An openhole gravel pack (OHGP) production well was experiencing a high gas/oil ratio (GOR) with production from the upper gas zone limiting that from the lower zones. An intervention solution was required which shut off the unwanted gas production from this upper zone while still enabling the oil production from the lower zones, accurately deployed in what was a highly deviated (maximum 72° inclination) extended reach (5800 metres) well.
A stackable straddle system was deployed to effectively shut off the upper zone gas production. E-Line deployment of the stackable straddle system using the PowerTrac® for conveyance and the PrecisionStroker for the upper and lower packer setting was selected as the most precise and cost effective solution. Unlike Slickline, it could be deployed in a highly deviated well. Also, it offered a lighter footprint and shorter deployment times than a Coiled Tubing option. Production data and a distributed temperature log were used to calculate the optimum straddle length and wellbore placement position.
With a total length of 70.1 metres and an isolation length of 64.8 metres, the stackable straddle system was successfully deployed, sealing off against the OHGP completion at the required position to shut off unwanted gas production. The operation was completed in just 10 runs and led to a decrease in the GOR from approximately 5,200 to 4,100 scf/STBO whilst the oil production rate increased by approximately 3,000 STB/D.