Historical tsunamis · Mar 9, 1931, 3:49 AM UTC

1931 Sanriku tsunami

Japan

The tsunami of Mar 9, 1931, 3:49 AM UTC originated near Sanriku (Japan).

Key facts

Date: Mar 9, 1931, 3:49 AM UTC
Cause: Earthquake
Magnitude: M7.6
Depth: 60 km
Maximum documented water height: 0.40 m
Observation records: 7
Countries affected: 1

It was triggered by a magnitude 7.6 earthquake at a depth of 60 km.

The highest documented water height was 0.40 m.

7 observation sites in 1 countries are recorded.

All tsunamis in Japan Record at NOAA/NCEI ↗

Map of observation sites

Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.

Tsunami arrival times

Documented arrival times from the NOAA/NCEI database, showing the earliest recorded location per country. Coverage is incomplete: a country without an entry was not necessarily spared.

0:00 hEarthquake (origin) · Mar 9, 1931, 3:49 AM UTC
0:36 hJapan · Miyako

7 places with a documented arrival time

Observations by country

Country	Observation records	Maximum documented water height	Deaths	Earliest arrival
Japan	7	0.20 m Hachinohe	—	0:36 h

Highest documented water heights

7 / 7

Individual documented observations for this event. Heights come from different measurement types and sources; not every location has a measured height.

Location / station	Observed height	Distance from source	Country
Hachinohe · Aomori	0.20 m	110 km	Japan
Tsukihama · Miyagi	0.09 m	306 km	Japan
Ishinomaki · Miyagi	0.07 m	326 km	Japan
Onahama · Fukushima	0.04 m	494 km	Japan
Oshima (Shiogamako) · Miyagi	0.03 m	347 km	Japan
Ayukawa · Miyagi	—	333 km	Japan
Miyako · Iwate	—	178 km	Japan

Source: NOAA National Centers for Environmental Information (NCEI), Global Historical Tsunami Database. Confirmed events only. Deaths and damage are database estimates; older records are incomplete. Water heights come from different types of observation.