METHOD AND SYSTEM FOR CEMENT BOND EVALUATION IN HIGH ACOUSTIC VELOCITY FORMATIONS

摘要

An acoustic logging tool having an acoustic transmitter and at least one acoustic receiver longitudinally spaced from the transmitter is lowered into a borehole fluid within a tubular member having a known resonant frequency. A pulse of acoustic energy is then transmitted into the tubular member, and acoustic energy traversing the tubular member and formation is detected at the acoustic receiver. A frequency domain transformation is performed on the detected acoustic energy and a cement bond evaluation is performed by comparing transformed detected acoustic energy amplitudes within a predetermined range of the resonant frequency of the tubular member, effectively filtering out acoustic energy which traverses the formation surrounding the tubular member.