The broader impacts of this proposal are that these data could help constrain the prediction of future ice-sheet responses to global warming. Both PIs are from an EPScOR state institution that has a new PhD program in Geology. This institution awards the second-most number of BS degrees to Native American students in the country increasing the chance that undergraduate students associated with this work are from under represented groups. Lectures developed from this research will be given at three smaller universities within the state of Oklahoma that do not grant degrees in geology. The grant includes support for two graduate students.