Two small earthquakes near Blackpool in northwest England earlier this year were probably caused by hydraulic fracturing, a technique of breaking apart underground rocks to extract natural gas.
It is “highly probable” that fracking, as the process is known, at the Preese Hall-1 site caused the seismic events, Cuadrilla Resources Ltd., a U.K.-based shale explorer, said in a report published today. The combination of geological factors that led to the events were rare and the strongest possible tremor, of a magnitude of 3, would not be a risk to safety or property on the surface, the report said.
The findings may still add to concern that fracking is harmful to the environment and slow its development in the U.K. While the technology has made the U.S. the world’s largest gas producer, France has halted fracking because of concern it may pollute drinking water. Cuadrilla estimates the reserves found near Blackpool may hold enough gas to supply the U.K. with all its gas for a year and a half.
“We unequivocally accept the findings of this independent report,” said Mark Miller, chief executive officer of Cuadrilla. “We are ready to put in place the early detection system that has been proposed in the report so that we can provide additional confidence and security to the local community.”
Cuadrilla earlier this year stopped operations after two tremors that were felt on the surface. One event measured 2.3 on the Richter scale on April 1 and another on May 27 measured 1.5. Homeowners in the seaside resort of Blackpool called the police after feeling their houses shake, the British Broadcasting Corp. reported.
Protesters from Frack Off, a group protesting against shale drilling, entered one of Cuadrilla;s sites today and stopped operations, a company spokesman said.
Pressure from fluids on a stressed fault zone probably caused the events, the report said. It is unlikely that other wells in the basin will encounter similar faults, the report said.