地下三维体上电测深曲线规律

来源期刊：中南大学学报(自然科学版)2001年第5期

论文作者：肖志强 鲍光淑 敬荣中

文章页码：448 - 452

关键词：边界积分方程法;温纳尔测深;对称四极测深;数值模拟

Key words：boundary integral equationmethod; Wenner array sounding; symmetric four-pole sounding; numerical modeling

摘    要：以均匀半空间中等轴状三维地质体为例,利用边界积分方程法对对称四极和温纳尔2种装置的电测深进行数值计算,并与相应解析表达式的计算结果进行对比;用数值模拟方法研究了均匀半空间中板状体的对称四极、温纳尔等装置电测深拟断面图“看得见但看不穿”的规律.研究结果表明:温纳尔、偶极等测深装置不仅能“看到”而且能“看穿”地下三维体,而对称四极装置及交流电法中采用平面波场的CSAMT,AMT等观测方式通常只能“看到”但不能“看穿”三维异常体;在对称四极测深装置中心剖面上,根据水平板状体的规模及埋深等因素,可分别将其视为一维层状体或均匀半空间处理,这对野外实际工作具有指导意义.

Abstract: Using boundary integral equation method, the authors calculate the results of symmetric four-pole sounding and Wenner array sounding for an equiaxial 3-D body in homogeneous half-space, and proves that the results are correct by comparing the results with calculating results of relevant analytic equation. Based on it, the authors, using the pseudosection map of symmetric four-pole sounding and Wenner array sounding in homogeneous half space, further study some rules of “ can see the 3-D body but cannot penetrate it”and conclude that Wenner array sounding, double-pole sounding and others can not only see the 3-D body but also penetrate it, but symmetric four-pole sounding and CSAMT,AMT, and other observation manners, which use plane wave,among alternating current methods can only see the 3-D body but cannot penetrate it. Level flat underground can be treated as 1-D stratumbody or homogeneous half-space when we observe on center profile using symmetric four-pole sounding accordingto the magnitude, burying depth of level flatetal. The above rules are important for our field work.