Showing posts with label anchorage. Show all posts
Showing posts with label anchorage. Show all posts

Wednesday, April 14, 2010

More on Earthquakes

http://www.examiner.com/x-/x-28964-Anchorage-Conservative-Examiner~y2010m1d24-Alaska-Earthquakes-Volcanoes-and-Tsunamis

Alaska: Earthquakes, Volcanoes, and Tsunamis

January 24, 12:26 PMAnchorage Conservative ExaminerFranke Schein
3 comments Subscribe
1964 Alaska Earthquake
1964 Alaska Earthquake
Photo: www.infoplease.com/

In the wake of the severe earthquake that savaged Haiti, one must remember that Alaska faced a similar catastrophe in 1964.


Lasting nearly five minutes, it was the most powerful recorded earthquake in U.S. and North American history, and the second most powerful ever measured by seismograph. It had a magnitude of 9.2, at the time making it the second largest earthquake in the recorded history of the world.

131 people lost their lives in the earthquake, and thousands were left devastated throughout much of the areas hardest hit.

A large tsunami that reached 70 feet high, and travelling at 450 miles an hour slammed into Alaska’s coastline—flooding much of the areas and creating rockslides that resulted in massive property damages. Vertical displacement of the land rose to approximately 38 feet.
Girdwood and Turnagain Arm, were destroyed by subsidence and subsequent tidal action, and 20 miles of the Seward Highway sank below the high-water mark of Turnagain Arm effectively cutting off the southern road system.

[ Alaska Earthquake March 27, 1964. Earthquake-demolished home in Turnagain Heights in Anchorage. 1964. Image file: /htmllib/batch75/batch75j/batch75z/ake00368.jpg ]

Following the initial earthquake there were approximately 10,000 aftershocks. Eleven major aftershocks were recorded on the first day alone with a magnitude of 6.0, and nine more occurred over the next three days. The earthquake’s aftershocks continued for another eighteen months.
The question that one must ask is will it happen again?

In a book titled “We are the earthquake generation” written in 1978 by Jeffrey Goodman, PHD; details startling facts that point to several distinct phenomena that could trigger another Alaska earthquake.

In one of the hypotheses Goodman concludes that the earth has a bulge along its equator. The circumference of the earth is 27 miles greater around the equator than around the poles. It’s thought that a large accumulation of ice on either pole would be enough to destabilize the earth’s spin, and unbalance it enough to cause the massive tectonic plates to shift—thereby resulting in mega-earthquakes and tsunamis, as well as eruption of several volcanoes within the region.
He also points to other causes that contribute to earthquakes—such as off shore drilling, nuclear weapons discharges, volcanic eruptions, and lowered water levels in the ground that could be the catalysis for future earthquakes.
Considering that Anchorage is the central hub where all of the cargo and supplies are distributed throughout Alaska, the ramifications of another severe earthquake would have potentially devastating effects on the rest of the state.
During the 2009 Mt. Redoubt eruption, most of the air traffic into and out of Anchorage was cancelled because of the volcanic ash threat it posed to commercial aviation. Alaskan’s were stranded in Seattle and Portland awaiting flights to Anchorage, some waited for days until a flight to Fairbanks brought them closer to home.
Alaska is one of the most active volcanic areas on the globe. The Aleutian islands have more active and dormant volcanoes than any other place in the world—and they are prone to earthquake activities.
Should another large earthquake shake the region, it’s possible that one or more volcanoes might erupt. Tidal waves, ash filled skies, and destroyed roadways would wreak havoc on Alaska’s ability to respond to a catastrophe of this nature.
Alaska is one of the most isolate states in the country. Nearly everything that is needed for consumption is either flown in, or brought in by trucks or barges. Any disruption of these vital supply routes will have instantaneous results on critical infrastructure such as fuel distribution, food, and other consumer goods.
Having the foresight to stockpile emergency supplies is almost critical to Alaska’s families. Should another earthquake strike alaska, like it did in 1964, the consequences could be devastating.

