A pair of scientists with the U.S. Geological Survey first theorized that a fissure between two major blocks of the earths crust might run through this slice of Puget Sound. At a downtown coffee shop, the mugs begin to chatter. Consider subscribing to our blog, Washington State Geology News, to receive notifications when new information is published. Photo from, This image shows the how the 1700 AD tsunami from the Pacific Northwest crossed the Pacific Ocean. Seconds later, its as if Whidbey Island is trapped in a cocktail shaker, lurching back and forth. Tsunami waves can travel over 500 miles per hour in the open ocean. Everything points to one thing, Sherrod said, waving his hand across the inland sea. In much of Washington, dense vegetation covers the land and makes finding faults very difficult. Larger crustal faults, such as the Seattle fault and southern Whidbey Island fault zone, can produce earthquakes up to magnitude 7.5. Most are too small to be felt or cause damage. Earthquakes occur nearly every day in Washington. Sherrod says practically every place they. Notice the Seattle Fault Zone bounding the Seattle Basin to the south. Stop as quickly as safety permits and stay in the vehicle. A 2014 map shows what we know about the age of faults in Washington. (360) 678-5111 Photo by G.K. Gilbert, from the Steinbrugge Collection of the UC Berkeley Earthquake Engineering Research Center. Since about 1870 there have been about 15 large earthquakes (greater than M5) in the state. x\[s8~OU)! Earthquake Hazards - Maps | U.S. Geological Survey After the earthquake, many things you count on may not be available. Within this rich oral history there are many references to events like earthquakes and tsunamis. Whidbey fault quake potentially a bigger 'Big One' We use the term deep to talk about faults and earthquakes deeper than about 18 miles. Walsh said that Whidbey Island through the years has been subjected to a number of small quakes, roughly 2 or 3 on the Richter scale. The Cascade block to the northeast is floored by diverse assemblages of pre-Tertiary rocks; the Coast Range block to the southwest is floored by lower Eocene marine basaltic rocks of the Crescent Formation. Stratigraphy in the Flying Squirrel trench showed gentle warping of late glacial and post-glacial sediments; no faults were exposed. 2 0 obj Ground shaking is a hazard near the epicenter of an earthquake and also in areas far from the earthquake where amplification occurs. The shaking can damage or destroy buildings and other infrastructure. Although we cannot predict exactly when the next earthquake will happen, we can predict the general distribution of earthquake sizes. An increase of 2 means that ~1,000 times more energy is released. These cookies will be stored in your browser only with your consent. Seattle Fault - Wikipedia Trenches by Sherrod and others, 2008 #7652) are less than 1 km south of KP1 and KP2 and Sherrod and others (2008 #7652) conclude that deformation in the area is due to surface-rupturing earthquakes. Do you live or work near an area that could have liquefaction? You can look at different geological hazard mapson the website of the Department of Natural Resources. In the 1990s, scientists producedan animationthat shows inundation, and people wont have much time to run to higher ground. The most recent hit roughly 2,700 years ago. These fault strands follow the valley edges and control the location of the Snoqualmie River along some portions of the valley. Emergency Management Earthquake - Island County, Washington Image from the, Aquatic Lands Habitat Restoration Program, South Lake Washington Restoration Project, Scientific and Technical Support to Aquatic Programs, Washington Geologic Survey Publications Catalog, Washington Geologic Survey Photograph Collection, Wetlands of High Conservation Value Map Viewer, Timber Sale Remaining Volume by Purchaser Reports, Spanish - Brocha, Salal y Otros Productos Forestales, Complete: Baker to Bellingham Non-Motorized Recreation Plan, Community Wildfire Resilience and Preparedness, Utility Wildland Fire Prevention Advisory Committee, Blanchard, Reiter, Walker Valley and Nearby Islands, Teanaway Community Forest Advisory Committee, Teanaway Community Forest Advisory Committee Past Meetings, Faults and Earthquakes in Washington State, Pacific Northwest Seismic Network Seismo Blog, https://buildingfailures.files.wordpress.com/2014/02/tiltedbuilding.jpg, Pacific Geoscience Center of the Natural Resources of Canada. The Eastern Sierra fault along the east side of the