Overall Green Earthquake alert in United States on 21 May 2023 18:44 UTC

GDACS is a cooperation framework between the United Nations, the European Commission and disaster managers worldwide to improve alerts, information exchange and coordination in the first phase after major sudden-onset disasters.

M 5.63 in United States on 21 May 2023 18:44 UTC

Hazard models

Rapid Impact

Shakemap

Tsunami

Event summary

This earthquake is expected to have a low humanitarian impact based on the magnitude and the affected population and their vulnerability.

Earthquake Magnitude:	5.6M
Depth:	2.12 Km
Lat/Lon:	40.4056664 , -125.4869995
Event Date:	21 May 2023 18:44 UTC 21 May 2023 10:44 Local
Exposed Population:	Few people affected in MMI&>=III
Source:	NCAL SS nc73890906
Inserted at:	21 May 2023 18:49 UTC
INFORM Coping capacity of the alert score:	1.1 (United States)

GDACS Score

For more info on GDACS alert score click here.

	Earthquake (Shakemap)		GDACS score
NCAL SS	0		0
nc73890906	Scaled population (raster)	0
	C1 shakemap	0
	C2 shakemap	0
	Country Vulnerability	0
	INFORM_normalised	0

Maximum expected impact using different data sources.

ShakeMap is a product of the USGS Earthquake Hazards Program in conjunction with the regional seismic networks. ShakeMaps provide near-real-time maps of ground motion and shaking intensity following significant earthquakes.

Episode Timeline

ID	Date	Mag, Depth	MMI*	Population**	Delay (hh:mm)	Source
1506894	21 May 2023 18:44	5.51M, 2.12km	3.64	Few people (in 100km)	00:04	NCAL SS
1506895	21 May 2023 18:44	5.63M, 2.12km	3.83	N/A (in MMI>=VII)	00:05	NCAL SS
1506905	21 May 2023 18:44	5.54M, 10km	3.86	N/A (in MMI>=VII)	00:53	NCAL SS

The episode that generated the alert; the next major evaluations beyond 12 hours will not trigger additional alerts.

The episode that has the last updated information.

* The max MMI detected for sources having shakemaps;
** The population detected in MMI>=7 for episode with shakemap or in a 100km radius;
*** The tsunami max height.

Exposed population

The earthquake happened in United States ,of California (population 30,971,320) . The alertlevel for this event is GREEN

Intensity	Population
	no people

Shakemaps Timeline

Shake id #	episodeid	Lat/Lon	Magnitude	Depth	Max MMI	Date shake (UTC)	Delay (hh:mm)
1	1506895	-125.487/40.406	5.5	2.1	3.888	21 May 2023 18:52	00:08	(new episode)
2	1506895	-125.487/40.406	5.5	2.1	3.83	21 May 2023 19:18	00:34	(upd of #1)
3	1506905	-125.563/40.378	5.5	10	3.835	21 May 2023 19:42	00:58	(new episode)
4	1506905	-125.563/40.378	5.5	10	3.833	21 May 2023 19:54	01:10	(upd of #3)
5	1506905	-125.563/40.378	5.5	10	3.812	22 May 2023 00:49	06:05	(upd of #4)
6	1506905	-125.563/40.378	5.5	10	3.817	22 May 2023 07:41	12:57	(upd of #5)
7	1506905	-125.563/40.378	5.6	10	3.856	22 May 2023 19:41	1d 00:57	(upd of #6)

Affected Provinces

Region Province	Country	Population
California	United States	2600 people
California	United States	65000 people
California	United States	<1000 people

Affected populated places. Areas of interest

Name	Region Province	Country	City class	Population	Distance
Capetown	California	United States	Village	-	96 km
Petrolia	California	United States	Village	-	103 km
Loleta	California	United States	Village	-	110 km
Fields Landing	California	United States	Village	-	113 km
Humboldt Hill	California	United States	Village	3200 people	116 km
Fortuna	California	United States	Village	10000 people	116 km
Rohnerville	California	United States	Village	-	116 km
Honeydew	California	United States	Village	-	118 km
Scotia	California	United States	Village	-	118 km
Pine Hills	California	United States	Village	3100 people	119 km
Rio Dell	California	United States	Village	3200 people	119 km
Samoa	California	United States	Village	-	119 km
Eureka	California	United States	City	26000 people	121 km
Shively	California	United States	Village	-	130 km
Weott	California	United States	Village	-	133 km
Whitethorn	California	United States	Village	-	138 km
Briceland	California	United States	Village	-	139 km
Miranda	California	United States	Village	-	143 km
Garberville	California	United States	Village	-	148 km
Hoopa	California	United States	Village	-	170 km
Laytonville	California	United States	Village	1300 people	189 km
Covelo	California	United States	Village	1200 people	203 km

see full list

Critical infrastructure

Airports, ports, nuclear plants and hydrodams at risk, if affected, are listed below.

Airports

Name	Elevation (m)	Usage	Runway type	IFR	Runway Length (ft)	Distance
Eureka Municipal	6				0	116 km
Rohnerville	119	Civ.	Paved	Yes	4000	116 km
Shelter Cove	21				0	127 km
Garberville	166				0	147 km
Hoopa	109				0	169 km
Andy Mc Beth	13				0	176 km
Hayfork	707				0	196 km
Round Valley	437				0	201 km

Ports

Name	LOCODE	Country	Distance
Cape Mendocino		Wake Island	92 km
Fields Landing		Wake Island	113 km
Eureka	USEKA	Wake Island	118 km

Nuclear plants

Intensity	Name	Country	Reactors	Distance
	HUMBOLDT BAY	UNITED STATES	1	115 km

More information

For a full list of available products related to this event, please refer to the GDACS Resources page.

Disclaimer
While we try everything to ensure accuracy, this information is purely indicative and should not be used for any decision making without alternate sources of information.
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