Cuadrilla Resources Ltd. said drilling, hydraulic fracturing, and flow testing of the UK’s first horizontal shale gas well indicated a rich reservoir of recoverable high-quality natural gas from the Bowland shale in northwest England.
Francis Egan, Cuadrilla chief executive officer, reported a complex fracture network was created in the shale and sand injected into the fractured stayed in place.
Crews started fracturing in Lancashire in October 2018, resuming fracturing in the UK for the first time in 7 years. Gas started to flow to the surface from Cuadrilla’s shale exploration well at the Preston New Road site in early November.
But Cuadrilla had to stop operations multiple times because microseismic events measured above a UK threshold requiring a halt to operations (OGJ Online, Dec. 12, 2018). Fracturing must be stopped if microseismic events of 0.5 or higher on the Richter scale are reported. Pressure in the well must be reduced.
Egan said the “intentionally conservative microseismic operating limit” has severely constrained the volume of sand that could be injected int the shale.
“We have only partially tested this well with just two out of the 41 stages installed along the horizontal section fractured fully as designed and less than 14% of the sand we had planned to inject to the shale rock put in place.”
Still, gas flowed at a peak rate of more than 200,000 standard cfd and a stable rate of some 100,000 scfd, he said. Cuadrilla estimates a potential initial flow rate range of 3-8 million scfd.
Previously, Ineos and Cuadrilla have suggested that the induced seismicity regulations be reviewed (OGJ Online, Feb. 4, 2019).
The UK Department for Business, Energy, and Industrial Strategy, however, denied the requests. “The government has given the industry significant support to develop while ensuring our world-leading regulations remain in place to ensure fracking happens safely and responsibly,” it said.
Contact Paula Dittrick at [email protected].