photo of tanker trucks
Oilfield waste arrives by tanker truck at a wastewater disposal facility near Platteville, Colo. After removal of solids and oil, the wastewater is injected into a deep well for permanent storage underground. Photo by Bill Ellsworth, USGS.


Within the central and eastern United States, the number of earthquakes has increased dramatically over the past few years. Between the years 1973–2008, there was an average of 21 earthquakes of magnitude three and larger in the central and eastern United States. This rate jumped to an average of 99 M3+ earthquakes per year in 2009–2013, and the rate continues to rise. In 2014, alone, there were 659 M3 and larger earthquakes. Most of these earthquakes are in the magnitude 3–4 range, large enough to have been felt by many people, yet small enough to rarely cause damage. There were reports of damage from some of the larger events, including the M5.6 Prague, Oklahoma earthquake and the M5.3 Trinidad, Colorado earthquake.

This increase in earthquakes prompts two important questions:

Increasing Rate of Earthquakes Beginning in 2009

graph showing the increased rate of earthquakes since 2009
Cumulative number of earthquakes with a magnitude of 3.0 or larger in the central and eastern United States, 1970–2016. The long-term rate of approximately 29 earthquakes per year increased sharply starting around 2009.

Yes, Humans Are Causing Earthquakes

Justin Rubinstein video

USGS scientist Justin Rubinstein gives an overview on human-caused earthquakes.

Injection-Induced Seismicity

Bill Ellsworth video

USGS scientist Bill Ellsworth discusses the science behind induced earthquakes.

Special Issues on Induced Seismicity

June 2015 cover of The Leading Edge

The Leading Edge

The June issue of The Leading Edge features a special section on Injection-induced seismicity. Four USGS studies were included as part of this issue.

See also: