Kenai Peninsula residents got a rude awakening early Sunday morning when a 7.1 magnitude earthquake hit the Lower Cook Inlet.
No injuries have been reported since the tremor clocked in at 1:30 a.m. It originated 17 miles north of Augustine Volcano and about 60 miles west of Homer, according to the Alaska Earthquake Information Center. Sarah Meyer, a research technician with the center, said it is not uncommon for a few different magnitude estimates to appear in the hours following a quake.
“We a lot of times underestimate the magnitude just because it takes more data to estimate the magnitude of an earthquake that size,” she said.
The earthquake was caused by a tectonic plate being pulled down into the mantel, Meyer said.
“It looks consistent with an earthquake resulting from the Pacific Plate subducting under the North American Plate,” she said.
The rupture happened inside the Pacific Plate as it subducted — or got pulled under — the North American Plate, not at the place where the two plates met, according to the center’s website.
Aftershocks can be expected for up to a few weeks, Meyer said, though it is unlikely anything will be close to the magnitude of Sunday’s quake.
“We’ve already seen hundreds of aftershocks,” Meyer said.
Meyer said this kind of earthquake is not uncommon. However, it is the largest “intermediate-depth earthquake” — its depth was 76 miles — to happen in the Cook Inlet since the regional seismic network was established in the 1960s, according to the center.
“It means that earthquakes of this size are infrequent but seem to, so far, happen once in a while in this location,” Meyer said. “We just haven’t been recording in the area long enough to establish a pattern.”
The earthquake left some severe damage in its wake. Two homes on Lilac Lane in Kenai were destroyed by gas explosions shortly after the quake, and two more caught fire and burned down as a result. All four houses were declared total losses by the Kenai Fire Department, said Fire Chief Jeff Tucker.
Lilac Lane, Cook Inlet View Drive and Wells Way were all evacuated and more than 20 residents were sent to the Kenai National Guard Armory where the Kenai Peninsula Borough Office of Emergency Management set up a temporary shelter.
“The first house they went out to was an explosion that caught a house on fire,” Tucker said. “A second house exploded and caught on fire, blew up basically… which then in turn caught the original house on fire.”
From there, fire spread to the second two houses, he said.
It is not clear exactly how the quake led to the explosions, but Enstar Natural Gas Co. Communications Manager Lindsay Hobson said employees spent Sunday shutting off gas to the area, digging up lines and checking to make sure there are no additional gas leaks. The first goal is to ensure safety, she said, and the second is to get heat back into the houses on the three streets as soon as possible through a temporary fix.
“We’re not going to do that until we’re sure it’s safe to do so,” Hobson said.
Homer Electric Association spent the day tackling power outages. By just before 8 a.m. on Sunday, the company had power restored to most areas, according to an HEA press release.
There are 44 meters in the Lilac Lane area still without power according to the release. HEA expected to restore power by Sunday night, according to a press release.
“We did during the day have some single outages,” said Director of Member Relations Joe Gallagher. “We did respond to a few of those throughout the day today.”
Meanwhile, the earthquake wreaked havoc on about 150 feet of highway on Kalifornsky Beach Road in Kasilof, putting a long crack into the pavement.
The Alaska Department of Transportation will begin preliminary repairs to the section of K-Beach Road on Monday. Shannon McCarthy, public information officer for the department’s central region, said the section of road in the northbound lane “dropped” down by about a foot. The department closed down that lane of the highway, she said.
The Alaska Department of Transportation will grind up and fill in that section of highway, and will make a permanent repair to the road this summer when weather is better, McCarthy said.
“Typically, the federal government will cooperate with emergency repairs,” McCarthy said of the cost to fix the road.
Angela Mann made the slog from Soldotna to assess the damage with son Treyden, 7, and daughter Ella, 4, Sunday afternoon. Standing beside the fissure she recalled she and her husband trying to get into their children’s room the night before, but a dresser had fallen over knocking a TV against the bedroom door.
“I was screaming ‘make it stop!’” Mann said, holding her hands over her ears and laughing in the sunshine, now that everyone was fine.
The family’s kitchen floor was the only casualty, she said. Most of the cupboards were cleaned out from the shaking. Afterward, her husband was called out to work, and she and her kids spent the night at Mann’s parents home, just up the hill from the large crack in the road.
“It’s pretty nuts,” Mann said. “I have never seen anything like this.”
Stephanie Boyd and her family also made the trip out to Kasilof to see the damages. She peered down into a slim section of the crack, which still went nearly five-feet down into the earth.
Boyd’s son Joshua, 13, used a seflie stick to slink inside the small cavern. Her husband, James Boyd, walked back and forth between his family and along the slanted roadway.
“We grew up in California, and have experienced a lot of earthquakes, but nothing had the throw and the jolt of that second 7.1-maginitude,” James Boyd said.
Several area businesses felt the effects of the tremor as well. Dressing, water bottles and other goods tumbled off the shelves at Safeway in Kenai. Kenai’s Walmart store also had a mess to clean up following the quake, said Store Manager Jennifer Gordon.
“We were doing our overnight shift when it happened and we closed the store immediately,” she said.
Walmart reopened around 9 a.m. after employees cleaned up, Gordon said. It was then that an associate called her from the temporary shelter after being evacuated, at which point Gordon said Walmart employees began gathering items to donate. The store gave food, clothing, sleeping bags, pillows, a television, movies, games and diapers to the shelter and evacuated families, Gordon said.
Kaladi Brothers Coffee in Soldotna donated three gallons of coffee, said Shift Captain Jacynne Colover. The store had a ceiling tile come loose during the quake, but suffered no other damage, she said.
Businesses in Homer got a good shake during the tremor as well. Alice’s Champagne Palace on Pioneer Avenue lost about two kegs of beer when several taps opened during the earthquake, said manager Josh Tobin.
“I guess the vibration shook the tap handle enough they opened,” he said.
The Homer Bookstore had some book displays knocked over, but did not have any visible damage.
The East End Grog Shop was not as lucky. Several liquor and wine bottles and cases of beer broke, leaving the air thick with the aroma of alcohol. The walk-in sustained the most damage, with all the beer on the bottom of the stacks crushed, and several broken bottles on the floor, coating the space with a layer of beer and glass.
Grog Shop owner Mel Strydom said he had about $1,000 in damages at his stores, the Grog Shop, the Grop Shop East on East End Road, and the Rum Locker on Ohlson Lane. A $300 bottle of Cristal champagne survived a fall, but a lot of lesser brands crashed and shattered.
“They didn’t tumble over. They danced over,” he said.
There was no damage to his buildings, Strydom said.
State Seismologist Mike West said that while more intense earthquakes have happened around Alaska, most of them do not occur near populations, so it can be easy for people to slip into a false sense of security.
“On the one hand, you can interpret that as, well, these things are rare, they don’t happen a lot,” West said. “On the other hand, just because we don’t see them often they still happen.”
West said, given that most large earthquakes in the state happen in remote areas, it would not be good for people to get the idea that high magnitude quakes in Alaska aren’t a big deal.
“This would have been a fundamentally different earthquake if it happened shallow under the Kenai Peninsula,” he said. “The same earthquake could be exponentially worse if it simply occurred in a different place.”
Kelly Sullivan, Michael Armstrong and Anna Frost contributed to this article.
Reach Megan Pacer at megan.pacer@peninsulaclarion.com. Reach Kelly Sullivan at kelly.sullivan@peninsulaclarion.com. Reach Michael Armstrong at michael.armstrong@homernews.com. Reach Anna Frost at anna.frost@homernews.com.