First carbonate installation increases PI 30 times
Location: Texas, USA
On April 3rd of 2014, Fishbones Jetting was installed in a horizontal well in the Austin Chalk formation. Acid was pumped to jet the Fishbones laterals. Surface indications showed deployment of the needles and a substantial stimulation effect. This installation is a world record with 60 laterals created from a mother wellbore.
The well, located in a tight limestone formation, was shut in and was a candidate for re-stimulation. The formation near wellbore was depleted. The formation has 5% porosity and down hole temperature is 225 degF. Open hole size is 6.5in. The operator has found through previous workover campaigns that rotation is required to successfully run liners into the existing horizontal wells in the Austin Chalk.
- A 4.5” Fishbones Jetting completion with 15 ea. Fishbones subs and 3 ea. Backbone open hole anchors was planned for in the well, to be spaced out across selected targets for stimulation. Each sub contained four ea. needles with 90 degrees phasing. Two needles in each sub were equipped with a positive identification mechanism that stop the flow of fluid through the needle once it reaches full extension giving a surface pressure indication of needle extension.The Fishbones completion was run to TD as planned.
- In accordance with the operator procedures, the liner was rotated from the casing shoe to TD with 40 rpm with typical torque of 2,500 ft-lbs. The liner was rotated for more than 10 hours. The pumping operation went as planned. After pumping 875 bbls of acid, a pressure spike was seen confirming extension of needles (within 8% of estimated volume).
- The needles jetted successfully and had a strong stimulation effect. The pump pressure was steadily falling at constant rate during the pumping operation. The well’s productivity was 30 times higher after Fishbones stimulation. The IP-30 (cumulative production first 30 days) was 2.6 times higher than the IP-30 after initial completion and stimulation of the well.