southern whidbey island fault map southern whidbey island fault map

Faults can also occur within a tectonic plate when the plate itself is deforming. Once a fault is located, it is important to know if it is active. Finding and learning about faults requires many different aspects of geology and geophysics. Large earthquakes are likely to happen in Washington during your lifetime. Earthquakes can be measured in many ways, but the most accepted method is called moment magnitude. The tsunamis can travel far inland and deposit layers of sand and organic material. The coast is now the home of one of the states largest network of warning sirens called All Hazard Alert Broadcast (AHABs). 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). <>/XObject<>/ExtGState<>/Pattern<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> Bookcases and china cabinets topple, trapping people beneath. stream The 1964 M9.2 Alaska earthquake created a large tsunami from the fault rupture, and many smaller tsunamis from on-land and underwater landslides. In some areas getting up a hill to higher ground will be difficult. For example, the Cascadia subduction zone has had between 15 to 19 earthquakes over the past 10,000 years. It will happen; we dont know when.. Another big one is expected, and it could be devastating. These cookies will be stored in your browser only with your consent. The southern Whidbey Island fault represents a segment of a boundary between two major crustal blocks. An official website of the United States government. Scientists at the Washington Geological Survey, the U.S. Geological Survey, universities, and many private geologic consulting firms work diligently to understand how often earthquakes happen on various faults throughout Washington. Its a natural curiosity.. The shaking can also cause landslides, surface ruptures, ground cracks, liquefaction, tsunamis, and seiches (standing waves). (360) 678-5111 In this sense, the shaking of the ground is the sound of rocks breaking and moving deep within the Earth. Proceed cautiously once the earthquake has stopped. Photo from, Liquefaction can be a big problem. Dishes jitter off tables, shattering on the floor. Sherrod and others, 2008 #7652) report results from four trenches located near Crystal Lake: Flying Squirrel trench (572-5), Mountain Beaver trench (572-6), Beef Barley trench (572-7), and French Onion trench (572-8). Bubbles of methane rising from seafloor in Puget Sound . Each type has different kinds of earthquakes. A baristas hand hovers over the bean grinder. Click the "Seismogenic Features" button in the Map Contents window to display faults and earthquakes. Be prepared and read more on DNR, USGS, King5, Strange Sounds and Steve Quayle. The moment magnitude scale replaced the Richter scale in the late 1970s. 1 NE 7th Street Finding nothing of serious monetary value, the companies abandoned reams of information they had gathered through seismic surveys. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. A thrust fault is a special kind of reverse fault that has a shallow dip. Another piece can be seen under the elevated lanes of northbound Interstate 5 in South Seattle not far from the Rainier brewery. The French Onion trench exposed glaciolacustrine claystones, till, colluvial deposits, and Holocene soils. And experts fear it could be even worse than The Big One.. Strait of Juan de Fuca Fault Map The Puget Sound faults under the highly populated Seattle and Puget Sound region of Washington state form a regional network of interrelated seismologic geologic faults. Faults are features in the Earths crust where rock periodically breaks and moves, releasing seismic energy and creating an earthquake. A lot of people are transplants, Forson said. The San Andreas fault in California is a good example of a very active strike-slip fault. The risk is complicated, but there are millions of people who live in the Seattle area, said Forson. Oil companies descended in search of riches. DO NOT get in a doorway. A 2014 map shows what we know about the age of faults in Washington. Theres approximately a 14% chance of another approximately M9 earthquake occurring in the next 50 years. This can cause landslides to occur where they wouldnt normally happen. Each of the earthquakes listed on the bottom of the screen is capable of significant damage. Surface Geology | WA - DNR Contact Us, Whidbey Office America is going to be punished just like the rest of the world. Make an emergency response plan for you and your family. Deformed recessional outwash deposits and Holocene deposits were exposed; three unconformities separated the units. Seattle Fault Lines. Map by And while scientists keep digging for more information and more situational awareness of what we face, the other problem is human. PDF The Cottage Lake Aeromagnetic Lineament: a Possible Onshore Extension HomePrograms and ServicesGeologyGeologic Hazards. Transpressional deformation along the southern Whidbey Island fault is indicated by alongstrike variations in structural style and geometry, positive flower structure, local unconformities, out-of-plane displacements, and juxtaposition of correlative sedimentary units with different histories. The Seattle Fault is also likely to create a tsunami that would inundate Harbor Island and much of SODO, Interbay, and the waterfront. Most injuries occur when people inside change rooms or try to leave the building. Expect aftershocks. The western half of Washington state