http://news.yahoo.com/swarm-earthquakes-rattles-rural-alabama-reason-unclear-124125320.html [Broken] It will be interesting to know the cause of increased seismic activity in what has been a seismically quiet region. The eastern US, around the Appalachian mountain chain does have small earthquakes periodically. However the earthquakes are not expected to be strong, but they can occur infrequently. Tennessee earthquake of July 27, 1977 http://www.bssaonline.org/content/69/4/1081.short Along the Mississippi River. 2.7 4km NE of Ridgely, Tennessee 2015-06-14 13:11:54 UTC 2.6 8km SE of Ridgely, Tennessee 2015-06-14 07:22:53 UTC http://pubs.usgs.gov/gip/birth/birth.pdf https://en.wikipedia.org/wiki/Appalachian_Mountains https://en.wikipedia.org/wiki/Geology_of_the_Appalachians Attached image shows locations of earthquakes in SE US from Jan 1, 1970 through today. The zoomed in image shows about 500 earthquakes. The zoomed out image shows 671 earthquakes.