Patent ID: 9322949
Filing Date: 2016-04-26
CPC Classification: E21B,G01V

Claim Text:
1. A method of generating a formation density measurement about a cased wellbore, the cased wellbore penetrating a subterranean formation, the method comprising: positioning at least one downhole tool into the cased wellbore; pushing a caliper of the downhole tool against a casing of the cased wellbore; passing radiation from the at least one downhole tool through the casing and into the subterranean formation; measuring the radiation and casing measurements with at least one detector of the at least one downhole tool; generating an energy spectrum from the measured radiation; using the caliper, determining a casing thickness at a plurality of depths in the cased wellbore; generating at least one apparent density log based on the generated energy spectrum; determining at least one quality indicator; generating a compensated density log based on the apparent density log, the casing thickness at a plurality of depths, and the at least one quality indicator, whereby error is removed from the apparent density log to generate the compensated density log; validating the compensated density log based on the at least one quality indicator; and generating at least one photoelectric log based on at least one of the quality indicators comprising cement thickness.