Oklahoma has had a surge of earthquakes since 2009. Are they due to fracking?

Beginning in 2009, Oklahoma experienced a surge in seismicity. This surge was so large that its rate of magnitude 3 and larger earthquakes exceeded California’s from 2014 through 2017.

bar graph

Bar graph showing the number of M3+ Earthquakes in Oklahoma vs California from 1990 to 2019. California earthquake counts are shown as a blue bar and Oklahoma earthquake counts are shown as a red bar. (Public domain.)

While these earthquakes have been induced by oil and gas related process, few of these earthquakes were induced by fracking. The largest earthquake known to be induced by hydraulic fracturing in Oklahoma was a M3.6 earthquakes in 2019. The largest known fracking induced earthquake in the United States was a M4.0 earthquake that occurred in Texas in 2018. The majority of earthquakes in Oklahoma are caused by the industrial practice​ known as "wastewater disposal". Wastewater disposal is a ​separate ​process in which fluid waste from oil and gas production is injected deep underground far below ground water or drinking water aquifers. In Oklahoma over 90% of the wastewater that is injected is a byproduct of oil extraction process and not waste frack fluid.

Learn more: USGS Induced Earthquakes

Related Content

Filter Total Items: 7

How large are the earthquakes induced by fluid injection?

The largest earthquake induced by fluid injection that has been documented in the scientific literature was a magnitude 5.8 earthquake on September 23, 2016 in central Oklahoma. Four magnitude 5+ earthquakes have occurred in Oklahoma, three of which occurred in 2016. In 2011, a magnitude 5.3 earthquake was induced by fluid injection in the Raton...

Are earthquakes induced by fluid-injection activities always located close to the point of injection?

No. Given enough time, the pressure increase created by injection can migrate substantial horizontal and vertical distances from the injection location. Induced earthquakes can occur 10 or more miles from injection wells. Induced earthquakes can also occur a few miles below injection wells. Learn more: USGS Induced Earthquakes

Is there any possibility that a wastewater injection activity could interact with a nearby fault to trigger a major earthquake that causes extensive damage over a broad region?

So far, there is no documented example linking injection operations to triggering of major earthquakes. However, we cannot eliminate this possibility. Other human activities--for example oil production in Uzbekistan--have induced M7+ earthquakes. Learn more: USGS Induced Earthquakes

Does the production of oil and gas from shales cause earthquakes? If so, how are the earthquakes related to these operations?

To produce oil and gas from shale formations, it is necessary to increase the interconnectedness of the pore space (permeability) of the shale so that the gas can flow through the rock mass and be extracted through production wells. This is usually done by hydraulic fracturing ("fracking"). Fracking intentionally causes small earthquakes (...

How does the injection of fluid at depth cause earthquakes?

The fluid that is injected at depth is sometimes hydraulically connected to faults. When this happens, fluid pressures increase within the fault, counteracting the frictional forces on faults. This makes earthquakes more likely to occur on them. An analog to this system is an air hockey table. When an air hockey table is off, the puck does not...

Is it possible to anticipate whether a planned wastewater disposal activity will trigger earthquakes that are large enough to be of concern?

Currently, there are no methods available to do this in a definitive sense. We have developed methods that use injection information to help us determine whether injection activities might cause induced earthquakes and rule out other injection activities that are unlikely to induce earthquakes, but we cannot say either with certainty. There are a...

Do all wastewater disposal wells induce earthquakes?

No. Of more than 150,000 Class II injection wells in the United States, roughly 40,000 are waste fluid disposal wells for oil and gas operations. Only a small fraction of these disposal wells have induced earthquakes that are large enough to be of concern to the public. Learn more: USGS Induced Earthquakes EPA's Underground Injection Control (UIC...
Filter Total Items: 9
Date published: October 24, 2016

Wastewater Disposal Likely Induced February 2016 Magnitude 5.1 Oklahoma Earthquake

Distant wastewater disposal wells likely induced the third largest earthquake in recent Oklahoma record, the Feb. 13, 2016, magnitude 5.1 event roughly 32 kilometers northwest of Fairview, Oklahoma. These findings from the U.S. Geological Survey are available in the online edition of Geophysical Research Letters.

Date published: September 3, 2016

Magnitude 5.8 Earthquake in Oklahoma

A magnitude 5.8 earthquake struck in Oklahoma on September 3, 2016 at 12:02:44 UTC (7:02 am local time). 

Date published: March 28, 2016

EarthWord – Induced Seismicity

The occurrence or frequency of earthquakes for which the origin is attributable to human activities.

Date published: March 28, 2016

Induced Earthquakes Raise Chances of Damaging Shaking in 2016

For the first time, new USGS maps identify the potential for ground shaking from both human-induced and natural earthquakes in 2016.

