Study on movement law of ultra thick overlying strata broken and coal mine earthquakes

Based on the theory of overlying stata movement laws and rock burstaking No.103 upwork face at ten mining blck in Baodian Mine as the study obje:t.the movement law of ultrathck overying strata broken and the factors induced coal mine earthquakes were reseached by computer umeriealsimulation and theoretcal analysis.The relativity between overying stata movement and mine earthquakes wvas verfie though analyzng site micr-sesmie dat .Theresuis shovedtht efore the red sandstone broken.the two inferior key strata moved fogether above work face small mine earthuakesocured frecuentiy t the whole wark face under themicro earthquake energy 104 .Wmen the work face advanced t 350 m,the red sandstone broken a frst time and the strong earthouakes ocured frequerntiy under themicro earthquake energy105 J.The earthquakes events of red sandstone distributed with O一X form on the plane and developed from botom to central in secion.