When do micro-seismic events add up to earthquakes ? Landslips ? Tsunamis ? Who really knows ? These are just a few questions amongst many about underground mining techniques that will probably never be properly answered. Several mini-quakes were suggested to be responsible for the shutdown of Cuadrilla’s activities in Blackpool, north west England early in 2011, and there have been unconfirmed links between tremors and fracking in the United States of America, where unconventional gas is heavily mined.
It is perhaps too easy to sow doubt about the disbenefits of exploding rock formations by pressure injection to release valuable energy gases – many legislative and public consultation hurdles have been knocked down by the merest flick of the public relations wrist of the unconventional fossil gas industry (and its academic and consultancy friends).
The potential to damage the structure of the Earth’s crust may be the least attributable and least accountable of hydraulic fracturing’s suspected disadvantages, but it could be the most significant in the long run. Science being conducted into the impact on crust stability from fracking and other well injection techniques could rule out a wide range of geoengineering on safety grounds, such as Carbon Capture and Storage proposals. If we can’t safely pump carbon dioxide underground, we should really revise our projections on emissions reductions from carbon capture.
[ Camp Frack is under canvas in Lancashire protesting about the imposition of hydraulic fracturing on the United Kingdom. ]