0 for the movement of overlaying strata and fracture development caused by the mining of upper protective layers of coal seams with close quarters.

After in situ engineering geologic investigation,the systematic analysis of the relation between the regularity of joint fissure development in country rock area and the geologic structure was made with the help of the theory of geologic mechanics.

Evolution of rock joints into transfixion is described by the time series from strain-stress curves,and the state of joint system in sandstone is chaotic before its ultimate state.

Rock joint network is complex.

By rock mechanical experiments of rock material test system, scanning electronic microscope and optical microscope, this project finds three typical strain-stress curves of sandstone specimens and discusses damage mechanism of joints in micro, mecro and macro sizes.

The application of seismic attribute technique to predict Ordovician limestone karst fractured zones;

In predicting Ordovician limestone karst fractured zones, the wavelet transform can enhance signal/noise ratio (S/N) and the resolution of seismic signals; the parameter of two-dimensional fractal has its own value; and the combination of them is an eff.

The research of faults and fractured zones is very important in coal mine security and production.