ANALYSIS ON THE ABSORPTING CHARACTERISTICS OF ELECTROMAGNETIC WAVE IN COAL SEAM WITH SOFT COAL, ROOF AND FLOOR

Based on the tunnel transmission tests on both working faces in Liangjia mine,the absorpting coefficient β of electromagnetic wave in coal seam with soft coal,roof and floor is found;using the absorpting chromatograph charts of working faces obtained by the CT technique processing,the absorption abnormal characteristics of fractures and structures in coal seam with soft coal,roof and floor are analyzed,and the better geological effectiveness is obtained.