Location:

Period:

27 Jul 2020 00:37:11 - 9 Aug 2020 20:57:25 (13 days 20 hours 20 minutes)

Volcanoes in 100km radius:

None

Earthquakes:

183

M 7.0+:

M 7.1; Ridgecrest Earthquake Sequence; (6 Jul 2019) (9km from the swarm center)

67 swarms found nearby.

2012

S20121016.1(27.4km)

15 Oct

5 days 7 hours

74 earthquakes

2013

S20130504.1(13.6km)

3 May

1 day 22 hours

37 earthquakes

2015

S20150602.1(18.1km)

1 Jun

1 day 6 hours

36 earthquakes

2016

S20160813.1(29.5km)

12 Aug

2 days 10 hours

46 earthquakes

2019

S20190704.1(7.3km)

4 Jul

221 days 12 hours

22493 earthquakes

S20190705.1(15.6km)

4 Jul

75 days 9 hours

8149 earthquakes

S20190705.2(26.8km)

4 Jul

29 days 2 hours

2446 earthquakes

S20190706.4(28.5km)

5 Jul

12 days 17 hours

712 earthquakes

S20190708.2(16.8km)

7 Jul

4 days 17 hours

70 earthquakes

S20190712.1(10.2km)

11 Jul

16 hours

29 earthquakes

S20190812.1(24.2km)

12 Aug

3 days 6 hours

50 earthquakes

S20190819.2(23.5km)

19 Aug

1 day 7 hours

38 earthquakes

S20190825.1(13.3km)

24 Aug

3 days 7 hours

165 earthquakes

S20190902.1(28.0km)

2 Sep

1 day 14 hours

76 earthquakes

S20190905.2(29.4km)

4 Sep

3 days 10 hours

79 earthquakes

S20190909.2(10.2km)

8 Sep

1 day 13 hours

47 earthquakes

S20190910.1(5.9km)

10 Sep

3 days 21 hours

145 earthquakes

S20190918.1(24.1km)

17 Sep

14 days 12 hours

471 earthquakes

S20191002.1(8.4km)

1 Oct

4 days 13 hours

127 earthquakes

S20191005.1(14.7km)

5 Oct

3 days 16 hours

147 earthquakes

S20191006.1(19.4km)

5 Oct

1 day 18 hours

26 earthquakes

S20191007.1(29.2km)

6 Oct

1 day 16 hours

48 earthquakes

S20191011.1(24.5km)

10 Oct

4 days 18 hours

165 earthquakes

S20191014.1(19.2km)

13 Oct

1 day 23 hours

36 earthquakes

S20191016.2(13.8km)

15 Oct

2 days 23 hours

108 earthquakes

S20191108.1(27.4km)

7 Nov

9 days 8 hours

234 earthquakes

S20191119.1(27.1km)

18 Nov

10 days 3 hours

223 earthquakes

S20191201.2(16.9km)

30 Nov

2 days 16 hours

49 earthquakes

S20191202.1(14.2km)

1 Dec

9 days 6 hours

252 earthquakes

S20191211.1(26.3km)

10 Dec

2 days 14 hours

78 earthquakes

S20191214.1(10.5km)

13 Dec

22 hours

27 earthquakes

S20191214.2(27.4km)

14 Dec

1 day 17 hours

43 earthquakes

S20191216.1(11.8km)

15 Dec

6 days 12 hours

188 earthquakes

S20191223.1(13.1km)

22 Dec

10 days 4 hours

196 earthquakes

2020

S20200101.1(18.7km)

1 Jan

7 days 0 hours

130 earthquakes

S20200109.2(24.8km)

8 Jan

23 hours

27 earthquakes

S20200111.1(11.1km)

10 Jan

22 days 10 hours

422 earthquakes

S20200122.3(13.0km)

22 Jan

17 hours

24 earthquakes

S20200208.1(3.7km)

7 Feb

1 day 19 hours

44 earthquakes

S20200212.1(24.8km)

11 Feb

230 days 17 hours

4310 earthquakes

S20200213.1(6.4km)

12 Feb

5 days 22 hours

159 earthquakes

S20200219.2(28.6km)

18 Feb

3 days 4 hours

87 earthquakes

S20200222.1(12.5km)

21 Feb

5 days 20 hours

94 earthquakes

S20200309.1(25.3km)

