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)	3.76	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
	76000 people
	49000 people
	16000 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	18000 people
California	United States	65000 people
California	United States	21000 people
California	United States	11000 people
California	United States	39000 people
Oregon	United States	24000 people
California	United States	600000 people
Oregon	United States	170000 people

Affected populated places. Areas of interest

Name	Region Province	Country	City class	Population	Distance
Rohnerville	California	United States	Village	-	22 km
Fortuna	California	United States	Village	10000 people	23 km
Fields Landing	California	United States	Village	-	27 km
Humboldt Hill	California	United States	Village	3200 people	28 km
Capetown	California	United States	Village	-	6 km
Loleta	California	United States	Village	-	20 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
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
Weott	California	United States	Village	-	46 km
Arcata	California	United States	City	17000 people	47 km
Korbel	California	United States	Village	-	53 km
Bridgeville	California	United States	Village	-	52 km
McKinleyville	California	United States	Village	14000 people	53 km
Miranda	California	United States	Village	-	58 km
Crannell	California	United States	Village	-	60 km
Briceland	California	United States	Village	-	62 km
Garberville	California	United States	Village	-	69 km
Hoopa	California	United States	Village	-	85 km
Whitethorn	California	United States	Village	-	67 km
Blocksburg	California	United States	Village	-	70 km
Alderpoint	California	United States	Village	-	78 km
Piercy	California	United States	Village	-	79 km
Salyer	California	United States	Village	-	80 km
Hyampom	California	United States	Village	-	80 km
Zenia	California	United States	Village	-	84 km
Burnt Ranch	California	United States	Village	-	84 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
Orick	California	United States	Village	-	90 km
Rockport	California	United States	Village	-	100 km
Cummings	California	United States	Village	-	101 km
Helena	California	United States	Village	-	111 km
Westport	California	United States	Village	-	112 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
Sawyers Bar	California	United States	Village	-	139 km
Ono	California	United States	Village	-	151 km
Gasquet	California	United States	Village	-	152 km
Trinity Center	California	United States	Village	-	155 km
Lamoine	California	United States	Village	-	173 km
Lakehead	California	United States	Village	-	175 km
Castella	California	United States	Village	-	188 km
Dunsmuir	California	United States	Village	1900 people	195 km
Kerby	Oregon	United States	Village	-	196 km
Mount Shasta	California	United States	Village	3600 people	196 km
Walker	California	United States	Village	-	200 km
Selma	Oregon	United States	Village	-	206 km
McCloud	California	United States	Village	1300 people	208 km
Shingletown	California	United States	Village	2200 people	213 km
Grants Pass	Oregon	United States	City	23000 people	230 km
Burney	California	United States	Village	3200 people	234 km
Hat Creek	California	United States	Village	-	246 km
Azalea	Oregon	United States	Village	-	270 km
Canyonville	Oregon	United States	Village	1300 people	283 km
Milo	Oregon	United States	Village	-	290 km
Kelseyville	California	United States	Village	2900 people	218 km
Ruch	Oregon	United States	Village	-	222 km
Ashland	Oregon	United States	City	20000 people	234 km
Medford	Oregon	United States	City	63000 people	239 km
Central Point	Oregon	United States	Village	12000 people	240 km
Sebastopol	California	United States	Village	7800 people	272 km
Novato	California	United States	Village	48000 people	311 km
Lucas Valley	California	United States	Village	12000 people	318 km
Sleepy Hollow	California	United States	Village	-	320 km
Fairfax	California	United States	Village	7300 people	321 km
San Rafael	California	United States	Village	56000 people	324 km
Green Brae	California	United States	Village	-	328 km
San Quentin	California	United States	Village	-	331 km
Corte Madera	California	United States	Village	9100 people	331 km
Mill Valley	California	United States	Village	14000 people	331 km
Strawberry	California	United States	Village	5300 people	334 km
Tamalpais Valley	California	United States	Village	-	334 km
Almonte	California	United States	Village	-	334 km
Marin City	California	United States	Village	-	337 km
Tiburon	California	United States	Village	8700 people	337 km
Sausalito	California	United States	Village	7300 people	338 km
Vine Hill	California	United States	Village	3300 people	342 km
Martinez	California	United States	Village	36000 people	342 km
Maltby	California	United States	Village	-	343 km
Pacheco	California	United States	Village	3600 people	346 km
Laguna	California	United States	Village	34000 people	346 km
Pleasant Hill	California	United States	Village	33000 people	349 km
Concord	California	United States	City	120000 people	350 km
Cowell	California	United States	Village	-	353 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
Garberville		166				0	69 km
Hoopa		109				0	84 km
Shelter Cove		21				0	61 km
Hyampom		381				0	79 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
Round Valley		437				0	126 km
Lonnie Pool Field Weaverville		716				0	127 km
Trinity Center		728				0	152 km
Mount Shasta Rep	MHS	unknown				0	196 km
Dunsmuir Muni-Mott		993				0	197 km
Backachers Ranch		445				0	208 km
Mc Cloud Airstrip		1079				0	209 km
Shingletown		1183				0	218 km
Burney Sheriff's Station		953				0	234 km
Fall River Mills		1013				0	256 km
Riverview Ranch		256				0	288 km
Myrtle Creek Municipal		189				0	289 km
Myrtle Creek Municipal		185				0	293 km
Ferndale Resort		404				0	217 km
Fly By Night		506				0	221 km
Rogue Valley Medical Center		450				0	238 km
Providence Hospital		411				0	239 km
Medford Jackson County	MFR	406	Civ.	Paved	Yes	6600	242 km
Burrill		399				0	248 km
Graywood Ranch		137				0	280 km
Commodore Center		unknown				0	336 km
Buchanan Field	CCR	7	Civ.	Paved	Yes	5000	346 km
Saxon Sycan		1521				0	375 km

Ports

Name	LOCODE	Country	Distance
Cape Mendocino		Wake Island	12 km
Fields Landing		Wake Island	26 km
Eureka	USEKA	Wake Island	35 km
Richmond (cal)	USRCH	Wake Island	335 km
Redwood City	USRWC	Wake Island	342 km

Dams

Reservoir	Dam Name	River	Year	Distance
Ruth Lake	Robert W. Matthews	Mad River	1962	83 km
Clair Engle Lake	Trinity	Trinity River	1962	141 km
Lake Siskiyou	Box Canyon	Sacramento River	1970	193 km
Galesville Reservoir	Galesville Reservoir	Cow Creek	1985	277 km
Mountain Meadows Reservoir	Indian Ole	Hamilton Creek	1924	287 km
Thompson Valley Reservoir	Thompson Valley Reservoir	Silver Creek	1922	386 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.

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