M 4.5 earthquake: North Pacific Ocean (Japan) — April 20, 1983

M 4.5 earthquake: North Pacific Ocean (Japan) — April 20, 1983. Epicenter 600 km S of Hamamatsu, depth 461 km, 00:05 Local (1983-04-19 15:05 UTC). Readings from every reporting agency, affected towns, aftershock sequence.

North Pacific Ocean (600 km S, Japan) — 29.391, 138.717

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