RI 3555 Use Of Subaudible Noises For Prediction Of Rock Bursts ? Introduction

[Tng occasional. rock noises in a nice caured by brc,*ing and ripping of the back, settling, and other cailscr, are well-known tc~ a11 mining en- gineers. These noises oftcn prececte certnin tpes of rock failure as such are used to e certain event a; w:,rnlngs. Senides t5ese audible rock noisee t'nere are, l?o\;evpr, even Iprger nw.iber of' s;Lba.J^;li5le rock mis~s, which must; be piclcell UT with sole type of vi-urr,tion rnicroyhoce and qli- fied in order tnnt :hey n;ny e heard. It v:zs s~v;,yestec" Ir, an evlier ? ,I a.ldible noises Ifureau of I.lines s~zb:ic;et.iod that n stud:r of t!ler;c! *- t mig!!t be useful ir. de temining roc^ movemrnt 3 preceding failure.]