On Sunday Evening an M4.3 Earthquake struck in the North Greenland Sea near Seattle (The United States).

Written by Earthquakelist.org on October 9th, 2023. Last updated December 7th, 2023.

A Magnitude 4.3 earthquake struck in the North Greenland Sea 34 miles from Seattle, The United States in the evening of Sunday October 8th, 2023. The earthquake struck near a very densely populated region. The USGS has indicated there is a potential risk at tsunami's following this earthquake. Another country near the epicenter is Canada.

Earthquake Summary

This earthquake hit under water in the North Greenland Sea, right off the coast of The United States (2 km offshore), 34 miles north-northwest of Seattle in Washington. The center of this earthquake had a quite shallow depth of 35 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Oct 8, 2023 07:21PM (Los Angeles Time) - Oct 9, 2023 02:21 Universal Time.
Location:	34 mi NNW of Seattle, Washington, The United States. Coordinates 48°1'58"N 122°42'23"W.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 4.3 Detected by 114 stations. Maximum Error Range ±0.2 .
Depth:	35 mi (57 km) A quite shallow depth.
Max. Intensity:	IV Light On the Modified Mercalli Scale.
Tsunami Risk:	Potential tsunami risk The USGS has indicated there is a potential risk at tsunami's following this earthquake. Always stay cautious - More info here.

Potential tsunami risk

DISCLAIMER: We strongly suggest to closely monitor advice from local authorities with regards to tsunami risks. Our analysis is based on automatically collected data from external sources, and these might contain mistakes. In addition, earthquakes can cause landslides that may lead to a tsunami, or be a followed by another, potentially stonger, earthquake.

There is a potential tsunami risk in the aftermath of this earthquake, immediately evacuate to higher grounds away from coastal areas and monitor advice from local authorities. The US Geographic Survey organization has indicated a potential risk for tsunami's following this earthquake.

Tsunami Risk Factors

Factor	Under Sea?	MAG-6.5 or stronger?	Shallow depth?
Explanation	Almost all tsunami's are caused by earthquakes with their epicenter under sea or very near the sea. However stay cautious in coastal areas as earthquakes on land may cause landslides into sea, potentially still causing a local tsunami.	Under MAG 6.5: Very unlikely to cause a tsunami. MAG 6.5 to 7.5: Destructive tsunami's do occur, but are uncommon. Likely to observe small sea level changes. MAG 7.6+: Earthquakes with these magnitudes might produce destructive tsunami's.	Most destructive tsunami's are caused by shallow earthquakes with a depth between 0 and 100km under the surface of the earth. Deeper tsunami's are unlikely to displace to ocean floor.
This Earthquake	This earthquake appears to have struck under the sea.	Not this earthquake. This earthquake had a magnitude of 4.3. Earthquakes of this strength are unlikely to trigger a tsunami.	This earthquake occurred at a depth of of 35 mi (57 km). Earthquakes this shallow could trigger a tsunami.

Minimal impact predicted

Based on scientific estimates by the US Geographic Survey (USGS), the risk of high fatalities for this earthquake is classified at level GREEN (low). They expect an 65% likelyhood of between 0 and 1 fatalities, and a 96% chance that the number of fatalities falls no higher than 10.

The USGS classifies the economic impact of this earthquake at level GREEN (low). They expect an 65% likelyhood of between 0 and 1 million US Dollars in economic damage and impact, and a 96% chance that the economic impact of this earthquake falls no higher than 10 million USD.

Roughly 9 million people exposed to shaking

This earthquake may have been felt by around 9 million people. That is the expected population size of the area exposed to a level of shaking of II or higher on the Modified Mercalli scale according to the USGS.

The highest earthquake impact level for this earthquake is IV, which corresponds with light shaking and likely no damage. Roughly 2,120 people are expected to be exposed to this level. Intensity level II was experienced by the majority of people (around 7.1 million). In their region, very weak shaking and no damage can be expected. All exposure to shaking was within the borders of Canada .

