QuakeFactsEvidence report · prepared 2 September 2026https://quakes99.com/entity/iscgem901677
USGS iscgem901677
30 Oct 1940, 04:10
central Mid-Atlantic Ridge
A magnitude 6.3 mw earthquake at 15 km depth.
Published location
Where is central Mid-Atlantic Ridge?
This locator uses the coordinates in the approved source record. It shows geographic context, not a site boundary, safety zone or property-risk area.
-1.644000, -20.938000
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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
iscgem901677
Coordinates
-1.644, -20.938
Network
iscgem
Significance
614