is considered earthquake country, with the potential for very large quakes. A small quake was registered in the Coupeville area just this summer. Get On The List To Receive Your Daily Dose Of Weird News And Amazing Phenomena. Earthquakes occur nearly every day in Washington. Not all faults are active. In Washington, we do not have tsunami walls. Johnson and others (1996 #4751) described multiple sub-parallel strands and referred to the overall structure as the "southern Whidbey Island fault zone," and this name is also used herein for this zone of faults that crosses the southern part of Whidbey Island. Throughout the world shallow earthquakes generally refer to earthquakes that are less than ~45 miles deep. A .gov website belongs to an official government organization in the United States. So the fault remained mostly a mystery until the 1990s. Even when the location of a fault is known, there is much additional work to determine how hazardous it may be. Black squares are urban sewer outfalls, which don't match the bubble plumes' locations. In the early 2000s, USGS scientists including Brian Sherrod set out to further Johnsons work and better understand the slumbering fissure. Consider a magnitude 7.4 quake with Whidbey Island at or near the epicenter. EVERETT The South Whidbey Island Fault is connected to a system of powerful earthquake fault lines stretching from Victoria, B.C., to Yakima that is capable of unleashing a devastating. Save my name, email, and website in this browser for the next time I comment. The crustal faults the Seattle Fault, the South Whidbey Island Fault, the Tacoma Fault those are less well known, said Forson. Kelsey and others (2004 #7651) compared sea-level histories at two salt marshes that straddle a northeast strand of the southern Whidbey Island fault zone: Crockett Marsh (site 572-1) located north of the northeastern fault strand is 8 km north of Hancock Marsh (site 572-2), south of the fault strand. Stories from tribes near Seattle have also helped us to learn that the last earthquake on the Seattle fault was about AD 900950. The Survey has developed several types of hazard maps for different types of earthquake- and fault-related hazards: The maps are used by state and local governments to develop and update hazard-mitigation and response plans, and to mark geologically hazardous areas. 4 0 obj This scenario was modeled on the part of the SWIF from Woodinville to just west of Whidbey Island. The Cascadia subduction zone off the Washington and Oregon coast is capable of some of the largest earthquakes in the world. The Straight Creek fault in the Cascade Range is an example of this kind of fault and has ~5060 miles of movement across it. Stratigraphy in the Flying Squirrel trench showed gentle warping of late glacial and post-glacial sediments; no faults were exposed. We just dont know when.. You also have the option to opt-out of these cookies. Johnson and others (1996) have described the southern Whidbey Island fault ( figure 1) as a broad (6 - 11 km) transpressional zone comprising three main splays, within which the local late Quaternary uplift rate is at least 0.6 mm/yr. Others, like the Seattle fault and southern Whidbey Island fault zone, cross under major cities and pose a significant hazard. These faults and earthquakes occur in oceanic crust as it is subducted beneath the continent. Years ago, Howard Gower and James Yount came to the Puget lowlands to study earthquake risks and stumbled on what appeared to be a fault in Island and Snohomish counties. Earthquakes. 2 0 obj Stratigraphy and diatom assemblages of the marsh cores suggest Crockett Marsh underwent a 12 m of abrupt uplift relative to sea level at a time that relative sea level remained the same at Hancock Marsh. His team wanted to find the rate of sea level rise along the shore. Aftershocks can be nearly as large as the main earthquake and can cause significant additional damage. Earthquakes can trigger landslides and tsunamis which can happen after the main event. In 2017, he began studying the possible aftermath of a major SWIF quake. If you are in bed: STAY there and COVER your head and neck with a pillow. 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. Over time, fault movement has created some interesting geologic features. The fault zone, known to geologists as SWIF, cuts through Puget Sound in a diagonal line roughly from Port Townsend to the southern tip of Whidbey Island, then to Mukilteo, Bothell, North Bend and possibly farther east below the Cascades. But scientists theorize that the area has suffered only four . @\;L;=}%FC*l $@ 4x: 888O~xrsxx'/*rGRF\gI%~x(G-^-hjjq kx/V ou0hyegy0;ei`Tx&ilZ )TmZ$vb,`bQm|DR5x/ Faults often occur at and near the boundary of large tectonic plates because the plates are moving in different directions. The medic said colleagues were becoming sick and emotionally overwhelmed Each year we map additional areas and learn more about existing faults and (or) discover new ones. Large and damaging earthquakes are inevitable in Washington, but no one knows exactly when they will happen. In the area of North Bend, the fault zone is 4 miles wide and consists of a series of parallel faults. If the epicenter is Everett, the SWIF could cause. At a downtown coffee shop, the mugs begin to chatter. Earthquakes, tornadoes, hurricanes, pandemics, too many people think it cant happen to them and they still think that they can still make a quick run to Walmart to pick up enough to last