The U.S. Geological Survey reports that the
number of earthquakes greater than magnitude 3 in Oklahoma is increasing
exponentially. There were 20 in 2009 and 427 through the first 10 ½ months of
2014. The Oklahoma Geological Survey (OGS) has now
documented a temporal connection between hydraulic fracturing and
nearby felt earthquakes, although more research is needed to prove a causal relationship.
Added on 04 December, 2014