气候变化领域集成服务门户(CCPortal): Internal structure of two alpine rock glaciers investigated by quasi-3-D electrical resistivity imaging

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DOI	10.5194/tc-11-841-2017
	Internal structure of two alpine rock glaciers investigated by quasi-3-D electrical resistivity imaging
	Emmert A.; Kneisel C.
发表日期	2017
ISSN	19940416
卷号	11 期号:2
英文摘要	Interactions between different formative processes are reflected in the internal structure of rock glaciers. Therefore, the detection of subsurface conditions can help to enhance our understanding of landform development. For an assessment of subsurface conditions, we present an analysis of the spatial variability of active layer thickness, ground ice content and frost table topography for two different rock glaciers in the Eastern Swiss Alps by means of quasi-3-D electrical resistivity imaging (ERI). This approach enables an extensive mapping of subsurface structures and a spatial overlay between site-specific surface and subsurface characteristics. At Nair rock glacier, we discovered a gradual descent of the frost table in a downslope direction and a constant decrease of ice content which follows the observed surface topography. This is attributed to ice formation by refreezing meltwater from an embedded snow bank or from a subsurface ice patch which reshapes the permafrost layer. The heterogeneous ground ice distribution at Uertsch rock glacier indicates that multiple processes on different time domains were involved in the development. Resistivity values which represent frozen conditions vary within a wide range and indicate a successive formation which includes several advances, past glacial overrides and creep processes on the rock glacier surface. In combination with the observed topography, quasi-3-D ERI enables us to delimit areas of extensive and compressive flow in close proximity. Excellent data quality was provided by a good coupling of electrodes to the ground in the pebbly material of the investigated rock glaciers. Results show the value of the quasi-3-D ERI approach but advise the application of complementary geophysical methods for interpreting the results. © 2017 The Author(s).
学科领域	active layer; data quality; electrical resistivity; landform; meltwater; permafrost; rock glacier; topography; valley glacier
语种	英语
scopus关键词	active layer; data quality; electrical resistivity; landform; meltwater; permafrost; rock glacier; topography; valley glacier
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119419
作者单位	Institute of Geography and Geology, University of Würzburg, Würzburg, 97074, Germany
推荐引用方式 GB/T 7714	Emmert A.,Kneisel C.. Internal structure of two alpine rock glaciers investigated by quasi-3-D electrical resistivity imaging[J],2017,11(2).
APA	Emmert A.,&Kneisel C..(2017).Internal structure of two alpine rock glaciers investigated by quasi-3-D electrical resistivity imaging.Cryosphere,11(2).
MLA	Emmert A.,et al."Internal structure of two alpine rock glaciers investigated by quasi-3-D electrical resistivity imaging".Cryosphere 11.2(2017).