Application And Research Of The Inversion Technology In Bohai Oilfield's Exploration Development

Along with the incessant development of oil-gas Exploration development, the aim of Exploration is developing from structure reservoir to structure and lithology composite stratum lithology reservoir. Research direction is changing from structure interpretation to structure integration research,reservoir identify and hydrocarbon detection, And driver the naissance and development of application technology in exploration field, Especially the extend application of pre-stack time migration and pre-stack inversion technology, make great contribution for exploration activity, It is the relatively mature key technology in exploration field.As we know, general post-stack wave impedance inversion technology is build the base of seismic wave vertical incide reflection interface, in the CMP trace together ,short offset distance correspond to seismic trace and seismic wave nearly vertical incidence the reflection interface , use this general method of seismic trace inversion can obtain the better effect. But, Practical seismic data is not the seismic record of self-explode and self-incept. The result of CMP trace gather is reflection amplitude, it is not mean the change of reflection amplitude along with difference offset distance or difference incidence angle .that is AVO phenomena. Especially the offset long distance, there are more difference between the reflection coefficient of vertical incidence and the reflection coefficient of fact stack trace. If they independency apply, it do not stand the reality information of reflection amplitude. In order to overcome the default of post-stack inversion, adopt the data of pre-stack to invert, it can stand the change of reflection amplitude along with the offset. For the far offset distance, should be renew by the function of elasticity wave impedance, the inversion of elasticity wave impedance can overcome the default of general post-stack inversion, combine the AVO problem with trace inversion. Due to can save the AVO character change from CRP trace gather to angle trace gather, by elasticity wave impedance inversion, can obtain more liquid information, that can stand rock physical character, as P-wave impedance,S-wave impedance,P-wave velocity,S-wave velocity,aspect ratio,Density and Poisson ratio and so on, elasticity wave impedance inversion has obvious advantage than the general post-stack inversion.