It was a testimony to the impact science projects have had on the shale sector that kicked off the 15th Annual SPE Hydraulic Fracturing Technology Conference and Exhibition (HFTC) held in the Houston area.
When the technical experts and executives gathered, they discussed how, after years of subsurface study, past beliefs have been dispelled and new learnings translated into multimillion- to billion-dollar business decisions.
At the conference’s plenary session, attendees learned from Devon Energy about why the oil company has become a vocal champion of refracturing and the influence it had on a recent acquisition that doubled its position in the Eagle Ford Shale.
Bakken Shale producer Hess Corp. tied more than a decade of work to its experimental wells that use fractures from other wells to produce oil, as well as its commitment to developing automated fracturing despite facing obstacles in industry collaboration.
SM Energy also showcased a double minifrac test as an example of the new experiments guiding its unconventional strategy in the Eagle Ford and Austin Chalk formations found in south Texas.
A closer look at what they had to say is here.
Betting Big on Refracturing
In SPE 212340, Devon offered fresh details on its big refracturing study in the Eagle Ford Shale—one that played into its decision to spend $1.8 billion last year on an acquisition in the south Texas play.
It involved two parent wells originally stimulated in 2013 and then refractured in January 2022. As a result, Devon reports the respective estimated ultimate recovery (EUR) from each well soared by 27% and 46%. These are wells that had been producing about 20 to 25 B/D, and according to data shared in the paper, at least one of them topped 1,000 B/D in the weeks following the refracturing.
Kourtney Brinkley described the recovery boost as a “significant step change” that helped the company realize a “need to incorporate recompletions into our development plans as we go forward.”
The drilling and completions engineer who helped lead the project for Devon reported that the operator’s wider refrac program in the play has seen incremental EUR increases as high as 75% with the average being at around 50%. The figures translate to a rate of return between 97 to 220%, which she said makes them “very economic projects.”
The project Brinkley outlined at the conference fell under the US Department of Energy’s (DOE) hydraulic fracturing test site program. With the help of federal funding, Devon was able to deploy an enviable array of diagnostic tools.
An observation lateral was drilled to monitor refracturing along with new completions on the pad. About 420 ft of core was taken from the observation well to capture some of the pad’s parent well fracture system.
The diagnostic kit included multiple fiber-optic installations, sealed wellbore pressure monitoring, downhole pressure gauges, ultrasonic imaging, and more.
With this rare suite of technologies, Devon was able to learn exactly how poor the initial parent completions were while later seeing just how effective its refrac designs ended up being.
First came the parent core-through that showed while a hydraulic fracture was present every 10 ft on average, the number of propped fractures represented just 8% of the total found.
Ultrasonic imaging aligned, showing initial completion design netted a cluster efficiency rate of just 19%.
Post-refrac, that number was increased to over 80%, which implies to Devon that there are a good degree more propped fractures today.
While pointing to vivid fiber data showing fracture formation, Brinkley said, “We were not just necessarily re-dilating a parent [fracture] network, popping it open for a little bit of time, and then watching it die—what we were making was new fractures in the ground.”
The project is considered a breakthrough by the Oklahoma City-based operator which, after entering the Eagle Ford about a decade ago, is facing the inevitable dilemma of what to do as new well locations grow scarcer with each passing year.
Aaron Ketter, vice president of Devon’s mid-continent and south Texas developments, characterized the problem as one of “how to elongate the runway,” and conveyed optimism that refracs are at least one of the answers.
“We saw that we were not depleting the wellbore as efficiently as we initially thought through this research.
