QQuakeFacts
USGS iscgem912384

8 Dec 1921, 12:31

6 km NNW of Narita, Japan

A magnitude 6.4 mw earthquake at 60 km depth.

Depth60 kmPublished hypocentral depth
Tsunami flagNot flaggedUSGS catalog flag, not a current warning
Updated25 April 2022Latest timestamp stored in this record

Published location

Where is 6 km NNW of Narita, Japan?

This locator uses the coordinates in the approved source record. It shows geographic context, not a site boundary, safety zone or property-risk area.

35.843000, 140.294000

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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
iscgem912384
Coordinates
35.843, 140.294
Network
iscgem
Significance
636