SFL INTERPRETATION USING HIGH SPEED SYNTHETIC COMPUTER GENERATED LOGS.

The authors have developed a high speed semi-analytic technique for computing induction response in complex geometries. This model can produce an entire synthetic log in less than 10 minutes on a VAX computer. Because the differential equation describing the laterolog current source is similar in form to that of induction, they have successfully adapted this high speed technique to model laterolog and SFL response. In this paper a description is given of the model and its verification and demonstrate its utility by applying the model to SFL interpretation. With the development of this high speed model, the authors can rapidly calculate shoulder correction charts for various combinations of borehole and bed resistivities, even including invasion if necessary. Several representative cases are included.