微动和瞬变电磁法探测金矿采空区的效果分析及组合应用

Effect analysis and combined application of microtremor survey method and transient electromagnetic method in gold mine goaf exploration

对于老旧采空区精确探测是分析其稳定性、回收残矿以及综合治理的必要条件,而金矿采空区的地质情况更为复杂,精确探测的难度更大。在金矿采空区探测中,微动勘探的应用实例较为少见,而瞬变电磁则是较为常见的物探方法。通过在新疆哈密某金矿采空区进行探测试验,分析对比了微动和瞬变电磁组合探测的应用效果。结果表明:微动和瞬变电磁两种方法显示的异常区域较为一致,异常特征体现为“低速、低阻(充水)”,据此推断的采空区位置与已有矿山资料显示的采空区基本吻合。同时两种物探方法也体现出不同特点,微动可以准确地反映采空区的形态变化,识别采空区形态特征更加精细,瞬变电磁可以分析采空区的充水情况,提供的采空区信息更加丰富。

Accurate exploration is the primary requirement for stability analysis,residual ore mining and comprehensive treatment of goaf.However gold mining-induced goaf is difficult to detect accurately.In the exploration of gold mine goaf,the application of microtremor survey method is relatively rare,while transient electromagnetic method is a more common geophysical exploration method.A gold mine goaf was surveyed with microtremor survey method and transient electromagnetic method in Hami,Xinjiang Uygur Autonomous Region,and the results obtained from the two methods are compared.The study shows that the anomaly areas with the character of low velocity and low resistivity by the two geophysical exploration methods are basically identical;the inferred goaf position and morphology of the gold mine goaf are mainly consistent with the known mining data;the microtremor survey method is more accurate in identification of morphological feature of the goaf area,and the transient electromagnetic method can estimate water filling situation in the goaf.