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:
14km ENE of Ridgecrest, CA
Period:
12 Feb 2020 12:31:22 - 18 Feb 2020 10:57:57 (5 days 22 hours 26 minutes)
Volcanoes in 100km radius:
None
Earthquakes:
159
M 7.0+:
M 7.1; Ridgecrest Earthquake Sequence; (6 Jul 2019) (14km from the swarm center)
39 swarms found nearby.
2013
3 May
1 day 22 hours
37 earthquakes
2015
S20150602.1(23.8km)
1 Jun
1 day 6 hours
36 earthquakes
2019
4 Jul
221 days 12 hours
22493 earthquakes
4 Jul
75 days 9 hours
8149 earthquakes
S20190708.2(21.5km)
7 Jul
4 days 17 hours
70 earthquakes
S20190712.1(16.2km)
11 Jul
16 hours
29 earthquakes
S20190812.1(18.0km)
12 Aug
3 days 6 hours
50 earthquakes
S20190819.2(29.6km)
19 Aug
1 day 7 hours
38 earthquakes
S20190825.1(19.4km)
24 Aug
3 days 7 hours
165 earthquakes
8 Sep
1 day 13 hours
47 earthquakes
S20190910.1(11.7km)
10 Sep
3 days 21 hours
145 earthquakes
1 Oct
4 days 13 hours
127 earthquakes
S20191005.1(20.7km)
5 Oct
3 days 16 hours
147 earthquakes
S20191006.1(13.2km)
5 Oct
1 day 18 hours
26 earthquakes
S20191014.1(13.1km)
13 Oct
1 day 23 hours
36 earthquakes
15 Oct
2 days 23 hours
108 earthquakes
S20191201.2(10.9km)
30 Nov
2 days 16 hours
49 earthquakes
1 Dec
9 days 6 hours
252 earthquakes
13 Dec
22 hours
27 earthquakes
15 Dec
6 days 12 hours
188 earthquakes
22 Dec
10 days 4 hours
196 earthquakes
2020
S20200101.1(25.0km)
1 Jan
7 days 0 hours
130 earthquakes
10 Jan
22 days 10 hours
422 earthquakes
22 Jan
17 hours
24 earthquakes
7 Feb
1 day 19 hours
44 earthquakes
21 Feb
5 days 20 hours
94 earthquakes
21 Mar
10 days 13 hours
140 earthquakes
14 Apr
7 days 19 hours
130 earthquakes
8 May
3 days 21 hours
69 earthquakes
25 May
1 day 7 hours
31 earthquakes
3 Jun
9 days 16 hours
525 earthquakes
S20200708.3(23.3km)
7 Jul
13 days 9 hours
239 earthquakes
27 Jul
13 days 20 hours
183 earthquakes
13 Aug
7 days 2 hours
81 earthquakes
21 Sep
5 days 2 hours
99 earthquakes
S20201113.2(27.4km)
12 Nov
13 days 17 hours
181 earthquakes
2021
S20210404.1(20.5km)
3 Apr
11 days 13 hours
124 earthquakes
2022
14 Jul
4 days 3 hours
55 earthquakes
2023
S20230503.1(23.8km)
2 May
1 day 6 hours
32 earthquakes
AI-generated article — for informational and entertainment purposes only. May contain inaccuracies. Full disclaimerFound an error?

Seismic Swarm S20200213.1: Analysis of Activity Near Ridgecrest, California

Seismic swarm S20200213.1 was recorded in the Ridgecrest region of California, beginning at 12:31 on 12 February 2020 and concluding at 10:57 on 18 February 2020. The sequence lasted 142 hours and 26 minutes, during which 159 earthquakes were detected at a location 14 km ENE of Ridgecrest. This activity occurred within the Eastern California Shear Zone, a tectonically active area characterized by northwest-trending strike-slip faults that accommodate a portion of the Pacific-North American plate boundary motion.

Analysis of the first 100 events reveals predominantly low-magnitude seismicity. Magnitudes ranged from -0.6 to 2.4, with the majority falling between 0.0 and 1.5. The largest events in this subset reached 2.3 and 2.4. Depths were shallow, concentrated between 1 km and 11 km, consistent with brittle failure in the upper crust. Temporal distribution showed clustering in the initial hours, followed by a gradual decline, typical of swarm behavior where no single mainshock dominates.

The Ridgecrest area lies near the intersection of the Garlock Fault and the Little Lake Fault Zone. These structures have produced historical seismicity, including the significant 2019 Ridgecrest Earthquake Sequence. That sequence featured a magnitude 7.1 mainshock on 6 July 2019, located 14 km from the center of swarm S20200213.1. The 2019 events highlighted the region's capacity for large earthquakes and extensive aftershock sequences.

Historical records since 2000 indicate 25 swarms in the vicinity, with notable concentrations in 2019 (19 swarms) and additional activity in 2013, 2015, and 2020. Swarm S20200213.1 represents one of four documented in 2020. Such recurrent swarms reflect ongoing strain accumulation and release along local fault networks in the Mojave Desert block.

This swarm underscores the persistent seismic hazard in the Ridgecrest area, where shallow crustal earthquakes can occur in clusters without a clear triggering mainshock. Continued monitoring supports improved understanding of fault interactions in the shear zone.

References

USGS Earthquake Catalog (historical seismicity and 2019 Ridgecrest sequence details)
SeismoSight internal swarm classification records (S20200213.1 parameters and event list)