Taking a typical iron mine as the background engineering

the discontinuities of rock mass were revealed by the field geological survey and borehole camera technology; and based on the results of deformation monitoring including the global positioning system(GPS)

leveling measurement

fissure extensometer monitoring and borehole deviation surveying

the influence of discontinuities on rock movement and surface deformation caused by underground mining is analyzed. Results obtained indicate that: the special geological structures such as faults and joints have an important influence on rock movement and surface deformation; the actual deformation direction and value are different from theoretical prediction. The NNE- and NE-trending discontinuities control the lateral boundary conditions of movement of the rock mass

which cause the deflection of the direction of the surface movement. The NWW-trending discontinuities cause toppling deformation towards mined-out area; and the ground subsidence shows three-level ladder shape in this direction in eastern main shaft area. The smaller surface deformation and rock movement in western ventilating shaft area is resulted from its relative location with two gobs and the influence of the NE-trending discontinuities