Abstract: To analyze the lithology and fracture characteristics of overburden in high-intensity mining face,focusing on 20313 working face in Gaojialiang Coal Mine,The distribution of roof aquifers were analyzed. The microstructure,mineral composition,physical and mechanical properties of sandy mudstone were obtained by experiments. Physical test,theoretical analysis,magnetotelluric detection and field survey were used to analyze the overburden failure. The results show that with the increase of the distance from the coal seam to the sand mudstone of the working face,the contact between parti-cles gradually changes from point-point and point-surface contact to line-surface and surface-surface contact,and the vol-ume of particles tends to increase. From the coal seam to surface,the tensile (compressive) strength decreases,the con-tact area after fracture is larger,and the volume of particles expands after water encounters,the pore space between parti-cles is squeezed,the pore passage is reduced,and the macroscopic water permeability is reduced. Overburden and surface fissures develop repeatedly in the process of opening,closing and compacting. Although overburden aquifers and imper-meable layers have been damaged,the width of fissures is small,and there are no obvious collapse fissures on the sur-face. After mining,a stable pressure arch structure will be formed in overburden. Rock fissures will not connect with sur-face and the surface water will not directly connect with underground working face. The destruction of strata on the side of the upper wall of fault is more serious. On the lower side of the fault,although there are many circular closure curves in the nephogram of CAN,there are still smooth layered curves wrapped up,which indicates that the continuous distribu-tion of mining overburden is good and the development degree of cracks in the strata is low. After mining in 20313 work-ing face,most of the surface cracks are mainly tension or compression cracks,and the cracks is few. All cracks have un-dergone a complete development process of “opening-expanding-closing”. The longest development period is 15 days,the shortest is 7 days;the largest crack width is 6. 3 cm,and the largest step drop height is 8. 7 cm. The growth and distribu-tion of surface vegetation are basically the same as before mining,which indicates that the safety of mining and surface e-cology are not affected. A large number of theoretical and experimental studies have been carried out on the development characteristics of overburden fissures in high-intensity mining. Geophysical prospecting is the most convenient and fast method to detect the in-situ overburden fissures. Improvement on the sensitivity of geophysical instruments to overburden fissures detection and the accuracy of interpretation of prospecting results are the technical prerequisites for the populari-zation of geophysical prospecting to detect overburden fracture.