地质与勘探2026，Vol.62Issue(2)：388-397,10.DOI:10.12134/j.dzykt.2026.02.014
圆锥型瞬变电磁法在多年冻土勘探中的应用研究
The Application of Cone-Shaped Transient Electromagnetic Method in Permafrost Exploration
摘要
Abstract
Traditional transient electromagnetic method(TEM)has achieved significant results in permafrost exploration on the Qinghai-Tibet Plateau,but research on fine-scale detection under complex geological conditions remains insufficient.Maduo County in Qinghai Province,located in the Three-River Source region,features high altitude,cold climate,and frequent freeze-thaw cycles,making it a typical area with alternating distribution of permafrost and seasonal frozen ground.This study focuses on the alpine grassland area of Maduo County and employs the cone-shaped transient electromagnetic method(C-TEM)for permafrost detection research.Based on forward modeling of geoelectric models of permafrost in different degradation states,the capability of the cone-shaped TEM system in delineating permafrost layers has been confirmed.The simulation results clearly demonstrate the detection effectiveness of the upper and lower boundaries as well as the transitional boundaries of the permafrost layer.By systematically arranging 11 parallel survey lines to acquire TEM response data and combining borehole core analysis and geological data,the spatial distribution characteristics and physical parameters of permafrost in the area were studied.The research results indicate that the permafrost in the study area exhibits a zonal distribution,with thickness decreasing from north to south and a lower boundary depth of 35-45 m.Its distribution pattern is significantly controlled by regional fault structures and groundwater activity.The resistivity profile clearly reflects a three-layer structural character:the active layer,permafrost layer,and bedrock layer exhibit distinct resistivity differences,showing good correspondence with borehole and ground temperature data.In structurally complex areas,the integrated interpretation method of C-TEM combined with regional geological characteristics and hydrological information significantly improves the accuracy of permafrost boundary identification,providing a new geophysical detection approach for dynamic monitoring and change assessment of permafrost on the Qinghai-Tibet Plateau.关键词
地球物理/多年冻土/圆锥型瞬变电磁法/电阻率/黄河/青海Key words
geophysics/permafrost/cone-transient electromagnetic method/resistivity/Yellow River/Qinghai分类
建筑与水利引用本文复制引用
谷强,赵云,徐明元,许云磊,张耘硕,王国荣,杨海燕..圆锥型瞬变电磁法在多年冻土勘探中的应用研究[J].地质与勘探,2026,62(2):388-397,10.基金项目
中央财政项目:中国地质调查局"青藏高原多年冻土区地表基质摸底调查(青海)"项目(编号:DD20240101102)资助. （青海）
