The Greenback cluster is named for town of Greenback in eastern
Tennessee. The seismicity is of low magnitude and scattered over most of
eastern Tennessee, with some events over the border in western North
Carolina and northern Georgia. The largest events are a 4.3 mb event on
December 12, 2018 and a 4.1 Mw event on May 10, 2025. The seismic
network in this area expanded greatly around 2012, but earlier events in
the region are not well connected to those recorded in the past 15
years. Most events are recorded only to regional distances. All events
have depth control from near-source and local-distance readings.
