Historic Earthquakes

Samana, Dominican Republic
1946 August 04 17:51 UTC
Magnitude 8.0

Aftershock
1946 August 08 13:28 UTC
Magnitude 7.6

100 deaths.
About 20,000 people left homeless and severe damage in northern Dominican Republic from Samana to Santiago and Puerto Plata. Some damage occurred at Santo Domingo (Ciudad Trujillo) and slumping and sand blows were observed in the Yaque del Norte and Yuna River Valleys. The death toll was light because the quake struck in early afternoon on a holiday, when most people were outdoors. It was felt strongly (V-VI) in parts of Haiti and Puerto Rico, including San Juan; and (III) in the Virgin Islands and eastern Cuba. Almost all the people killed were drowned by a tsunami at Matanzas, near Nagua (Julia Molina). Although the waves were only about 2.5 m (8 ft) high at this location, they moved inland several km, causing such severe damage that the town was abandoned. Maximum wave heights were estimated at 4-5 m (13-16 ft) at Nagua. A small tsunami was recorded by tide gauges at San Juan, Puerto Rico; Bermuda; Daytona Beach, Florida and Atlantic City, New Jersey.

A major aftershock (M 7.6) occurred on August 08, causing additional damage and also generating a slight tsunami that was recorded at the same tide stations.


This earthquake occurred about 65 km off the northeast coast of the Dominican Republic. The tsunami caused by this earthquake was recorded on the tide gage at San Juan, Puerto Rico. Reports from the north and west coast of Puerto Rico do not show evidence of a tsunami. (Berninghausen, 1968) The waves were recorded on tide gages at Daytona Beach, Florida, at Atlantic City, New Jersey, and at Bermuda. (Bodle and Murphy, 1948)

Abridged from United States Tsunamis, (including United States possessions) 1690-1988: Publication 41-2, Lander, James F., and Lockridge, Patricia A., August 1989, U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, 265 p.