Washington State Emergency Management

Olympia, WA

Cascadia Rising Exercise 2016.

Active Volcanoes

Cascade Range

Active Volcanoes Cascade Range

Washington State Emergency Management

Olympia, WA

Volcanoes In Cascadia Range

Related Charts And Graphs

Juan De Fuca Plate

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Subduction Zone

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Movement & Velocity Chart

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California Earthquake Reputure Chart

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News Articles & Comparison To New Madrid Quake

Peninsulat Daily News

Port Angeles, WA

Geologist highlights faults
Potential Peninsula impact.

Penninsula Daily News Port Angeles
By Arryn Rice
Port Angles-The Cascaida Subduction Zone huge fault isn't the only mover and shaker residents need to worry about according to geologist Dan May The North Olmpic Peninsula is riddled with earthquake faults he says

No Building Can Withstand a 9 On Richter Scale

May who spends summers in Port Angeles told about 30 people at the Port Angeles Business Association on Tuesday morning that he began studying the Penninsula's geoology after he purchased property in Port Angeles, whee he eventually hope to live and wanted to now more about it's stailibty

The subduction zone fault can create hugh quake in the magnitude 9.0 range-which he says no building can withstand, no matter howgood the coes are, but i only strikes on the average of every 500 year, according to 2011 US Geological Survey report.The quake will geneate a tsunami that will reach in us 10 minutes" May said

Every place with a name with bay, canal or port is at risk" But such a quake isn't likely to happen in our lifetime of anyone living today in Washington state, said May, adjunct professor at Oklahoma City University of Oklahoma City. He thinks that more immediate concer to those living on the North Olympic Penninsula and dozens of other fault in the Strait of Juan De Fuca

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New Madrid Faultline

New Madrid FaultLine 1812
What Does 9 On Richter Scale Mean?

1811–12 earthquake seriesMain article: 1811–12 New Madrid earthquakes

December 16, 1811, 0815 UTC (2:15 a.m.); (M ~7.2 – 8.2[9]) epicenter in northeast Arkansas; it caused only slight damage to man-made structures, mainly because of the sparse population in the epicentral area. The future location of Memphis, Tennessee was shaken at Mercalli level nine intensity. A seismic seiche propagated upriver and Little Prairie was destroyed by liquefaction.[10] Local uplifts of the ground and water waves moving upstream gave the illusion that the river was flowing backwards.

At New Madrid, trees were knocked down and riverbanks collapsed. This event shook windows and furniture in Washington, D.C., rang bells in Richmond, Virginia, sloshed well water and shook houses in Charleston, South Carolina, and knocked plaster off of houses in Columbia, South Carolina. In Jefferson, Indiana, furniture moved and in Lebanon, Ohio, residents fled their homes. Observers in Herculaneum, Missouri, called it "severe" and said it had a duration of 10–12 minutes.[11]Aftershocks were felt every six to ten minutes, a total of 27, in New Madrid until what was called the Daylight Shock, which was of the same intensity as the first. Many of these were also felt throughout the eastern US, though with less intensity than the initial earthquake.[11]

The earthquakes were felt as far away as New York City and Boston, where ground motion caused church bells to ring.[12] Hundreds of aftershocks followed over a period of several years. Aftershocks strong enough to be felt occurred until the year 1817. The largest earthquakes to have occurred since then were on January 4, 1843, and October 31, 1895, with magnitude estimates of 6.0 and 6.6 respectively.

Cascadia Faults Chapter Day of Reconing-By Jerry Thompson

Caucadia Faults

By Jerry Thompson

Cascadia Faults
Chapter Day of Reconing-By Jerry Thompson

A very optomistic assessment of a major earthquake which reads as follows.. On a foggy spring monring just before sunrise, twenty-seven miles (43KM) northwest of Cape Mendocino, California, a pimple of rock roughtly a dozen miles (19KM) below the ocean floor finally reaches its breaking point. One the same thrust facture that rattled the towns of Petrolia, Fernadale, Eureka, and Arcata, two slabs of the earth's crust begin to slip and shudder and snap aparart as the cancadia's fault finishes what it started back in 1992.That day could be only ten years away. or two hundred years from now. Or it could happen tonight. And this is how I've imagined it will unfold.

