QuakeFactsEvidence report · prepared 2 September 2026https://quakes99.com/entity/iscgem886577
USGS iscgem886577
21 May 1957, 02:12
Mariana Islands region
A magnitude 6.3 mw earthquake at 101.7 km depth.
Published location
Where is Mariana Islands region?
This locator uses the coordinates in the approved source record. It shows geographic context, not a site boundary, safety zone or property-risk area.
21.827000, 144.215000
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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
iscgem886577
Coordinates
21.827, 144.215
Network
iscgem
Significance
616