摘要
For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and common mid-point surveys we analyze the radar velocities in ice with respect to cold-temperate ice transi- tion surface （0.1751 0.0028 m ns-~） and ice-bedrock interface （0.1657 ＋ 0.0033 m ns-a）, indicating a radar velocity of 0.1410 4- 0.0154 m ns-1 for the temperate ice layer （16.6 ~ 1.8 m）. We estimate that the temperate ice layer has a water content of around 6 % 4- 4 %, suggesting that the Jima Yangzong Glacier, previously known as continental-type, now possibly becomes polythermal.
For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and common mid-point surveys we analyze the radar velocities in ice with respect to cold-temperate ice transition surface(0.1751 ± 0.0028 m ns^(-1)) and ice-bedrock interface(0.1657 ± 0.0033 m ns^(-1)), indicating a radar velocity of 0.1410 ± 0.0154 m ns^(-1) for the temperate ice layer(16.6 ± 1.8 m). We estimate that the temperate ice layer has a water content of around 6 % ± 4 %, suggesting that the Jima Yangzong Glacier, previously known as continental-type, now possibly becomes polythermal.
基金
supported by the Polar Atmospheric Science Field Base of CAMS(2016Z005)
National Natural Science Foundation of China(41425003)
National Fundamental Research Project(973)of China(2007CB411503)
