综合物探技术在煤矿采空区勘察中的应用

Application of Comprehensive Geophysical Prospecting Technology in Goaf Exploration of Coal Mine

煤矿采空区勘察是场地建设适宜性评价的基础,物探是采空区勘察的重要手段,瞬变电磁法和可控源音频大地电磁法在采空区的勘察中应用广泛。文章论述了瞬变电磁法和可控源音频大地电磁法的工作原理、参数选择和解译原则等,以济南市章丘某煤矿采空区勘察为例,对2种物探方法采集结果进行对比分析得到:①2种方法视电阻率变化趋势接近;②视电阻率总体范围变化不大;③采空区和断裂异常反映略有不同。2种方法推测结论基本一致,经钻孔验证,物探结果与钻探结果基本吻合,表明瞬变电磁法和可控源音频大地电磁法能有效查明采空区的分布情况,获得较好的地质勘察效果。

Coal mine goaf survey is the basis of site construction suitability evaluation,geophysical prospecting is an important means of goaf investigation.Transient Electromagnetic Method(TEM)and Controllable Source Audio frequency Magnetotelluric method(CSAMT)are widely used in goaf investigation.This paper discusses the working principle,parameter selection and interpretation principle of TEM and CSAMT.Taking a coal mine goaf exploration in Zhangqiu District of Ji'nan City as an example,the comparison and analysis of the acquisition results of the two geophysical methods show that:①the change trend of the apparent resistivity of the two methods is similar;②The overall range of the apparent resistivity changes little;③The abnormal reflection of the goaf and fault is slightly different.The conclusion of the two methods is basically the same,and the results of geophysical exploration are basically consistent with the drilling results,which shows that the transient electromagnetic method and the controllable source audio frequency magnetotelluric method can effectively find out the distribution of the goaf,and obtain better geological survey results.