QuakeFactsEvidence report · prepared 2 September 2026https://quakes99.com/entity/iscgemsup786541
USGS iscgemsup786541
23 Mar 1971, 03:15
225 km SSW of ‘Ohonua, Tonga
A magnitude 6.3 mw earthquake at 73.1 km depth.
Published location
Where is 225 km SSW of ‘Ohonua, 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.
-23.067000, -176.112000
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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
iscgemsup786541
Coordinates
-23.067, -176.112
Network
iscgemsup
Significance
605