High Resolution Radar Profiling of Firn Stratigraphy in East Antarctia: The ITASE II Traverse from Victoria Land to South Pole Station

南极洲东部弗恩地层的高分辨率雷达剖面图：ITASE II 从维多利亚陆地到南极站的穿越

• 批准号: 0440533
• 负责人: Steven Arcone
• 金额: $ 17.88万
• 依托单位: Department of Army Cold Regions Research & Engineering Lab
• 依托单位国家: 美国
• 项目类别: Interagency Agreement
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0440533&HistoricalAwards=false
• 关键词: Resolution; Radar; Profiling; Firn; Stratigraphy

This award supports the acquisition of high resolution ground-penetrating radar (GPR) profiles as part of the ITASE-2 traverse, along a route in East Antarctica from Victoria Land to South Pole Station. The project will collect profiles of the firn stratigraphy to aid in the selection of coring sites, measure spatially averaged snow accumulation rates and determine the ice dynamics that cause the stratigraphy. The radar profiles from the GPR work will be correlated with ice core stratigraphy and GPS data obtained by others as part of the traverse. GPR will also be used for crevasse detection and traverse route safety but this is considered routine, based on experience from prior work.. The major GPR findings in stratigraphic dynamics from ITASE I are: 1) most 400-MHz horizons are separate and distinct wavelets that extend over 500 km; 2) horizons appear to be caused by the density contrasts across clusters of thin, double-layers of hoar and ice; and 3) the folding can be caused by differential accumulation processes and the interaction between differential wavelength and ice speed, all tempered by radar velocity pulldown. effects. This proposal is based on the hypothesis that the same processes that generate and fold reflection horizons in the relatively greater and warmer accumulation zone of West Antarctica, are also at work in the relatively lesser and far colder accumulation zone of East Antarctica, and will be detected despite the fact that the accumulation rates, in cm of firn at any density, are far less than the vertical resolution of the radar. The major objectives of this project are to test this hypothesis by searching for thin layer signatures, and evidence of folding caused by differential accumulation dynamics. Evidence will also be sought of tectonic folding, most likely caused by convergence within feeder areas for the glaciers of the Transantarctic Mountains, and of the small scale continuity of horizons. For each of the two field years, the funding will also support a student for 4 months, minor equipment purchases, travel, editing, publications and supplies. The student will be a temporary employee of USA CRREL to support him or her during the summer months.

该奖项支持从维多利亚州到南极站东部的一条路线，沿着南极洲东部的一条路线沿着ITASE-2 Traverse的一部分收购了高分辨率地面渗透雷达（GPR）概况。 该项目将收集FIRN地层学的概况，以帮助选择取芯部位，测量空间平均的积雪速率并确定导致地层学的冰动力学。 GPR工作的雷达谱将与其他人作为Traverse的一部分获得的冰核地层和GPS数据相关。 GPR还将用于裂缝检测和横路路线安全性，但根据先前工作的经验，这被认为是常规的。.1）大多数400-MHz的地平线是分离的，大多数400-MHz的视线是延伸超过500 km的独立且独特的小波； 2）地平线似乎是由较薄的双层和冰的薄层之间的密度对比引起的； 3）折叠可能是由差分累积过程以及差异波长和冰速之间的相互作用引起的，所有这些都由雷达速度下拉而降低。效果。 该提议基于以下假设：在南极西部相对更大，更温暖的积累区中产生和折叠反射范围的相同过程在相对较小，南极洲东部的较冷的积累区中也在起作用，并且将被检测到，尽管在任何密度的cm cm cm of firn中，但垂直方向都远不及以下事实。 该项目的主要目标是通过寻找薄层特征来检验这一假设，以及由不同的积累动态引起的折叠证据。 还将寻求证据表明构造折叠，这很可能是由于跨急诊山脉冰川和地平线的小规模连续性在馈线区域内的收敛引起的。在这两个野外年中的每一个中，资金还将为学生提供4个月的支持，次要的设备购买，旅行，编辑，出版物和用品。 该学生将是美国CRREL的临时雇员，以在夏季支持他或她。