Abstract:Tomographic imaging for cross-hole seismic velocity can be used to solve the problems such as lateral connectivity of reservoir and caprock in cross-hole and vertical contacting relation in oilfield; tomographic imaging for cross-hole Q value can reflect the absorption of elastic wave by cross-hole medium and can be used to evaluate respective reservoir parameter.It can describe precisely the cross-hole reservoir by using synthetically the kinematic and dynamic features through using travel time and frequency feature of cross-hole seismic first break for joint tomographic imaging for seismic velocity of stratum and for Q value. For the purpose of fixed-solution problem for finding solution of cross-hole seismic medium distribution,forward problem based on seismic ray imaging algorithm consists of two parts: integration of seismic wave slowness along ray represents a time field; integration of attenuation factor along ray reflects absorption of medium.Both of them can be characterized by structural similar Radon transform.Therefore,pressing measure is basically same in inverse problem and facilitate to fulfill the joint tomographic imaging.Seismic first break acquired from cross-hole reflects variation of transmission wave frequency with stratum and reservoir,so it can strengthen knowledge of reservoir parameters by studying a relaticn of seismic wave frequency to attenuation factor.