Location:

Period:

1 Jul 2012 03:25:20 - 4 Jul 2012 05:47:11 (3 days 2 hours 21 minutes)

Volcanoes in 100km radius:

Prieto, Cerro(27km)

Earthquakes:

M 7.0+:

M 7.2; The 2010 Sierra El Mayor, B.C., Mexico Earthquake; (4 Apr 2010) (12km from the swarm center)

22 swarms found nearby.

2000

S20000502.1(24.6km)

1 May

4 days 19 hours

60 earthquakes

VS20001102.1(25.8km)

2 Nov

2 days 22 hours

63 earthquakes

2001

S20011209.1(26.7km)

8 Dec

3 days 15 hours

57 earthquakes

2002

S20020222.1(18.6km)

22 Feb

6 days 19 hours

453 earthquakes

S20020303.1(14.1km)

2 Mar

4 days 12 hours

88 earthquakes

2006

S20060528.1(22.8km)

27 May

1 day 14 hours

27 earthquakes

2008

VS20080209.1(26.9km)

9 Feb

19 days 1 hours

830 earthquakes

S20080626.1(16.1km)

25 Jun

21 hours

27 earthquakes

VS20081120.1(26.6km)

20 Nov

2 days 0 hours

35 earthquakes

2009

S20090920.1(21.0km)

19 Sep

2 days 5 hours

46 earthquakes

2010

PS20100405.1(5.3km)

4 Apr

1 hours

5 earthquakes

S20100405.4(22.6km)

4 Apr

7 days 6 hours

271 earthquakes

S20100410.1(25.1km)

9 Apr

1 day 9 hours

29 earthquakes

S20100501.1(13.3km)

1 May

4 days 3 hours

63 earthquakes

S20100508.1(29.3km)

7 May

6 days 19 hours

95 earthquakes

S20100517.1(21.8km)

16 May

23 days 11 hours

365 earthquakes

S20100620.1(21.0km)

19 Jun

13 days 17 hours

161 earthquakes

S20100724.3(3.7km)

24 Jul

9 days 17 hours

117 earthquakes

S20100816.1(4.7km)

15 Aug

5 days 9 hours

45 earthquakes

S20101211.1(1.7km)

11 Dec

2 days 18 hours

50 earthquakes

2024

S20240512.1(27.4km)

12 May

2 days 10 hours

93 earthquakes

S20240605.1(29.4km)

5 Jun

13 hours

25 earthquakes

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

Seismic Swarm S20120701.1: Analysis of Activity Near Alberto Oviedo Mota, Baja California

Seismic swarm S20120701.1 occurred 11 km west of Alberto Oviedo Mota in Baja California, Mexico. The sequence began at 03:25 on 1 July 2012 and concluded at 05:47 on 4 July 2012. Over 74 hours and 21 minutes, 77 earthquakes were recorded, with magnitudes ranging from 1.5 to 4.6 and depths predominantly between 0 and 19 km.

This swarm exemplifies typical clustered seismicity in the region, where multiple events occur without a dominant mainshock. The largest events reached magnitude 4.6 at shallow depths of 2–9 km, consistent with shallow crustal faulting. Activity peaked in the first 24 hours, with 43 events on 1 July, followed by a steady decline. Smaller events clustered at depths around 9 km, suggesting a concentrated source volume along a fault segment.

The location lies within the Mexicali Valley, part of the Pacific–North American plate boundary. Here, right-lateral strike-slip motion occurs along the Cerro Prieto and Imperial faults, which form the northern extension of the Gulf of California rift system. The area experiences frequent low-to-moderate seismicity due to transtensional tectonics and geothermal activity associated with the Cerro Prieto volcanic field.

Historical data indicate 20 swarms in the region since 2000, with notable concentrations in 2000 (two events), 2008 (three), and especially 2010 (ten). The 2010 Sierra El Mayor–Cucapah earthquake (M 7.2) occurred only 12 km from the 2012 swarm center on 4 April 2010, highlighting the persistent seismic hazard along these faults. Post-2010 activity likely reflects ongoing stress adjustment within the fault network.

Such swarms provide insight into fluid migration and aseismic slip processes common in geothermal and rift settings. Depths under 10 km for most events align with brittle failure in the upper crust, while occasional deeper shocks (up to 19 km) indicate limited extension into the transition zone.

References

USGS Earthquake Catalog
Servicio Sismológico Nacional (Mexico)
SeismoSight internal swarm classification S20120701.1