多方面研究(Moebs,1974·1977·1981;Ferm等1978;Moebs和Ellenberger,1982;Nelson,1981;Iannacchione等1981;Milici等1982)已经证明:一定的地质条件是影响煤矿井下顶板稳定性的重要因素.它包括:古河床、侵蚀、尖灭、粘土矿脉,裂隙发育(Moebs和Ellenberger 1982)以及断层和具有光滑擦痕面的断裂构造(Mi-lici等1982和Iannacchione等1981).这些影响因素被系统地收集在表1内. Various studies (Moebs 1974-1977-1981 Ferm et al 1978 Moebs and Ellenberger 1982 Nelson 1981 Iannacchione 1981 and Milici et al. 1982) have demonstrated that certain geological conditions are important in influencing the stability of a coal mine roof (Moebs and Ellenberger 1982) as well as faults and fault structures with a smooth scrubbed surface (Mi-lici et al. 1982 and Iannacchione et al. 1981). These influencing factors include the ancient riverbed, erosion, pinch out, clay veins, Is systematically collected in Table 1.