Sierra Nevada mountains in California is a good example of an active normal fault. It might as well have been sitting in a drawer, Johnson said. . Theres a must-see documentary film called Cascadia The Big One that exposes whats currently going on in this region of the Cascade volcanoes and the Pacific NorthWest. Hold on to any sturdy shelter until the shaking stops. This map shows areas of seismic risk from high (red) to low (grayish-green). He said scientists have known about the southern Whidbey fault for decades. Although we know much about active faults and earthquakes, there is much more to learn. The Pacific Tsunami Warning Center is located in Hawaii and is responsible for issuing alerts to all the countries that border the Pacific Ocean. In addition, the Survey performs seismic safety evaluations of schools. Dishes jitter off tables, shattering on the floor. In fact, new faults are found every year during our geologic mapping efforts. If folding on the Little Bear Creek lineament resulted in one or two of unconformities, the poorly constrained timing of the earthquakes is younger than 12,000 yr BP and older than about 2,850 cal yr BP. They didnt grow up here, they havent heard this story. In general, larger faults make larger earthquakes. ?7) and represents a potential seismic hazard to residents of the Puget Lowland. The southern Whidbey Island fault should be considered capable of generating large earthquakes (Ms ?? Black lines are trace projections of the South Whidbey Island Fault, Seattle Fault Zone, and Tacoma Fault Zone faults and the N-S Hood Canal and Puget Sound faults of S. Y. Johnson et al. Earthquake Fault Maps in Seattle and Washington State But Forson says you also need to know what to do when the shaking happens. Kristin D. Morell 1 *, Christine Regalla 2, Lucinda J. Leonard 3, Colin Amos 4, Vic Levson 5. Earthquakes can trigger landslides and tsunamis which can happen after the main event. Map Releases; Topographic (Topo) Maps; Volcanic Maps; All Maps; Multimedia Gallery. An official website of the United States government. Under a scenario played out in a 2019 U.S. Department of Homeland Security study, state-maintained bridges would be severely damaged, leaving them unusable for months or years. Tohoku killed nearly 16,000 people; most died as a result of drowning or being crushed in the tsunami. And while scientists keep digging for more information and more situational awareness of what we face, the other problem is human. Across the northern portion of Bainbridge Island, light radar or lidar images taken from airplanes clearly show the Seattle Fault running right on the surface. They conclude the observed features have a glaciotectonic origin and are not seimotectonic. Electricity, water, natural gas, and phones may not work. At the Brightwater treatment plant in Woodinville and at Crystal Lake in Maltby, the government researchers found telltale slopes of offset ground, known as scarps, indicative of a long-ago quake. Surface Geology | WA - DNR Faults can also occur within a tectonic plate when the plate itself is deforming. Each peak of the Olympics stuck out with picturesque clarity in the distance. Earthquakes between 45 and 185 miles deep are called intermediate, and earthquakes over 185 miles deep are called deep. The spectacular falls flow over the remains of a newly discovered 20-million-year-old volcano, apparently formed atop the main part of the fault zone as magma rose upward along weak fault planes. After the shaking stopped the sand regained its strength. HAZARD MAPS As part of the Hazard Mitigation Planning process, mapping of the hazards that have the potential to affect the jurisdiction is performed using geographic information systems (GIS) software. If a large earthquake happens, be prepared for many more earthquakes. Quake fault under Whidbey linked to potential mainland dangers This movement happens because stress builds up as tectonic plates move. Hover over a cluster of earthquakes to learn about the different types in the Pacific Northwest. Many faults have not been studied enough to know if they are active. A normal fault occurs when two blocks are pulled away from each other. These differences are related to the overall pattern of stress in the crust, what types of rocks the crust is made from, and how many faults there are. Jump from 60 to 600 per week in just 5 years in Pahala, Is the Cascadia Subduction Zone about to blow? Many low-lying areas have wet soil or sediment beneath them that could liquefy during earthquakes. If they know theres