Tsunamis in 1766

October 21, 1766 Tsunami: Cumana, Venezuela

October 21, 1766 · Very doubtful tsunami

A tsunami caused by a magnitude 7.5 earthquake began at Cumana, Venezuela on October 21, 1766 at 09:00 UTC. Its effects were recorded at 1 place.

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
October 21, 1766, 09:00 UTC
Source
Cumana, Venezuela
Cause
Earthquake
Earthquake
Magnitude 7.5
Runups recorded
1
Waters
Ocean
How certain
Very doubtful tsunami
Source location
10.470° N, 64.170° W

The toll

Damage
Moderate (about $1 to $5 million); Severe (about $5 to $25 million) with the earthquake or eruption that caused it

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.

Very violent shocks destroyed Cumana, Venezuela, and caused the island of Orinoco (Venezuela) to sink and disappear. In many places the water surface was disturbed. (reference #537)

Este terremoto conocido coloquialmente como el terremoto de Santa Ursula, por haber ocurrido en dia senalado por el santoral catolico, tuvo varios efectos geologicos co-sismicos en las costas orientales venezolanas, donde destacan terrenos elevados (p.e. Punta Delgada,Cumana), caída de bloques (Cerro Paruani, Península de Paria), y terrenos en subsidencia (sin especificar lugar de ocurrencia; O'Loughlin & Lander, 2003). Este ultimo efecto podria ser eventualmente interpretado como una inundacion por olas tsunamis, aunque podria tratarse de movimientos en masa con hundimiento del terreno.[This latter effect could eventually be interpreted as a tsunami flood, although it could due to mass movements with subsidence.] (reference #11659)

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
Isla OrinocoVenezuela322Eyewitness observation of water height

More

Every tsunami in 1766The 1700sTsunamis of VenezuelaThe 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 490.