On a foggy spring monring just before sunrise, twenty-seven miles (43KM) northwest of Cape Mendocino, California, a pimple of rock roughtly a dozen miles (19KM) below the ocean floor finally reaches its breaking point. One the same thrust facture that rattled the towns of Petrolia, Fernadale, Eureka, and Arcata, two slabs of the earth's crust begin to slip and shudder and snap aparart as the cancadia's fault finishes what it started back in 1992.That day could be only ten years away. or two hundred years from now. Or it could happen tonight. And this is how I've imagined it will unfold.

The first jolt of stress coming out of the rocks send a shockwave hurtling into northern California and southern Oregon like a thunderbolt- as the last time, only bigger. Ten time the magnitude and thirty-two more energy. For a few stunned drives on the back roads in the predawn glood, the pulse of energy that tears through the gound looks dimly like a twenty=mile (30KM) wrinkle moving through a carpent of pasturesand into thick stands of redwoods.
Telephone poles whip back and forth as if caght in a hurricane. Powerlines rip loose in a shower of blue and yellow sparks, falling to the ground where they writhe line snakes....go out and the telephone system goes down.

Cornices fall, brick walls crack, plate windows Seeing fragments of this happen through drifting shorounds of fog makes it hard for survivors to know hmuch is real, how much is their worst nightmare. With computers crashing and cell towers dropping offline, all of Humboldt and Del Norte Counties in California area instantly cut off from the outside world, so nobody beyond the immediate area knows how bad it is here or how widespread the damage is. Same for southern Oregon, Despite the risking sun everthing suddenly seems dark again. People living in the necklace of towns and villages along the coast are now officially on their own. No help will come any time soon.

On a spit of sand running down the western edge of the Humboldt Bay, an air raid sire wails as residents in the former sawmill town of Samoa, barely a dozen feet (e.6m) above sea level, bang through their doors-those that will stilll open, that not twisted out of true by the violent shaking of their homes-and run, walk, or stumble as best they can toward slightly higher ground near the water tower. They know from past drills that the first wave could hit the beach as quickly as eight minutes from the rupture.

As the USGS lab in Menlo Park semsmometers peg the quake at magnitude 8.1 and the tusunami detection centers in Alaska and Hawaii begin waking up the alarm system with stand-by alerts all around the Pacific Rim. High-rise towers in Sacramento begin to sway. Early morning commuters emerging from a BART station in San Francisco feel the ground sway beneath their feet and immediately hit the sidewalk in a variety of awark crouches, a familiar fear chilling their guts. The another little rought spot on the bottom of the continent snaps off. The fault unzips some more.

Back in Petrolia, where the ground has been shaking for more than a minute already, the street now heaves like a trawler's greasy desk in a North Pacific gale. The entire Gorda plate has come unstuck. The out edge of Californi snaps free like a steep spring in a judderling lurch nine feet (2.7m) to the west. The continental shelf heaves upward, lifting a mountain of seawaters.

The new shockwave, from the latest broken rought spot, slams from the Gorda into the Juan de Fuca place farther north-like gigantic train cars banging together-and thus the fault continues to rip all the way to Newport, Oregon, halfway up the state. The magnitude suddenly jumps to 8.6. A power surge blows a breaker somewhere east of town and feeds back through the system, throwing other brakes in a cascade of dominoes that quickly crashes the entire grid of Oregon, Washingtion, and parts of Califoria, Idaho, and Nevada. A brownout begins in six more western states. The wireless phone systems crashes in lockstep.

The the aspeerity benearh Newport shears away. The fault unzips the rest of the way to Vancouver Island, The quake now pins seismic needles at magnitude 9.2. A pineapple espress has deliverd a long sting of storms that are pelting rain from Cannon Beach all the way to the Queen Chralotte Islands. High-rise towers in Portland, Seattle, Vancouver, and Victoris begin un undulate. Cascadis's shockwave hammers through sandy soil, soft rock, and landfill like the deepest notes on a big string bass. The mush ground sings harmony and tall buildings hum like so many tuning forks. The earth rings like a fell as the three plates of crust find a new equilibrium.

