NEW HIGH SPEED TECHNIQUE FOR CALCULATING SYNTHETIC INDUCTION AND DPT LOGS.

Abstract

The advent of large-scale computers has made it possible to model the response of electromagnetic well logging tools such as the DPT (Deep Propagation Tool) and Dual Induction with extreme accuracy, even in complex environments consisting of multiple thin beds with invasion. Typical solutions that have been used to model tool response in these complicated geometries involve finite difference or finite element techniques. Even though these models can produce synthetic logs rather rapidly on large-scale vector computers such as a CRAY, their lengthy running times on the smaller computers that are available to most log analysts makes their regular use as an interpretation aid prohibitive. This new technique has already demonstrated its usefulness in several areas of interpretation, which will be illustrated in this paper.