Significant earthquakes of 1978

June 12, 1978 Earthquake: Sanriku, Japan

June 12, 1978 · M7.7 · 28 deaths · $865 million

A magnitude 7.7 earthquake struck Sanriku, Japan on June 12, 1978 at 08:14:26 UTC, 44 km below the surface. It killed 28 people.

Map

Where it struck, with the other significant earthquakes within 200 km. Circles are sized and colored by magnitude; select one for its page.

The earthquake

Date
June 12, 1978
Time
08:14:26 UTC
Place
Sanriku, Japan
Magnitude
7.7 (Ms)
Focal depth
44 km (27 mi)
Intensity
8 on the Modified Mercalli scale
Epicenter
38.190° N, 142.028° E
Country
Japan

The toll

Deaths
28
Injuries
10,000
Damage
$865 million
Houses destroyed
Very many (over 1,000)

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

What the record says

NCEI’s account, from the sources it cites.

On June 12, 1978, at 17:14 [local time] a strong earthquake of 7.4 magnitude caused extensive destruction in the northeastern part of Honshu. Its epicenter was located in Miyagi Prefecture. Particularly severe destruction was observed in Sendai. As a result of the earthquake 28 people died and nearly 10,000 were injured. Moreover, a tsunami generated by the earthquake caused panic among the people for some time. Damage caused by the tsunami was not observed. (reference #417)

22 killed, 421 injured and extensive damage in the Sendai area. (reference #1053)

27 deaths, $800 million damage. (reference #1231)

28 deaths, 2500 affected, $865 million damage. (reference #1250)

Other significant earthquakes nearby

Within 200 km, the deadliest first.

More

Significant earthquakes of 1978The 1900sEvery quake the USGS located in 1978Recent earthquakes near hereThis day in weather history

Sources

Significant earthquakes from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI earthquake 4806.