Delta Facies Control on Production and Development Strategy for Recovery Factor Increase in Tivacuno Oil Field.

Summary Initial Tivacuno development wells found lateral facies changes into M1 and T stacked sandstone channels reservoirs (90’ & 110’ net pay thickness each, respectively), which gradually shift from cleaner sandstone in the western flank to shaly sand facies to the eastern flank of the field. The directional wells started producing 3000 bopd average with 2% water cut, which progressively ramped up to 90% BSW (6000 bwpd) after 5 years, accumulating 2000 Kbls average heavy oil production by well, which represented 11.5% of recovery factor. The dynamic reservoir model showed unflushed oil areas still to be drained. Then, a second development plan drilled high angle pilot wells to monitor the production. The LWD logging found preserved original OWC depth, gamma ray activation and resistivity slump in the middle zone of M1 reservoir, which suggested water formation intrusion by former production. Horizontal wells were placed underneath the shale layer found and close to original OWC. Their initial average oil production was 1200 bopd with high water cut 85% (7200 bwpd). However, they achieved 1300 Kbls average oil production by well. The recovery factor jumped from 13% to 37% in M1 reservoir and 21% to 32% in T reservoir.