摘要
利用不同埋藏深度和倾向的板状体模拟含水裂隙和采空区,通过简单的理论计算,给出了瞬变电磁法的定源回线中心测量和重叠回线装置对该含水地质体的二次场响应特征。理论分析与实测数据表明,定源回线中心测量和重叠回线装置的含水地质体的视电阻率异常特征较大差异,对于含水采空区,前者表现为低视电阻率,后者则显示为高视电阻率;对于含水断层裂隙,二种装置的视电阻率拟断面图均表现为视电阻率等值线的近似直立。另外对于瞬变电磁二次场,定源回线中心测量装置会在含水地质体最浅部的地面投影点附近存在一个过零点,过零点两侧二次场的极值大小决定了含水地质体的赋存形态;重叠回线装置会在含水地质体最浅部的地面投影点附近存在一个极小值,极小值两侧二次场的极大值大小可确定含水断层裂隙的倾向。
Using different buried depths and dips tabular bodies to simulate water-bearing fissures and gob area, through simple theoretical arithmetic, have provided the water-bearing geological body secondary field response characteristics through TEM fixed source loop central surveying and superposed loop surveying. The theoretical analyzed and measured data have shown that the apparent resistivity anomaly characteristics of water-bearing geological body from the two methods are different. To water-bearing gob area, the former appears as low apparent resistivity, while the later high apparent resistivity; to water-bearing faulted fissures, the apparent resistivity pseudosection maps from the two systems are almost upright. To TEM secondary field, the former has a crossover near water-bearing geological body shallowest ground zero, secondary field extreme size of both sides of crossover decides water-bearing geological body occurrence mode; the later has a minimal value near water-bearing geological body shallowest ground zero, maximal value of both sides of minimal value decides water-bearing faulted fissures dip.
出处
《中国煤炭地质》
2015年第3期70-76,共7页
Coal Geology of China
关键词
采空区
断层裂隙
定源回线中心装置
重叠回线装置
视电阻率
瞬变电磁法
gob area
faulted fissure
fixed source loop central surveying system
superposed loop surveying system
apparent resistivity
TEM
