DashboardNewsSwarmsM 7.0+
VolcanoesSupervolcanoesRegionsGlobal
Favorites
BlogAbout
Privacy PolicyDisclaimer
Follow
Note:This page contains AI-generated content for informational and entertainment purposes only. It may contain inaccuracies. Raw event data is from USGS and EMSC. All statistics, lists, and derived information are generated by this site. Full disclaimerFound an error?
Location:
53 km WNW of Beluga, Alaska
Period:
7 Mar 2024 10:43:03 - 11 Mar 2024 15:43:40 (4 days 5 hours)
Volcanoes in 100km radius:
Spurr(3km), Hayes(42km), Redoubt(92km)
Earthquakes:
48
15 swarms found nearby.
2021
S20210614.1(15.1km)
14 Jun
2 hours
37 earthquakes
2022
2 Dec
1 day 16 hours
40 earthquakes
2024
19 Feb
1 day 7 hours
27 earthquakes
2 Mar
4 days 4 hours
89 earthquakes
25 Apr
3 days 17 hours
68 earthquakes
18 May
3 days 19 hours
80 earthquakes
7 Oct
4 days 19 hours
110 earthquakes
27 Oct
2 days 13 hours
56 earthquakes
1 Nov
3 days 22 hours
85 earthquakes
22 Nov
2 days 17 hours
49 earthquakes
VS20241130.1(11.5km)
30 Nov
53 days 4 hours
1155 earthquakes
2025
VS20250201.1(11.5km)
31 Jan
63 days 9 hours
1115 earthquakes
6 May
25 days 14 hours
387 earthquakes
S20250630.1(15.6km)
29 Jun
7 days 9 hours
78 earthquakes
VS20250717.1(14.2km)
16 Jul
9 days 3 hours
170 earthquakes
AI-generated article — for informational and entertainment purposes only. May contain inaccuracies. Full disclaimerFound an error?

Earthquake Swarm VS20240308.1: Analysis of Seismic Activity near Beluga, Alaska

An earthquake swarm designated VS20240308.1 occurred 53 km west-northwest of Beluga, Alaska, between 10:43 on 7 March 2024 and 15:43 on 11 March 2024. Over 101 hours, the swarm produced 48 earthquakes, with magnitudes ranging from -0.9 to 1.7 and focal depths between 0 km and 120 km. This event aligns with the region's established pattern of clustered seismicity within the tectonically active Cook Inlet basin.

The swarm's temporal distribution shows initial low-magnitude events on 7 March, followed by continued activity through 8–10 March, concluding on 11 March. Notable deeper events included a magnitude 1.7 earthquake at 120 km depth on 9 March and another at 115 km on 10 March, while most events clustered at shallow depths of 6–10 km. Magnitudes remained predominantly below 1.0, consistent with microseismic swarms that release strain without a dominant mainshock.

Geologically, the area lies within the Alaska-Aleutian subduction zone, where the Pacific Plate converges with the North American Plate at rates of approximately 6–7 cm per year. This setting generates frequent earthquakes through megathrust faulting, intraslab deformation, and crustal faulting. Beluga's proximity to the Cook Inlet places it near the Castle Mountain Fault and volcanic centers such as Mount Spurr, contributing to both tectonic and volcanic seismic sources. Historical records indicate elevated swarm activity in this sector, reflecting episodic fluid migration or stress transfer along subduction-related structures.

Since 2000, four swarms have been documented in the immediate region, occurring in 2021 (one swarm), 2022 (one swarm), and 2024 (two swarms). The 2024 sequence, including VS20240308.1, underscores ongoing strain accumulation along the margin. Such swarms typically exhibit similar characteristics: low magnitudes, variable depths, and durations of several days, aiding in monitoring subduction zone dynamics.

Seismic monitoring in south-central Alaska benefits from dense networks operated by regional agencies, enabling precise location and magnitude determination. Continued observation of these events supports improved hazard assessment for nearby infrastructure and communities.

References

SeismoSight internal classification data for swarm VS20240308.1
USGS Earthquake Hazards Program regional tectonic summaries
Alaska Earthquake Center historical seismicity reports