Photo: http://pixdaus.com/single.php?id=40289 Downtown Anchorage after the 1964 Earthquake

In a future article I will discuss the Pole Shift theory; another phenomena that could trigger earthquakes and volcanic eruptions.
Associated Press - January 24, 2010 4:54 AM Earthquake rattles near several towns

Tuesday, April 13, 2010

constant instability in alaska


http://newsminer.com/view/full_story/7054628/article-Alaska-s-Redoubt-volcano-stops-shaking-?instance=home_news_window_left_bullets
Alaska's Redoubt volcano stops shaking
by The Associated Press
6 hrs ago | 239 views | 0 0 comments | 1 1 recommendations | email to a friend | print
ANCHORAGE, Alaska - The swarm of small shallow earthquakes that began April 5 at the Redoubt volcano has ended, and the shaking returned to background levels.

The Alaska Volcano Observatory lowered the aviation code Monday from yellow to green.

Eruptions from the 10,197-foot volcano early last year disrupted air travel, dusted Anchorage with ash and sent a mudflow that partially flooded the Drift River Oil Terminal.





just thought it was interesting that the volcanoes that seemed so distant from the city have such a drastic effect.

Tuesday, April 6, 2010

Quakes near Anchorage

ANCHORAGE, Alaska — A swarm of small earthquakes began Monday at a volcano near Anchorage in what scientists said was a warning that Mount Redoubt could be waking from its slumber.

"It is reminding us that it is an active volcano," said Rick Wessels, a geophysicist with the U.S. Geological Survey in Anchorage.

The swarm of small quakes started early in the day near the summit of Mount Redoubt, about 100 miles southwest of Anchorage, with a regular pattern often seen when magma is moving inside a volcano, Wessels said.

Researchers plan to fly through the steam plume of the volcano later this week and take measurements of three chemical compounds linked to volcanic activity — sulfur dioxide, carbon dioxide and hydrogen sulfide.

Scientists do not know if the earthquakes will lead to the volcano again becoming explosive, but they said that was a heightened possibility.

Last year, the volcano rumbled and grumbled for months before exploding on Jan. 26, at times producing huge ash plumes and sending mud flows down its flanks. It finally quieted in late September, but there was a similar episode of increased seismic activity in December.

Then came Monday.

"We were going along quietly and all of a sudden, boom, we started getting these small earthquakes," said Steve McNutt, a University of Alaska Fairbanks research professor.

Mount Redoubt is monitored by seven seismometers.

Last year, Mount Redoubt awoke after a magnitude-5.7 earthquake at the mouth of Cook Inlet.

The volcano followed that period of unrest with 19 significant eruptions over several weeks in March and April in which it sent ash plumes as high as 65,000 feet and cloaked parts of south-central Alaska in up to a half-inch of ash.

Residents donned face masks and covered their cars and trucks to keep the ash off the finish and out of the engines.

Mount Redoubt also erupted in 1989 and 1990.

Wessels said the current earthquakes were not connected to Sunday's magnitude-7.2 quake in Mexico just south of the U.S. border.

"We wouldn't expect there to be any connection given the distances," he said.

Alaska is the most seismically active state in the country. In 1964, it experienced a magnitude-9.2 earthquake near Anchorage, the strongest earthquake ever recorded in North America.

Sunday, February 21, 2010

Earthquake in Alaska




USGS reports small earthquake in Southern Alaska

Associated Press - February 21, 2010 12:24 PM ET

ANCHORAGE, Alaska (AP) - A minor earthquake has struck north of Anchorage, but no injuries or damages have been reported.

The U.S. Geological Survey says the quake, with a 3.0 magnitude, hit at 7:28 a.m. Sunday, and it was centered 24 miles north of Anchorage and 1 mile outside the town of Big Lake.

The USGS also says people in Eagle River and Chugiak have reported feeling the quake.

Copyright 2010 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
AddThis Social Bookmark Button

Sunday, February 7, 2010

Anchorage GIS

Link to GIS on Anchorage, AK:

CLICK HERE

(must use Internet Explorer to view)

Saturday, February 6, 2010

Anchorageans(?) for a healthier community

Highway designer, urban planner, Lynn Peterson, talks the walk

http://www.adn.com/money/story/1123581.html


Her 2009 video presentation can be found here:

http://www.clackamas.us/bcc/peterson/alaska.htm

Monday, February 1, 2010

Environment or Economy?

Apparently a Republican representative from Anchorage believes the economy trumps the environment.

