US 12,292,540 B2
Method and system for detecting an object in a borehole
Thanh Nhan Nguyen, Clamart (FR); Kristina Prokopetc, Clamart (FR); Thomas Barrou, Clamart (FR); Janio Cornelio, Rio de Janeiro (BR); Josselin Kherroubi, Clamart (FR); and Kamaljeet Singh, Bucharest (RO)
Assigned to SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
Appl. No. 18/715,894
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
PCT Filed Apr. 7, 2023, PCT No. PCT/US2023/017880
§ 371(c)(1), (2) Date Jun. 3, 2024,
PCT Pub. No. WO2023/196591, PCT Pub. Date Oct. 12, 2023.
Claims priority of provisional application 63/362,606, filed on Apr. 7, 2022.
Prior Publication US 2024/0418895 A1, Dec. 19, 2024
Int. Cl. G01V 1/50 (2006.01); E21B 47/002 (2012.01); E21B 47/095 (2012.01)
CPC G01V 1/50 (2013.01) [E21B 47/0025 (2020.05); E21B 47/095 (2020.05); G01V 2210/74 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for detecting an object in a borehole, the method comprising:
acquiring, using a same ultrasonic logging tool at different passes or using multiple ultrasonic logging tools, at least two ultrasonic logs of a borehole section, wherein each of the ultrasonic logs comprises ultrasonic measurements taken (i) at one of the different passes or using one of the multiple ultrasonic logging tools, (ii) at a plurality of tool azimuths, and (iii) at a plurality of depths including a target depth, and wherein the ultrasonic measurements comprise at least one of: pulse-echo measurements or flexural measurements;
generating, at a processing system, a plurality of variable density log (VDL) images, wherein each of the plurality of VDL images maps ultrasonic waveform intensity as a function of the plurality of tool azimuths, and wherein each of the plurality of VDL images has a first resolution based on a sampling rate of the ultrasonic logging tool and a resolution of the plurality of tool azimuths;
aligning, at the processing system, the plurality of VDL images relative to time and tool azimuth;
merging, at the processing system, the aligned plurality of VDL images into a high-resolution VDL image having a second resolution higher than the first resolution, wherein merging the aligned plurality of VDL images comprises mapping a first number of pixels of each of the aligned plurality of VDL images to a second number of pixels, greater than the first number of pixels, wherein values of each of the second number of pixels correspond to average values of corresponding pixels of the aligned plurality of VDL images or to an interpolated value when there is no corresponding pixel of the aligned plurality of VDL images; and
detecting, at the processing system, an object present in the borehole based on the high-resolution VDL image, wherein the object comprises at least one of: a tool, a downhole device, a control line, or a flatpack, wherein detecting the object is based on an ultrasonic waveform intensity pattern of the object, and wherein the ultrasonic waveform intensity pattern is a function of time, the plurality of tool azimuths, and the plurality of depths including the target depth.