for 2-3 days and then the govt. Photo by G.K. Gilbert, from the Steinbrugge Collection of the UC Berkeley Earthquake Engineering Research Center. This kind of grouping gives us information about how common earthquakes might be and how large an area may be affected. Washington has dozens of active faults and fault zones. Some people in places like SODO and Harbor Island may have to flee to higher floors in a building. Tsunami waves can travel over 500 miles per hour in the open ocean. Every year Western. A lock () or https:// means youve safely connected to the .gov website. Early mapping of the three subparallel, northwest trending strands of the southern Whidbey Island fault zone was constrained by borehole data, potential field anomalies, marine seismic reflection surveys. He combed through state and federal data to understand the risks, and to help train first responders. Expect and help to extinguish fires. The Seattle fault is a good example of a fault that is mostly reverse. For example, if there is one M7 earthquakes in an area every 1,000 years, then there will be about 10 M6 earthquakes, 100 M5 earthquakes, and 1,000 M4 earthquakes during the same 1,000 years. Theres an uneasy hush. 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 . The SWIF was first recognized and mapped at a regional scale by Gower and others (1985) on the basis of gravity and aeromagnetic anomaly maps. The 1949 earthquake near Tacoma triggered a landslide near the Tacoma Narrows that caused a local tsunami. Seismologists estimate that such quakes and tsunami waves occur roughly every 500 years on average on the Cascadia Subduction Zone. Earthquake Fault Maps in Seattle and Washington State Hover over a cluster of earthquakes to learn about the different types in the Pacific Northwest. By Julia-Grace Sanders The Everett Herald May 14, 2021 2:40 pm, Luella Meaux: November 21, 1929 January 21, 2023, Claudia Anderson: October 1, 1939 January 31, 2023, Chieko Yamane Miller: July 26, 1936 February 16, 2023, Guarding the flock: Chicken farms rely on specialized dogs, Flying colors: Irish artist finds success on Whidbey. The strength of ground shaking (called strong motion by seismologists) usually decreases with distance from the earthquake source. Were working on pedestrian evacuation maps that show the best routes for pedestrians to take to evacuate, said Forson. A reverse fault occurs when two blocks are pushed together and one moves up and over the other. This might include flammable appliances like a water heater, tall items like book cases, or heavy pictures. Unlike sound, ground shaking can be amplified or attenuated (made less) depending on the type of material at the Earths surface. A damaging earthquake is inevitable on this fault, but we do not know exactly when it will happen. Tsunamis and seiches can also be triggered by large slides, both on land and underwater. Scientists have also dated large underwater landslides and turbidites that travel from the continental edge far out into the ocean basin. The southern Whidbey Island fault represents a segment of a boundary between two major crustal blocks. ; (5) large-scale liquefaction features in upper Quaternary sediments within the fault zone; and (6) minor historical seismicity. A half dozen people reaching for the last can of soup, someone could lose their life over that. They didnt grow up here, they havent heard this story. , * NOTE: Hazard maps for each jurisdiction will only be included if that jurisdiction is at risk to that hazard., Copyright Island County. Hundreds could die, with thousands more injured. If they know theres data available that could help them in any way, they want to get it. Devastating wind storms. Its certainly not to scare you. The southern Whidbey Island fault divides the two. There are many other active faults in Washington and any of these could produce a large earthquake in the future. 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. 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. Necessary cookies are absolutely essential for the website to function properly. The Port of Coupeville will apply for a grant to fund two electric vehicle charging stations. Maps. Earthquake Hazards - Maps | U.S. Geological Survey Johnson and others (1996 #4751) described the structure and stratigraphy of the southern Whidbey Island fault zone. Sheriff:(360) 679-7310, Juror Recordings The term active can have different meanings. This is sometimes called "The Big One" by news media. A seiche is a large standing wave caused by the resonance of a particular period of wave energy. endobj A magnitude 7.4 along the southern Whidbey fault would rattle 18 counties in Washington, according to a federal projection . The seismic mapping had cost millions of dollars far beyond what most geologists on a government budget could scrape together. In addition, the Survey performs seismic safety evaluations of schools. 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. This means that a large area feels the shaking, but the intensity is less than a similar shallow earthquake. Learn about at-risk areas and become prepared. #4747 Blakely, R.J., Wells, R.E., and Weaver, C.S., 1999, Puget Sound aeromagnetic maps and data: U.S. Geological Survey Open-File Report 99-514. Radiocarbon dating and other paleoseismic methods have also confirmed this date. Once the shaking has stopped, exit the building if it is safe to do so. It devastated the coast of the Pacific Northwest and sent an orphan tsunami to Japan. This evidence can come from finding something younger than 12,000 years that has been deformed or moved by the fault. Here, were looking at one of the bigger faults in the region, he said. The shaking usually lasts less than a minute and doesnt generally cause a tsunami or have many aftershocks. Latest earthquakes map and list (past 24 hours, M2.5+) from the ANSS (Advanced National Seismic System). For the most up-to-date information, please refer to the interactive fault map. 