Two earthquakes shook Meno, Oklahoma, within 27 minutes, the stronger a magnitude 3.6

Two earthquakes struck the same patch of northwestern Oklahoma on the evening of Nov. 3 local time, the U.S. Geological Survey reports. The first registered magnitude 3.6 at 00:48 UTC on Nov. 4, and the second, magnitude 3.2, followed at 01:15 UTC. Both were located 3 km southeast of Meno.

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In Oklahoma’s clock that meant 6:48 p.m. and 7:15 p.m. Central Standard Time, an interval of 27 minutes between shocks that were each strong enough to be felt but too small to threaten buildings.

The 27-minute gap and the two USGS solutions

The USGS catalog query for U.S. earthquakes of magnitude 3.0 and larger since Nov. 4 includes the pair. The stronger event, listed as ok2026vozb, has a magnitude of 3.57 and a depth of 6.79 km. The follow-up, ok2026vozy, measures 3.18 at 6.47 km. Rounded the way the agency presents them, those are the 3.6 and 3.2 that frame this story, and the clock times work out to 27 minutes and 13 seconds between origin times.

Both solutions use the local-magnitude method, written ml in the catalog, which is typical for small regional quakes recorded by dense nearby networks. Both carry a reviewed status, so an analyst has checked the automatic output. Depths of about 6.5 to 6.8 km place the ruptures in the shallow crust, within a few kilometers of each other.

The event page for the 3.6 and the page for the 3.2 hold the maps, uncertainty estimates and station lists. At the time of reading, the first quake had drawn 14 felt reports and the second 7, figures that tend to grow for a day or two as residents file late.

A dedicated record request for the 3.6 confirms the origin time as 00:48:30.789 UTC. Magnitudes in the 3 to 4 range are the ones residents often describe as a passing truck or a sharp jolt: dishes may rattle and hanging objects swing, yet structural damage is rare. Two such events less than half an hour apart can feel like a single prolonged disturbance to anyone indoors, which is part of why the felt-report system on each event page collects separate counts and does not merge them.

Why a smaller second shock matters to seismologists

A larger shock followed 27 minutes later by a smaller one nearby fits the textbook pattern of a mainshock and an aftershock, and it also fits a swarm, where several similar-sized events cluster without one clear leader. The USGS records do not classify the pair either way, and a three-hour query around the pair returned no other event of magnitude 3.0 or larger in the surrounding area. Smaller aftershocks below the catalog’s threshold may exist, which is why the query’s 3.0 cutoff matters when reading the count.

The ratio of the two energies is easy to work out from the scale. A step of 0.4 magnitude units, from 3.2 to 3.6, corresponds to roughly four times the energy released. Neither shock approaches the size at which unreinforced masonry or chimneys begin to crack, and the catalog records no damage field for either event.

Oklahoma’s earthquake record in USGS data

Oklahoma’s seismicity has been a research subject for more than a decade because the state’s earthquake count rose sharply in the 2010s. The USGS induced earthquakes program page says earthquakes in the central and eastern U.S. have risen sharply in recent years, and that the agency’s one-year hazard models in 2016, 2017 and 2018 flagged a high induced hazard across the Oklahoma and southern Kansas region. The same page says that when seismicity changes suddenly in a way that may be human-caused, the agency can deploy temporary networks of roughly 2 to 15 seismometers near the activity.

Nothing in the Meno records assigns a cause. A natural fault slip and an injection-related one produce waveforms that look alike at this size, and attribution normally rests on follow-up work such as relocating events and comparing them with nearby well operations. The Oklahoma Geological Survey, which maintains the state’s own catalog, was not reachable for this article, so its independent magnitudes remain unchecked.

Locations at this scale carry real uncertainty. A shallow event recorded by regional stations is usually pinned within a kilometer or two horizontally, and depth is the loosest coordinate, so the 6.79 and 6.47 km figures are best read as “a few kilometers down” rather than as exact depths. The near-identical position of the two epicenters, both labeled 3 km southeast of Meno, suggests a single source zone, although two separate small faults a short distance apart would produce the same labels.

The open question is whether more events follow. If the sequence extends beyond Nov. 4 at magnitude 3.0 or above, the USGS catalog query above would show it, and the felt-report counts on the two event pages would climb accordingly.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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