| As China's major coal production base, the North-China-Type coalfields mostly distribute in karst areas, and the major water disaster problems of which are the roof and floor water bursting. So it has great realistic meanings to find out the condition of coalmine water disaster for the coal-mining safe. However, due to the complex hydro-geological condition of the karst mining and a strong spatial and temporal variability of karst water-bearing media, it makes the flow rate and delivery head of karst water often have a strong randomness. In addition, the impact of coal mining activities under the water pressure of Ordovician limestone makes the gushing water more complex. Such factors make the water-inflow prediction of karstic water-filling deposits is not accurate enough, which directly impacts on the prediction, prevention and control of mine water disaster. So. collect and analyze systematically the survey region and mine area's basic document of meteorological, hydrological, geological and hydro-geological, and incorporate the data of pumping test, water inrush, underground observations and geophysical (electromagnetic), based on which the risk of karst water inrush is evaluated comprehensively by using information fusion technology. This study not only has a very important theoretical significance, but also has a great practical significance to the study of mine water inrush.Based on the groundwater system theory, this paper makes a base study of Wanghe coalmine. Firstly the regional geological and hydro-geological conditions are collected and analyzed. Focusing on water-rich section, the hydrodynamic and hydro-chemical characteristics in the regional karst water system, as well as exploring characteristics of Karst water hosting and migration, the conditions of groundwater recharge, runoff and discharge in Wanghe mine area, we discuss the impaction of these factors on the mine water-filling. Further more, on the base of above study; the author analyzes the water abundance of aquifer, hydraulic relationship between aquifers and dynamic pit inflow of water and so on. After these, with the actual situation of Wanghe mine water inrush, summarize the important control indexes, build an indexes system of mine water risk evaluation for top group of 1st coal seam. After that, combining analytic hierarchy process (AHP) with entropy weight coefficient method (EWM) to determine the index weight of the general objective, in order to construct a risk assessment model for water inrush. And then do spatial overlay analysis among water inrush index thematic maps through multi-information merging technique of GIS, calculate to acquire water inrush index of the range of Wanghe coalmine, based on which generate risk zoning chart of the mine water inrush. At the end of this paper, the writer points out that the focus of future prevention and control of mine water inrush, which provides a scientific basis for drawing up an effective plan mining safety under pressure in coal mining work face.The result shows that:(1) Wanghe mine is in the strong discharge zone of the regional flow systems, modern precipitation is the main recharge resource of mine water, and mine drainage is the main discharge method for kart groundwater. The groundwater in the limestone formations (E2z-O2m) exposes in the south of coalfield recharged by the precipitation, and then flows to northern coalfield where the O2m aquifer is underlain the coal formation. At present, by mines continued to drain, there has been large-scale groundwater depression, and the funnel Center is located at 111070 working face. Dynamic characteristics of karst water is that Karst water level continued to decline for the past many years, this phenomenon shows that storage resource has been consumed in mine drainage and the Karst water system is in a state of negative equilibrium. Hydrochemistry and isotopic analysis showed that Wanghe coalmine is in the discharge zone of the regional flow systems; the groundwater exposed in the south of coal field is recharged by the precipitation, and then flows to northern coal field where the O2m aquifer is underlain the coal formation in lateral and vertical movement. In the coal field the groundwater moves through long distance and velocity is slower than that in the recharge zone so that the water quality is more complex than that in the recharge zone.(2) The mining safety for top group of 1st coal seam threatens by the 1st to 3rd coal seam roof Taiyuan group limestone aquifer and coal seam floor fractured Ordovician limestone karst aquifer, both of which aquifers have closely hydraulic connection and synchronous response.(3) The important control factors of mine water inrush for Wanghe coalmine contain five aspects, which include aquifer water yield property, head pressure with Ordovician limestone karst water to the lower bed of aquifuge, thickness of aquifuge, complexity of geological structure and rock pressure. So, four evaluation indexes are chosen, which contain aquifer water yield property, head pressure with Ordovician limestone karst water, thickness of aquifuge and mining depth, and then calculate the weight of evaluation indexes by the means of AHP and EWM. The results provide that thickness of aquifuge and influence of aquifer water yield property is the most obvious indexes, behind which is head pressure with Ordovician limestone karst water, and mining depth is also very important.(4) For mining top group of 1st coal safely in Wanghe coalmine, This paper give a complicated assessment on water inrush, with multi-originated information complex fusion based on GIS, AHP and EWM. Based on GIS's strong spatial analyzing, overlay different spatial thematic layer with different weight contribution ratio defined by AHP and EWM to a composite to Pological layer, and use the model of water inrush index to calculate water inrush index. After getting an evaluation division, we make a fitting and verifier on it. The result shows that it has some higher accuracy of VI. And it also shows there exists terrible danger zones and danger zones in water-rich aquifer and thickness of water-resisting layer in deep area, and has a relation with aquifer water yield property, water pressure, thickness of aquifuge and mining depth.
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