Overall Green Earthquake alert in United States on 20 Dec 2022 10:34 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 6.37 in United States on 20 Dec 2022 10:34 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:	6.4M
Depth:	16.06 Km
Lat/Lon:	40.5233345 , -124.3933334
Event Date:	20 Dec 2022 10:34 UTC 20 Dec 2022 02:34 Local
Exposed Population:	80 thousand (in MMI>=VII)
Source:	NCAL SS nc73821036
Inserted at:	20 Dec 2022 10:40 UTC
INFORM Coping capacity of the alert score:	2.2 (United States)

GDACS Score

For more info on GDACS alert score click here.

	Earthquake (Shakemap)		Tsunami		GDACS score
NCAL SS	0.9		0		0.9
nc73821036	Scaled population (raster)	3.74	Max wave alert	0.05m
	C1 shakemap	-0.59	Max wave realtime	0.05m
	C2 shakemap	0.53
	Country Vulnerability	0
	INFORM_normalised	0.65

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	Alert	Score	Date	Mag, Depth	MMI*	Population**	Tsunami risk***	Delay (hh:mm)	Source
1479670		0.2	20 Dec 2022 10:34	6.08M, 16.06km	6.81	2 thousand (in 100km)		00:04	NCAL SS
1479672		0.9	20 Dec 2022 10:34	6.37M, 16.06km	7.76	80 thousand (in MMI>=VII)	0.1m (at 00:55)	00:06	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
	75000 people
	49000 people
	15000 people

Shakemaps Timeline

Shake id #	Score	episodeid	Lat/Lon	Magnitude	Depth	Max MMI	Date shake (UTC)	Delay (hh:mm)
1	0.9	1479672	-124.423/40.525	6.4	17.9	7.177	20 Dec 2022 12:59	02:25	(new episode)
2	0.9	1479672	-124.423/40.525	6.4	17.9	7.207	20 Dec 2022 16:40	06:05	(upd of #1)
3	0.9	1479672	-124.423/40.525	6.4	17.9	7.186	20 Dec 2022 22:40	12:05	(upd of #2)
4	0.9	1479672	-124.423/40.525	6.4	17.9	7.21	21 Dec 2022 10:40	1d 00:06	(upd of #3)
5	0.9	1479672	-124.423/40.525	6.4	17.9	7.585	22 Dec 2022 22:40	2d 12:05	(upd of #4)
6	0.9	1479672	-124.423/40.525	6.4	17.9	7.611	23 Dec 2022 19:40	3d 09:05	(upd of #5)
7	0.9	1479672	-124.423/40.525	6.4	17.9	7.703	25 Dec 2022 00:51	4d 14:16	(upd of #6)
8	0.9	1479672	-124.423/40.525	6.4	17.9	7.765	28 Dec 2022 00:50	7d 14:16	(upd of #7)

Affected Provinces

Region Province	Country	Population
California	United States	14000 people
California	United States	75000 people
California	United States	12000 people
California	United States	14000 people
California	United States	99000 people
Oregon	United States	8200 people
California	United States	83000 people
Oregon	United States	2200 people

