The Method Of Screening The Hidden Geologic Hazard And Safety Evaluationin Mining Area Based On SBAS-InSAR

Due to the development of coal resources,it causes geological disasters such as ground cracks,ground collapse and ground subsidence in mining area.The damage to the buildings and roads in the mining area will affect the economic development and damage the ecological environment.Therefore grasping the information of development degree,hidden danger point,scope and risk of geological hazards in mining area comprehensively and timely is great significance to the sustainable development of economy and geological disasters' control and prevention.This paper carries out the ground subsidence and the screening of hidden geological hazards with SAR dates based on SBAS-InSAR technology in jiaozuo city's mining area.The method of screening hidden spots of ground fissures,ground collapses and ground subsidence is proposed.This paper constructes the safety evaluation index for geological disasters and uses the method of fuzzy comprehensive evaluation to evaluate the risk of geological disaster in the study are.The main conclusions are as follows:(1)How to select the interference combination of high coherence and how to select the GCP point accurately is the key to improve the monitoring accuracy of SBAS-InSAR Technology.This paper determines the relationship between coherence and time baseline,space baseline and Doppler shift by the method of regression analysis and selects the best method of interference combination.Proposed the method of setting up the settlement threshold to select the PS point as the alternative GCP point.(2)According to the geological disasters have different effects on different objects,the main objects are extracted by remote sensing interpretation using the data of high score 1.The hidden points of geological disasters are extracted by setting the threshold method respectively through superposing the results of the classification and ground subsidence.The results of geological disasters including a high-rise building,three low floor buildings.The results of hidden geological disasters including two high-rise buildings,three low floor buildings,highway 7.2km and railway 3.9km.(3)According to the characteristics of ground subsidence and ground fissures in the study area,four ground collapse pits were extracted by remote sensing image interpretation.A method of identifying ground fissures is put forward based on tectonic subsidence slope map and one ground fissure is monitored.(4)The evaluation factors are ground subsidence,ground subsidence,ground fissure,ground cover,ground slope and mine distribution.The method of seting weight is the analytic hierarchy process.The geological hazard of Macun District of Jiaozuo has been evaluated by grid type through using the method of fuzzy comprehensive evaluation.The geological hazard which is high and prone to occur is the northeast and the middle West in Macun area.The degree of highest susceptibility accounted for 4.6%,higher susceptibility accounted for 6.6%.The total amount is 11.2%.It is the area where key prevention and control are needed.It has important practical value for disaster prevention and disaster reduction and scientific development in mining area.