October 28, 2012
Tsunami Hits Hawaii Following Earthquake In British Columbia
redOrbit Staff & Wire Reports - Your Universe Online
A magnitude 7.7 earthquake struck the Canadian province of British Columbia late Saturday night, leading to short-lived tsunami warnings and mass evacuations as far away as Hawaii, according to various media reports.
The earthquake was centered in the Queen Charlotte Islands area (also known as Haida Gwaii) of British Columbia, US Geological Survey (USGS) officials told Mark Thiessen and Oskar Garcia of the Associated Press (AP), and was followed by a 5.8-magnitiude aftershock shortly thereafter. There were no immediate reports of damage, although the seismic event was felt as far away as southeastern Alaska.
"Residents near the center of the quake said the violent jolting lasted for up to a minute, but no injuries or major damage had been reported," the Canadian Press confirmed early Sunday morning. One resident in the vicinity told the news agency that the quake lasted approximately 40 seconds, and Simon Fraser University earth scientists Brent Ward called it the second largest to hit Canada since 1949.
The earthquake, which CBC News reported hit at approximately 8pm PT, caused at least three tsunami waves spotted off the coast of the province, and led to evacuations and tsunami warnings in Haida Gwaii and Port Edward, near Prince Rupert. The Canadian Press also reports that similar warnings had been issued in Alaska and Hawaii.
Shortly before 6am ET Sunday morning, NBC News confirmed that Hawaii had been hit by a tsunami, and that at least 100,000 people had been evacuated and directed to higher elevations. According to their reports, the Pacific Tsunami Warning Center said that the first wave was "three feet high and less forceful than expected. Some forecasts had predicted a wave of up to six feet high."
"The tsunami hit with little warning and an alert, issued at short notice due to initial confusion among scientists about the quake's undersea epicenter, caused massive traffic congestion as motorists made a mass exodus from low-lying areas," NBC News reported.
Tsunami waves were spotted in other areas as well, according to the CBC.
"Dennis Sinnott of the Canadian Institute of Ocean Science said a 69-centimeterre wave was recorded off Langara Island on the northeast tip of Haida Gwaii, formerly called the Queen Charlotte Islands," they said. "Another 55-centimeter wave hit Winter Harbour on the northeast coast of Vancouver Island, while a 12-centimeter wave was recorded in Tofino, on Vancouver Island's west coast."
Additional tsunami waves were believed possible in Hawaii. However, in southern Alaska and British Columbia, the warning was downgraded to an advisory shortly after 5am ET Sunday morning, Thiessen and Garcia said. They also noted that new advisories had been issued for parts of northern California and southern Oregon.
Ward told the Canadian Press that he was not surprised that the tsunami warning was shortlived in most areas, adding that tsunamis are not typically triggered by strike-slip movements along faults. He said that "a vertical movement of the sea floor" is required to displace water and create the massive waves. "Because it's sliding across each other" in a strike-slip movement, "you're not generally moving the water," he added.