On I-5 the main north-south interstate highway, thirty-seven bridges between Sacramento and Bellingham, Washington collapse, or are knocked off their pins. Five more go down between the canada-U.S. border and downtown Vancouver. The most vital overland lifeline from California to British Columbia is severed and bleeding badly. The Trans-Canada Highway has been cut in three places east of Vancouver. All the big bridges spanning the Fraser River in metropolitan Vancouver, around Pudget Sound in Seattle, and across the Columbia in Portland have been damaged. None has collapsed outright, but they are considereded unsafe until inspector teams can check them out. All major highways leading out of the big citiees are plugged with debris from toppled buildings, rockslides, and traffic jams.

Nineteen railway bridges along the north-south costal mainline of the Burlington Northern Santa Fe railways are wrecked as well. Boulders block the east-west mainline tracks of both the Canadian Pacific and Canadian National Railway systems. Three engines and twienty-nine chemical tank cars, at least half of them full of chlorine, detail and spill their deadly cargoes just outside Tacoma. Deep-sea shipping in docks in Portland, Seattle, and Vancouver sum and crack their pilings undermined by liquefaction. As miles and miles of dikes around the city of Richmond, Bright Columbia, turn to much the incoming tide sweeps inland, swamping much of the city.

The runways of every major costs airport from Northern California to Vancouver are buckled, cracked, and no longer flyable. An airbus on short-final at Sea-Tac touches down just as the concrete breaks. ... Sixteen emergeny care hospitals in Vancouver, Victoria, Seattle, and Portland-many of them built before the latest earthquake codes came into effect-suffer full or portial failure of load bearing walls........

Geology & Earth Resources

Washington State DNR
1111 Washington ST SE
MS: 47007
Olympia, WA 98504-7007

What Does "Super Quake Actually Mean?
& What Might Occur

Depend on what expert or source you consult that are 3 types of earthquakes which might occur. The large silent quake involves the plates moving by each other largely unnoticed. Another scenerio involves hundreds of smaller quake occuring and relieving the pressure on the plates. Lastly and the one we will consider is the super quake where the plate snap under massive pressure and generate a quake above 9 on the Richter scale.

Will Every Volcano In Cascades Will Erupt....
Emergency Management Structures First Casualties?

Tragically the State Emergency Management HQ at Camp Murry was 45 miles from the side of Mount Rainer which collapsed and released a massive slide of lava, mud, and gases knocking down trees 50 miles away. The EMD HQ is a permanent memorial and no plans exist to dig down and disturb the remains of he staff. The North American plate moved 30 feet or was it 30 years westward and the underground FEMA center is another national memorial.

Exploding volcanoes distributed massive amounts of volcanic dust which created massive electrical disturbances making radio and ham radio operations implaussible. Help wasn't really on the way since Stevens Pass and the passes along I-84 are blocked long term by massive rock slides which will take months to clear. Deceased emergency management officials never could find solutions for hundreds of bridges on highways which collapsed isolating many communities.

A 500 foot high Tsumani came ashore at Aberdeen Washington and surged half way to Olympia. A 2nd Tsunami occured in Lake Washington and apparently washed Bill Gates mansion into the lake along with waterfront from most cities joining the lake. Strangely enough officials in Eastern Washington whose communications and resources were largely unaffected in cities such as Spokane had no idea of who or what to contact in Western Washington. With the internet off line for some time someone recalled that a Chinese earthquake took out thousands of computer lines in 2007.

Everyone who can walk, drive, or crawl self evacuates towards Western Washington or Boise, Idaho where massive camps have to be established to take care of those who refuse to return home even months later.

Rising Coastline May Prove-Big One is Due"

Associated Press

Oregon State University

Rising Coastline May Prove
-Big One is Due"

More than 1,000 earthquakes occur in the state annually. Washington has a record of at least 20 damaging earthquakes during the past 125 years. Large earthquakes in 1946, 1949, and 1965 killed 15 people and caused more than $200 million (1984 dollars) in property damage. Most of these earthquakes were in western Washington, but several, including the largest historic earthquake in Washington (1872), occurred east of the Cascade crest. Earthquake histories spanning thousands of years from Japan, China, Turkey, and Iran show that large earthquakes recur there on the order of hundreds or thousands of years. Washington's short historical record (starting about 1833) is inadequate to sample its earthquake record. Using a branch of geology called paleoseismology to extend the historical record, geologists have found evidence of large, prehistoric earthquakes in areas where there have been no large historic events, suggesting that most of the state is at risk.

