Vol18 No.5: 1208-1221
【Title】Cryostructures and ground ice content in ice-rich permafrost area of the Qinghai-Tibet Plateau with Computed Tomography Scanning
【Author】FAN Xing-wen1,2;. LIN Zhan-ju1*; GAO Ze-yong1; MENG Xiang-lian3; NIU Fu-jun1; LUO Jing1; YIN Guo-an1; ZHOU Fu-jun3; LAN Ai-yu1,2
【Addresses】1 State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; 2 University of Chinese Academy of Sciences, Beijing 100049, China; 3 China Railway First Survey and Design Institute Group Co., LTD., Xi'an 71004, China
【Corresponding author】LIN Zhan-ju
【Citation】Fan XW, Lin ZJ, Gao ZY, et al. (2021) Cryostructures and ground ice content in ice-rich permafrost area of the Qinghai-Tibet Plateau with Computed Tomography Scanning. Journal of Mountain Science 18(5). https://doi.org/10.1007/s11629-020-6197-x
【Abstract】Permafrost is an important part of the cryosphere, playing an integral role in the hydrologic cycle, ecology, and influencing human activity. Melting of ground ice can drastically change landscapes and associated thaw subsidence may induce instability of infrastructure. The terrain conditions on the Qinghai-Tibet Plateau are complex, and the spatial distribution of ground ice is highly variable, so knowledge of its abundance and variability is required for impact assessments relating to the degradation of permafrost. This study examined 55 permafrost samples from warm, ice-rich permafrost region in Beiluhe Basin, Qinghai-Tibet Plateau. The samples were examined using Computed Tomographyscanning, and the ice content and cryostructure were determined. The results indicated that: 1) variation in volumetric ice content was considerable (0%-70%), with a mean value of 17%; 2) seven cryostructures were identified, including crustal, vein, lenticular, ataxitic, reticulate and layered cryostructure; 3) volumetric ice content varied by cryostructure, with the highest associated with layered and ataxitic cryostructures. Volumetric ice contents were lowest for samples with pore and lenticular cryostructures. This work provides detailed ground ice content and will be helpful for assessingthaw subsidence and infrastructure stability on Qinghai-Tibet Plateau.
【Keywords】Qinghai-Tibet Plateau; Permafrost; CT scanning; Volumetric ice content; Cryostructure