Curve Alignment for Well-to-Well Log Correlation

Abstract

Abstract This paper presents a novel curve alignment program based on dynamic programming applied to well-to-well log correlation. The dynamic time warping (DTW) algorithm for data mining and signal processing is adapted to work on depth sampled well log data. Analytical tools to assist evaluation of curve alignment are provided. Our implementation can be described as automated, interactive, and constrained. Mathematical optimization - dynamic programming - provides the algorithmic, "automated" part of our solution to the well log correlation problem. "Interactive" means that the process is fast enough to be used interactively, and that it should be used iteratively, supplying visual and quantitative feedback to user identification of markers common to both wells. "Constrained" means that decisions by an educated user such as a geologist or a geophysicist, about depth ranges to which the algorithmic is applied is important, as are decisions about acceptance or rejection of particular results. The key to success has been display of pick selection mapped from posted depths in a "reference well" at depths on the "target" well, and the provision of interactive features so that the program be guided in the search for good problem solutions.