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. The Cascadia subduction zone just off the Washington coast is this kind of fault and is one of the largest geologic hazards to our state. In Seattle, the quake damaged buildings, weakened bridges, started fires and opened cracks in the earth. Customers lift their eyes from phone screens. Landslide at Salmon Beach was triggered by the 1949 Tacoma earthquake and caused a tsunami. The southern Whidbey Island fault, and several others, were exposed for the first time from a camouflage of forest, ocean and glacial sediment. 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. The Eastern Sierra fault along the east side of the Sierra Nevada mountains in California is a good example of an active normal fault. Part 2 will be full Martial Law and mandatory vaccines? This kind of landslide is called an earthquake-triggered landslides. The fault, not so much. Sherrod remembers his son, age 5 at the time, playing with toy trucks on the mossy banks of the marsh while the scientists worked. In general, larger faults make larger earthquakes. Know what to expect. from Whidbey Island to Vancouver Island (Figure 1). HOLOCENE FAULT SCARPS AND SHALLOW MAGNETIC ANOMALIES ALONG THE SOUTHERN WHIDBEY ISLAND FAULT ZONE NEAR WOODINVILLE, WASHINGTON By Brian L. Sherrod1, Richard J. Blakely2, Craig Weaver1, Harvey Kelsey3, Elizabeth Barnett1, and Ray Wells4 1 U.S. Geological Survey, Dept. Snohomish, King and Island counties would be expected to see the. A paleoseismologist will look for surface ruptures along faults and may use carbon-14 dating to learn when the rupture happened. A low-angle fault, which is not conclusively earthquake related, separates a diamicton from the overlying recessional outwash deposit. The affiliate sales will help us to continue the hard work we are putting in this website. 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). and the Red Cross will be there to care for them. Reverse faults are usually steep and occur in regions of compression. Most faults are considered active if they have evidence for movement (this includes earthquakes) within the past 12,000 years (the Holocene time period). Tsunamis are a common result of large earthquakes in Washington. Videos: Strong M6.0 earthquake rattles Mindanao in the Philippines, Dramatic earthquake increase in Hawaii! Kristin D. Morell 1 *, Christine Regalla 2, Lucinda J. Leonard 3, Colin Amos 4, Vic Levson 5. Puget Sound faults - Wikipedia This map shows different seismic design categories that correlate with amount of seismic risk. Tsunamis triggered by earthquakes usually require at least a M7 event. Even places that are far from active faults are still at risk during a large Cascadia subduction zone earthquake. That could spell trouble not only for its namesake island but for south and north King County and further west. A national credit rating service has improved its opinion of WhidbeyHealths financial future. Scientists are not sure how far east it goes. Large earthquakes are less common but can cause significant damage to the things we count on in everyday life, such as buildings, roads, bridges, dams, and utilities. Identify and secure items in your home or work that could cause damage. This part of the Japanese coast had not seen this type of seismic rupture in some 800 years, and what failed was that walls built to keep tsunami waves were not high enough. Floods. This diagram shows the many types of active faults and the general location of past earthquakes in Washington. The Cascadia subduction zone along the Washington and Oregon coast is one of the biggest hazards to our state and is a good examples of this kind of fault. Photo from https://buildingfailures.files.wordpress.com/2014/02/tiltedbuilding.jpg. Finding faults and knowing how often they rupture is one of the most important tasks to keep society safe from these hazards. Resources on tsunami danger and preparedness in Westport, Grays Harbor County, Long Beach Peninsula, and Coastal evacuation maps. The Survey conducts and publishes geologic mapping to identify and characterize faults throughout the state. These aftershocks can last for hours to weeks or months. On a brilliant November day, Sherrod took in the panorama from the parks bluff. This is a very good example of a strike-slip fault. Information from seismic-reflection profiles, outcrops, boreholes, and potential field surveys is used to interpret the structure and history of the southern Whidbey Island fault in the Puget Lowland of western Washington. 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 Photo by Steve Palmer. The Geologic Information Portal has a Natural Hazards theme that shows active faults and earthquakes. 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. Some parts of major cities (including Seattle, Tacoma, and Olympia) have been built on land that was reclaimed from soft and wet tidal ocean areas. 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.