Taking an integrated coalmine as example, put forward a combined surface and underground geophysical prospecting meth-od. That is, firstly through 3D seismic prospecting to delineate gobs distribution, then select one of the gobs to carry out surface tran-sient electromagnetic prospecting (TEM) to verify and determine its water bearing property, finally through underground TEM and drill-ing to accurately position abnormal region. A case study of a gob detection has shown that 3D seismic prospecting can obviously reflect strata continuity, preferably determine gob position and depth, but cannot interpret water yield property;TEM responds well to low-re-sistivity anomaly, can accurately reflect range of water bearing anomaly;while underground TEM and drilling because of nearer anoma-lies can obtain strata information better, thus more reliable to determine anomaly position.%以某整合矿井为例,提出了地面与井下物探相结合方法,即:首先通过三维地震勘探圈定采空区分布,在此基础上选择某一采空区作为地面瞬变电磁法工作区,验证采空区的含水性,最后通过井下瞬变电磁法及钻探实现对异常区域的精确定位.某采空区探测实例表明:三维地震勘探方法对地层连续信息反映明显,可较好的确定采空区的位置及深度,但对富水性无法解释;瞬变电磁法对低阻异常灵敏,可准确反映含水异常的范围;井瞬变电磁法及钻探因离异常距离较近,可更好的获得地层信息,对异常位置的确定更为可靠.
展开▼