data available that could help them in any way, they want to get it. By sampling sediment from the marsh to the beach berm, Sherrod and his research partner, Harvey Kelsey, developed a timeline of the oceans climb. But it didnt. They knew something was there, said Sam Johnson, a retired USGS geologist who would follow up on their work. The term active can have different meanings. Do you know what to do if there is an earthquake? Finding nothing of serious monetary value, the companies abandoned reams of information they had gathered through seismic surveys. The Westport area is now the first in North America to have acommunity vertical evacuation structure, a building strong enough to resist earthquake and tsunami wave forces and give people a platform above the expected wave heights. They didnt recognize the significance of what they found. Like other faults, when enough stress builds up, the megathrust will rupture. <> We just dont know when.. Another big one is expected, and it could be devastating. The Survey works to increase public and scientific understanding of fault and earthquake hazards in our state. The largest active fault that will affect Washington (and the whole Pacific Northwest) is the Cascadia subduction zone. Washington, Seattle, WA 98195 2 U.S. Geological Survey, 345 Middlefield Road, M/S . The marshy deposits are about a meter higher at Lake Hancock. With Medical Martial Law imposed in Washington state. Areas like these are also susceptible to liquefaction. However, we can learn which faults are active and which are inactive. Liquefaction is when wet soil or sediment loses strength because it is being shaken during an earthquake. Washington has dozens of active faults and fault zones. Other types of seismic energy (S waves) also travel through the earth, but they move with a side-to-side (shearing) motion. The map is from a 2007 report (click here to download) on seismic design categories in Washington. In some areas getting up a hill to higher ground will be difficult. These aftershocks can last for hours to weeks or months. Ready to retrofit? Throughout the world shallow earthquakes generally refer to earthquakes that are less than ~45 miles deep. This northwest-trending fault comprises a broad (as wide as 6-11 km), steep, northeast-dipping zone that includes several splays with inferred strike-slip, reverse, and thrust displacement. The Cascadia Subduction Zone (also known as the CSZ) is a 700-mile long fault zone located off the western coastline of British Columbia, Washington, Oregon and northern California. Lidar maps show the Earths surface without vegetation. For the most up-to-date information, please refer to the interactive fault map. Emergency Management Hazard Maps - Island County, Washington When an earthquake happens there will not be time to google what you are supposed to do. Know what other hazards you might face. Also, very large earthquakes were difficult to measure accurately. Mudslides. PI22343). Watch the video below to learn how you can be ready for the next earthquake. Johnson et al. Below you will find links to view and download hazard maps created for each jurisdiction included in the current mitigation planning process. South Whidbey Island Fault Earthquake Scenario: 7.4 Magnitude Buildings Damaged: 320,776 Fatalities: 90 - 432 Injuries: 2,920 - 7,361 Economic Loss: $15,590,000,000 SeaTac Fault Earthquake Scenario: 7.2 Magnitude Buildings Damaged: 375,954 Fatalities: 16 - 123 Injuries: 1,394 - 3,404 Economic Loss: $13,400,000,000 Tacoma Fault Finding Concealed Active Faults: Extending the Southern Whidbey Island and the Red Cross will be there to care for them. Southeast Extension of the Southern Whidbey Island Fault By Human Capital March 19, 2019. sw_whidbeyfault_rev122706.pdf (28.68 KB) Even when an earthquake happens on a fault that doesnt reach the surface, the ground can still show signs of cracking. These cookies do not store any personal information. These include the: Southern Whidbey Island Fault (SWIF) Seattle Fault Devils Mountain Fault Strawberry Point fault Utsalady Point fault Westport currently is the only location with a vertical evacuation structure designed for a tsunami. Devils Mountain Fault -- Online Professional Paper - USGS The northwestern part of the fault zone forms the northeastern limit of the Port Townsend basin (Brocher and others, 2001 #4718). southern Whidbey Island fault zone (Class A) No. