Two consecutive earthquakes shook Eunice, New Mexico, indicating the potential reactivation of the longstanding Alamogordo fault and the actively widening Rio Grande Rift, Daily Mail reported.
Two earthquakes struck New Mexico last Thursday, stirring residents from their routines. Occurring just five minutes apart, the seismic events registered magnitudes of 3.6 and 3.1 and hit near the town of Eunice at approximately 12:24 pm local time. The earthquakes centered less than 10 miles south of the town, directly impacting the area.
Both tremors were relatively moderate in intensity but were significant enough to rattle residents and stir concerns about the ancient faults beneath their feet. The twin quakes took place in a geologically complex region defined by the 600-mile long Rio Grande Rift, which extends from southern Colorado into north Mexico, and the 68-mile long Alamogordo fault running through central to southern New Mexico.
The Alamogordo fault, where these earthquakes occurred, was formed approximately 30 million years ago and has since been a notable structural feature in New Mexico’s geological landscape. Over millennia, such faults can accumulate stresses that occasionally release in the form of earthquakes.
Further compounding the region's seismic activity is the Rio Grande Rift. Unlike many geological rifts that are quiescent, the Rio Grande Rift is active and continues to widen by as much as two millimeters annually. This rifting contributes significantly to reshaping the earth beneath New Mexico, stretching and thinning the Earth’s crust and creating new faults and adjustment zones.
Eunice is not only a geologically active area but also a hub for oil and gas activities, prominently featuring hydraulic fracturing, or fracking. This method involves injecting high-pressure mixtures into the earth to extract oil and natural gas. While fracking itself is not a direct trigger for earthquakes, the disposal of wastewater from this process can induce tremors.
The correlation between tremors and fracking wastewater disposal raises questions about human contributions to seismic events, as industrial actions can trigger minor adjustments or swarms of activity. We must consider these factors when evaluating the region’s seismic risk profile.
It is essential to clarify that the exact cause of Thursday's quakes remains uncertain; specialists are studying whether natural crustal activities or secondary activities like wastewater disposal were influential. Regardless of the earthquakes’ origins, the events underscore the persistent potential for seismic disturbances in this region.
According to the U.S. Geological Survey (USGS), the area is susceptible to future seismic events, which could be more damaging. Precautionary advice from the USGS urges: "Damaging earthquakes can occur in the future, so remember to: Drop, Cover, and Hold on." Additionally, the USGS has warned that "More earthquakes than usual (called aftershocks) will continue to occur near the main shock."
Local populations in Eunice and nearby cities such as Hobbs and Kermit potentially felt the tremors given their proximity to the epicenter. Hobbs, with a population of around 38,400, and Kermit, home to about 6,400 people, are particularly at risk given the geological features of the area.
Eunice, with its smaller population of approximately 3,100, experienced the tremors more profoundly as they occurred at shallow depths. Shallow earthquakes often feel stronger and can have more immediate impacts on small communities.
As local authorities and scientists continue to monitor the situation, the community remains vigilant. The recent earthquakes serve as a stark reminder of the dynamic and evolving nature of Earth beneath us and the ongoing need for preparedness in the face of natural unpredictabilities.
