Historic Earthquakes

Off the Coast of Ecuador
1906 January 31 15:35 UTC

Off the Coast of Ecuador

N.B: The magnitude for this earthquake has been recalculated since the following articles were written. Magnitude 8.8 is a better determination of the size of this earthquake.

A catastrophic magnitude 8.2 earthquake off the coast of Ecuador and Colombia generated a strong tsunami that killed 500 to 1500 there. It was observed all along the coast of Central America and as far north as San Francisco and west to Japan.....The wave arrived in Hilo at about 12.5 hours after the earthquake. It covered the floor of the old wharf at the end of Waianuenue Street and the railroad tracks between there and Waiakea. The range of oscillations in water level was 3.6 m and the period 30 minutes. The channels of the Wailuku and Wailoa Rivers alternately dried up, then disappeared under the tidal wave.

Kahului: Three waves arrived at 20-minute intervals. The second wave was larger than the first, and the third was larger than the second. The water rose about 0.30 m above the mean sea level mark. According to other sources, the water surface rose to the level of the old steamship pier and the road running along the coast.

The tide gauge at Honolulu began to register oscillations about 12 hours after the earthquake. The tsunami apparently began with a flood; then the oscillations intensified, and the fourth wave, which was the highest, had a height of 0.25 m. The period of oscillations was 20-30 minutes. Three separate trains of oscillations were registered.

According to the accounts of witnesses, disturbances in water level on Honolulu Bay began to be observed at 3:30 UTC February 1. At 4:15 UTC there as an extremely great ebb. All the steam and sailboats in the bay were turned around. Then a sudden flood tide reached a considerable height."

From Lander and Lockridge, 1989, Tsunami in Hawaii

A magnitude 8.2 earthquake off the coast of Ecuador produced a 5-m local tsunami that destroyed 49 houses and killed 500 people in Colombia. It was recorded at San Diego and San Francisco."

From Lander and Lockridge, 1989, Tsunami on west coast of United States