US 11,988,793 B2
Waterflood front imaging using segmentally insulated well liners as on-demand electrodes
Hsieh Chen, Cambridge, MA (US); and Martin E. Poitzsch, Northumberland, NH (US)
Assigned to SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed by ARAMCO SERVICES COMPANY, Houston, TX (US)
Filed on Sep. 30, 2020, as Appl. No. 17/038,345.
Prior Publication US 2022/0099859 A1, Mar. 31, 2022
Int. Cl. G01V 20/00 (2024.01); E21B 43/08 (2006.01); E21B 47/002 (2012.01); E21B 47/113 (2012.01); G01V 3/26 (2006.01); G01V 3/38 (2006.01); G06F 30/20 (2020.01); G06F 111/10 (2020.01); G06F 113/08 (2020.01)
CPC G01V 20/00 (2024.01) [E21B 43/08 (2013.01); E21B 47/0025 (2020.05); E21B 47/113 (2020.05); G01V 3/26 (2013.01); G01V 3/38 (2013.01); G06F 30/20 (2020.01); E21B 2200/20 (2020.05); G06F 2111/10 (2020.01); G06F 2113/08 (2020.01)] 15 Claims
OG exemplary drawing
 
1. A method for monitoring waterfront movement in a subsurface formation, the method comprising:
using a computer processor:
performing forward modeling of at least one deep low-frequency electromagnetic survey of the waterfront movement,
determining, based on the forward modeling, locations for installing at least one electrically insulating spacer between a plurality of well liners to form at least one on-demand electromagnetic source electrode,
determining, based on the forward modeling, locations for installing at least one electrically insulating spacer between a plurality of well liners to form at least one on-demand electromagnetic receiver electrode, and
predicting, based on the forward modeling, a repeat survey time interval;
during well completion:
installing the at least one electrically insulating spacer between the plurality of well liners in a reservoir to form at least one on-demand electromagnetic source electrode, and
installing the at least one electrically insulating spacer between the plurality of well liners in a reservoir to form at least one on-demand electromagnetic receiver electrode;
electromagnetically performing waterfront surveys separated by the repeat time interval, wherein performing comprises: conveying into a well at least one production logging tool that temporarily converts the plurality of well liners into at least one on-demand electromagnetic source electrode and at least one on-demand receiver electrode, wherein temporarily converting the plurality of well liners into at least one on-demand electromagnetic source electrode comprises applying a low-frequency electrical signal,
determining spatial distribution of resistivity and spatial distribution of permittivity based on inverse modeling of the waterfront survey; and
producing, based the inverse modeling, a water saturation image.