Research On Location Predicting Of Paleo-karst Sinkholes In Northern China Coalfields

The location of paleo-karst sinkholes is isolated,uneven distributed and difficult to predict.Accidentally exposing paleo-karst sinkholes always leads to water inrush accidents during coal mining,therefore,it is of great significance to predict its location.In order to predict accurately the possibility of development,the target area or the location of paleo-karst sinkholes,the factor prediction system,including 2 indexes at the first class,geological structure and karst development,and 10 indexes at the second,was established on the basis of main control factors for formation of sinkholes.According to the importance of indexes,each index was given different weights by using fuzzy comprehensive evaluation method.At the same time,the predicting information system is established,which could completes grid division,performs image processing and complete position calibration.The use of the system and information processing platform depends on the degree of data integrity in the study area.If data is insufficient,it could be used in the macro forecast.If data is enough,it could be used in semi quantitative prediction and ascertain location of sinkholes.This paper divides prediction theory into three levels: a.prediction of karst development degree in the whole mine,b.prediction of the location of paleo-karst sinkholes,c.prediction of the location of paleo-karst sinkholes on runoff zones.Based on the established prediction system,three typical mine areas in Northern China had been predicted and evaluated respectively.The development probability of paleo-karst sinkholes in Wugou Mine was predicted,and the comprehensive evaluation score was 84.9 which meant the paleo-karst sinkholes was likely to be found.Locations of paleo-karst sinkholes in Xingdong Mine were predicted on the basis of GIS platform,and the results showed that there were three most developed location,two relatively developed location.What is more,one paleo-karst sinkhole was discovered in the most developed location by the late project.Locations of paleo-karst sinkholes in Qianjiaying Mine were predicted on the basis of the predicted intensive runoff zones,and the results showed that there were 8 most developed target area and one paleo-karst sinkhole was discovered in the most developed area.The evaluation results indicate that the established prediction system can be used to predict locations of paleo-karst sinkholes,and the results accord with facts.This article included 70 figures,21 tables and 74 references.