Cryostructures and ground ice content in ice-rich permafrost area of the Qinghai-Tibet Plateau with Computed Tomography Scanning

• 作者: FAN Xing-wen LIN Zhan-ju GAO Ze-yong MENG Xiang-lian NIU Fu-jun LUO Jing YIN Guo-an ZHOU Fu-jun LAN Ai-yu
• 来源期刊: 山地科学学报（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: Mountain Environment
• 页码范围: 1208-1221
• 页数: 14页
• 语种: 英文

摘要

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 Tomography scanning,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 withlayered 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 assessing thaw subsidence and infrastructure stability on Qinghai-Tibet Plateau.