红柳林井田3^(-1)煤首采区顶板涌(突)水危险性预测

Risk Prediction of Roof Water Inrush in the First Mining Area of 3^(-1) Coal Seam in Hongliulin Minefield

陕北侏罗纪煤田浅埋煤层开采主要受顶板水害的威胁,顶板水主要包括煤层上覆风化基岩水及局部烧变岩水。风化基岩和烧变岩富水性强于正常基岩,受采动裂隙影响时,易引发涌(突)水事故。以红柳林井田3^(-1)煤首采区为研究区,针对顶板风化基岩含水层,选取了风化基岩岩性组合、风化程度指数、风化基岩厚度、岩心采取率及风化基岩顶面标高5种影响富水性的主控因素,利用GIS与AHP耦合的“富水性指数法”对风化基岩含水层富水性进行评价,将风化基岩富水性划分为强富水、中等富水和弱富水3类。针对烧变岩含水层,以瞬变电磁法物探、水文钻孔单位涌水量及井下探放水资料为基础,将烧变岩富水性划分为极强富水、强富水、中等富水和弱富水4类。根据导水裂隙带高度发育特征,进行顶板含水层破坏程度分区,结合含水层富水性预测结果,分析预测了研究区3^(-1)煤顶板涌(突)水危险性。将研究区顶板涌(突)水危险性划分为:危险性极大、危险性大、危险性中等和危险性小4类。该预测结果可为红柳林煤矿3^(-1)煤开采过程中水害防治提供指导。

The mining of shallow coal seam in the Jurassic coalfield in northern Shaanxi is mainly threatened by roof water damage,which mainly includes weathered bedrock water and locally burnt rock water overlying the coal seam.The water abundance of weathered bedrock and burnt rock is stronger than that of normal bedrock.When affected by mining fissures,it is easy to cause water inrush accidents.Taking the first mining area of 3^(-1) coal seam in Hongliulin minefield as the research area,five main controlling factors affecting water abundance were selected,including lithology combination of weathered bedrock,weathering degree index,thickness of weathered bedrock,core recovery rate and top surface elevation of the weathered bedrock.The water yield index method coupled with GIS and AHP was used to evaluate the water yield of the weathered bedrock aquifer,and the water abundance of weathered bedrock was divided into three categories,including strong water-rich,medium water-rich and weak water-rich.For the burnt rock aquifer,based on the transient electromagnetic geophysical prospecting,the unit water inflow of hydrological drilling and the underground water exploration and drainage data,the water abundance of burnt rock can be divided into four categories,including extremely strong water-rich,strong water-rich,medium water-rich and weak water-rich.According to the height development characteristics of the water flowing fractured zone,the damage degree of the roof aquifer was divided.Combined with the prediction results of the water abundance of the aquifer,the risk zoning of water inrush from the roof of 3^(-1) coal seam in the research area was analyzed and predicted.The risk of water inrush from the roof of the research area was divided into four categories,including extremely dangerous,large dangerous,medium dangerous,and small dangerous.The prediction results can provide a guidance for water hazard prevention and control during the mining process of 3^(-1) coal in Hongliulin Coal Mine.