August 20, 1920 Earthquake: Off Coast Central, Chile
A magnitude 7 earthquake struck Off Coast Central, Chile on August 20, 1920 at 16:15:38 UTC, 15 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
- August 20, 1920
- Time
- 16:15:38 UTC
- Place
- Off Coast Central, Chile
- Magnitude
- 7 (Ms)
- Focal depth
- 15 km (9 mi)
- Tsunami
- Yes: the tsunami it caused
- Epicenter
- 38.000° S, 73.500° W
- Country
- Chile
The toll
- Damage
- Moderate (about $1 to $5 million)
- Houses destroyed
- Some (about 51 to 100)
- Houses damaged
- Some (about 51 to 100)
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.
August 20, 1920, 11:30 [local time], 38 S, 73.5 W, magnitude 7. There was an earthquake on the coast of Chile which was felt from the mouth of the Mataquito River to Reloncavi Fiord. At Angol, several public buildings, including the school, were seriously damaged, and a number of homes were virtually demolished. On Mocha Island, two lighthouses cracked to the foundation and became unserviceable and the tower of the eastern lighthouse was in danger of falling. All the structures damaged had been in an extremely dilapidated condition. The earthquake was not felt at Santiago. On Mocha Island, 21 aftershocks were noted on the same day, more than at any other point on the coast. In the harbor at Talcahuano, the movements of the water, which followed the earthquake, tossed about the vessels riding at anchor. (reference #415)
August 20, 1920, 16:15:28, 38 S, 73.5 W. (reference #1206)
August 20, 1920, 16:15:28, 38 S, 73.5 W, depth 15 km, magnitude 5.5. (reference #164)
Other significant earthquakes nearby
Within 200 km, the deadliest first.
- May 22, 1960, Puerto Montt, Valdivia, Chile
- February 8, 1570, Old Concepcion, Chile
- April 20, 1949, Angol, Traiguen, Chile
- February 20, 1835, Concepcion, Chile
- March 15, 1657, Concepcion, Chillan, Chile
- May 6, 1953, Chillan, Concepcion, Chile
- July 23, 1898, Concepcion, Chile
- May 21, 1960, Central, Chile
- May 10, 1975, Central, Chile
- May 3, 2004, Canete, Chile
- August 18, 1974, La Union, Valdivia, Chile
- October 28, 1562, Chile
- February 14, 1962, Central, Chile
- June 15, 2004, Carahue, Imperial, Temuco, Chile
- March 23, 1742, Concepcion, Chile
More
Significant earthquakes of 1920The 1900sEvery quake the USGS located in 1920Recent 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 6273.