US 11,940,588 B2
Clay detection and quantification using downhole low frequency electromagnetic measurements
Shouxiang Ma, Dhahran (SA); Ping Zhang, Albany, CA (US); Wael Abdallah, Al-Khobar (SA); and Chengbing Liu, Al-Khobar (SA)
Assigned to SAUDI ARABIAN OIL COMPANY, Dhahran (SA); and SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US); and SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed on Jan. 31, 2022, as Appl. No. 17/588,897.
Application 17/588,897 is a continuation of application No. 16/663,636, filed on Oct. 25, 2019, granted, now 11,237,292.
Prior Publication US 2022/0155479 A1, May 19, 2022
Int. Cl. G01V 3/30 (2006.01); G01V 3/28 (2006.01); C09K 8/14 (2006.01); G01V 3/38 (2006.01)
CPC G01V 3/30 (2013.01) [G01V 3/28 (2013.01); C09K 8/145 (2013.01); G01V 3/38 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for characterizing clay content of a subsurface formation of interest, the method comprising:
i) configuring and operating a downhole logging tool to conduct a downhole electromagnetic measurement on the formation of interest at a frequency less than 5000 Hertz, wherein the downhole electromagnetic measurement is used to determine and store permittivity data that characterizes permittivity of the formation of interest at the frequency less than 5000 Hertz;
ii) extracting a parameter from the permittivity data that characterizes permittivity of the formation of interest at the frequency less than 5000 Hertz;
iii) comparing the parameter extracted from the permittivity data in ii) as an input to a computational model, wherein the computational model compares the parameter extracted from the permittivity data in ii) to measured data from at least one formation known to not have clay; and if the model determines the formation has clay;
iv) comparing, with the model, the parameter extracted from the permittivity data in ii) to measured data from at least one formation known to have clay; and
v) identifying, with the model, at least one clay type and corresponding clay volume fraction for the formation of interest.