Three earthquakes a year in UK due to human activity
New research reveals that at least three earthquakes strike the UK every year as a result of human activity, with fracking exploration causing two small earthquakes in 2011. &nbsp;Though the earthquakes, caused by collapsing mines or fracking, are usually small, the largest ones can cause anxiety for local people and damage to fragile structures. &nbsp;Furthermore, despite seismicity falling 95% since the nation's deep coal mines closed, the UK government's determination to push ahead with shale gas exploration has increased the prospect of it increasing once again. &nbsp;
Scientists will now be able to see if fracking causes earthquakes thanks to new research at Newcastle University.

Research lead Professor Richard Davies and his team have looked at UK data going back to the 1970s to work out how many earth tremors have been caused by humans.

This is the first time "seismic activity" across the UK has been analysed. The aim is to set a national baseline for earthquakes caused by human activity ahead of any future decisions around fracking.

The first UK exploratory fracking operation at Preese Hall, Lancashire, in 2011 resulted in a 2.3 magnitude earthquake.

Two months later, a second earthquake of 1.5 magnitude was recorded and operations were suspended.

Earthquakes triggered or induced by humans are not a new concept for us here in the UK, but earthquakes related to fracking are. Understanding what the current situation is and setting a national baseline is imperative, otherwise how can we say with any confidence in the future what the impact of fracking has been nationwide? What this research shows is that in recent years, an average of at least three earthquakes a year, with local magnitudes greater than or equal to 1.5, are as a result of human activity." Professor Richard Davies

Thus far analysing the 1,769 seismic events over a forty year period that were above or equal to 1.5 in local magnitude, the minimum detectable threshold, the team of experts from Newcastle, Durham and Keele Universities showed that at least 21% were related to human activity, at least 40% were naturally-occurring and 39% were 'undefined'.