Hydraulic Fracturing, known as "frac'ing" in the industry, has made another unwelcome appearance in the media, in which the process is termed "fracking", where it is reported that the procedure may cause earthquakes (http://www.independent.co.uk/news/science/small-earthquake-in-blackpool-major-shock-for-uks-energy-policy-2291597.html). Essentially, water containing a surfactant and various other chemicals is injected under high pressure into a source rock e.g. shale, causing the latter to fracture and release natural gas (principally methane). It is hoped that fracking will provide 45% of the U.S. gas by 2035, although the jury remains "out" on its safety aspects, awaiting the conclusions of studies by the University of Texas and by the Environmental Protection Agency.
In Europe, fracking is set to be adopted widely, particularly in Poland which has significant reserves of gas-shale, while in France, which is similarly well resourced, reservations over groundwater contamination by fracking are sufficiently strident that the country has vowed not to adopt the method. France indeed produces almost 80% of its electricity from nuclear power, while other EU nations rely far more on fossil fuels and for whom gas is a more important ingredient of their energy-mix, including the UK.
In the inauguration of a pilot study offshore near the famous holiday resort of Blackpool, renowned for its "sticks of rock" and big-dipper rides, in the North-West of the United Kingdom, an unexpected side-effect of fracking has been identified, namely an earthquake of magnitude 2.3 which has reinforced some disquiet as to the safety of the procedure. Commercial fracking is presently banned not only in France, but in New York and Pennsylvania states, from where there is footage available on YouTube of residents setting fire to their drinking water in consequence of the high levels of methane gas in it arising from neighbouring fracking operations.
Now it appears there may be another hazard associated with the process, which is reminiscent of the discovery made in Switzerland a couple of years back that pumping water deep into hot rocks to extract geothermal energy can also cause earthquakes. It is thought that the UK operation will be put on hold for several weeks while the British Geological Survey considers the situation, but given the potential importance of fracking as a substantial contribution to world future energy needs, it is almost certain that it will not be abandoned.