济宁市王楼煤矿侏罗系含水层水文地质条件分析

Hydrogeological Condition Analysis for Jurassic Aquifers in Wanglou Coalmine,Jining City

王楼煤矿目前正在开采3上煤层,主要水害为顶板水和采空区积水。顶板水主要水源为3煤顶部砂岩水及侏罗系砂砾岩水,其中侏罗系砂砾岩水是矿井防治水工作的主要对象。区内局部地段侏罗系砂砾岩含水层直接覆盖在煤层露头之上,成为3煤层开采的直接充水含水层。运用历年来的抽水试验成果及水位动态变化资料,对侏罗系含水层的水文地质特征进行了分析,并对断裂构造对含水层及矿井充水的影响进行了评价。结果表明:侏罗系下部砂砾岩段大部地区富水性弱-中等,是开采浅部煤层时矿井的主要补给水源之一;上侏罗统砂砾岩裂隙含水层与山西组3上煤层顶底板砂岩水存在较好的水力联系;在区内该含水层除二段上部富水性较弱外,其余的层段富水性均较强,主要接受上部岩浆岩含水层的补给;煤层开采造成的冒落裂隙带在局部地段影响到侏罗系含水层,从而使侏罗系含水层成为煤层开采的直接充水水源。

At present,the Wanglou coalmine is in course of coal No. 3 U extraction,while the main water hazard is from coal roof aquifer and gob ponding. The roof aquifers have coal No. 3 roof sandstone and Jurassic sandy conglomerate,the later is the main target of coalmine water control. Locally,the sandy conglomerate aquifer is directly overlying on coal outcrops,thus the immediate water filling aquifer during the coal No. 3 extraction. Using the pumping test results and water level dynamics over the years,carried out analysis for hydrogeological features of Jurassic aquifers,and assessed impacts from faulted structure on aquifer and coalmine water filling. The results have shown that in most areas,the water yield property of Jurassic lower part sandy conglomerate sector is from weak to medium,one of the main recharge sources during the shallow part coal mining. Between the upper Jurassic sandy conglomerate fissure aquifer and the Shanxi Formation coal No. 3 U roof and floor sandstone aquifers have better hydraulic connection. Besides the upper member of sandy conglomerate fissure aquifer has weaker water yield property,the rest parts are rather strong and mainly recharged by overlying magmatic rock aquifer. The coal mining caused caving fissure zone can locally impact Jurassic aquifers,thus enabling them become immediate water filling sources during the coal mining.