A magnitude 8.7 earthquake was detected off the coast of Russia’s Kamchatka Peninsula Tuesday afternoon. It is potentially one of the ten largest earthquakes ever recorded worldwide, and the largest in more than a decade according to the United States Geological Survey.
The quake triggered tsunami watches and warnings along the Aleutian Islands and a tsunami advisory as far south as Los Angeles. No such advisories have been issued for the Bering Strait region.
Tuesday evening, Nome's Emergency Services team stood up its Emergency Operations Center in response to the quake. Nome City Manager Lee Smith said he did not believe there was a threat, but that the team would continue monitoring the situation.
Of concern to emergency responders was a lack of buoys to monitor wave height between the Aleutians and Norton Sound region. The closest sea-based buoy to Nome is near St. Paul Island, just over 500 miles to the south.
Elena Suleimani is a tsunami modeler at University of Alaska Fairbanks' Alaska Earthquake Center. She said the buoys are strategically placed near areas with the highest seismic activity.
“If we had an unlimited amount of funds we would probably put those buoys in the Bering Sea, but at this point, they just place them where the hazard is most sure, which is in the Pacific,” Suleimani said.
She said subduction zones along the Aleutians and Kamchatka Peninsula commonly cause earthquakes, like the magnitude 7.3 observed near Sand Point on July 16. But she said areas like the Norton Sound have an advantage against earthquakes, thanks to the shallow waters north of the Bering Sea shelf.
“The energy can, of course, propagate into the Bering Sea, but then when it hits that shelf, waves slow down a lot, and communities on the west coast of Alaska, they have that advantage of having many hours before that wave arrives,” Suleimani explained.
She cited energy patterns from 1964’s fatal 9.2–9.3 megathrust earthquake as an example of the effect the shelf has. An animation Suleimani created showed waves heights rapidly slowing upon hitting the shelf. The 1964 earthquake was the second most powerful ever recorded in North America.
The Alaska Earthquake Center said it will continue to monitor local reports of wave heights and provide updates on its website.
