Oklahoma Earthquakes Linked to Oil and Gas Development
Recent Surge in Earthquake Activity
Oklahoma has experienced a significant increase in earthquake activity in recent years. In 2014, the state recorded 145 earthquakes of magnitude 3.0 or greater, the highest number ever recorded. This surge in activity is due in part to wastewater injection, a process used in oil and gas production.
Wastewater Injection and Induced Seismicity
Wastewater injection involves pumping wastewater from oil and gas operations into underground wells. This high-pressure water can increase pressure in the surrounding rock, causing preexisting faults to slip and trigger earthquakes.
The United States Geological Survey (USGS) and the Oklahoma Geological Survey have found that wastewater injection has raised the risk of large earthquakes in Oklahoma. The largest earthquake ever recorded in the state, a magnitude 5.6 event in 2011, was linked to oil and gas operations.
Elevated Earthquake Activity and Future Risk
The increased earthquake activity in Oklahoma has raised concerns about the potential for future large earthquakes. The USGS estimates that the probability of a magnitude 6.0 or greater earthquake in Oklahoma has increased by a factor of six since 2008.
Oil and Gas Development in Other Regions
Oklahoma is not the only region affected by earthquakes linked to oil and gas production. Similar connections have been observed in Ohio, Texas, British Columbia, and other areas.
Mitigating the Risk
Researchers are working to develop ways to mitigate the risk of induced seismicity from wastewater injection. One approach is to reduce the amount of wastewater injected into underground wells. Another strategy is to use alternative methods of wastewater disposal, such as surface injection or recycling.
Ongoing Monitoring and Research
The USGS and other agencies continue to monitor earthquake activity in Oklahoma and other areas affected by oil and gas development. Ongoing research is also being conducted to better understand the causes and risks of induced seismicity.