February 8, 1602 Tsunami: Boso, Japan
A tsunami caused by a magnitude 7.2 earthquake and a landslide began at Boso, Japan on February 8, 1602. Its effects were recorded at 2 places.
Where the waves reached
The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
The tsunami
- Date
- February 8, 1602
- Source
- Boso, Japan
- Cause
- Earthquake and landslide
- Earthquake
- Magnitude 7.2
- Runups recorded
- 2
- Tsunami intensity (Soloviev-Imamura)
- 1
- Tsunami magnitude (Iida)
- 1
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 35.100° N, 140.500° E
The toll
- Deaths
- Many (about 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.
February 8, 1602 [Kecho 6 12 16], 35.1 N, 140.5 E, magnitude 7.2. Big shock in Kazusa, Awa Provinces and flood tide, many persons and beasts killed. (reference #150)
February 7, 1602. A landslide came down into the sea from the Boso Peninsula, in Chiba Prefecture. The water retreated 300 m and returned on the following day (?). Many people and animals drowned. (reference #414)
January 1602 [Kecho 6 12 16]. Japan, Boso Peninsula. Landslide into sea. Tide retreated 300 m. Returned next day (?). Many men and beasts drowned. (reference #79)
Every runup
Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Kazusa, Awa | Japan | 9 | Eyewitness observation of water height | ||||
| Boso Peninsula | Japan | 63 | Eyewitness observation of water height |
More
Every tsunami in 1602The 1600sTsunamis of JapanThe earthquakeThis day in weather historyAlerts in force
Sources
Tsunami events and runups 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 tsunami event 207.