US 11,927,711 B2
Enhanced-resolution sonic data processing for formation body wave slowness with full offset waveform data
Ruijia Wang, Singapore (SG); and Baichun Sun, Perth (AU)
Assigned to HALLIBURTON ENERGY SERVICES, INC., Houston, TX (US)
Appl. No. 17/601,990
Filed by HALLIBURTON ENERGY SERVICES, INC., Houston, TX (US)
PCT Filed May 21, 2019, PCT No. PCT/US2019/033210
§ 371(c)(1), (2) Date Oct. 7, 2021,
PCT Pub. No. WO2020/236153, PCT Pub. Date Nov. 26, 2020.
Prior Publication US 2022/0179118 A1, Jun. 9, 2022
Int. Cl. G01V 1/50 (2006.01); E21B 49/00 (2006.01); G01V 1/46 (2006.01); G01V 1/52 (2006.01)
CPC G01V 1/50 (2013.01) [E21B 49/00 (2013.01); G01V 1/46 (2013.01); G01V 1/52 (2013.01); E21B 2200/20 (2020.05); G01V 2210/1299 (2013.01); G01V 2210/1429 (2013.01); G01V 2210/324 (2013.01); G01V 2210/47 (2013.01); G01V 2210/614 (2013.01); G01V 2210/6222 (2013.01); G01V 2210/66 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method of determining body wave slowness values for a target formation zone, the method comprising:
selecting a target axial resolution based on the size of a receiver array;
obtaining, by an acoustic logging tool having the receiver array, a plurality of waveform data sets corresponding to a target formation zone, wherein each waveform data set is acquired at a different shot position;
reconstructing the plurality of waveform data sets to generate a plurality of subarray data sets corresponding to the target formation zone;
determining a slowness value for each subarray data set;
determining a slowness versus offset value for each subarray data set;
generating a borehole model having at least one alteration formation zone and a virgin formation zone;
generating a slowness versus offset model based at least in part on the borehole model;
optimizing the parameters in the borehole model by minimizing a 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;
extracting 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
extracting an alteration formation zone slowness from the optimized slowness versus offset model based on the slowness with the shortest offset predicted by the model.