Date published: February 13, 2016

Magnitude 5.1 Earthquake in Oklahoma

A magnitude 5.1 earthquake struck in Oklahoma on February 13, 2016 at 11:07:06 am local time.

Date published: October 26, 2015

A Century of Induced Earthquakes in Oklahoma?

The rate of earthquakes has increased sharply since 2009 in the central and eastern United States, with growing evidence confirming that these earthquakes are primarily caused by human activity, namely the injection of wastewater in deep disposal wells.

Date published: March 6, 2014

2011 Oklahoma Induced Earthquake May Have Triggered Larger Quake

 In a new study involving researchers at the U.S. Geological Survey, scientists observed that a human-induced magnitude 5.0 earthquake near Prague, Oklahoma in November 2011 may have triggered the larger M5.7 earthquake less than a day later. 

Date published: October 22, 2013

Earthquake Swarm Continues in Central Oklahoma

Since January 2009, more than 200 magnitude 3.0 or greater earthquakes have rattled Central Oklahoma, marking a significant rise in the frequency of these seismic events.  

Filter Total Items: 12
May 31, 2018

PubTalk 5/2018 — Yes Humans really are causing induced earthquakes

Title: Yes, Humans Really Are Causing Earthquakes! How Energy Industry Practices are Causing Earthquakes in America's Heartland

  • In every year since 2014, Oklahoma has had more earthquakes than California.
  • Oil and gas operations are "inducing" these earthquakes.
  • The earthquake rate has dropped by more than 50 percent due to changes in industry
Attribution:
USGS map displaying potential to experience damage from a natural or human-induced earthquake in 2017
February 24, 2017

USGS Forecast for Damage from Natural and Induced Earthquakes in 2017

USGS map displaying potential to experience damage from a natural or human-induced earthquake in 2017. Chances range from less than one percent to 12 percent.

USGS map showing the location of earthquakes greater than or equal to magnitude 4.0 in Oklahoma and the Raton Basin in 2016
February 24, 2017

Potentially Damaging 2016 Earthquakes in Oklahoma and the Raton Basin

USGS map showing the location of earthquakes greater than or equal to magnitude 4.0 in Oklahoma and the Raton Basin in 2016.

Damage to buildings in Cushing, Oklahoma from the magnitude 5.0 earthquake on November 6, 2016
February 24, 2017

Damage in Cushing, Oklahoma from the Magnitude 5.0 Earthquake in 2016

Damage to buildings in Cushing, Oklahoma from the magnitude 5.0 earthquake on November 6, 2016. Unreinforced brick and stone masonry buildings and facades are vulnerable to strong shaking. Photograph credit: Dolan Paris, USGS

Damage to buildings in Cushing, Oklahoma from the magnitude 5.0 earthquake in 2016
February 24, 2017

Damage in Cushing, Oklahoma from the Magnitude 5.0 Earthquake in 2016

Damage to buildings in Cushing, Oklahoma from the magnitude 5.0 earthquake on November 6, 2016. Unreinforced brick and stone masonry buildings and facades are vulnerable to strong shaking. Photograph credit: Dolan Paris, USGS

House damage in central Oklahoma from a magnitude 5.6 earthquake in 2011
February 23, 2017

Damage in central Oklahoma from a magnitude 5.6 earthquake in 2011

House damage in central Oklahoma from the magnitude 5.6 earthquake on Nov. 6, 2011. Research conducted by USGS geophysicist Elizabeth Cochran and her university-based colleagues suggests that this earthquake was induced by injection into deep disposal wells in the Wilzetta North field. Credit: Brian Sherrod, USGS

Population Exposed to Potentially Damaging Earthquake Groundshaking
October 11, 2016

Population Exposed to Potentially Damaging Earthquake Groundshaking

USGS map showing (1) the locations of major populations and (2) the intensity of potential earthquake ground shaking that has a 2% chance of occurring in 50 years.

Map showing 21 areas of observed rapid changes in seismicity related to wasterwater injection.
April 15, 2016

Wastewater observed seismicity map (2016)

USGS map displaying 21 areas where scientists have observed rapid changes in seismicity that have been associated with wastewater injection. The map also shows earthquakes—both natural and induced—recorded from 1980 to 2015 in the central and eastern U.S. with a magnitude greater than or equal to 2.5.

Oil production and wastewater disposal

Wastewater injection

Most wastewater currently disposed of across the nation is generated and produced in the process of oil and gas extraction. Saltwater is produced as a byproduct during the extraction process. This wastewater is found at nearly every oil and gas extraction well.

The other main constituent of wastewater is leftover hydraulic fracturing fluid. Once hydraulic fracturing

...