Significant earthquakes of 1983

November 30, 1983 Earthquake: Diego Garcia, Chagos Archipelago, Indian Ocean, UK Territories

November 30, 1983 · M7.6

A magnitude 7.6 earthquake struck Diego Garcia, Chagos Archipelago, Indian Ocean, UK Territories on November 30, 1983 at 17:46:00 UTC, 10 km below the surface. It caused a tsunami.

Map

Where it struck, with the other significant earthquakes within 200 km. Circles are sized and colored by magnitude; select one for its page.

The earthquake

Date
November 30, 1983
Time
17:46:00 UTC
Place
Diego Garcia, Chagos Archipelago, Indian Ocean, UK Territories
Magnitude
7.6 (Ms)
Focal depth
10 km (6 mi)
Intensity
6 on the Modified Mercalli scale
Epicenter
6.852° S, 72.110° E

The toll

Damage
Limited (under about $1 million)

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.

Some damage to buildings and piers on Diego Garcia. Five foot rise in wave height in the lagoon and significant wave damage near the southeastern tip of the island. 40 cm tsunami at Victoria, Seychelles. Large zone of discolored sea water observed 35 to 40 nautical miles north-northwest of Diego Garcia. (reference #1053)

More

Significant earthquakes of 1983The 1900sEvery quake the USGS located in 1983Recent earthquakes near hereThis day in weather history

Sources

Significant earthquakes 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 earthquake 5007.