Affected populated places. Areas of interest

Name	Region Province	Country	City class	Population	Distance
Loleta	California	United States	Village	-	20 km
Fortuna	California	United States	Village	10000 people	23 km
Capetown	California	United States	Village	-	6 km
Rohnerville	California	United States	Village	-	22 km
Petrolia	California	United States	Village	-	24 km
Scotia	California	United States	Village	-	25 km
Rio Dell	California	United States	Village	3200 people	26 km
Fields Landing	California	United States	Village	-	27 km
Humboldt Hill	California	United States	Village	3200 people	28 km
Pine Hills	California	United States	Village	3100 people	31 km
Eureka	California	United States	City	26000 people	36 km
Myrtletown	California	United States	Village	4500 people	37 km
Samoa	California	United States	Village	-	37 km
Honeydew	California	United States	Village	-	39 km
Shively	California	United States	Village	-	39 km
Kneeland	California	United States	Village	-	43 km
Arcata	California	United States	City	17000 people	47 km
McKinleyville	California	United States	Village	14000 people	53 km
Korbel	California	United States	Village	-	53 km
Weott	California	United States	Village	-	46 km
Bridgeville	California	United States	Village	-	52 km
Miranda	California	United States	Village	-	58 km
Crannell	California	United States	Village	-	60 km
Briceland	California	United States	Village	-	62 km
Salyer	California	United States	Village	-	80 km
Hyampom	California	United States	Village	-	80 km
Burnt Ranch	California	United States	Village	-	84 km
Whitethorn	California	United States	Village	-	67 km
Garberville	California	United States	Village	-	69 km
Blocksburg	California	United States	Village	-	70 km
Alderpoint	California	United States	Village	-	78 km
Piercy	California	United States	Village	-	79 km
Zenia	California	United States	Village	-	84 km
Hoopa	California	United States	Village	-	85 km
Leggett	California	United States	Village	-	93 km
Island Mountain	California	United States	Village	-	94 km
Delloma	California	United States	Village	-	95 km
Ruth	California	United States	Village	-	95 km
Weitchpec	California	United States	Village	-	96 km
Denny	California	United States	Village	-	98 km
Big Bar	California	United States	Village	-	101 km
Peanut	California	United States	Village	-	104 km
Helena	California	United States	Village	-	111 km
Orick	California	United States	Village	-	90 km
Rockport	California	United States	Village	-	100 km
Cummings	California	United States	Village	-	101 km
Orleans	California	United States	Village	-	115 km
Knob	California	United States	Village	-	121 km
Laytonville	California	United States	Village	1300 people	121 km
Dedrick	California	United States	Village	-	122 km
Forks of Salmon	California	United States	Village	-	122 km
Somes Bar	California	United States	Village	-	124 km
Douglas City	California	United States	Village	-	124 km
Weaverville	California	United States	Village	3600 people	125 km
Dos Rios	California	United States	Village	-	126 km
Cecilville	California	United States	Village	-	127 km
Covelo	California	United States	Village	1200 people	127 km
Platina	California	United States	Village	-	129 km
Beegum	California	United States	Village	-	133 km
Crescent City	California	United States	Village	4000 people	137 km
Crescent City North	California	United States	Village	4000 people	139 km
Sawyers Bar	California	United States	Village	-	139 km
Fort Dick	California	United States	Village	-	151 km
Willits	California	United States	Village	5100 people	153 km
Trinity Center	California	United States	Village	-	155 km
Smith River	California	United States	Village	-	158 km
Gerber	California	United States	Village	-	195 km
Proberta	California	United States	Village	-	195 km
Weed	California	United States	Village	3000 people	198 km
McCloud	California	United States	Village	1300 people	208 km
Shingletown	California	United States	Village	2200 people	213 km
Burney	California	United States	Village	3200 people	234 km
Hat Creek	California	United States	Village	-	246 km
Westwood	California	United States	Village	2000 people	289 km
Algoma	Oregon	United States	Village	-	294 km
Greenville	California	United States	Village	1200 people	296 km
Woodland	California	United States	Village	49000 people	305 km
Fair Oaks	California	United States	Village	28000 people	341 km
Rancho Cordova	California	United States	Village	55000 people	341 km

see full list

Critical infrastructure

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

Airports

Name	IATA Code	Elevation (m)	Usage	Runway type	IFR	Runway Length (ft)	Distance
Rohnerville		119	Civ.	Paved	Yes	4000	22 km
Eureka Municipal		6				0	32 km
Murray Field	EKA	2	Civ.	Paved	Yes	3000	39 km
Kneeland		834				0	45 km
Arcata	ACV	66	Civ.	Paved	Yes	5900	56 km
Dinsmore		724				0	67 km
Hyampom		381				0	79 km
Shelter Cove		21				0	61 km
Garberville		166				0	69 km
Hoopa		109				0	84 km
Hell'er High Water		760				0	95 km
Ruth		843				0	99 km
Silver Creek Ranch		765				0	99 km
Hayfork		707				0	103 km
Andy Mc Beth		13				0	115 km
Round Valley		437				0	126 km
Lonnie Pool Field Weaverville		716				0	127 km
Jack Mcnamara Field	CEC	17	Civ.	Paved	Yes	5000	140 km
Trinity Center		728				0	152 km
Gravelly Valley		579				0	171 km
Tews Field		226				0	174 km
Lake California Air Park		187				0	186 km
Red Bluff Municipal	RBL	106	Civ.	Paved	Yes	5600	187 km
Mc Cloud Airstrip		1079				0	209 km
Double Creek Ranch		619				0	213 km
Burney Sheriff's Station		953				0	234 km
Springbrook		475				0	246 km
Fall River Mills		1013				0	256 km
Light Valley Tree Farm		725				0	258 km
Flying T Ranch		1323				0	331 km
Sunrise One		30				0	343 km

Ports

Name	LOCODE	Country	Distance
Fields Landing		Wake Island	26 km
Cape Mendocino		Wake Island	12 km
Eureka	USEKA	Wake Island	35 km
Crescent City	USCEC	Wake Island	137 km

Dams

Reservoir	Dam Name	River	Year	Distance
Ruth Lake	Robert W. Matthews	Mad River	1962	83 km
Hyatt	Hyatt Dam	Keene Creek	1921	244 km
Four Mile Lake	Four Mile Lake Dam		1916	280 km
Hennessey	Conn Creek	Conn Creek	1946	285 km

Nuclear plants

Intensity	Name	Country	Reactors	Distance
	HUMBOLDT BAY	UNITED STATES	1	29 km

More information

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

Disclaimer
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