Data last collected:
QuakeFactsEvidence report · prepared 19 October 2026https://quakes99.com/entity/iscgem907412
USGS iscgem907412
20 May 1930, 12:15
280 km W of Adak, Alaska
A magnitude 6.5 mw earthquake at 25 km depth.
Published location
Where is 280 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.
51.510000, 179.345000
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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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Nearby events with a similar magnitude
Catalog fields and provenance
Event ID
iscgem907412
Coordinates
51.51, 179.345
Network
iscgem
Significance
644
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Questions this evidence can answer
01What exactly is this record?
Use the name, place, date and identifiers above to confirm that you have the right 280 km W of Adak, Alaska earthquake: magnitude 6.5 and depth | QuakeFacts record.
02What does the evidence establish?
Read the reported values with their units, coverage dates and source notes. Keep observed facts separate from estimates or interpretation.
03What should I verify next?
Follow the primary-source links and check the limitations before using this evidence for a decision, comparison or citation.
A closer look at 280 km W of Adak, Alaska
Depth in another unit
The recorded event depth of 25 km is approximately 15.53 miles below the source reference surface. Depth alone does not describe damage or local hazard.
Interpreting the recorded coordinates
The published position for 280 km W of Adak, Alaska is 51.51° north and 179.345° east. This expresses the source coordinates in hemispheres; it does not establish an entrance, public access or a safe route.