The Lagunillas 07 reservoir is located on the eastern part of Lake Maracaibo in Venezuela. The reservoir contains the Laguna formation, the Lagunillas formation and the La Rosa formation. The sands are of the Miocene age, poorly consolidated, well sorted and fine-grained with an average thickness of 86 ft. The oil had an 18 API and a viscosity of 21 cp at initial conditions. Oil production began in 1926 and more than 1,000 wells have been drilled. By December 1999, 36.7 % of the initial oil in place had been produced. Flank waterflooding, at an average water injection rate of 100,000 stb per day, was introduced for pressure maintenance purposes in 1984. Cumulative water injected was 558 million barrels by December 1999.

This paper evaluates the flank waterflooding project in the Lagunillas 07 reservoir. The net oil recovery due to the flank waterflooding is estimated. The real time water front movement is determined with a front-tracking technique that uses fluid production data. The movement shows water fingering due to reservoir heterogeneity. A good match is obtained when the water front movement is cross-correlated with the petrophysical properties of the reservoir. Finally, the impact of the flank waterflooding on recovery factor is highlighted.

The paper concludes that a net oil recovery of 17 million barrels can be attributed to the flank waterflooding from 1984 to 1999. A net oil recovery of 160 million barrels is expected if the flank waterflooding is continued until 2019. The flank waterflooding is therefore considered a success. A future development plan is proposed for the reservoir.

You can access this article if you purchase or spend a download.