摘要
We use multi-frequency ground penetrating radar （GPR） to detect and map debris thickness and shallow layer structure of buried ice-body under debris-covered. The basis analysis is depend on mainly （1） the stacking wave velocity in a common mid-point （CMP） survey, （2） the ratio of attenuation of an electromagnetic wave passing through different media, and （3） the vertical resolu- tion. Through a series of analysis, it was found that the optimal average velocity in the shallow layer （0-4 m） is 0.06 m/ns. Images obtained with antennas having different frequencies have different char- acteristics; i.e., the 50 MHz antenna provides much worse vertical resolution than the 200 and 100 MHz antennas （90 and 160 ns, respectively） and the performance of the 200 MHz antenna for a debris-covered glacier is best. This study provides the basis for accurate analysis of the structure and thickness of the debris layer in the zone of ablation of a debris-covered glacier, this study also provides a reference for research into the formation mechanism and estimation of the ice volume of glacier covered by debris.
We use multi-frequency ground penetrating radar （GPR） to detect and map debris thickness and shallow layer structure of buried ice-body under debris-covered. The basis analysis is depend on mainly （1） the stacking wave velocity in a common mid-point （CMP） survey, （2） the ratio of attenuation of an electromagnetic wave passing through different media, and （3） the vertical resolu- tion. Through a series of analysis, it was found that the optimal average velocity in the shallow layer （0-4 m） is 0.06 m/ns. Images obtained with antennas having different frequencies have different char- acteristics; i.e., the 50 MHz antenna provides much worse vertical resolution than the 200 and 100 MHz antennas （90 and 160 ns, respectively） and the performance of the 200 MHz antenna for a debris-covered glacier is best. This study provides the basis for accurate analysis of the structure and thickness of the debris layer in the zone of ablation of a debris-covered glacier, this study also provides a reference for research into the formation mechanism and estimation of the ice volume of glacier covered by debris.
基金
supported by the Chinese Glacier Inventory(Nos.2008DFA20400 and 2012M521817)
