The Hydrogeological Characteristics And The Influence Of Xujiazhuang-Limestone And Ordovician Limestone On Mining Lower-Group Coal In The Eastern Xinwen Coal Mine Area

This paper deals with the hydrogeological conditions and the characteristics of the groundwater seepage field in Xujiazhuang-limestone and Ordovician limestone, and the influence of Xujiazhuang-limestone and Ordovician limestone on the exploitation of lower-group coal in the east of Xinwen mine area. Based on the geophysical exploration data, drilling data and pumping test data, the author analyses the lithologic features, the thickness and their variation, and the water abundance of Xujiazhuang-limestone and Ordovician limestone, probes into the change and reason of water level of Xujiazhuang-limestone and Ordovician limestone, carries on the hydrogeological subdivision. On the bases of the generalization to the hydrodynamic condition, boundary condition, initial condition and source sink term impacting seepage field of Xujiazhuang-limestone and Ordovician limestone, using GMS, the hydrogeological conceptual model and numerical simulation model are set up, the characteristics of seepage field of Xujiazhuang-limestone and Ordovician limestone are analysed, the change of seepage field is forecasted under the condition of changeless actualities. the water inflow in different levels are estimated. Based on the lithology, thickness of aquifuge and their changes, the watertightness of aquifuge are evaluated. Synthetically considering all kinds of factors, such as water abundance of aquifer, structure influence, hydraulic pressure, watertightness of aquifuge, the influencing degrees that Xujiazhuang-limestone and Ordovician limestone on the exploitation of lower-group coal are analyzed and the danger zones of water inrush from floor are predicted using the way of water bursting coefficient. Finally, the technical approaches about the preventing and treating water disaster of Xujiazhuang-limestone and Ordovician limestone are put forward.