Patent ID: 11927711
Assignee: HALLIBURTON ENERGY SERVICES, INC.
Field: Measurement (Instruments)
Classification: CPC G  E | IPC E  G

Claim 11:
12. An apparatus comprising:
an acoustic logging tool having a receiver array, the acoustic logging tool configured to acquire a plurality of waveform data sets corresponding to a target formation zone, wherein each waveform data set is acquired at a different shot position;
at least one processor in communication with the acoustic logging tool, wherein the processor is coupled with a non-transitory computer-readable storage medium having stored therein instructions which, when executed by the at least one processor, causes the at least one processor to:
select a target axial resolution based on the size of a receiver array;
obtain a plurality of waveform data sets corresponding to a target formation zone, wherein each waveform data set is acquired at a different shot position;
reconstruct the plurality of waveform data sets to generate a plurality of subarray data sets corresponding to the target formation zone;
determine a slowness value for each subarray data set;
determine a slowness versus offset value for each subarray data set;
generate a borehole model having at least one alteration formation zone and a virgin formation zone;
generate a slowness versus offset model based at least in part on the borehole model;
optimize the parameters in the borehole model by minimizing the misfit between the slowness value for each subarray data set and the borehole model and the slowness versus offset model to generate an optimized borehole model and an optimized slowness versus offset model;
extract a virgin formation zone slowness from the optimized slowness versus offset model based on the slowness with the longest offset predicted by the model; and
extract an alteration formation zone slowness from the optimized slowness versus offset model based on the slowness with the shortest offset predicted by the model.