US 12,006,812 B2
Method and system for sub-seismic fracture prediction
Si-Hai Zhang, Dhahran (SA)
Assigned to SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed by SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed on Apr. 23, 2020, as Appl. No. 16/856,384.
Prior Publication US 2021/0332691 A1, Oct. 28, 2021
Int. Cl. E21B 44/02 (2006.01); E21B 43/26 (2006.01); G01V 1/00 (2006.01); G01V 1/28 (2006.01)
CPC E21B 44/02 (2013.01) [E21B 43/26 (2013.01); G01V 1/003 (2013.01); G01V 1/28 (2013.01); E21B 2200/20 (2020.05); G01V 2210/00 (2013.01); G01V 2210/646 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method, comprising:
obtaining, by a logging system coupled to a drilling system, at least one well log for a first well acquired for a first stratigraphic interval of interest, wherein the at least one well log comprises first dip measurements and first lithologies;
generating, by a reservoir simulator comprising a computer processor and coupled to the logging system and the drilling system, a first plurality of dip angles for a first stratigraphic structure by comparing the first dip measurements to the first lithologies;
obtaining, by the reservoir simulator, first seismic data regarding seismic waves acquired for the first stratigraphic interval of interest,
identifying, by the reservoir simulator, the first stratigraphic structure as a first microscale fracture if:
a difference between a minimum dip angle of the first plurality of dip angles and a maximum dip angle of the first plurality of dip angles is greater than a predetermined angle threshold, and
the first stratigraphic structure has a size below a seismic wavelength of the seismic waves; and
for an identified first microscale fracture:
determining, by the reservoir simulator, a first seismic attribute that correlates the first microscale fracture to a first subset of the first seismic data,
generating, by the reservoir simulator, an attribute volume using the first seismic attribute with a seismic volume for a region of interest; and
generating, by the reservoir simulator and using the attribute volume, a fracture image of the first microscale fracture throughout the region of interest.