QQuakeFacts
USGS iscgem845214

4 Jul 1966, 19:33

246 km W of Adak, Alaska

A magnitude 6.8 mw earthquake at 17.6 km depth.

Depth17.6 kmPublished hypocentral depth
Tsunami flagNot flaggedUSGS catalog flag, not a current warning
Updated19 December 2025Latest timestamp stored in this record

Published location

Where is 246 km W 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.

51.789000, 179.798000

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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
iscgem845214
Coordinates
51.789, 179.798
Network
iscgem
Significance
711