Interpretive PP and PS Joint Inversion

Hongbo Zhang

The method of joint PP-PS inversion has recently been developed and tested on the 3-D Blackfoot seismic data set. This thesis shows the application of this method on 3C-2D seismic data from Pikes Peak oil field. The inversion was accomplished with a newly installed inversion module in ProMAX. Ten datasets that were carefully prestack processed, migrated and correlated, together with the RMS amplitude values and a background velocity model, were input into the joint PP-PS AVO inversion module in ProMAX. Four attributes were determined: fractional compressional-impedance contrast I/I, fractional shear-impedance contrast J/J, fractional contrast ()/ and fractional / contrast (/)/(/).

Good correlation of these parameters from seismic inversion and those calculated from well logs shows that joint PP-PS AVO inversion can be used to indicate anomalous lithology and pore-fluid changes in the subsurface. Therefore it should be helpful in detecting hydrocarbons using 2-D multicomponent seismic data.