Alaska Earth Quake

September 16, 2008 3:29 PM | Alaskan Photo Tours

alaska earth quake

If Puget Sound is falling

William Steele, the Seismology Lab Coordinator at the University of Washington Geophysics Program, has a son, Chris, who goes to primary school. "He comes sometimes and she likes to do things." It seems that he had recently presented a sticker on one of the monitors in the laboratory and his father had some trouble accessing the equipment. "What an excuse!" Steele never did get into the program he had wanted to show.

December 4 last year there was a 5.1 magnitude quake in Klamath Falls, Oregon. The aftershocks were felt in Washington State. I had gone to the University of Washington in search of information on recent earthquake activity in the Puget Sound region.

"Oregon is relatively quiet with Washington. But this years, we had a tremendous amount of activity in Oregon, against the patterns of the past. "Klamath Falls could not be more noisy, Steele said, marking the Numbers: September 4, 5.9; September 1920, 5.9, 5.0, 4.3, December 04, 5.1, and on Christmas Day, 4.0, 3.4.

Most of our local activity in the Puget Sound is recorded by the UW computer lab. They have an emergency preparedness computer program called "Beat the Quake" coming from the land of earthquakes, California, which has suffered considerable damage caused by severe earthquakes lately. That's the program had problems running Steele on your computer. Fortunately, the UW Seismology Lab has a lot more information about emergency preparedness "so you do not have to start from scratch" in the likely event of an earthquake. Steele is also the Public Information Officer covering earthquakes through the University of Washington. "We have 135 seismic stations throughout Washington and Oregon, currently operating, and we are expanding. Really cover a wide area. "

They locate earthquakes precisely, then determine the magnitude (amount of total energy released by the quake), location (area affected by the earthquake) and the epicenter (location on the surface directly above the focus, or where an earthquake originates.)

They collect data about the geology of the region as well. "It is information critical. This lab is an educational center for graduate students in geophysics. "Educate citizens also. The school groups to bring students and Steele speaks at civic organizations, encouraging people to take action and be safer from earthquakes.

Of course, the big question everyone asks, "When?"

"We can not set a date. It is more complicated because three types of earthquakes occur in the Puget Sound region. The most common are earthquakes deep.

"The signals travel through the planet's crust, sometimes all the way from the other side." Events of any part shown in helicorder their leaves, making an analogy, a 24-hour record of each earthquake. For example, the Klamath Falls earthquakes, which are very close to California on the coast of Oregon.

"We cover the Cascade Range, and have several stations on all the volcanoes. We have a good season on the mountain. Baker, adequate to cover the region. "Earthquakes around volcanoes are common.

The contributions of laboratory data for California earthquakes occurring in California and Oregon border. "We are part of the Washington Regional Seismic Network." Steele showed me a map of seismicity of the Pacific Northwest, 1969-1991. There were huge blue clusters in Puget Sound. What are these, I asked. "Moderate, shallow and deep earthquakes. The clusters are deep in the Puget Basin."

deep earthquakes, those that do tend to write home about, are the largest in magnitude as measured on the Modified Mercalli Intensity Scale. The values vary widely between 1.0 (no sense) to 7.0 (extreme damage to buildings and land surfaces). They may rise further, as has happened in recent deep earthquakes in Alaska.

This is what is happening in Puget Sound: about 300 miles or more from the coast is where deep earthquakes are generated. There is a ridge 500 to 700 kilometers was called Juan de Fuca Ridge, and the new material, new sea floor is deposited all the time over it. Pushing the Juan de Fuca plate to the board of America below the North Seattle area. The Juan de Fuca plate moves an average of two inches a year, towards us, lifting the other plate.

A zone border that encloses an interface between the two oceanic plates that stops the plate, so it is Subduct beneath us, forcing the oceanic plate in the mantle of Earth. This limit is called the Cascadia subduction zone, and extends from the center of Vancouver Island in British Columbia to northern California.

The Earth's mantle lies beneath their fragile bark. It is semi-solid, due to the tremendous heat and pressure. "Our Cascade volcanoes are probably there because the subducting plate beneath us. The pressure deforms the crust and accumulate enormous stress. At this time, the Washington coast is increasing. It is swollen up. "The oceanic plate is" stone cold "and the shock of the meeting of two forces leads to deep earthquakes. Washington has recently suffered two large, in 1949 and 1965.

A laboratory brochure states that approximately 1,000 earthquakes a year are recorded in Washington and Oregon. "Between one and two dozen of these Earthquakes cause to be felt by residents. Most are from the Puget Sound region, and cause little real damage. However, based on the history of past strong earthquakes and our understanding of the geological history of the Pacific Northwest, we are confident that the damaging earthquake (magnitude 6.0 or greater) is repeated in our area, although we have no way to predict if this is more likely to be today or years from now. "Steele believes it will be soon.

"In 1949, there was a strong earthquake in Olympia, 7.1. Eight people were killed and millions of dollars in property damage. The quake was centered 70 km deep.

