Fluid Discrimination Method Based on the Prestack Inversion
This paper discusses how to directly obtain the P-impedance and S-impedance through EI inversion based on a new elastic impedance equation which deduces from the Fatti Zoeppritz approximation. It also analyzes some conventional fluid identification factors and gives a universal expression of the fluid identification factor. Finally, the authors propose a new high sensitivity fluid identification factor based on the gassman equation and other effective rock physical theories. A example of the application indicates that the new factor is more sensitive and applicable than other conventional ones.