US 12,000,973 B2
Through tubing near-field sonic measurements to map outer casing annular content heterogeneities
Sandip Bose, Brookline, MA (US); Ralph D'Angelo, North Weymouth, MA (US); and Smaine Zeroug, Lexington, MA (US)
Assigned to Schlumberger Technology Corporation, Sugar Land, TX (US)
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
Filed on Apr. 20, 2022, as Appl. No. 17/659,913.
Claims priority of provisional application 63/176,947, filed on Apr. 20, 2021.
Prior Publication US 2022/0334284 A1, Oct. 20, 2022
Int. Cl. G01V 1/50 (2006.01)
CPC G01V 1/50 (2013.01) [G01V 2210/74 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method of determining well integrity, comprising:
exciting a cased hole configured with double casing with at least one sonic source, wherein the double casing comprises an inner casing and an outer casing;
acquiring signals with a plurality of receiving element arrays situated at a plurality of azimuthal sectors in a vicinity of the at least one sonic source;
processing the acquired signals with the plurality of receiving element arrays;
examining the processed signals for arrivals and determining whether the arrivals exhibit uniform or non-uniform signatures across all azimuths;
processing the acquired signals to obtain slowness-time-coherence (STC) signatures for specific arrivals;
examining the STC signatures and determining whether the specific arrivals exhibit the uniform or non-uniform signatures across all azimuths;
examining multiplicity of an STC signature of a specific arrival along a slowness range of interest; and
deriving a map based on the signatures reflecting azimuthal coverage of contents of an annular space outside of the outer casing.