Location:

Period:

1 Dec 2023 07:35:43 - 5 Dec 2023 00:13:27 (3 days 16 hours 37 minutes)

Volcanoes in 100km radius:

Salton Buttes(55km), Prieto, Cerro(63km)

Earthquakes:

23 swarms found nearby.

2006

S20060914.1(16.9km)

14 Sep

1 day 19 hours

38 earthquakes

S20061104.1(17.7km)

3 Nov

1 day 23 hours

33 earthquakes

S20061129.1(13.5km)

29 Nov

1 day 4 hours

34 earthquakes

2007

S20070416.1(17.3km)

15 Apr

16 days 10 hours

190 earthquakes

2009

S20091102.1(21.3km)

1 Nov

4 days 17 hours

286 earthquakes

S20091108.1(25.7km)

8 Nov

1 day 14 hours

54 earthquakes

S20091126.1(20.7km)

26 Nov

1 day 0 hours

35 earthquakes

2010

S20100404.1(26.7km)

3 Apr

55 days 14 hours

4548 earthquakes

S20100405.5(18.7km)

4 Apr

23 days 16 hours

571 earthquakes

PS20100405.1(78.7km)

4 Apr

1 hours

5 earthquakes

S20100405.2(30.0km)

4 Apr

20 days 15 hours

840 earthquakes

S20100406.1(24.1km)

5 Apr

4 days 7 hours

57 earthquakes

S20100504.1(7.7km)

3 May

2 days 2 hours

89 earthquakes

S20100517.2(17.2km)

16 May

3 days 18 hours

47 earthquakes

S20100529.1(14.1km)

28 May

83 days 1 hours

3232 earthquakes

S20100602.1(20.5km)

2 Jun

8 days 18 hours

98 earthquakes

S20100724.2(8.3km)

23 Jul

4 days 12 hours

62 earthquakes

S20101210.1(16.5km)

9 Dec

5 days 20 hours

59 earthquakes

S20101218.1(12.9km)

17 Dec

2 days 1 hours

36 earthquakes

2011

S20110409.1(20.1km)

8 Apr

2 days 21 hours

41 earthquakes

2021

S20210201.1(3.6km)

31 Jan

3 days 21 hours

68 earthquakes

S20210208.1(3.7km)

7 Feb

4 days 3 hours

49 earthquakes

2023

S20230428.1(29.2km)

28 Apr

4 days 3 hours

186 earthquakes

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

Seismic Swarm S20231202.1 Near Ocotillo, California

A notable earthquake swarm, designated S20231202.1 by SeismoSight internal classification, occurred east of Ocotillo in Imperial County, California. The sequence began at 07:35 on 1 December 2023 and concluded at 00:13 on 5 December 2023, spanning 88 hours and 37 minutes. During this period, 64 earthquakes were recorded, with the largest event reaching magnitude 4.8 at a depth of 8 km.

The swarm's temporal distribution showed the highest activity on the first day, including multiple events above magnitude 2.0. Magnitudes generally ranged from 0.5 to 4.8, and focal depths varied between 0 and 10 km, consistent with shallow crustal seismicity in the region. Such swarms typically lack a single dominant mainshock and instead feature numerous events of similar size, often linked to fluid migration or aseismic slip along faults.

Ocotillo lies within the tectonically active Salton Trough, part of the boundary between the Pacific and North American plates. The area experiences distributed deformation through a network of strike-slip and normal faults associated with the San Andreas system and the Imperial Fault. Historical seismicity includes the 1940 Imperial Valley earthquake (M7.1) and the 2010 El Mayor-Cucapah event (M7.2) in Baja California, which produced aftershocks extending into southern California.

Since 2000, 23 swarms have been documented in the broader region. Notable clusters occurred in 2010 (12 swarms) and 2006–2009, reflecting episodic activity along secondary faults east of the main plate boundary. The 2023 swarm aligns with this pattern of recurrent, low-to-moderate magnitude sequences.

These events pose minimal surface rupture risk but can indicate stress changes on nearby faults. Monitoring by regional networks continues to track potential evolution into larger sequences, though most swarms in this setting remain self-contained.

References

USGS Earthquake Hazards Program, Imperial County seismicity reports (2023 updates).
California Geological Survey, Salton Trough fault mapping.
SeismoSight internal swarm database for event parameters.