Abstract: The velocity ratio of compressional and shear waves in gas saturated rocks is less than that in water saturated ones when their porosities and confining pressures are the same.this paper have proposed an interpre-tation technique for visually identifying gas formation in which measured velocity ratio of compressional and shear waves is shown by a contrast with its background value.A formation is indicated as gas producing when the measured velocity ratio is less than the background one.This method has been tested and verified with neutron and density porosities as well as flushed zone and initial water containing formation porosities.It enhances the ability and accuracy of visual indication gas formation.Field examples are demonstrated.