强干扰区瞬变电磁法勘查采空区效果

THE EFFECTIVENESS OF APPLYING THE TRANSIENT ELECTROMAGNETIC METHOD IN HBIGH INTERFERENCE AREA TO THE EXPLORATION OF MINED-OUT AREAS

利用瞬变电磁法勘察采空区,当存在较强电磁干扰时,常规测量方式无法取得准确的测量数据。在北京房山区采空区勘查中,使用了一种具有抗干扰能力强的"8"字型测量方式,取得了较好的效果。通过剖面勘查以及相应的时间域电阻率成像资料处理法,获得了较高分辨率的电阻率剖面,推断出了采空区的空间分布特征,为在强干扰区勘查采空区提供了一种新的技术方法,也为治理和防止地面塌陷的进一步发生提供了科学依据。

The transient electromagnetic method is an effective method for detecting the distribution extent and characteristics of the mined-out area. Nevertheless, the measured data cannot be obtained accurately by common measurement mode of the transient electromagnetic method where there exists high electromagnetic interference. This paper introduces a ＂ 8＂-shaped grapheme measurement mode with strong anti-interference capability, with which a better mined-out area prospecting result was obtained in Fangshan District of Beijing. High resolution resistivity profile was got through profile prospecting and corresponding time domain resistivity imaging data processing. The distribution extent and characteristics of the mined-out area were also deduced. It is thus thought that this method can provide a new means for high electromagnetic interference mined-out area prospecting and the scientific basis for tackling and preventing land collapse aggravation.