Geologic Settings

Washington is situated at a convergent continental margin, the collisional boundary between two tectonic plates. The Cascadia subduction zone, which is the convergent boundary between the North America plate and the Juan de Fuca plate, lies offshore from northernmost California to southernmost British Columbia. The two plates are converging at a rate of about 3-4 centimeters per year (about 2 inches per year); in addition, the northward-moving Pacific plate is pushing the Juan de Fuca plate north, causing complex seismic strain to accumulate. Earthquakes are caused by the abrupt release of this slowly accumulated strain.

Earthquake Types In Washington
Intraplate or Benioff Zone Earthquakes

Intraplate or Benioff zone earthquakes occur in the subducting Juan de Fuca plate at depths of 25-100 km. The largest of these recorded were the magnitude (M) 7.1 Olympia earthquake in 1949, the M6.5 Seattle-Tacoma earthquake in 1965, the M5.1 Satsop earthquake in 1999, and now the M6.8 Nisqually earthquake of 2001. Strong shaking during the 1949 Olympia earthquake lasted about 20 seconds; during the 2001 Nisqually earthquake, about 40 seconds. Since 1870, there have been six earthquakes in the Puget Sound basin with measured or estimated magnitudes of 6.0 or larger, making the quiescence from 1965 to 2001 one of the longest in the region's history.

As the Juan de Fuca plate subducts under the North America plate, earthquakes are caused by the abrupt release of slowly accumulated strain. Benioff zone ruptures usually have dip-slip or normal faulting and produce no large aftershocks. These earthquakes are caused by mineral changes as the plate moves deeper into the mantle. Temperature and pressure increase, and the minerals making up the plate alter to denser forms that are more stable at the increased temperature and pressure. The plate shrinks and stresses build up that pull the plate apart. For the February 28, 2001, Nisqually earthquake, the hypocenter, or point beneath the surface at which the rupture starts, was at 52 kilometers (32 miles). The area of rupture was approximately 30 kilometers by 10 kilometers (18 miles by 6 miles) and slipped approximately one yard. The epicenter was just off the Nisqually delta in Puget Sound. The quake was felt as far north as Vancouver, British Columbia, as far south as Salem, Oregon, as far east as Spokane, Wash., and as far southeast as Salt Lake City, Utah. Most of the damage was sustained in the Olympia and Seattle areas.

Shallow Crustal Earthquakes

Shallow crustal earthquakes occur within about 30 km of the surface. Recent examples occurred near Bremerton in 1997, near Duvall in 1996, off Maury Island in 1995, near Deming in 1990, near North Bend in 1945, just north of Portland in 1962, and on the St. Helens seismic zone (a fault zone running north-northwest through Mount St. Helens) in 1981. All these earthquakes were about M5–5.5. In Oregon, historically a low-seismicity state, crustal earthquakes have recently occurred just south of Portland (M5.7) and in Klamath Falls (M6.0). The largest historic earthquake in Washington (estimated at M7.4), the North Cascades earthquake of 1872, is also thought to have been shallow. It may rank as Washington’s most widely felt earthquake. Because of its remote location and the relatively small population in the region, though, damage was light.

Recent paleoseismology studies are demonstrating previously unrecognized fault hazards. New evidence for a fault system that runs east–west through south Seattle (the Seattle fault) suggests that a major earthquake, M7 or greater, affected the area about 1,000 years ago. Similar large faults occur elsewhere in the Puget Sound but have not been studied in detail.

Subduction Zone (Interplate) Earthquakes

Subduction zone (interplate) earthquakes occur along the interface between tectonic plates. Compelling evidence for great-magnitude earthquakes along the Cascadia subduction zone has recently been discovered. These earthquakes were evidently enormous (M8–9+) and recurred on average every 550 years. The recurrence interval, however, has apparently been irregular, as short as about 100 years and as long as about 1,100 years. The last of these great earthquakes struck Washington about 300 years ago.

How Earthquakes Cause Damage

The principal ways in which earthquakes cause damage are by strong ground shaking, by the secondary effects of ground failures (surface rupture, ground cracking, landslides, liquefaction, subsidence), or by tsunamis and seiches. Most building damage is caused by ground shaking.

