Fracking at greater depths can lead to ten times the risk of earthquakes, study finds

Fracking operations that drill deeper into the earth can make triggering an earthquake almost ten times more likely, according to a new study.

The report, published this week in the Bulletin of the Seismological Society of America (BSSA), is based on data from more than 1,300 single well sites across Oklahoma.

The study found that in one rock layer, the likelihood that fracking triggered seismic activity increased from 5 to 50 per cent with increasingly deeper well operations, from 0.9 to 3.4 miles (1.5 to 5.5km).