Photograph: Repubblica Press
There is a link between the growth of the number of earthquakes and some techniques of extraction of hydrocarbons that involve the injection of large amounts of water and other fluids in the subsurface. According to a report, the Unites States Geological Survay, who analyzed thousands of earthquakes in 17 regions of the United States.
The risk change much area by area: in Oklahoma seismic episodes have become a hundred times more frequent in recent years.
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