"In 1965, there was a magnitude 6.5 quake between Seattle and Tacoma." Both earthquakes were felt as far away as Montana. But there were no aftershocks, as is customary during an earthquake deep. The infamous replicas, known to catch people in the middle of recovering from a bad earthquake will occur during terrestrial surface earthquakes. The clashes occurred in the oceans once, causing tremors that lasted several minutes. "The earthquake killed about 1965 to five people, and again there was millions of dollars in property damage. "Other events deep, difficult to estimate from records of the times, occurred in 1882, 1909 and 1939. "Every 35 years or so an earthquake of magnitude 6.0 occurs below Puget Basin. The whole region along the coast will move at a time. When she finally builds up enough pressure to kick, going to be great. "

Eighty percent of the world's earthquakes occur along the Pacific Northwest ass, which is known as "The Ring of Fire" because of our entire volcanic activity. In 1964, a year before the last big event in this area, south-central Alaska created a monster 9.3 earthquake shaking the ground for twenty minutes, generating tidal waves that decimated the coast of Seward, affected 34 000 square miles, killing 143 people. And there have been recent major earthquakes in Cape Mendecino, California, and Parkfield, California, notorious for earthquakes, in 1992.

Brian Atwater of the USGS (United States Geological Service) and the UW geology department has studied along the coasts of Washington and Oregon. It type of soil found in layers … "What we found … ghost forests killed by the great earthquake happened. Subduction zone material covered by the black gravel." A layer gradually turned into forest floor and then the sand layer. "As you continue jumping, the high cost and low-lying areas are flushed clean with salt water. Stress is released during the earthquake causes the coast disappear for seven to eight feet. It drops. "If you live within five feet above sea level, is not a comfortable thing. "

Earthquakes also generate large tsunamis, or tidal waves, the largest, generated by large earthquakes, can rip a whole mile coastline, destroying bridges, roads and buildings. The really big earthquakes in subduction zone, 9.0 or more, only occur once per century in the face of the planet. Interestingly, a major earthquake could result in only about three and a half minutes worth of strong ground shaking, which does not sound like much. "A recent earthquake in California was only seventeen seconds of strong ground motion, an earthquake of 7.1. A 7.0 earthquake releases the equivalent of 199,000 tons of TNT in energy, a reported 200 million 9.0 tons or the equivalent to 17,000 atomic bombs "of force.

"The difference between 8 and 9 is greater than the difference between 2 and 8, due to logarithmic scale. The force increases exponentially. It gets 30 times more each time. "I wondered if it ever goes up to 10.0.

By carbon-14 dating of material organic soil and sea levels, "scientists can determine the approximate dates of events going back 10,000 years." Search clues about these earthquakes involves both careful research and conjecture.

Research has recently identified a fault which generated Seattle large quake between 1,000 and 1,100 years ago. "There were landslides, and a huge seiche, when something big falls in the water, creating waves like tsunamis. Great landslides block of land occurred in the forests. Restore Point on Bainbridge Island grew six meters in Puget Sound in seconds during that event. "

Accumulation glacial ice sheets once covered the continent make it difficult to analyze shallow crustal faults. But geologists are pretty sure that there are two big mistakes of Seattle. The largest extends from the northern tip of Mercer Island Eastgate through the Kingdome, just north of West Seattle. The other fault runs through White Center, parallel to the largest. In 1872, an estimated 7.3 shallow earthquake caused what seismologists call "felt reports" of observers, the only evidence of some major earthquakes. Native Americans have legends about what must have been some very major earthquakes and tsunamis.

Today, all telemetry (real-time automatic data transmission from a distant source to a receiving station) is noted in the back of the lab, where I poured a cup Steele Starbucks coffee its metal sink in a very crowded equipment. "Energy Relays zap" the activity in nanoseconds to the lab. Before people a region know what is going to hit, what we do. "The helicorders monitor 23 stations in analog." We focus on volcanoes. All stations, including helicorders those, go into the computer system in the next room. The discriminator on the back takes FM carrier signals and separated signals seismic seismic leaving an amplified signal. She goes to the front room, change into digital information the computer can read.

"If it contains a "jump" (a container in the needle into the helicorder) in a season, check other stations and records all data, if a signal or not. If This is a major earthquake, magnitude estimates made through programs, etc., ringing the people (like Steele), and sends information to seismologists in the region. "Steele might hear a" beep "at any time.

As I drank my coffee, I said Steele is a graduate student, works of life partner, and keep your family together, rent a house in Wallingford and raising two children. "It's a rewarding job, but … the rewards are not monetary." Without however, he feels treated as a colleague by all, and has a good working relationship with all of its peers in the laboratory. "

On the preparation for earthquakes, Steele is adamant. "The secret is not fear and loathing in Seattle, and we have to hide under the beds. We'll be ready." Our schools must reach the point where it can withstand an earthquake of 7.4. How many bricks little bodies do we need before you start spending some money? "At this point, no definite laws enforcing earthquake building codes, "If years ago the building code said you could pile of bricks without mortar at the top of the other. "

unreinforced masonry structures that fall creates even during moderate earthquakes. "The entire wall of a school may fall and kill students. A brick that falls three stories does not slow down, "he said, referring to the death of a child during the 1965 earthquake. Steele is safe these deaths preventable.

