Seismic-guided estimation of log properties (Part 3: A controlled study)

Abstract

In the first two parts of this series (published in the previous two issues of TLE), we discussed an alternative way of generating maps of rock or reservoir properties by using seismic attribute guidance. Normal procedure in generating such property maps (e.g., porosity, water or hydrocarbon saturation) takes the well data as control values, and uses 3-D seismic mainly for structural control. Using 3-D seismic attributes to guide the estimate of properties takes more effort, so there must be a reason that we choose to do it that way. In Part 1, we saw that property maps generated using attributes show greater detail. We also saw some theoretical considerations suggesting greater accuracy compared to maps from log data alone, but greater accuracy was not proven or demonstrated. Here we address the question Are the maps really more accurate? by reviewing the results of a controlled study.