8 Mar

12 days 22 hours

242 earthquakes

S20200322.1(2.9km)

21 Mar

10 days 13 hours

140 earthquakes

S20200403.1(25.7km)

2 Apr

3 days 6 hours

67 earthquakes

S20200415.1(14.6km)

14 Apr

7 days 19 hours

130 earthquakes

S20200509.1(13.8km)

8 May

3 days 21 hours

69 earthquakes

S20200521.1(26.2km)

20 May

4 days 3 hours

97 earthquakes

S20200526.1(10.5km)

25 May

1 day 7 hours

31 earthquakes

S20200527.1(25.1km)

26 May

3 days 23 hours

82 earthquakes

S20200604.1(8.5km)

3 Jun

9 days 16 hours

525 earthquakes

S20200708.3(17.5km)

7 Jul

13 days 9 hours

239 earthquakes

S20200814.1(16.1km)

13 Aug

7 days 2 hours

81 earthquakes

S20200822.1(28.0km)

21 Aug

4 days 6 hours

66 earthquakes

S20200827.1(27.7km)

26 Aug

25 days 23 hours

356 earthquakes

S20200921.1(9.8km)

21 Sep

5 days 2 hours

99 earthquakes

S20201003.1(24.4km)

2 Oct

25 days 20 hours

320 earthquakes

S20201010.1(28.9km)

9 Oct

3 days 6 hours

59 earthquakes

S20201113.2(21.4km)

12 Nov

13 days 17 hours

181 earthquakes

2021

S20210404.1(14.4km)

3 Apr

11 days 13 hours

124 earthquakes

S20210820.2(26.9km)

19 Aug

19 days 14 hours

212 earthquakes

2022

S20220126.1(27.5km)

25 Jan

2 days 8 hours

59 earthquakes

S20220608.1(27.3km)

7 Jun

1 day 20 hours

34 earthquakes

S20220715.1(4.7km)

14 Jul

4 days 3 hours

55 earthquakes

2023

S20230503.1(17.9km)

2 May

1 day 6 hours

32 earthquakes

2024

S20240811.1(29.5km)

10 Aug

5 days 16 hours

78 earthquakes

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

Seismic Swarm S20200727.1 Near Searles Valley, California

Seismic swarm S20200727.1 occurred 14 km SSW of Searles Valley in California. The sequence began at 00:37 on 27 July 2020 and concluded at 20:57 on 9 August 2020, spanning 332 hours and 20 minutes. During this period, 183 earthquakes were recorded.

Analysis of the first 100 events reveals predominantly low-magnitude activity. Magnitudes ranged from -0.1 to 2.1, with the majority below 1.5. Depths were shallow, concentrated between 0 and 12 km, consistent with crustal faulting in the region. Early events on 27 July included a 2.1 magnitude quake at 4 km depth shortly after initiation, followed by numerous smaller tremors. Activity persisted with intermittent peaks, such as a 2.0 magnitude event on 1 August at 10 km depth. The distribution indicates a typical swarm pattern of clustered, low-energy releases rather than a mainshock-aftershock sequence.

The Searles Valley area lies within the Eastern California Shear Zone, a tectonically active region characterized by northwest-trending right-lateral strike-slip faults. This zone accommodates a portion of the Pacific-North American plate motion and has produced significant historical seismicity. The 2019 Ridgecrest earthquake sequence, featuring a magnitude 7.1 mainshock on 6 July located 9 km from the swarm center, highlighted the area's potential for complex multifault ruptures on previously unmapped structures.

Since 1 January 2000, the region has experienced 53 seismic swarms. Notable years include 2019 with 30 swarms and 2020 with 19, reflecting elevated activity following the Ridgecrest events. Earlier occurrences were recorded in 2012, 2013, 2015, and 2016. These swarms underscore the diffuse nature of deformation in the shear zone, where fluid migration and stress transfer along fault networks often trigger prolonged earthquake clusters.

The swarm's timing and location suggest possible triggering influences from the 2019 Ridgecrest sequence, which altered regional stress fields. Shallow focal depths align with brittle failure in the upper crust, typical of the Mojave Desert's extensional and strike-slip regime.

References

USGS Earthquake Catalog
California Geological Survey Regional Fault Maps
SeismoSight Internal Swarm Database