Significant earthquakes of 869

July 13, 869 Earthquake: Sanriku, Japan

July 13, 869 · M8.6 · Deaths: very many

A magnitude 8.6 earthquake struck Sanriku, Japan on July 13, 869. It caused a tsunami.

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
July 13, 869
Place
Sanriku, Japan
Magnitude
8.6 (Ms)
Epicenter
38.500° N, 143.800° E
Country
Japan

The toll

Deaths
Many (about 101 to 1,000); Very many (over 1,000) with its tsunami and other effects
Damage
Extreme (about $25 million or more)
Houses destroyed
Many (101 to 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.

A strong earthquake causing great destruction and with many victims occurred on the territory of Aomori, Iwate and Miyagi prefectures. Gleaming bands of light flared up several times, illuminating all objects as if in daylight. People could not stand could do nothing but shout for help. Some were crushed by fragments of collapsing homes and some were swallowed up by enormous cracks in the earth. Cows and horses milled about in terror, bumping into each other. An extraordinary number of temples, warehouses, gates and walls were thrown to the ground. Prolonged rumbling sounds, like thunder, were heard. The earthquake also generated a tsunami. [38.5 N, 143.8 E; M=8.6, m=4]. (reference #414)

Other significant earthquakes nearby

Within 200 km, the deadliest first.

More

Significant earthquakes of 869The 800sRecent 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 247.