Porosity and lithology estimation from elastic rock parameters

A suite of 456 rock property laboratory measurements were used in the forward sense to calibrate a velocity response model and in the inverse sense to assess model resolution. The laboratory data support an approximately linear relation between velocity and porosity in relatively pure sandstones, limestones and dolomites. To first order, velocity of a Iithologic mixture is the volume-weighted linear combination of velocities of the pure, porous end-member lithologies. This velocity response model is superior to Wyllie's time-average equation, in which solid grain properties are mixed prior to accounting for porosity.