The Honolulu Advertiser reports that there were 13,000 earthquakes were recorded in 2004 by the U.S. Geological Survey’s Hawaiian Volcano Observatory, only three were greater than magnitude 4. The average is 10,000 but Observatory seismologist Paul Okubo said there were fewer moderate to large quakes in the past year. There were 4,228 quakes were magnitude 1.5 or greater, and only 79 were big enough to have been felt by Big Island residents. The three largest quakes of 2004 Ã¢â‚¬â€ none greater than 4.5 Ã¢â‚¬â€ occurred beneath Kilauea on Feb. 5, Oct. 11 and Oct. 12. The principal source of earthquakes are Kilauea, Mauna Loa and Lo’ihi, all active volcanoes. Lo’ihi, about 6 miles south of the Big Island and 2,000 feet deep, is the youngest. It is expected to rise above sea level sometime in the next few thousand years. The most recent big earthquake in Hawai’i occurred in 1975 when a magnitude 7.2 temblor shook the Big Island, causing a tsunami that killed two campers in Halape, Puna.
The article was prompted by a 3.6 quake this week between Waiki’i and the Mauna Kea summit at a depth of 13 miles. Books on earthquakes.
Posted in Earthquakes, Hawaii, Phenomenon by roger with .