Taking a mine area in the northern Shanxi as an example, relying mainly on coincident loop transient electro-magnetic method, supplemented by DC resistivity profiling method with two AB distances carry out gob area water-bearing property applied research. In composite symmetric four—electrode DC resistivity profiling, using small AB/2 distance 40m, the large one 160m carried out comparison test on fixed MN distance and MN/AB ratio 1/4, and comparatively studied different apparent resistivities when large AB distance is 320m. The result has demonstrated that the impacts from relief and MN grounding resistance are rather large, while the apparent resistivity ratio in composite symmetric four-electrode resistivity profiling can reduce such disturbances preferably. The case has shown the transient electro-magnetic method is propitious to be popularized widely in whole area, after the key water-bearing anomaly area is preliminarily interpreted, then carry out detection with four-electrode composite resistivity profiling, and using composite symmetric four—electrode apparent ratio method to confirm water yield property in gob area, the result will be more reliable.%以晋北某矿区为例,选择使用以重叠回线瞬变电磁法为主,2个AB极距的直流电阻率剖面法为辅的物探方法,开展采空区含水性探测应用研究.复合对称四极直流电阻率剖面中小的AB/2极距为40米,大极距为160米,研究中分别对对固定MN极距20米与MN/AB比值1/4进行了对比试验,并就大极距AB为320米时的不同MN视电阻率进行了对比研究,结果表明直流电剖面法受地形和MN接地电阻的影响较大,而复合对称四极电阻率剖面的视电阻率比值可以较好地减少这种干扰.实例表明瞬变电磁法在采空区含水性探测中适合全区大面积开展,在初步解释得到含水重点异常区后再进行对称四极复合电阻率剖面探测,并利用复合对称四极的视电阻率比值法确定采空区富水性,其成果会更可靠.
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