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. Faulting produced warping at the site of greater than 2 m. Radiocarbon ages provide a maximum age for the folding event of 12,09011,670 cal yr BP. (1996) used seismic-reflection profiles in Puget Sound near Whidbey Island, sea-cliff exposures on Whidbey Island, and sparse borehole data to map and interpret the SWIF as a broad fault zone (6 to 11 km wide) dipping steeply to the northeast. You will not be able to google what to do in an earthquake when it is happening. We pray for people of WA and our all north Americans as well. This website uses cookies to improve your experience while you navigate through the website. A lock () or https:// means youve safely connected to the .gov website. We work closely with the Washington Emergency Management Division, the Washington Seismic Safety Committee, and the Federal Emergency Management Agency to ensure that the best-available science is used in the development of hazard mitigation plans. 552 - Hood Canal fault zone (Class B) 570 - Seattle fault zone 572 - Southern Whidbey Island fault zone 575 - Saddle Mountain faults 581 - Tacoma fault zone. This category only includes cookies that ensures basic functionalities and security features of the website. A .gov website belongs to an official government organization in the United States. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. Because Japan was so well prepared, mostretrofitted buildingsoutside of the tsunami zone survived. And when are documentary film called Cascadia The Big One, Dangerous Inland Earthquake Destroys Homes and Schools near Jakarta, Indonesia, Terrifying video shows olive grove turned into a Gigantic Canyon after Turkeys earthquake split land in huge rifts. This is called liquefaction and is discussed in the next section. The shaking usually lasts less than a minute and doesnt generally cause a tsunami or have many aftershocks. Some residents may lose housing temporarily or permanently. Stories from tribes near Seattle have also helped us to learn that the last earthquake on the Seattle fault was about AD 900950. Often this cracking happens because a soft part of the ground liquefies during the shaking. M 7.4 Scenario Earthquake - Southern Whidbey Island fault-southern Overview Interactive Map Regional Information Impact ShakeMap Technical Origin Download Event KML Earthquakes Hazards Data & Products Learn Monitoring Research M 7.4 Scenario Earthquake - Southern Whidbey Island fault-southern 2017-05-12 20:14:09 (UTC) 48.036N 122.452W This was a problem because no two locations would agree on the size of the same earthquake. Each type has different kinds of earthquakes. Most faults in Washington are a mix of a strike-slip fault and a thrust or reverse fault. . The study of seismic waves is called seismology and has allowed scientists to learn much about the internal structure of the Earth. For more information about earthquakes, faults, and emergency preparation, consider visiting the following sites: This map shows areas of seismic risk from high (red) to low (grayish-green). Finding faults and knowing how often they rupture is one of the most important tasks to keep society safe from these hazards. Depending on the type of fault, the ground can move laterally, vertically, or a combination of both. It will happen; we dont know when.. The key, Sherrods group would discover, was buried on Whidbey Island under layers of mud, peat moss and decaying marsh grass in the murky tidal waters at Crockett Lake, alongside the Coupeville ferry dock. Oblique convergence and clockwise rotation along the continental margin are the inferred driving forces for ongoing deformation. People are already fighting over toilet paper, just imagine what will it be like when they go shopping for food and the shelves are almost empty. Still think well avoid Gods wrath, its not going to happen regardless of what the multi millionaire TV preachers tell you. Tsunamis and seiches can also be triggered by large slides, both on land and underwater. For several years, scientists pondered where this important regional fault zone continues southwestward from its mapped location in the Everett area. Experts have warned that UK outbreak may be around two weeks behind Italys. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. stream For each increase in earthquake magnitude, there are about 10 times fewer earthquakes. The moment magnitude scale is a type of logarithmic scale, where each increase of 1 means ~32 times more energy is released. Because after a region-wide event, it could take that long for help to come from the rest of the country and world. The Flying Squirrel and Mountain Beaver trenches cross the Cottage Lake lineament. Quaternary Fault and Fold Database of the United States - USGS The southern Whidbey Island fault zone (SWIF), as previously mapped using borehole data, potential field anomalies, and marine seismic reflection surveys, consists of three subparallel, northwest trending strands extending ~100 km from near Vancouver Island to the northern Puget Lowland. As of January 12, 2017, the USGS maintains a limited number of metadata fields that characterize the Quaternary faults and folds of the United States. Finding and mapping these faults is an important mission of the Washington Geological Survey. " A lot of people are transplants, " Forson said. A few miles southeast across the white-capped waves of Admiralty Bay, Lake Hancock rises and falls with the tides. 572 Last Review Date: 2016-11-29 On a brilliant November day, Sherrod took in the panorama from the parks bluff. Sometimes Geologists can use the offset land surface to understand how much the fault moved during the earthquake. At the Washington Geological Survey, active means that a fault has evidence for movement within the Holocene time period (since about 12,000 years ago). Close to shore, this same wave could reach heights of 30100 feet or more. ShakeMapGeologicSummaries - University of Washington The Seattle Fault is a zone of multiple shallow east-west thrust faults that cross the Puget Sound Lowland and through Seattle (in the U.S. state of Washington) in the vicinity of Interstate Highway 90.The Seattle Fault was first recognized as a significant seismic hazard in 1992, when a set of reports showed that about 1,100 years ago it was the scene of a major earthquake of about . It devastated the coast of the Pacific Northwest and sent an orphan tsunami to Japan. This is a hypothetical scenario created by Mark Murphy of the Snohomish County Department of Emergency Management. This can cause landslides to occur where they wouldnt normally happen. Earthquakes on faults like these may cause tsunamis in the Puget Sound region. The southeastern and central parts of the southern Whidbey Island fault zone form the southwest margin of the Everett basin and northeast boundary of the Seattle basin. Hundreds could die, with thousands more injured. Others, like the Seattle fault and southern Whidbey Island fault zone, cross under major cities and pose a significant hazard. Bookcases and china cabinets topple, trapping people beneath. This uplift creates a very broad wave called a tsunami. Map of Puget Sound and Hood Canal in north-central - ResearchGate The San Andreas fault in California is a good example of a very active strike-slip fault. Around Puget Sound, it seems everyone knows about The Big One, the potential magnitude 9.0 Cascadia Subduction Zone megaquake some scientists say is due any day. This northwest-trending fault zone extends more than 65 km across Possession Sound, southern Whidbey Island, Admiralty Inlet into the eastern Strait of Juan de Fuca. The experts say few are ready. Puget Sound Earthquake Faults - Seattle Earthquake Faults Most damage and loss of life in earthquakes is a result of ground shaking. The southern Whidbey Island fault (SWIF) stretches from the vicinity of Victoria, B.C., across Puget Sound as far as the Cascade Range. Deep faults can occur where two tectonic plates collide and one of the plates is forced beneath the other. Though it was not directly related to Johnsons work, he asked a friend working for Mobil Oil to pass along the information. Each year we map additional areas and learn more about existing faults and (or) discover new ones. Along the coast residents may have between 20 and 30 minutes to get to higher ground. Here, were looking at one of the bigger faults in the region, he said. The southern Whidbey Island fault divides the two. 1 NE 7th Street Coupeville, WA 98239, Main Line: The southern Whidbey Island fault zone (SWIF) is a mostly concealed, northwest-trending structure extending across southern Whidbey Island toward Vancouver Island (Figures 1 and 2). Bubbles of methane rising from seafloor in Puget Sound His team wanted to find the rate of sea level rise along the shore. The Moment Magnitude Scale (M) measures the total amount of seismic energy (known as moment to engineers and seismologists) released by an earthquake. But quiet period wont last, Strongest earthquake in 40 years rattle residents of Buffalo, NY, Is Istanbul next? If the epicenter is Everett, the SWIF could cause. Later movement on this long-term active fault zone cut the