QQuakeFacts
USGS iscgem911478

31 Jul 1923, 16:07

124 km SSW of Attu Station, Alaska

A magnitude 6.4 mw earthquake at 15 km depth.

Depth15 kmPublished hypocentral depth
Tsunami flagNot flaggedUSGS catalog flag, not a current warning
Updated25 April 2022Latest timestamp stored in this record

Published location

Where is 124 km SSW of Attu Station, 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.

51.823000, 172.458000

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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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Catalog fields and provenance
Event ID
iscgem911478
Coordinates
51.823, 172.458
Network
iscgem
Significance
630