f Predicting Horizontal Velocities from Well Data

The Imperial College borehole test site, located in the north of England, consists of four boreholes which penetrate 250m of a layered sandstone-mudstone-limestone sequence. Borehole 1 has been fully cored and vertical and horizontal P- and S-wave velocities have been measured in the laboratory on a set of c.250 samples representative of the lithologies encountered. Furthermore, a large variety of log data, including geochemical log data, bas been acquired. Previous estimates of velocities from well logs have only attempted to predict velocities parallel to the boreholes. In this paper we present a model to predict horizontal P- and S-wave velocities from well data.