volcano. By clicking Accept, you consent to the use of ALL the cookies. And being ready means being able to support yourself, your loved ones, your neighborhood for 2 weeks. Beef Barley and French Onion trenches cross the Little Bear Creek lineament. The April 1949 Tacoma earthquake measured 7.1 on the Richter Scale and caused damage from southern Oregon to British Columbia. District Court: (800) 946-9765, South Whidbey Island Fault (SWIF) M7.4 Earthquake Scenario. Since the last ice age, the southern Whidbey Island fault zone has probably spawned several highly destructive shallow earthquakes. USA Earthquake Hazard Map. An abrupt rise or decline in sea level would reveal if the fault had triggered a quake before. Quaternary Rupture of a Crustal Fault beneath Victoria, British In 2017, he began studying the possible aftermath of a major SWIF quake. The 2011 Tohoku earthquake in Japan occurred on this type of fault and released enough energy to slightly change the Earths axis of rotation. Southern Whidbey Island Fault Zone Mapped through Snoqualmie Valley This video from the 2011 Tohoku subduction zone earthquake shows the earthquakes before, during, and after the main M8.7 event on March 11 (at 1:50 in the video). The next earthquake is inevitable, but the variability makes it difficult to know exactly when. Over time, fault movement has created some interesting geologic features. Once we got it, we were sort of shocked to see these big faults in the Puget lowlands, he said. Moving inland, the Seattle Fault is capable of a magnitude 7. This means that a tsunami made by an earthquake on the Cascadia subduction zone will start to impact the Washington coast in less than 15 minutes. An official website of the United States government. Most faults are considered active if they have evidence for movement (this includes earthquakes) within the past 12,000 years (the Holocene time period). Share sensitive information only on official, secure websites. Drop to your hands and knees. This map is from a 2007 report on the seismic design categories in Washington. This kind of landslide is called an earthquake-triggered landslides. Sherrod remembers his son, age 5 at the time, playing with toy trucks on the mossy banks of the marsh while the scientists worked. One of these cracks appeared along the pathway around Green Lake. The average time between large earthquakes is about 535 years, but has been as little as 200 years, and more than 1,000 years. It is a qualitative scale that ranges from IXI (1-11) and measures the amount of damage caused by an event. Hey Biden! Devastating wind storms. 12201 Sunrise Valley Drive Reston, VA 20192, Region 2: South Atlantic-Gulf (Includes Puerto Rico and the U.S. Virgin Islands), Region 12: Pacific Islands (American Samoa, Hawaii, Guam, Commonwealth of the Northern Mariana Islands), The southern Whidbey Island fault: An active structure in the Puget Lowland, Washington, S. Y. Johnson, C. J. Potter, J.M. In the area of North Bend, the fault zone is 4 miles wide and consists of a series of parallel faults. Charles Richter and Beno Gutenberg discovered that for every magnitude of earthquake, there are about ten times more earthquakes of the next lower magnitude. When a fault with vertical movement ruptures the ocean floor, it lifts up part of the ocean. Floods. Seattle Fault and Whidbey Faults HAZARD MAPS As part of the Hazard Mitigation Planning process, mapping of the hazards that have the potential to affect the jurisdiction is performed using geographic information systems (GIS) software. A strike-slip fault occurs when two blocks move past each other. The trenches exposed glacial deposits disrupted by faults and liquefaction features. Click the "Seismogenic Features" button in the Map Contents window to display faults and earthquakes. Expect and help to extinguish fires. Tap/click on "gear icon" for options and settings. We also use third-party cookies that help us analyze and understand how you use this website. Reverse faults are usually steep and occur in regions of compression. from Whidbey Island to Vancouver Island (Figure 1). Although both seiches and tsunamis can be large and destructive, they are created differently. For example, a building on soft soil will experience more shaking than the same building on bedrock. Theres a reason the lands around the Pacific Ocean are called the Ring of Fire. The earthquakes, tsunamis, and the proximity of volcanos are all part of the same system. Experts believe a magnitude 9.0 could happen there anytime in the next 200 years or so.