How is hydraulic fracturing related to earthquakes and tremors?

Reports of hydraulic fracturing causing felt earthquakes are extremely rare. However, wastewater produced by wells that were hydraulic fractured can cause “induced” earthquakes when it is injected into deep wastewater wells.

Wastewater disposal wells operate for longer durations and inject much more fluid than the hydraulic fracturing operations. Wastewater injection can raise pressure levels in the rock formation over much longer periods of time and over larger areas than hydraulic fracturing does. Hence, wastewater injection is much more likely to induce earthquakes than hydraulic fracturing.

Most wastewater injection wells are not associated with felt earthquakes. A combination of many factors is necessary for injection to induce felt earthquakes.

Related Content

Filter Total Items: 13
Filter Total Items: 6
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: 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: 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.

Attribution: Natural Hazards
Date published: February 19, 2015

Coping with Earthquakes Induced by Fluid Injection

MENLO PARK, Calif.— A paper published today in Science provides a case for increasing transparency and data collection to enable strategies for mitigating the effects of human-induced earthquakes caused by wastewater injection associated with oil and gas production in the United States.

Attribution: Natural Hazards
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. 

Attribution: Earthquake Hazards
Filter Total Items: 7
USGS map displaying potential to experience damage from a natural or human-induced earthquake in 2017
February 24, 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 displaying potential to experience damage from a natural or human-induced earthquake in 2016
April 15, 2016

USGS map displaying potential to experience damage from a natural or human-induced earthquake in 2016. Chances range from less than one percent to 12 percent.

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

video thumbnail: Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
April 3, 2012

Hydraulic fracturing is the process of injecting wells with water, sand, and chemicals at very high pressure. This process creates fractures in deeply buried rocks to allow for the extraction of oil and natural gas as well as geothermal energy. USGS scientists discuss the opportunities and impact associated with hydraulic fracturing. Doug Duncan, associate coordinator for the USGS Energy Resources Program, addresses the increasing role that unconventional oil and gas resources play in the nation's petroleum endowment. USGS hydrologist Dennis Risser discusses some of the major water availability and quality challenges associated with natural gas development, with a focus on the Marcellus Shale in Pennsylvania. Bill Leith, associate coordinator the USGS Hazards Program, concludes by discussing the potential connection between disposal of waste fluids from hydraulic fracturing and earthquakes.

Research has identified 17 areas in the central and eastern United States with increased rates of induced seismicity.

Research has identified 17 areas in the central and eastern United States with increased rates of induced seismicity. Since 2000, several of these areas have experienced high levels of seismicity, with substantial increases since 2009 that continue today.

Installation of seismometers to monitor seismicity

Bryant Platt digs a hole to install seismometers at a home in southern Kansas. Seismometers are in the foreground.

Oil production and wastewater disposal

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 is completed, drilling engineers extract the fluids that are remaining in the well. Some of this recovered hydraulic fracturing fluid is used in subsequent fracking operations, while some of it is disposed of in deep wells.