The U.S. Geological Survey (USGS) said that a strong 7.5-magnitude earthquake struck off the southeastern coast of Alaska just before midnight local time last night (January 4-5, 2013). A local tsunami warning was issued for parts of southern Alaska and coastal Canada, and it has now been withdrawn. The warning area extened for about 475 miles and included coastal areas from about 75 miles southeast of Cordova, Alaska, to the north tip of Vancouver Island, Canada, the Alaska Tsunami Warning Center said. There were no initial reports of damage from the earthquake.
Here are the details of the quake from USGS:
Date-Time Saturday, January 05, 2013 at Read more…
The lava dome covering Mt. Cleveland volcano in Alaska has grown by 25 percent since last week. The dome was reported to be 40 meters across on Monday Feb. 6., and has now increased to 50 meters in size, according to the Alaska Volcano Observatory (AVO).
“We got indications from satellite data that the dome had grown slightly,” Alaska Volcano Observatory Research Geologist Matt Haney said. “The recent expansion shows that growth has not ceased.”
The current lava dome is much smaller than the dome was before the last eruption of Mt. Cleveland.
“The previous lava dome that was removed by explosive activity on Dec. 25 and Dec. 29 covered most of the 200-meter-diameter summit crater. So, indeed it was larger than the current dome,” said Haney.
Given that the current lava dome is still significantly smaller than the dome in December, does that mean the explosion would be smaller if it happened from this smaller lava dome?
“No, a larger dome doesn’t necessarily mean a larger yield from the explosion,” said Haney. “We’re still expecting the same type of altitude for the ash cloud. It should interrupt Trans-Pacific Read more…
A 6.1 earthquake was reported in the Aleutian Islands near Alaska. The quake was reported at 8:10 a.m. HST (9:10 a.m. near the epicenter) on Wednesday, September 14, 2011.
The earthquake occurred at a depth of 1 km, according to the USGS.
Location to nearby cities is as follows: 21 miles NNW of Attu Station, Alaska; 596 miles E of Petropavlovsk-Kamchatskiy, Russia; and 2009 miles NE of Tokyo, Japan.
The NOAA West Coast & Alaska Tsunami Warning Center issued a statement this morning saying the magnitude is such that a tsunami IS NOT EXPECTED. However, in coastal areas of intense shaking, locally generated tsunamis can be triggered by underwater landslides.
The quake was initially reported to have occurred a depth of 6.2 miles, but the Geological Survey later updated its reading to say it was 22 miles deep.
The earthquake occurred 120 miles east-southeast of Atka, Alaska, in a sparsely populated part of the Aleutian Islands known as the Fox Islands. The epicenter was 1,658 miles west southwest of Anchorage, the Geological Survey said.
It prompted a brief tsunami Read more…
Storms can ravage coastal permafrost, as shown near the village of Kaktovik, Alaska.© Accent Alaska.com/Alamy
Gray waves surged over miles and miles of open water, breaking against the bluffs underlying Kaktovik. The tiny village sits precariously on the Beaufort Sea, a frigid body of water bordering Alaska’s northeastern Arctic coast. As the choppy waters inundated vulnerable stretches of shoreline, the surf carved deep chasms into the tall bluffs.
Torre Jorgenson, a geomorphologist working near Kaktovik, watched the storm boil up, shaking homes and boats for nearly two days in July 2008. Dramatic erosion followed soon after. Blocks of graphite-colored earth, as much as 10 meters wide and several meters deep, toppled into the sea one by one like skyscrapers in a Japanese monster film.
“The locals had never seen that type of erosion,” says Jorgenson, also president of the U.S. Permafrost Association. “It was something new, a regime change.”
The erosion Jorgenson witnessed was a potent warning to Kaktovik’s residents of the instability of their coastal home. Seaside bluffs and beaches across the Arctic are Read more…
Searching for food, one female bear was tracked as she swam for 9 days across the Beaufort Sea before reaching an ice floe. Litigation continues over protection of bear habitat.
In one of the most dramatic signs ever documented of how shrinking Arctic sea ice impacts polar bears, researchers at the U.S. Geological Survey in Alaska have tracked a female bear that swam nine days across the deep, frigid Beaufort Sea before reaching an ice floe 426 miles offshore.
The marathon swim came at a cost: With little food likely available once she arrived, the bear lost 22% of her body weight and her year-old female cub, who set off on the journey but did not survive, the researchers said.
“Our activity data suggests that she swam constantly for nine days, without any rest. Which is pretty incredible,” said George M. Durner, a USGS zoologist and a lead author of the study, published last month in the journal Polar Biology.
“We have observed other long-distance swimming events. I don’t believe any of them have been Read more…
SAND POINT, Alaska — A magnitude 5.9 earthquake shook several communities on the Alaska Peninsula, but there have been no immediate reports of damage. Krista Galvin is an administrative assistant with the city of Sand Point. She says it felt “like it just kept shaking, just longer than usual,” maybe lasting as long as a couple of minutes. She hadn’t heard of any damage, but said a school on top of a hill also felt an aftershock, which wasn’t felt in town. Sand Point is about 570 miles (917 kilometres) southwest of Anchorage. The U.S. Geological Survey reports the Tuesday afternoon earthquake was centred 25 miles (40 kilometres) south of Sand Point, at a depth of almost 22 miles (35 kilometres). It was also felt in Cold Bay and Chignik.