层状全空间电测深曲线类型与新方法研究

Study on the curve-type and new method of layered full space electrical sounding

研究全空间直流电测深曲线的变化规律,为全空间直流电法的创新应用提供理论依据,采用理论计算层状全空间直流电测深曲线并统一归纳分类的方法,总结了全空间直流电测深曲线的类型和基本性质。结果表明,全空间条件下n层地层对应的曲线类型为2n-1种(n>0),且远比半空间的复杂;层状半空间曲线类型仅仅是全空间条件下记录点以上的地层电阻率为无穷大的特殊情况;在超高阻层存在时,半空间曲线尾支呈45°角上升的渐近线在全空间条件下其尾支渐近线变为0°角,由此发现全空间条件下直流电法探测低阻层比探测高阻层具有明显优越性。利用全空间直流电法这一性质,发展出许多煤矿井下全新的探测方法,为煤矿层状地层条件下的全空间直流电测深法探测低阻含水导水等隐伏灾害性地质构造指明了应用方向,丰富了全空间电测深理论。

In order to study the law of layered full space direct current sounding curve,the theoretical basis is provided for the innovative application of layered full space direct current method,and the method of theoretical calculation for DC sounding curve of layered whole space and unified classification method is adopted.The results show that under the full space condition the corresponding curve type of n formation is 2n-1（n〉0）,and more than half space complex,the curve type of layered half space is only a special case where the formation resistivity above the record point is infinite in a full space,in the presence of high resistance layer,the half space curve tail support asymptote 45 degrees rise in space under the condition of its tail to support asymptote at an angle of 0 degrees,it is found that the low resistivity layer than the detection of the high resistance layer has an obvious superiority under the full space condition.With the nature of full space direct current method,many new methods for detecting underground coal mines have been developed.This paper points out the application direction of the full space direct current resistivity sounding method for detecting concealed low hazard geological structures such as low resistivity water cut and water conductivity,and enriches the theory of whole space electrical sounding.