The prediction of Jurassic gas-sand with low water saturation using seismic-derived density property —A case study from Sichuan Basin

Summary Rock physics study shows that Jurassic gas-sand with low water saturation (Sw) is highly correlated to density properties. Moreover, density property of Jurassic gas-sand is much less than that of shale. Seismic-derived density property is used for the prediction of Jurassic gas-sand with low water saturation. Density contrast (reflectivity) is derived from 3D pre-stack time migrated CRP gather data and velocity data, and then density reflectivity are inverted to density volume. Two low density anomalies (including one new anomaly discovered) was drilled and proved to be gas-sand with low water saturation.