Tsunamis in 1921

November 11, 1921 Tsunami: Philippine Trench, Philippines

November 11, 1921 · Probable tsunami

A tsunami caused by a magnitude 7.5 earthquake began at Philippine Trench, Philippines on November 11, 1921 at 18:36:08 UTC. Its effects were recorded at 4 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

Tsunami warnings in force

The tsunami

Date
November 11, 1921, 18:36:08 UTC
Source
Philippine Trench, Philippines
Cause
Earthquake
Earthquake
Magnitude 7.5
Runups recorded
4
Tsunami intensity (Soloviev-Imamura)
1
Tsunami magnitude (Iida)
0.5
Waters
Ocean
How certain
Probable tsunami
Source location
8.000° N, 127.000° E

The toll

Damage
Limited (under about $1 million)
Houses destroyed
Few (about 1 to 50)

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.

Reference #414:

1921, November 7, 0:02 [local time]. There was an

earthquake with source off the southeastern coast of Mindanao Island in the form of sudden vertical shocks. Many recurrent shocks occurred; their frequency markedly decreased by the 10th but began to increase again on the 11th. The main earthquake struck at night on the 12th, and was accompanied by a large number of aftershocks.

After the main earthquake, a tsunami arose, which inundated the low-lying coasts of several bays, for example, at Manay, and did some damage to structures and plantations there. The tsunami was also observed at Manganitu on Sangihe Island.

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Every runup

Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.

WhereCountryKm from sourceWater height, mInland, mMeasured byFirst wave, UTCDeaths
Caraga Bay, Mindanao IslandPhilippines89Eyewitness observation of water height
Manay, Mindanao IslandPhilippines101Eyewitness observation of water height
Mati, Mindanao IslandPhilippines145Eyewitness observation of water height
Manganitu, Sangihe IslandPhilippines515Eyewitness observation of water height

More

Every tsunami in 1921The 1900sTsunamis of PhilippinesThe 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 1491.