QuakeFactsEvidence report · prepared 2 September 2026https://quakes99.com/entity/usp0000d42
USGS usp0000d42
11 Oct 1975, 15:35
south of Tonga
A magnitude 7.8 ms earthquake at 9 km depth.
Published location
Where is south of Tonga?
This locator uses the coordinates in the approved source record. It shows geographic context, not a site boundary, safety zone or property-risk area.
-24.894000, -175.119000
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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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Nearby events with a similar magnitude
Catalog fields and provenance
Event ID
usp0000d42
Coordinates
-24.894, -175.119
Network
us
Significance
936