One of the more recent scare stories circulated by environmentalists as an anti-fracking tactic, is the idea of humans causing earthquakes – a theme of a recent post. In this one the evidence comes from a geological source, at www.usgs.gov/blogs/features/usgs_top_story/man-made-earthquakes/
It picks up on the fact the number of earthquakes has increased over central and eastern USA – which is where the majority of the fracking is being done. Now, this is from a blog, and it should be borne in mind that we have entered into a period of low solar activity which has changed the way the Sun impacts on the Earth. For example, the magnetosphere around the Earth has contracted – and big CMEs have the potential of impacting on the surface of the Earth in ways they could not during the preceding warming period. We may also bear in mind that Piers Corbyn, in his solar/lunar model of climate is convinced that CMEs can cause earthquakes on the surface of the Earth – but not accepted by mainstream. A degree of scepticism is a necessity with any of these ideas coming from a suspect source – but the US Geological Survey should not be regarded as suspect although it has a strong association with CAGW alarmism (or at least its PR people are that way inclined – I wouldn't tar the geologists themselves with the same brush).
The numbers being quoted are more than a little interesting – rising from 21 a year to over 300 (above magnitude 3) which again would support a connection with fracking. It is also not too surprising that fracking can cause earthquakes as it is known that dams and reservoirs are capable of doing the same thing as well as major mining operations, and so too with the withdrawal of liquids from and into underground formations. Fracking is not unique in that sense and the connection appears to coincide with the injection of waste water into deep disposable wells (underground). These wells are purposely designed and chosen for disposal of fracking waste and one of the laid down preriquisites for fracking activity – another green idea with unforeseen consequences.