US 11,719,840 B2
Subsurface wave slowness prediction system
Ruijia Wang, Singapore (SG); and Richard Timothy Coates, Katy, TX (US)
Assigned to Halliburton Energy Services, Inc., Houston, TX (US)
Appl. No. 16/499,955
Filed by Halliburton Energy Services, Inc., Houston, TX (US)
PCT Filed Dec. 28, 2018, PCT No. PCT/US2018/067805
§ 371(c)(1), (2) Date Oct. 1, 2019,
PCT Pub. No. WO2020/139362, PCT Pub. Date Jul. 2, 2020.
Prior Publication US 2021/0109241 A1, Apr. 15, 2021
Int. Cl. G01V 1/50 (2006.01); G01V 1/28 (2006.01); G01V 1/30 (2006.01)
CPC G01V 1/284 (2013.01) [G01V 1/288 (2013.01); G01V 1/303 (2013.01); G01V 1/50 (2013.01)] 23 Claims
OG exemplary drawing
 
1. An apparatus comprising:
a mechanical wave source;
a set of mechanical wave sensors placed in a borehole drilled into a formation, wherein the set of mechanical wave sensors provide subsurface wave measurements based on formation waves generated by the mechanical wave source;
a processor; and
a machine-readable medium having program code executable by the processor to cause the apparatus to:
acquire the subsurface wave measurements;
select a first set of tool wave measurements based on a common offset from the mechanical wave source;
generate a set of filtered subsurface wave measurements by filtering the subsurface wave measurements based on the first set of tool wave measurements;
generate a time-domain semblance map based on the set of filtered subsurface wave measurements, wherein the time-domain semblance map comprises an initial set of compression wave peaks;
determine a selected qualified compression wave peak based on a semblance value in the time-domain semblance map;
determine a compression wave slowness based on the selected qualified compression wave peak; and
perform a drilling operation based, at least in part, on the compression wave slowness.