煤矿浅埋老窑采空区多梯度剖面装置探测研究

A Study on Multi-gradient Profiling Array in Detection of Coalmine Shallow Gob Area

以内蒙某露天煤矿的地质特征为依据,建立二维正演模型,利用改进的高密度电法装置——多梯度剖面装置进行采空区在埋深、充水性、规模等不同条件下的正演响应分析,总结出高、低阻模式下异常响应都会随采空区深度的增加表现为幅度减少,且埋深大于采空区直径的3～5倍时,其正演剖面上难以显示出异常特征。以煤层顶板为30m的数据进行反演,发现高阻异常的反演结果与理论模型在位置、宽度、顶部埋深和电阻率值方面吻合程度较高;而充水采空区,异常的规模存在一定误差。内蒙某露天煤矿的勘探实例,验证了多梯度剖面装置在浅埋采空区勘探中,可以取得较理想效果,特别是对不充水采空区,其准确度更高。

Taking geological features of a surface coalmine in Inner Mongolia as the basis, estabhshed a 2D forward model, using an improved high density electric device-multi-gradient profiling array carried out forward response analysis of gob area under different depths, water filling properties and dimensions. Summed up the anomalous responses under both high and low resistances will appear along with amplitude reducing, gob area depth increasing. When depth is more than 3-5 times of gob diameter, thus hard to show anomalous features on forward section. When using 30m coal roof data to carry out inversion, have found the fitness of high resistance inversion result with theoretical model is rather high on aspects of position, width, gob top buried depth and resistivity value; while has certain errors in dimension of anomaly in water filled gob area. The actual exploration example of an Inner Mongolia coalmine has validated that the multi-gradient profiling array can get rather ideal effect in shallow gob area detection, especially in gob areas without water filling has higher accuracy.