Seismic Swarm S20240107.1 Near Mentone, Texas: Geological Context and Event Analysis

An earthquake swarm designated S20240107.1 occurred 54 km west of Mentone, Texas, from 19:00 on 6 January 2024 to 13:40 on 14 January 2024. Over 186 hours and 39 minutes, the sequence produced 96 earthquakes. This activity aligns with patterns observed in the Delaware Basin, a subdivision of the Permian Basin where fluid injection associated with oil and gas operations has increased seismicity since the early 2000s.

The Delaware Basin features thick sedimentary sequences overlying Precambrian basement rocks. Natural faults in the region, combined with anthropogenic pressure changes from wastewater disposal, can trigger shallow seismic events typically at depths of 4–9 km. Depths recorded during this swarm ranged from 2 km to 9 km, consistent with induced seismicity mechanisms in the basin.

Magnitudes remained modest, with a peak of 3.0 on 8 January 2024 at 04:11:49 UTC. Other notable events included multiple shocks of 2.7–2.9, such as the 2.9 at 7 January 2024 10:10:20 and 16:30:40. The majority of events fell between 1.5 and 2.5, reflecting the swarm’s diffuse, low-energy character rather than a single mainshock-aftershock sequence.

Event timing showed clustering on 7–8 January, followed by a gradual decline through 14 January. Depths stayed predominantly in the 5–7 km range, with occasional shallower or deeper outliers. This distribution matches historical observations of injection-related swarms in West Texas, where seismicity often persists for days to weeks.

Since 1 January 2000, ten swarms have been recorded in the immediate area. One occurred in 2022 and nine in 2023, indicating an elevated rate of swarm activity in recent years. The 2024 swarm continues this trend and underscores the ongoing seismic response of the basin to industrial fluid management.

No damage or felt reports exceeding minor intensity were associated with these events, as expected for magnitudes below 3.0 at rural epicenters. Continued monitoring remains important given the basin’s productive hydrocarbon operations and documented link between injection volumes and earthquake rates.

References

USGS Earthquake Catalog (queried January 2024)
Texas Bureau of Economic Geology, Permian Basin seismicity reports
SeismoSight internal swarm classification S20240107.1