Abstract：The deep and large faults in upper crust are often accompanied with low velocity layer stretching from several hundreds meters to several thousands meters in deep underground, which plays an important controlling role in hydrocarbon accumulation and migration or wreck of reservoir. understanding its 3-D configuration,size,dipping and physical parameters(such as wave velocity and Q value etc.)play an important role in guiding hydrocarbon exploration. The fault zone trapped waves approach is effective method for accurate determination of geometric shape and physical parameters of faults. The paper gave the computation formula and steps determining the internal physical parameters of fault zones, developed a set of software comprehensive using fault zone trapped waves and body waves(P-wave and S-wave)to determine the geometric shape and physical parameters of faults and also gave the application cases analyzing and computing trapped waves. The study and application results showed that using fault zone trapped waves could preliminarily determine the structure, continuous feature with depth and physical parameters of faults by spectrum analysis method;by the aid of travel time and waveform data of trapped waves, and body waves, and using spectrum analysis and ray-tracing method can further determine the 3-D geometric shape and physical parameters of faults.
