How strong was the 78 km NNW of Adak, Alaska earthquake?
The 78 km NNW of Adak, Alaska earthquake had a magnitude of 6.4 mww, classified as a "Strong" earthquake on the magnitude scale. Earthquakes of this size can cause serious damage to buildings and infrastructure over a wide area.
Where exactly did this earthquake occur and how deep was it?
This earthquake struck at coordinates 52.5592N, 176.9240W, at a depth of 174.0 km. Deep earthquakes are generally felt over a wider area but cause less intense shaking at the surface.
Did this earthquake trigger a tsunami warning?
Yes, a tsunami advisory or warning was associated with this earthquake. Coastal residents in affected areas should always follow local emergency management guidance during tsunami events. Even small tsunamis can produce dangerous currents.
How many people felt this earthquake?
12 people submitted felt reports to the USGS for this earthquake. The Community Decimal Intensity (CDI) reached 4.9, indicating moderate shaking felt by most people indoors. The Modified Mercalli Intensity (MMI) was estimated at 5.1.
When did this earthquake happen and how significant was it?
This earthquake occurred on October 16, 2023 at 20:35:30. The USGS assigned it a significance score of 636 out of a possible 3,000, which factors in magnitude, felt reports, and potential impact. This is a moderately significant seismic event. The PAGER alert level was "green", indicating the estimated level of response needed.