Tsunami Warnings Canceled Following Massive 7.9 Magnitude Earthquake in the Gulf of Alaska
January 23, 2018
The U.S. Tsunami Warning System has rescinded all threat warnings surrounding the Kodiak-area quake that occurred overnight Tuesday.
Via ktuu.com:
Tue Jan 23 12:42:38 UTC 2018 event picture pic.twitter.com/yRyGikpdVj
— NWS Tsunami Alerts (@NWS_NTWC) January 23, 2018
UPDATE, 7:30 a.m. - Even after the early morning earthquake in the Gulf of Alaska, the surrounding area felt a series of aftershocks.
John Bellini, a geophysicist with the U.S. Geological Survey's National Earthquake Information Center, told the Associated Press that there have been more than two dozen aftershocks as of about 6:30 a.m. The biggest aftershock reportedlyhad a magnitude of 5.3.
UPDATE, 4:25 a.m. - The U.S. Tsunami Warning System has rescinded all threat warnings surrounding the Kodiak-area quake that occurred overnight Tuesday.
Following the all clear, Kodiak's mayor and city manager took to Facebook Live, providing a rundown of what happened in the city during the tsunami warning.
"At 1 a.m. we activated the tsunami warning sirens, told people to evacuate from low lying areas, orderly, which they did. We appreciate that," said Mike Tvenge, city manager of Kodiak.
Tvenge continued to say that a harbor officer and harbor master were monitoring the water levels as they rose and fell Tuesday morning, up until the Tsunami Warning Center announcing the cancellation of the warning.
"We just want to thank everyone in Kodiak, especially the command center here," said Mayor Pat Branson. "We're very grateful that there wasn't a tsunami of any kind of magnitude."
School in Kodiak has been cancelled for Jan. 23 following the early morning disturbance.
"We live in a very prone earthquake and tsunami area," said Branson. "It's a beautiful place, but that's what you have when you live in paradise."
UPDATE, 3:20 a.m. - The National Oceanic and Atmospheric Admin. has dropped its tsunami warning down to 'Advisory' status.
The advisory stands for the coastline areas from Chignik Bay, Alaska, to the Hinchinbrook Entrance, about 90 miles east of Seward.
All other warnings, watches and advisories stemming from the Kodiak quake that took place on the morning of Jan. 23 have been cancelled.
UPDATE, 2:35 a.m. - Jeremy Zidek, of the Alaska Div. of Homeland Security and Emergency Management, said Tuesday morning that shake damage from the Tuesday morning earthquake is unlikely, but that the group does have concerns about tsunami waves.
"In Kodiak, they've activated their sirens," Zidek said. "The harbor master reported a wave did come in, but not a significant wave."
At least nine communities have evacuation orders in place. Zidek said that while the initial reports don't show shake damage just yet in Alaska, he implores people to follow community-issued evacuation warnings.
"Please get to high ground 300 feet above sea level or one mile inland, until [you] get report notifications from local authorities that everything is clear."
In Old Harbor, waves of about six inches have been reported. Keep in mind that second, third, and even subsequent waves beyond that can be more powerful.
The initial quake was initially estimated to be somewhere in the range of magnitude 8.0 and to have taken place about 12 miles below sea level in the Gulf of Alaska. The severity has dropped to M7.9 following U.S. Geological Survey review.
According to USGS, this is the twelfth earthquake in the last century, and within 600 kilometers of the source, to hit a magnitude of 7.0 or higher. The Kodiak quake reportedly occurred as a result of strike slip faulting where the Pacific tectonic plate converges with the North American plate.
A tsunami warning, including for communities in Alaska, is in effect for various areas.
Estimated possible tsunami start times are as follows:
Kodiak, Alaska - 145 AM
Seward, Alaska - 155 AM
Elfin Cove, Alaska - 155 AM
Sitka, Alaska - 200 AM
Yakutat, Alaska - 205 AM
Langara, British Columbia - 210 AM
Valdez, Alaska - 215 AM
Sand Point, Alaska - 220 AM
Cordova, Alaska - 225 AM
Unalaska, Alaska - 240 AM
Homer, Alaska - 255 AM
Craig, Alaska - 300 AM
Cold Bay, Alaska - 300 AM
Adak, Alaska - 305 AM
Tofino, British Columbia - 340 AM
Shemya, Alaska - 350 AM
Saint Paul, Alaska - 400 AM
If you are located in these coastal areas, move inland to higher ground. Especially if you are located in a low-lying area that is affected, you should evacuate immediately. Tsunami warnings mean that a tsunami - which can include a whole series of waves dangerous many hours after initial arrival time - with significant inundation is possible or is already occurring.
Please note that Anchorage is outside of the danger zone thus far. Much of the rest of the West Coast of the United States, as well as Hawaii, are under a Tsunami Watch at the time of publication.
- Blue Monster Prep
