M3.9 Earthquake 8 km NE of Hermleigh, Texas — September 22, 2023
2023-09-22 20:15:58 UTC (2023-09-22) · approx. 1:15 PM UTC-7 local
Felt by 22 people across nearby locations. Maximum shaking intensity MMI 5.3 (strong).
On September 22, 2023 at 20:15 UTC, a magnitude 3.9 shallow crustal earthquake struck 8 km NE of Hermleigh, Texas, at a depth of 6.8 km and coordinates 32.6850°, -100.6890°. The earthquake was reported felt by 22 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 5.3 (strong). This earthquake was detected by 23 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 243, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 3.9 releases seismic energy equivalent to roughly 11 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 296 m — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Texas, a region characterized by a mix of natural intraplate seismicity and induced events in the Permian Basin linked to wastewater disposal. View all earthquakes in Texas.
Learn more: Magnitude scale · Aftershock sequences
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 22 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-100.6890°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.9 earthquake near Hermleigh, Texas?
The magnitude 3.9 earthquake that struck 8 km NE of Hermleigh, Texas on September 22, 2023 at 20:15 UTC had a depth of 6.8 km. It was felt by 22 people with maximum shaking intensity of MMI 5.3 (strong). For context, this was a minor earthquake typically detected only by instruments.
Where did the earthquake occur?
The earthquake epicenter was located at 32.6850°, -100.6890°, which is 8 km NE of Hermleigh, Texas. View all earthquakes in Texas.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.9 earthquakes can continue for several days and gradually diminish over time.
Has Texas had earthquakes this big before?
The largest recorded earthquake in Texas was the M5.8 Valentine earthquake of August 16, 1931. Today's magnitude 3.9 event is significantly smaller than that historical record.
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Location
Authoritative source: USGS event page (event ID: tx2023spwx). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, September 22, 2023). M3.9 Earthquake 8 km NE of Hermleigh, Texas — September 22, 2023. Retrieved December 2, 2023 from https://www.earthquaketracker.org/earthquakes/event/tx2023spwx/