No tsunami threat to Samoa
The Samoa Meteorology Service has advised that a 7.4 magnitude earthquake that struck the Alaska region Tuesday morning did not pose a tsunami threat.
The earthquake had a depth of 41km and was located 7,694.69 kilometres north of Apia.
In a post on its Facebook page on Tuesday 11.12am [Samoa Time], the S.M.S. stated: “There is no tsunami threat to Samoa!”
The U.S. Geological Survey [U.S.G.S.] in an advisory on its website stated that the October 19 earthquake south of the Alaska Peninsula was the result of strike-slip faulting close to the subduction zone interface between the Pacific and North America plates.
It further reiterated that the geological event is an aftershock of a 7.8 magnitude earthquake that occurred on 22 July 2020.
According to the U.S.G.S. since the 1900s eight other earthquakes with magnitudes of 7.0 or larger occurred within the 250km radius of the area that the Tuesday morning earthquake occurred. This includes the 22 July 2020 earthquake.
The largest of the eight earthquakes, measuring 8.6 on the Richter scale and striking on 1 April 1946, generated a large tsunami that brought destruction to the population on Unimak Island and Hilo in Hawaii.
“The Alaska-Aleutian Trench also hosted the second largest earthquake recorded by modern seismic instrumentation, the M9.2 March 27, 1964 earthquake, which ruptured to within about 350 km of this event,” the U.S.G.S. advisory further stated.
Unimak Island is the largest in the Aleutian chain of islands in the American state of Alaska.