Ground Shaking

The strength of ground shaking (strong motion) generally decreases with distance from the earthquake source (attenuation), but locally can be much higher than adjacent areas, due to amplification (an increase in strength of shaking for some range of frequencies). At the same time, there is a decrease, or deamplification, in strength of shaking for other frequencies. Amplification occurs where earthquake waves pass from bedrock into softer geologic materials such as sediments. Strong shaking of long duration is one of the most damaging characteristics of great subduction zone earthquakes. Strong shaking during the 1964 Alaska earthquake lasted about 90 seconds with an additional 90 seconds of strong ground motions still of alarming magnitude, followed by swaying and shaking a little. The total time of shaking was about 3 minutes 40 seconds. Strong shaking is a hazard both near the epicenter of an earthquake and in areas where amplification occurs. West Seattle and certain areas of downtown Olympia are examples of places where ground motion has been documented as being significantly stronger than in adjacent areas during the same earthquake. The extensive damage to the Cypress Structure viaduct in Oakland, California, was a classic example of strong ground motion damage during the M7.1 Loma Prieta earthquake of 1989. Most of the damage and deaths in earthquakes are caused by strong ground motion.

Ground Failures

Ground failures accompanying earthquakes include fault rupture (surface faulting), ground cracking, subsidence, liquefaction, and landslides. Fault rupture occurs as offsets of the ground surface and is limited to the immediate area of the fault. Other ground failures can occur over a wide area and can have several causes. Landslides, including debris avalanches from volcanoes, have been caused by earthquakes. Earthquake-induced acceleration can produce additional downslope force, causing otherwise stable or marginally stable slopes to fail. In the 1964 Alaska earthquake, for instance, most rockfalls and debris avalanches were associated with bedding plane failures in bedrock, probably triggered by this mechanism. In addition, liquefaction of sand lenses or changes in pore pressure in sediments trigger many coastal bluff slides. Rockfalls, such as those that caused two deaths in the 1993 Klamath Falls earthquake in Oregon, can be triggered at great distances from earthquake epicenters. Liquefaction occurs when water-saturated sands, silts, or (less commonly) gravels are shaken so violently that the grains rearrange and the sediment loses strength, begins to flow out as sand boils (also called sand blows or volcanoes), or causes lateral spreading of overlying layers. Ground failures, such as ground cracking or lateral spreads (landslides on very shallow slopes) commonly occur above liquefied layers. Noteworthy liquefaction took place in Puyallup during the 1949 earthquake. The sands that failed in many cases were sand deposits from Mount Rainier debris flows; similar hazards could be expected in other valley floors downstream from other stratovolcanoes, such as Mount Baker, Mount St. Helens, and Mount Adams. Subsidence (including differential ground settlement) can result in the flooding and (or) sedimentation of subsided areas, as occurred over broad areas in Chile (1960) and Alaska (1964)

Tsunamis and Seiches

Tsunamis (seismic sea waves) are long-wavelength (large distance between wave crests), long-period (several minutes to several hours between wave crests) sea waves that can be triggered by earthquakes or by landslides into a body of water. These are erroneously called tidal waves even though they are not caused by tides because they are sometimes preceded by a recession of water resembling an extreme low tide. Tsunamis are more damaging when they strike a coastline that has suffered earthquake-induced subsidence. Seiches resemble tsunamis but occur as standing waves (or sloshes) in enclosed or partially enclosed bodies of water.

Can Earthquakes Be Predicted?

Many precursors to earthquakes have been studied in the hope that they will allow us to predict the size, location, and time of an earthquake, all of which must be accurately predicted simultaneously to be useful in preparing for and responding to earthquakes. Some of the precursors studied are small magnitude earthquakes, water levels in wells, concentrations of radon and helium in ground water, changes in natural electromagnetic radiation, and animal behavior. Psychics and amateur scientists frequently claim (without verification) to be able to predict earthquakes. However, as yet, none of the precursors or other prediction methods have been consistent. Consequently, in the United States, more effort is directed toward understanding earthquake sources and effects than toward prediction.

Prepared by Timothy J. Walsh, Wendy J. Gerstel, Patrick T. Pringle, and Stephen P. Palmer Washington Division of Geology and Earth Resources