Latest USGS risk maps include human-induced earthquake risk

The latest USGS earthquake risk maps for the first time show the probability of earthquakes next year in the central and eastern U.S.  The new USGS hazard model estimates where, how often and how strongly earthquakes may could occur in the central and eastern United States during calendar year 2016.  Also for the first time they include human-induced in addition to natural earthquake risk. Induced earthquakes are linked to human activities the most important of which is wastewater disposal from oil and gas production operations (wastewater from fracking).

 

According to USGS the central U.S. has experienced a dramatic increase in tremors over the past six years.

 

Average number of earthquakes of
magnitude 3 or greater per year
in central U.S.
1973-2008               24
2009-2015             318
2015                    1010
2016 (to Mar 15)   226 

 

The largest recent earthquake in the region, a magnitude 5.6 tremor, occured near Prague, Oklahoma near several active injection wells.

 

By way of history the biggest earthquake in the U.S. east of the Rockies was the 1811/1812 New Madrid earthquakes of estimated magnitude 7.6 -8.0.  This occurred near the Mississippi just south of the tip of Illinois where Missouri, Arkansas, Tennessee, and Kentucky come together.  Significant risk of major seismic activity in this area continues.