Location:

Period:

22 May 2017 13:09:02 - 10 Jun 2017 17:46:21 (19 days 4 hours 37 minutes)

Volcanoes in 100km radius:

Mono Lake Volcanic Field(43km), Mono-Inyo Craters(64km), Mammoth Mountain(83km)

Earthquakes:

220

21 swarms found nearby.

2001

S20010308.1(20.4km)

7 Mar

2 days 6 hours

47 earthquakes

2006

S20060411.2(17.7km)

10 Apr

1 day 8 hours

29 earthquakes

S20060505.1(23.9km)

5 May

1 day 14 hours

30 earthquakes

2011

S20110411.1(14.1km)

10 Apr

2 days 6 hours

104 earthquakes

S20110414.1(16.0km)

13 Apr

51 days 10 hours

3166 earthquakes

S20110629.1(14.8km)

28 Jun

10 days 3 hours

300 earthquakes

S20110704.1(16.9km)

3 Jul

3 days 20 hours

49 earthquakes

S20110715.1(15.8km)

14 Jul

2 days 14 hours

34 earthquakes

S20110817.1(13.3km)

17 Aug

1 day 17 hours

62 earthquakes

S20110927.1(13.6km)

26 Sep

1 day 17 hours

35 earthquakes

2013

S20130726.1(14.2km)

26 Jul

21 hours

29 earthquakes

2016

S20160411.1(28.6km)

10 Apr

2 days 12 hours

51 earthquakes

S20160805.1(19.4km)

4 Aug

5 days 7 hours

205 earthquakes

S20161228.1(16.8km)

28 Dec

58 days 12 hours

4521 earthquakes

2017

S20170228.1(0.7km)

27 Feb

31 days 8 hours

449 earthquakes

S20170413.1(0.8km)

13 Apr

15 days 23 hours

587 earthquakes

S20170415.1(15.6km)

15 Apr

12 hours

83 earthquakes

S20170721.1(1.8km)

21 Jul

27 days 22 hours

279 earthquakes

S20171009.1(20.5km)

8 Oct

3 days 3 hours

371 earthquakes

S20171021.1(6.2km)

20 Oct

2 days 5 hours

61 earthquakes

2018

S20180207.1(23.4km)

7 Feb

2 days 14 hours

56 earthquakes

AI-generated article — for informational and entertainment purposes only. May contain inaccuracies. Full disclaimerFound an error?

Seismic Swarm S20170523.1 Near Bridgeport, California

Seismic swarm S20170523.1 was recorded 30 km east-northeast of Bridgeport, California, in Mono County. The sequence began at 13:09 on 22 May 2017 and concluded at 17:46 on 10 June 2017, spanning 460 hours and 37 minutes. During this interval, 220 earthquakes were registered.

Analysis of the first 100 events reveals predominantly low-magnitude activity. Magnitudes ranged from 0.0 to 1.6, with the majority between 0.5 and 1.2. Depths varied from 0 km to 14 km, clustering most frequently between 6 km and 10 km. Early events on 22 May showed depths around 8–9 km and magnitudes up to 1.3. Subsequent activity through 29 May maintained similar depth distributions, with occasional shallower events near 1–3 km and isolated deeper occurrences at 11–14 km. No events exceeded magnitude 1.6 in this subset, indicating a swarm characterized by small, frequent releases rather than a dominant mainshock.

The region lies within the western Basin and Range Province, where extensional tectonics dominate. Normal faulting accommodates crustal stretching between the Sierra Nevada and the stable North American interior. This setting produces recurrent earthquake swarms driven by fluid migration and fault interactions rather than large single ruptures. Historical records document 17 swarms in the area since 1 January 2000, distributed across specific years: one in 2001, two in 2006, seven in 2011, one in 2013, three in 2016, and three in 2017. These episodes underscore persistent low-level seismicity consistent with the province’s ongoing extension.

The swarm’s shallow to mid-crustal depths align with typical brittle failure zones in the local volcanic and metamorphic basement rocks. Such sequences contribute to long-term strain release without producing surface rupture. Monitoring continues to refine understanding of swarm recurrence and potential links to broader tectonic processes in the Sierra Nevada–Basin and Range transition.

References

USGS Earthquake Hazards Program
California Geological Survey
SeismoSight internal swarm classification