People	MMI Level	Shaking	Damage
397,300	I	Not noticable	None
7,090,000	II	Very weak	None
2,126,000	III	Weak	Probably none
2,120	IV	Light	Likely none
0	V	Moderate	Very light
0	VI	Strong	Light
0	VII	Very Strong	Moderate
0	VIII	Severe	Moderate to heavy
0	IX	Violent	Heavy
0	X	Extreme	Very heavy

Nearby towns and cities

2 countries can be found within 300km of the epicenter of this earthquake: The United States and Canada .

Located 18 miles (29 km) south of the epicenter of this earthquake, Oak Harbor (Washington, The United States) is the nearest significant population center. The intensity of shaking and damage in Oak Harbor is estimated to be around level III on the Modified Mercalli Intensity scale (weak shaking, probably no damage).

Multiple large cities are in proximity of today's earthquake. Seattle is located 34 mi to the south-southeast and experienced an intensity of III (weak shaking, probably no damage). Victoria is located 66 km to the northwest and experienced an intensity of III (weak shaking, probably no damage). Vancouver is located 139 km to the north-northwest (intensity unknown, possibly low).

The table below provides an overview of all places in proximity of today's earthquake. Where available, the estimated intensity on the Modified Mercalli Intensity Scale in each place is included. Places where this information is omitted likely experienced little impact.

Overview of nearby places

Cities and Towns around the epicenter of this earthquake.
Distance	Place	Intensity (MMI)
18 mi (29 km) N from epicenter	Oak Harbor Washington, The United States.	III Weak
19 mi (31 km) ESE from epicenter	Mukilteo Washington, The United States.	III Weak
22 mi (35 km) SE from epicenter	Edmonds Washington, The United States.	III Weak
22 mi (36 km) ESE from epicenter	Picnic Point-North Lynnwood Washington, The United States.	III Weak
23 mi (37 km) SE from epicenter	Lynnwood Washington, The United States.	III Weak
24 mi (38 km) E from epicenter	Everett Washington, The United States.	III Weak
24 mi (39 km) E from epicenter	Marysville Washington, The United States.	III Weak
25 mi (40 km) ESE from epicenter	Martha Lake Washington, The United States.	III Weak
25 mi (40 km) SE from epicenter	Mountlake Terrace Washington, The United States.	III Weak
25 mi (41 km) SE from epicenter	Shoreline Washington, The United States.	II Weak
26 mi (42 km) ESE from epicenter	Eastmont Washington, The United States.	III Weak
26 mi (42 km) ESE from epicenter	Mill Creek Washington, The United States.	III Weak
27 mi (43 km) SE from epicenter	Bothell West Washington, The United States.	III Weak
27 mi (43 km) S from epicenter	Silverdale Washington, The United States.	III Weak
27 mi (44 km) ESE from epicenter	Mill Creek East Washington, The United States.	III Weak
28 mi (45 km) E from epicenter	West Lake Stevens Washington, The United States.	III Weak
28 mi (45 km) ESE from epicenter	Silver Firs Washington, The United States.	III Weak
29 mi (46 km) ESE from epicenter	North Creek Washington, The United States.	III Weak
29 mi (46 km) SE from epicenter	Kenmore Washington, The United States.	III Weak
29 mi (47 km) SSE from epicenter	Bainbridge Island Washington, The United States.	III Weak
29 mi (47 km) ENE from epicenter	Arlington Washington, The United States.	III Weak
30 mi (48 km) E from epicenter	Lake Stevens Washington, The United States.	III Weak
30 mi (48 km) SE from epicenter	Bothell Washington, The United States.	II Weak
31 mi (50 km) SE from epicenter	Inglewood-Finn Hill Washington, The United States.	II Weak
32 mi (51 km) NNE from epicenter	Mount Vernon Washington, The United States.	III Weak
32 mi (52 km) S from epicenter	Bremerton Washington, The United States.	III Weak
34 mi (54 km) SE from epicenter	Kirkland Washington, The United States.	II Weak
34 mi (54 km) N from epicenter	Anacortes Washington, The United States.	III Weak
34 mi (55 km) W from epicenter	Port Angeles Washington, The United States.	II Weak
34 mi (55 km) SSE from epicenter	Seattle Washington, The United States.	III Weak
35 mi (57 km) SE from epicenter	Cottage Lake Washington, The United States.	II Weak
37 mi (59 km) SE from epicenter	Redmond Washington, The United States.	II Weak
37 mi (60 km) SE from epicenter	Bellevue Washington, The United States.	II Weak
39 mi (63 km) SE from epicenter	Mercer Island Washington, The United States.	II Weak
40 mi (64 km) SE from epicenter	Sammamish Washington, The United States.	II Weak
66 km (41 mi) NW from epicenter	Victoria British Columbia, Canada.	III Weak
42 mi (68 km) SSE from epicenter	Burien Washington, The United States.	II Weak
42 mi (68 km) SE from epicenter	West Lake Sammamish Washington, The United States.	II Weak
43 mi (69 km) SE from epicenter	City of Sammamish Washington, The United States.	II Weak
44 mi (71 km) SSE from epicenter	Renton Washington, The United States.	III Weak
45 mi (72 km) SSE from epicenter	SeaTac Washington, The United States.	II Weak
47 mi (75 km) SE from epicenter	Issaquah Washington, The United States.	II Weak
75 km (47 mi) NW from epicenter	Langford British Columbia, Canada.	III Weak
50 mi (81 km) SSE from epicenter	Kent Washington, The United States.	II Weak
51 mi (82 km) N from epicenter	Bellingham Washington, The United States.	II Weak
52 mi (84 km) SSE from epicenter	Federal Way Washington, The United States.	II Weak
55 mi (88 km) SSE from epicenter	Auburn Washington, The United States.	II Weak
55 mi (89 km) SSE from epicenter	Tacoma Washington, The United States.	II Weak
60 mi (97 km) S from epicenter	Lakewood Washington, The United States.	II Weak
120 km (75 mi) N from epicenter	Surrey British Columbia, Canada.
139 km (86 mi) NNW from epicenter	Vancouver British Columbia, Canada.
173 mi (279 km) S from epicenter	Portland Oregon, The United States.

