CEMENTING JOB EVALUATION SYSTEMS AND METHODS FOR USE WITH NOVEL CEMENT COMPOSITIONS INCLUDING RESIN CEMENT

摘要

Acoustic measurements are obtained and combined with some identification of regions that are expected or believed to be cemented. Based at least in part on this information, a processing unit derives an annular material classifier that can identify those measurements characteristic of the cemented regions (including regions cemented with a resin cement formulation), and that further applies the classifier to the measurements to generate a cement log that can be displayed to a user. Cross-plots of waveform amplitude, acoustic impedance, and the derivative of acoustic impedance, have revealed that resin cement, for example, has characteristic acoustic properties that form a small cluster within the range of expected measurements. For improved identification reliability, such clusters can be identified adaptively.

主权项

1. A cement evaluation system that comprises:
one or more logging tools that collect acoustic measurements while being conveyed through a logging region of a casing string in a cemented well; and a processing unit that obtains said measurements and receives an indication of cemented regions within the logging region, said cemented regions being cemented with a resin cement, wherein the processing unit combines said measurements with said indication to derive a classifier for annular material around the casing, wherein the processing unit applies the classifier to the measurements to generate a cement log that is displayed to a user.