复杂地质条件下覆岩导水裂隙带钻孔窥视与实测分析

Borehole Observation and Measurement Analysis of Water-conducting Fracture Zone in Overlying Rock under Complex Geological Conditions

为探明郭屯煤矿复合煤层开采过程中覆岩导水裂隙带的发育规律,共计施工3个地质钻孔,分别对3上煤层,3上煤与3煤复合煤层开采导水裂隙带进行实测。通过监测钻孔单位时间与单位进尺冲洗液消耗量与水位变化量,并利用钻孔窥视技术对导水裂隙带高度进行预测。将多种实测方法下分析的导水裂隙带高度进行对比,结果表明:钻孔冲洗液漏失主要原因是洛河组上部的衍生的大量水平裂隙,3上煤单煤层开采导水裂隙带发育高度181.93 m,复合煤层开采导水裂隙带发育高度259.03 m。

To explore the development law of the water-conducting fracture zone of overlying rock in the mining process of composite coal seam in Guotun coal mine,a total of 3 geological boreholes are constructed,and the water-conducting fracture zone of the mining of 3 upper coal seam,3 upper coal seam and 3 coal composite coal seam are measured respectively.By monitoring the flushing liquid consumption and water level variation per unit time and per unit footage of drilling,the height of water-conducting fracture zone is predicted by using the borehole observation.The results show that the main reason for the hole flushing fluid leakage is the large number of horizontal fractures derived from the upper part of Luohe formation.The development height of the water-conducting fracture zone in single coal seam mining of 3 upper coal is 181.93 m,and that in composite coal seam mining is 259.03 m.