Earthquake Intensity Map

The graph below overlays a map of the region around the epicenter with earthquake intensity data provided by the US Geographic Survey. The highest intensity level detected for this earthquake is IV.

I Not felt

II Weak

III Weak

IV Light

V Moderate

VI Strong

VII Very Strong

VIII Severe

IX Violent

X Extreme

Earthquake Intensity Map based on Shakemap Data provided by USGS.

Shaking reported by 49 people

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 49 people have reported shaking in 14 places, all within Canada.We keep updating this article as more ground reports become available. You may report that you felt this earthquake here.

Places with most reports:

Victoria, British Columbia, Canada: 23 people.
Vancouver, British Columbia, Canada: 7 people.
Abbotsford, British Columbia, Canada: 3 people.
Walnut Grove, British Columbia, Canada: 3 people.
White Rock, British Columbia, Canada: 3 people.
Sidney, British Columbia, Canada: 2 people.
Calgary, Alberta, Canada: 1 person.
Aldergrove, British Columbia, Canada: 1 person.
Chilliwack, British Columbia, Canada: 1 person.
Courtenay, British Columbia, Canada: 1 person.

Risk of aftershocks?

We have not yet detected any foreshocks or aftershocks (MAG-2.5 or higher) within 100km (62 mi) of this earthquake.

The risk of aftershocks decreases rapidly over time. Usually, aftershocks are at least one order of magnitude lower than a main shock.

In only six percent of cases, significant earthquakes are followed by a larger main shock, making the current earthquake a foreshock. While the chance of this happening is not so large, it is adviced to maintain cautiousness in the hours and days following a major earthquake.

Read: How to Stay Safe during an Earthquake (cdc.gov).

Earthquakes like this are common in the region

Earthquakes of this strength occur quite regularly in the region. This is the strongest earthquake to hit since November 26th, 2022, when a 4.9 magnitude earthquake hit 177 mi (284 km) further west-northwest. That was also the heaviest earthquake to hit the region in the past 10 years.

In total, 5 earthquakes with a magnitude of 4.3 or higher have been registered within 300km (186 mi) of this epicenter in the past 10 years. This comes down to an average of once every 2 years.

Sources

Last updated 07/12/23 06:28 (). This article contains currently available information about the earthquake and is automatically composed. We continue to update this article up to a few days after the earthquake occurred.