At least six schools in Oregon are non-reinforced structures, which can drop the bricks and fill a doorway, blocking the exit. "Retrofit them or tear them down and build another school. If a school has been deemed unfit for an earthquake of recent times, selling it, and becomes a center for the elderly. No law to stop that. These buildings should be educated in the code or down. The deaths will happen unless we act. India just had an earthquake measuring 6.8 … tens of thousands of dead. There is need for food and water stored to last 72 hours. You have to be under a table and ride it out, get down on the ground, under something, check to see if you smell gas, and off, electricity, too. "

You must know your community resources, Steele said. And in case of severe aftershocks, if you are in a building "should wait until the shaking stops, then leave." Many people are killed by falling debris during evacuation buildings.

The number of FEMA (Federal Emergency Management Agency) in Woodinville, led by Chris Trisler, is (206) 487-4645. It's your job to help people with earthquake preparedness.

Steele What to see in the near future? "I expect more of the same. Probably some earthquakes exceeding 4.0 on the area Puget Sound. Although we have been talking, I have not been made in Klamath Falls. "As I write this, there are 4 replies to this December" sequence "from Klamath Falls. "The question is, are we to recognize danger and do something about it, or we wait until we have an adequate number of dead? I'd like to see a dedicated plan and some leaders of the state. It will be a lot of money. "

Steele said one colleague said it best: "The next big disaster happen as soon as we forget the past. "

Some of the information in this article is "Washington State Earthquake Hazards" by Lawrance, Qamar, and Thorsen, 1988).

WHAT TO DO THAN SCREAM YOUR LUNGS OUT – Drop!

Apparently you can hear a very loud voice, sound building before the madness begins. The below is from "How to Survive in Earthquake," a brochure from FEMA. Know your risks at home and in your workplace. Get more details from the American Red Cross or FEMA.

Learn what causes injuries, the fall of external parts of buildings and interiors, pieces of flight of broken glass, tipping bookshelves, unanchored water heaters, storage facilities, anything made of glass, the burning of gas lines damaged, power lines, wood stoves, fireplaces, toxic smoke.

Create an emergency preparedness plan: finding safe places at home, identify escape routes, plan two ways out of each room, choose two places to meet outside your home and outside the neighborhood if can return to their homes, show everyone how to turn off water, gas and electricity; implement their plans now.

Read "The Family Disaster Plan" and "Checklist for Emergency Preparedness, which can be obtained from FEMA.

Reducing earthquake risks: assess your home heaters water and gas appliances strap down, recalls, supplement rigid elements, place heavy objects on low shelves, all that heavy anchor, anchor hanging objects; community support preparing for earthquakes.

Businesses, schools, daycare centers, neighborhoods, churches, clubs: Talleres out. Prepare a preparation team Disaster: storing food, water, clothing, first aid kit, a radio, flashlights and batteries, good for 72 hours of use, in your trunk of the car, home and office. For more details, see the FEMA booklet, "family disaster supplies kit."

During or after an earthquake: stay calm do not panic or run. Earthquakes are usually preceded by loud sounds, so take quick action. You actually have about two seconds, so get ready for the earthquake now to protect yourself and others. Stay where you are: duck, cover and hold something solid, or have immediate cover under a heavy desk or table in a doorway, hallway, or against inside walls. Stay away from glass. Stay away from fireplaces, windows, shelves high, and falling objects.

Evacuate only after the shaking stops. Use the stairs, no elevator. Remember, aftershocks may occur in any time. Listen to radio or television for instructions. Outdoors: Move away from buildings, trees and utility wires. Sit on the floor to the shaking stops. Escape routes immediately when near a coastline. Check for injuries. Do not move seriously injured persons unless they are in danger. At home: evacuate damaged buildings, as aftershocks could cause additional damage or buildings can collapse.

Do not reenter a building until is declared safe by authorities. Do not use the telephone except for emergencies, to stay off the phone. Check for fires. Keep a fire extinguisher, and how to use it. Check utilities: gas, electricity and water lines may be broken. Gas: Do not use matches, candles, open flames or indoor switches electrical, due to possible gas leaks. If you smell gas, open windows, exit, and turn off the main gas valve, which is outside.

Electricity: If the cable breaks, turn off electricity at main switch. Do not touch anything near downed or damaged lines. Water: If water pipes are broken, Turn off the main valve outside. Use water ice cubes, water heaters, toilet tanks (if they do not contain chemical cleaners). Wipe up spills. Carefully attend to spills of potentially harmful materials such as medicines, drugs and household cleaners. Provide ventilation appropriate, such as chemicals can be combined to produce the toxic gas. Remember to help others in need.

And remember: no fault yours. (Sorry, could not resist the joke.)

About the Author

Executive Director and President of Rainbow Writing, Inc., Karen Cole writes. RWI at http://www.rainbowriting.com is a renowned inexpensive and affordable professional freelance writers, book authors, ghost writers, copy editors, proof readers, coauthors, manuscript rewriters, graphics and CAD, digital and other photographers, publishing assistance and screenplay writers, editors, developers and analysts service.

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