Another swarm of small earthquakes is shaking up southern Valencia and northern Socorro counties.

At about 9:40 p.m., Monday, Aug. 17, a 3.1-magnitude quake was detected about nine miles west-southwest of the Pueblitos area in northern Socorro County. A second small quake, a 2.5-magnitude, was recorded around midnight, Tuesday, Aug. 18, about 14 miles west of Pueblitos, this time just north of the Valencia County line.

In June, a series of six earthquakes — the strongest of which measured magnitude 3.9 near Las Nutrias — had residents in both counties wonder just what was happening.

The small quakes and swarms are a familiar pattern to seismologists who have been studying the area for decades.

Dr. Mairi Litherland, the seismic network manager with the Albuquerque Seismological Laboratory, U.S. Geological Survey, said the swarms sit over the Socorro magma body.

A map shows the location of a magnitude 3.1 earthquake near Belen on Tuesday, Aug. 18, 2026.

“This area has been monitored for a long time, starting about 1960. The network has changed some since then, so we have the ability to detect small earthquakes people can’t feel,” Litherland said. “Those that people can feel, we’ve had the ability to detect the whole time.

“What does happen in this area near the Socorro magma body, the pattern we’re seeing, is there’s a swarm that lasts a couple of days or weeks, then it quiets down, then there’s another one. It’s a very common pattern for this body that we’ve seen happen in the historical past. So, it’s not your imagination that you didn’t feel anything a couple of years ago and now you’re feeling something, but it’s not unprecedented.”

There were a series of small earthquake swarms in the area in 1990 and 1991, but it’s been fairly quiet in recent years. She noted in seismology, it’s difficult to be absolutely certain about when and how severe earthquakes will be, but the current activity is similar to what’s happened in the past.

“We see when earthquakes happen and that helps us map faults and, in a statistical sense, understand what’s happening,” she said. “Stress is building up due to the magma body and then it releases. We can’t say when they will happen or how big, but people are correct — there are more this year than typical. In 1990, there were also a lot more than typical. It goes in cycles.”

The patterns with these swarms are something that is typical of magma bodies, Litherland said. In other locations, earthquakes are the result of the Earth’s crust moving along plates and faults.

“It’s a little different here. The cause is the magma body not plate tectonics, but it’s all related,” she said. “If you think about the typical pattern, there’s a big quake and aftershocks. With a magma body, you see several earthquakes that are relatively the same size over time.”

Scientists don’t have a perfect understanding of how magma bodies cause quakes, but they seem to be due to the fluid and other properties unique to a magma body.

In her June interview with the News-Bulletin, Litherland noted while oil and gas regions in the state have seen an uptick in human‑induced quakes, the Socorro area has a long, well‑documented natural history of seismicity.

Neither of the earthquakes felt this week were as large as the initial one in June, which topped out at a magnitude of 3.9.

“A lot of people felt it. It’s possible there will be more felt earthquakes in this swarm,” she said. “I do encourage anyone who felt the quakes to report them to the USGS Did you feel it? website. It helps us understand the impacts they are having on people.

“There is a lot of information on the website about earthquake preparedness. Historically, they have been moderate and not caused damage, but it never hurts to be prepared.”

If you think you felt an earthquake, visit earthquake.usgs.gov/data/dyfi/ to report the activity.

Home

Small earthquakes rumble southern Valencia County — again