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:
12km W of Delta, B.C., MX
Period:
22 Feb 2002 19:32:41 - 1 Mar 2002 15:18:06 (6 days 19 hours 45 minutes)
Volcanoes in 100km radius:
Prieto, Cerro(11km), Salton Buttes(99km)
Earthquakes:
453
M 7.0+:
M 7.2; The 2010 Sierra El Mayor, B.C., Mexico Earthquake; (4 Apr 2010) (7km from the swarm center)
23 swarms found nearby.
2000
2 Nov
2 days 22 hours
63 earthquakes
2002
S20020104.2(27.2km)
4 Jan
5 days 21 hours
156 earthquakes
2 Mar
4 days 12 hours
88 earthquakes
2005
VS20050510.1(15.8km)
9 May
9 days 8 hours
196 earthquakes
2006
S20060528.1(13.1km)
27 May
1 day 14 hours
27 earthquakes
2008
VS20080209.1(11.6km)
9 Feb
19 days 1 hours
830 earthquakes
25 Jun
21 hours
27 earthquakes
20 Nov
2 days 0 hours
35 earthquakes
2009
19 Sep
2 days 5 hours
46 earthquakes
S20091230.1(22.4km)
30 Dec
2 days 18 hours
112 earthquakes
2010
S20100405.1(14.1km)
4 Apr
48 days 21 hours
7938 earthquakes
PS20100405.1(13.4km)
4 Apr
1 hours
5 earthquakes
4 Apr
7 days 6 hours
271 earthquakes
S20100405.8(21.0km)
5 Apr
5 days 23 hours
131 earthquakes
S20100408.1(16.3km)
7 Apr
27 days 1 hours
638 earthquakes
19 Jun
13 days 17 hours
161 earthquakes
S20100724.3(20.1km)
24 Jul
9 days 17 hours
117 earthquakes
S20100816.1(22.9km)
15 Aug
5 days 9 hours
45 earthquakes
S20101211.1(17.0km)
11 Dec
2 days 18 hours
50 earthquakes
2012
S20120701.1(18.6km)
1 Jul
3 days 2 hours
77 earthquakes
2024
S20240512.1(15.9km)
12 May
2 days 10 hours
93 earthquakes
S20240605.1(20.6km)
5 Jun
13 hours
25 earthquakes
S20241009.2(27.0km)
8 Oct
22 hours
25 earthquakes
AI-generated article — for informational and entertainment purposes only. May contain inaccuracies. Full disclaimerFound an error?

Seismic Swarm S20020222.1: Analysis of Activity Near Delta, Baja California

Seismic swarm S20020222.1 occurred in a tectonically active region 12 km west of Delta, Baja California, Mexico. This area lies within the Salton Trough, a rift zone marking the transition between the Pacific and North American plates. The local geology features strike-slip faults and geothermal systems, including the nearby Cerro Prieto field, where fluid migration often influences seismicity. Shallow crustal depths predominate due to the extensional regime and high heat flow.

The swarm began at 19:32 on 22 February 2002 and concluded at 15:18 on 1 March 2002, spanning 163 hours and 45 minutes. A total of 453 earthquakes were recorded. The sequence initiated with a magnitude 5.7 event at 7 km depth, followed rapidly by smaller events. Analysis of the first 100 events reveals a mainshock-aftershock pattern with magnitudes mostly between 1.8 and 3.5. Depths clustered at 6–7 km, with isolated occurrences at 15 km and 1 km, indicating primarily shallow brittle failure.

Temporal distribution shows intense activity in the first hours, with events every few minutes initially, gradually decreasing. Magnitudes declined after the initial shock, consistent with typical swarm decay. Several events reached 3.0–3.5, but none exceeded the mainshock. Depths remained stable around 7 km for most events, suggesting a consistent source volume.

Historically, the region has experienced limited swarms since 2000, with only one prior swarm recorded in 2000. A notable strong earthquake, the magnitude 7.2 Sierra El Mayor event of 4 April 2010, occurred just 7 km from the swarm center, highlighting ongoing seismic hazard in the area.

This swarm provides insight into localized stress release along regional faults. The shallow depths and rapid succession of events align with fluid-assisted triggering common in geothermal zones. No surface rupture was associated, and activity remained confined to a small area.

References

SeismoSight internal swarm classification records
USGS earthquake catalog for regional tectonics and 2010 event details