QuakeFactsEvidence report · prepared 2 September 2026https://quakes99.com/entity/iscgem889477
USGS iscgem889477
28 Apr 1955, 20:05
122 km WSW of Adak, Alaska
A magnitude 6.4 mw earthquake at 35 km depth.
Published location
Where is 122 km WSW of Adak, Alaska?
This locator uses the coordinates in the approved source record. It shows geographic context, not a site boundary, safety zone or property-risk area.
51.410000, -178.236000
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What the numbers mean
Magnitude measures event size; depth locates the source below the surface. Neither value alone establishes local damage or personal risk.
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Use local emergency authorities and the live USGS event page. This historical evidence page is not an alert service.
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Catalog fields and provenance
Event ID
iscgem889477
Coordinates
51.41, -178.236
Network
iscgem
Significance
634