Abstract: At present,surface subsidence of coal mining is an increasing serious phenomenon，especially for shallow coal seam with thin bedrock in northwest China.Taking the mining area of a mine in Ordos as an example,the regularity and affecting factors of surface mining subsidence after mining of the first mining working face are analyzed.Based on the properties of the above strata,geological conditions,mining technical conditions and surface subsidence observation data of the mining area,the regularity of the first mining working face is analyzed by using probability integral method,and the main affecting factors of the surface subsidence in shallow coal seam with thin bedrock are also discussed in depth.The result show that:①the prediction results of the surface mining subsidence by using probability integral method is consistence with the measure data basically,therefore,it is feasible to predict the surface movement parameters in the mining area by using probability integral method;②the whole structure of the mining area is relatively simple,the coal seam of mining working face is distributed in horizontal,so,the factors such as thickness,mining depth,dip angle are changed slightly,through analyzing the above factors,it is believed that the ratio of the loose layer thickness and bedrock thickness (H_S/H_J) and mining intensity (advancing speed of working face) are the main affecting factors of the surface subsidence in the mining area;③the ratio of loose layer thickness and bedrock thickness (H_S/H_J),mining intensity (advancing speed of working face) curve and surface subsidence curve are analyzed,the roles of the ratio of loose layer thickness and bedrock thickness (H_S/H_J) and mining intensity (advancing speed of working face) to surface mining subsidence in mining area are opposite,the influence of mining intensity of (advancing speed of working face) is greater than the ratio of loose layer thickness and bedrock thickness (H_S/H_J)to surface subsidence in mining area.The above research results have certain reference value for analysis and prediction of the mining surface mining subsidence in Ordos area with stable geological structures.

Key words: Surface mining subsidence, Probability integral method, Affecting factors, Bedrock thickness, Loose layer thickness, Mining intensity