August 7, 1915 Tsunami: Ionian Sea, Greece

Name: August 7, 1915 Tsunami: Ionian Sea, Greece
Start: 1915-08-07
Location: Ionian Sea, Greece

August 7, 1915 · 1.5 m · Questionable tsunami

A tsunami caused by a magnitude 6.7 earthquake began at Ionian Sea, Greece on August 7, 1915 at 15:04:03 UTC. The water rose as high as 1.5 meters. 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

Tsunami warnings in force

Travel times

How long the first wave took to reach each part of the ocean, one line for each hour up to 24, estimated from the source and the depth of the sea.

The travel times are computed in your browser, which needs JavaScript.

1 to 4 hours
5 to 6 hours
7 to 14 hours
15 hours and more

Computed in your browser the way NOAA’s own travel time maps are: the wave travels at the square root of gravity times the depth, over NOAA’s ETOPO1 depths averaged to a 10 arc-minute grid. Checked against NOAA NCEI’s maps for 21 tsunamis over the first 24 hours, these lines fall within 10 minutes of NCEI’s at half the points compared and within 52 minutes at 9 in 10. They give when the first wave could arrive, not how high it is; bays, harbors and island chains finer than the grid can see it later. Not for use in a warning: see tsunami.gov.

The tsunami

Date: August 7, 1915, 15:04:03 UTC
Source: Ionian Sea, Greece
Cause: Earthquake
Earthquake: Magnitude 6.7, 14 km deep
Maximum water height: 1.5 m (4.9 ft)
Runups recorded: 2
Tsunami intensity (Soloviev-Imamura): 3
Waters: Ocean
How certain: Questionable tsunami
Source location: 38.500° N, 20.700° E

The toll

Damage: Severe (about $5 to $25 million) with the earthquake or eruption that caused it
Houses destroyed: Many (101 to 1,000) with the earthquake or eruption that caused it
Houses damaged: Some (about 51 to 100) 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.

1915, August 7, 17h22m UTC. 39.1 N, 21.6 E, depth 14 km, magnitude 6-6.5, intensity VIII. Possible tsunami. In the Ionian Sea, Ionian Islands, a fairly strong earthquake caused great destruction on the northern slopes of the Islands of Kefallonia and Ithaca and in the southern part of the Island of Levkas. Two waves 1.5 m high (5 feet) were observed between the Islands of Kefallonia and Levkas. (reference #2130)

1915, August 7, 15:04:03 UTC. Earthquake 38o30'N, 20o42'E, magnitude 6.7, intensity IX, tsunami reliability 0 (very improbable). Violent shock at Ithaca, Ionian Islands. Fissures in the ground, slumps, changes in wells, rockslides. Mesoseismal area radius 220 km. Between Cephalonia and Leukada two tsunamis occurred, according to Galanopoulos (r 433). Tsunami intensity III at St. Maura (Leukada) according to Antonopoulos (r417). Further references: Soloviev (r414), Galanopoulos (r479), Papadopoulos (r80). (reference #4139)

1915 August 7, 15h04m UTC. 38.5 N, 20.7 E, improbable tsunami. (reference #11164, v2)

Just before the earthquake, the sea between Cephalonia and Leukada was upset and two opposite large waves were formed and were directed to the south. In Leukada, the earthquake was preceded by noise which carne from the sea (reference #4408)

possible tsunami (reference #416)

probable tsunami (reference #2591)

An earthquake of magnitude 6 - 6 1/4 was followed by two tsunamis between Cephalonia and Leukas (reference #109)

“Before the earthquake an oscillation of the sea was generated between the islands of Cephalonia and Lefkada. The result was that two waves were produced moving in opposite directions towards the two coasts”. This observation, however, does not explain how much time before the earthquake the sea oscillation occurred. The generation of two waves may indicate the reflection of an initial oscillation. However, the occurrence of the phenomenon before the earthquake is hardly explainable. We do not rule out that the sea oscillation occurred very soon after the earthquake, but the observer is confused about the exact time of this phenomenon. (reference #13999)

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
Kefallonia Island, Ionian Islands	Greece	11	1.5		Eyewitness observation of water height
Levkas Island, Ionian Islands	Greece	25	1.5		Eyewitness observation of water height

Every tsunami in 1915 The 1900s Tsunamis of Greece The earthquake This day in weather history Alerts 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 1427.