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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:
21 km S of Mina, Nevada
Period:
29 Mar 2021 18:42:00 - 18 Apr 2021 10:44:33 (19 days 16 hours 2 minutes)
Volcanoes in 100km radius:
None
Earthquakes:
285
24 swarms found nearby.
2003
S20030529.1(11.4km)
29 May
4 days 7 hours
164 earthquakes
15 Nov
2 days 1 hours
52 earthquakes
2013
S20130120.1(14.1km)
19 Jan
2 days 18 hours
65 earthquakes
S20130213.1(23.6km)
12 Feb
11 days 5 hours
345 earthquakes
2020
15 May
295 days 1 hours
21711 earthquakes
S20200516.1(25.5km)
15 May
32 days 11 hours
1150 earthquakes
S20200516.2(17.6km)
15 May
22 hours
26 earthquakes
16 May
11 days 1 hours
418 earthquakes
S20200528.1(17.7km)
27 May
17 days 11 hours
384 earthquakes
S20200615.1(21.1km)
14 Jun
31 days 0 hours
472 earthquakes
S20200708.2(25.2km)
7 Jul
5 days 6 hours
63 earthquakes
S20200726.1(26.3km)
25 Jul
11 days 0 hours
125 earthquakes
19 Oct
1 day 23 hours
31 earthquakes
2 Dec
8 days 6 hours
153 earthquakes
S20201211.1(24.4km)
10 Dec
1 day 1 hours
42 earthquakes
19 Dec
7 days 21 hours
133 earthquakes
2021
S20210101.1(24.6km)
1 Jan
16 hours
24 earthquakes
S20210117.2(27.7km)
17 Jan
1 day 7 hours
25 earthquakes
4 May
16 days 21 hours
229 earthquakes
26 Sep
2 days 0 hours
31 earthquakes
30 Sep
6 days 14 hours
87 earthquakes
S20211016.1(10.5km)
15 Oct
7 days 7 hours
86 earthquakes
S20211029.1(12.3km)
28 Oct
10 days 4 hours
136 earthquakes
2022
4 Jan
6 days 14 hours
106 earthquakes
AI-generated article — for informational and entertainment purposes only. May contain inaccuracies. Full disclaimerFound an error?

Seismic Swarm S20210330.1: Analysis of Activity South of Mina, Nevada

Seismic swarm S20210330.1 was recorded 21 km south of Mina, Nevada, beginning at 18:42 UTC on 29 March 2021 and concluding at 10:44 UTC on 18 April 2021. Over 472 hours and 2 minutes, the sequence produced 285 earthquakes. This event occurred in western Nevada’s Mineral County, a region shaped by ongoing tectonic deformation.

Analysis of the first 100 events reveals predominantly low-magnitude activity. The initial event measured magnitude 2.0 at 5 km depth. Subsequent shocks remained mostly below magnitude 2.0, with depths ranging from 0 km to 16 km and clustering between 2 km and 6 km. A magnitude 4.4 earthquake at 3 km depth on 30 March 2021 at 16:04 UTC represented the largest event in this subset. Magnitudes generally declined after this peak, though several events reached 2.5–3.7 over the following days. The sequence displayed typical swarm characteristics, with events occurring in rapid succession without a single dominant mainshock.

The Mina area lies within the Walker Lane belt, a northwest-trending zone of right-lateral shear that accommodates approximately 20 percent of the relative motion between the Pacific and North American plates. This tectonic setting produces distributed faulting and frequent earthquake swarms. The local geology consists of Basin and Range extensional structures superimposed on older volcanic and sedimentary rocks. Shallow focal depths observed in the swarm align with the brittle upper crust typical of this province.

Nevada has experienced multiple earthquake swarms since 2000, with 18 documented sequences in the broader region. Prior activity near Mina included two swarms in 2003, two in 2013, twelve in 2020, and two in 2021. These episodes reflect persistent strain accumulation along regional faults.

The 2021 swarm underscores the value of continuous seismic monitoring in the western Great Basin. Real-time detection of such sequences aids in distinguishing swarm behavior from foreshock-mainshock sequences and supports improved hazard assessment for nearby communities and infrastructure.

References

SeismoSight internal swarm classification S20210330.1
USGS Earthquake Catalog (earthquake.usgs.gov)
Nevada Seismological Laboratory historical records