Data last collected:
QuakeFactsEvidence report · prepared 25 October 2026https://quakes99.com/entity/iscgem775639
USGS iscgem775639
24 Mar 1972, 04:38
77 km ESE of Chignik, Alaska
A magnitude 6.4 mw earthquake at 69.6 km depth.
Published location
Where is 77 km ESE of Chignik, 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.
56.132000, -157.190000
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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
iscgem775639
Coordinates
56.132, -157.19
Network
iscgem
Significance
622
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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 77 km ESE of Chignik, Alaska earthquake: magnitude 6.4 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 77 km ESE of Chignik, Alaska
Depth in another unit
The recorded event depth of 69.6 km is approximately 43.25 miles below the source reference surface. Depth alone does not describe damage or local hazard.
Interpreting the recorded coordinates
The published position for 77 km ESE of Chignik, Alaska is 56.132° north and 157.19° west. This expresses the source coordinates in hemispheres; it does not establish an entrance, public access or a safe route.