Relating density and elastic velocities in clastics: an observation

Colin C. Potter

This preliminary work examines the relationship between density (rho), P-wave (Vp) and S-wave (Vs) velocity logs in different clastics, using Gardner's empirical relationship and investigates how well measured densities compare to it. Deviations from Gardner's equation were large and systematic and can be possibly related to other factors, such as lithology, porosity, and pore fluids. The log data is from four wells in the Blackfoot field in south central Alberta. The Upper Mannville and Glauconitic members of the Lower Cretaceous are the targets of this observation. Preliminary cross plots of different measured and calculated logs within these zones give estimates of possible empirical relationships.