Tsunamis in 1757

July 9, 1757 Tsunami: Azores, Portugal

July 9, 1757 · 1,053 deaths · Probable tsunami

A tsunami caused by an earthquake began at Azores, Portugal on July 9, 1757 at 23:45 UTC. Its effects were recorded at 5 places. It killed 1,053 people, counting the earthquake or eruption that caused it.

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
July 9, 1757, 23:45 UTC
Source
Azores, Portugal
Cause
Earthquake
Earthquake
The earthquake
Runups recorded
5
Waters
Ocean
How certain
Probable tsunami
Source location
38.650° N, 28.080° W

The toll

Deaths
1,053 with the earthquake or eruption that caused it
Damage
Severe (about $5 to $25 million) with the earthquake or eruption that caused it
Houses destroyed
Very many (over 1,000) 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.

July 9, 1757, Azores. Sea was violently agigated and came in at St George Island [Sao Jorge], the Pic, and Graciosa. (reference #132)

July 9, 1757. Azores. The earthquake was felt throughout the Azores. Waves came in violently from west to east on Ilha de Sao Jorge, east to west on Ilha de Pico and the southwest on Ilha Graciosa (39 deg 04 min N., 28 deg 00 min W.). Waves were noted on Ilha Terceira. (reference #41)

July 9, 1757, 11:45 p.m., throughout the Azores. A terrible shock lasting about 2 minutes was at first vertical, but soon changed to horizontal, in the direction W. to E. The sea was in a state of great agitation, and came in violently on the land, in the direction W. to E. on the island of St. George, E. to W. on that of the Pic, and S.to W. on Graciosa. (reference #496)

July 9, 1757, throughout the Azores, Angra (Terceira), Island of St George; sea waves. (reference #1055)

On 9 July 1757, an earthquake with an epicentre in Faja dos Vimes (southern S. Jorge coast) raised a "sea flood in this island of Terceira which flowed from west to east: at Graciosa [the flood approached] from SW; in the island of Faial the earth trembled with less intense flooding" (Macedo, 1871). The impact of this flooding in Terceira is confirmed by Drummond (1850-64) and reported as not having produced damage. Despite the lack of explicit accounts of tsunami in S. Jorge, the description in Archivo do Acores (1882) implies that extensive landslides affected its coastline, creating significant expansions of new land, locally named "Fajas". (reference #5046)

event reliability 3 (probable tsunami). (reference #11164)

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
Sao JorgeAzores0Eyewitness observation of water height
Pico (Island)Azores28Eyewitness observation of water height
GraciosaAzores44Eyewitness observation of water height
Azores: Faial (Island)Azores55Eyewitness observation of water height
Ilha Terceira, AzoresAzores75Eyewitness observation of water height

More

Every tsunami in 1757The 1700sTsunamis of PortugalThe 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 462.