Press Release - Holland America

Here's the press release Holland America sent out on bringing a ship to Anchorage for the first time.

http://www.hollandamerica.com/news/NewsRelease.action?newsReleaseId=712

Sunday, January 24, 2010

Time Lapse Bore Tide

Here's a time lapse video of the bore tide mentioned in class on Fri.:



Here's another video of the bore tide along coming in along the coast. (Embedding disabled)

http://www.youtube.com/watch?v=DA8Ekia_75o


And some tidal bore surfing (a favorite Alaskan past time):


Monday, January 18, 2010

Alaskans drink beer?

No more bear maulings... That's a plus!

Quiet year for Anchorage bears after maulings of 2008

RARE: Officials had no reports of chasing or charging bruins.

Where did all the bad bruins go?

One summer after grizzlies swatted, chased and seriously mauled three people in the municipality of Anchorage, residents again this summer were hiking, biking and recreating in the great outdoors. The difference: they weren't being harassed and attacked by bears.

"I don't recall having any calls about close encounters this summer," said Rick Sinnott, an Alaska Department of Fish and Game biologist -- the same person who got an earful last summer from city residents after three people were mauled by grizzlies, two of them while using a trail in a city park.

In a typical summer, one or two people will report they have had a close encounter with a bear in Anchorage, but not this summer, Sinnott said. Not only have there been no maulings but he hasn't received any reports of people being charged or chased by bears.

"It is a little quieter than usual," he said.

Officials don't know for sure why it was an encounter-free summer, but point to better education of humans, increased use of bear-resistant garbage cans and fewer salmon running in city streams as possible causes.

Whatever the reason, it's a lot quieter than last summer when badly behaving bears had city residents joining two emotionally charged camps: those who wanted all the bears killed and those who wanted them left alone. Most residents wanted something done but weren't sure what.

The din to do something grew after a 15-year-old girl in a bike race in Far North Bicentennial Park was mauled by a grizzly and nearly bled to death. The call to action got louder when a middle-aged runner was attacked by a grizzly on the same trail.

Residents living outside the city proper weren't immune to bad bear behavior. A man in Eagle River, about 10 miles north of Anchorage, was walking home one evening when he ended up boxing a brown bear. He was injured in the encounter but escaped with his life. Ask him and he says he won the fight.

"It was just a weird year for brown bear incidences," Sinnott said.

This summer was eerily quiet compared to last summer, but wildlife officials say from their perspective it was a more normal summer.

"In the past, prior to last year, there would be an occasional sighting of a bear's behind going across the trail or scat on the trail," said John McCleary, recreation superintendent for Anchorage Parks and Recreation. "That is what I call normal."

The only bear-mauling deaths to have occurred in the municipality were in July 1995 when a mother and son were killed by a bear defending a moose carcass along a trail.

Sinnott said human behavior may have changed this summer in Anchorage. Fewer cars have been parked at Far North Bicentennial Park where the two women were attacked last summer on Rover's Run trail. The trail, which runs next to a salmon stream, was closed in early June to reduce the chances of people encountering hungry bears. It remains closed but may be reopened now that cold weather and winter is on the way.

McCleary said park usage appears to be getting back to normal.

Killing the bear that attacked runner Clivia Feliz probably did the most to quiet things this summer, Sinnott said. An analysis of DNA found in saliva and hair revealed it was the same bear, also believed to have chased and charged other park users. The sow's two cubs were sent to the Indianapolis Zoo.

"Part of it was one brown bear sow with her two cubs that was in the wrong place at the wrong time -- from a human perspective -- and was willing to take protection of her cubs to the limit," Sinnott said.

The DNA test determined that it was not the bear who committed the most serious attack of the summer when Petra Davis' carotid artery was partially severed and her trachea crushed during the bike race.

Removing the troublesome sow also didn't explain why the Eagle River area was quiet this summer after Devon Rees was attacked last summer. There also were numerous reports of people being charged by perhaps a second grizzly in the town, Sinnott said.

Maybe the bear "wasn't in the mood" or moved on, he said.

"I don't know," Sinnott said.

Organizers of Anchorage's "Bear Aware? Know Before You Go" program said thousands of people received education this summer on how to avoid bears and what to do if you encounter one. Activities included bear know-how games for children and bear clinics for adults.

After last summer, some residents were afraid to enjoy the city parks, said Elizabeth Manning, education and outreach specialist for Fish and Game.

"We have just been trying to arm people with as much education and information so they can get over that fear," Manning said.

The increased use of bear resistant trash cans by residents also may be making a difference, Manning said. Use is up from about 150 cans a couple of years ago to about 800 now.



Wednesday, January 13, 2010