UK government probes report that fracing caused earthquakes

Nov. 3, 2011
The UK government said it will consider “carefully” a report commissioned by explorer Cuadrilla Resources that acknowledges recent earthquakes in the country were caused by hydraulic fracturing.

The UK government said it will consider “carefully” a report commissioned by explorer Cuadrilla Resources that acknowledges recent earthquakes in the country were caused by hydraulic fracturing.

“We will look at Cuadrilla’s report carefully with the assistance of our independent experts and regulators before deciding whether hydraulic fracturing operations should resume,” said UK Energy Minister Charles Hendry.

“The potential for unconventional gas is worth exploring because of the additional security of supply and economic benefits it could provide,” said Hendry. “But its development must be done in a way that carries public confidence.”

Hendry’s statement followed the issuance of a report by Cuadrilla Resources, undertaken following what the firm said was “unusual seismic activity near Poulton-le-Fylde in April and May 2011.”

Cuadrilla said the report had several main conclusions:

1. It is highly probable that the hydraulic fracturing of Cuadrilla’s Preese Hall-1 well did trigger a number of minor seismic events.

2. None of the events recorded, including one in April of 2.3 and one in May of 1.5 on the Richter scale, had any structural impact on the surface above.

3. The seismic events were due to an unusual combination of geology at the well site coupled with the pressure exerted by water injection as part of operations.

4. This combination of geological factors was extremely rare and would be unlikely to occur together again at future well sites.

5. If these factors were to combine again in the future local geology limits seismic events to around magnitude 3 on the Richter scale as a “worst-case scenario.”

6. Cuadrilla’s water injection operations take place very far below the earth’s surface which significantly reduces the likelihood of a seismic event of less than 3 on the Richter scale having any impact at all on the surface.

“We unequivocally accept the findings of this independent report and are pleased that the report concludes that there is no threat to people or property in the local area from our operations,” said Cuadrilla Chief Executive Officer Mark Miller.

“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,” Miller said.

The report was conducted by a team of European experts under Hans de Pater, professor of geotechnology at the Delft University of Technology in the Netherlands.

Cuadrilla has submitted the report to the UK’s Department of Energy and Climate Change and its advisory body, the British Geological Survey.

Contact Eric Watkins at [email protected].