southern whidbey island fault map

% The Safe America Foundation suggests texting as a way of communication. The Survey is working with the Office of the Superintendent of Public Instruction (OSPI) and Reid Middleton, an engineering firm, to perform seismic safety assessments of 220 school buildings across the state. Devastating wind storms. Map by And while scientists keep digging for more information and more situational awareness of what we face, the other problem is human. Sherrods son has since completed graduate school in applied geosciences. <> One model suggests it extends to about 30 miles east of Yakima. An official website of the United States government. The most important thing you can do before the next earthquake is to prepare. If you are already planning your Christmas gifts, please buy with us on Amazon. This image shows the how the 1700 AD tsunami from the Pacific Northwest crossed the Pacific Ocean. Tohoku killed nearly 16,000 people; most died as a result of drowning or being crushed in the tsunami. All Rights Reserved 2021, Site Disclaimer The southern Whidbey Island fault: An active structure in the Puget Lowland Washington, Geological Society of America Bulletin 1996;108;334-354. In the 1990s, scientists producedan animationthat shows inundation, and people wont have much time to run to higher ground. 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. What about the localized tsunami risk? The team also found that accumulated movement on the fault has uplifted old Snoqualmie River sediments to their current position on ridges, in some places several hundreds of feet above the modern Snoqualmie valley floor. In the month after the main earthquake there were about 60 M7 and M6 earthquakes. This map of gravity residuals measured over the puget lowland reveals a pattern of deep, fault bounded basins (cool colors) and uplifts (warm colors). The years have gone by. . Because they rupture at such great depth, their seismic energy is distributed over a large area. The experts say few are ready. Other faults may lie entirely underground, or could be covered by vegetation and (or) sediment. Also, very large earthquakes were difficult to measure accurately. USA Earthquake Hazard Map. Photo by G.K. Gilbert, from the Steinbrugge Collection of the UC Berkeley Earthquake Engineering Research Center. Tsunamis and seiches are destructive waves which can be triggered by certain types of large earthquakes. Southeast Extension of the Southern Whidbey Island Fault By Human Capital March 19, 2019. sw_whidbeyfault_rev122706.pdf (28.68 KB) STAY THERE until the shaking stops. Although we know much about active faults and earthquakes, there is much more to learn. It will happen; we dont know when.. 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. Get On The List To Receive Your Daily Dose Of Weird News And Amazing Phenomena. Scientists are not sure how far east it goes. The threat to Puget Sound from a quake along the Cascadia Subduction Zone, off the coast of Washington, Oregon and California, is well documented. . Save my name, email, and website in this browser for the next time I comment. Radiocarbon ages of macrofossils constrain uplift timing to 2.83.2 ka. The Cascadia subduction zone off the Washington and Oregon coast is capable of some of the largest earthquakes in the world. People stagger into the streets to avoid an avalanche of debris. 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. The 2011 Tohoku earthquake in Japan occurred on this type of fault and released enough energy to slightly change the Earths axis of rotation. The Southern Whidbay Island Fault represents another major earthquake threat for Seattle and its residents. America is going to pay for sitting back doing nothing while almost 70 million babies were slaughtered and their body parts sold to the highest bidder for the last 43 years. Another big one is expected, and it could be devastating. Another piece can be seen under the elevated lanes of northbound Interstate 5 in South Seattle not far from the Rainier brewery. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. These include the: Southern Whidbey Island Fault (SWIF) Seattle Fault Devils Mountain Fault Strawberry Point fault Utsalady Point fault That may not sound like much more than the magnitude 6.8 quake of 2001 based on the numbers, but that the Nisqually quake occurred some 30 miles underground. endobj These cookies will be stored in your browser only with your consent. 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. 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. Because they need large earthquakes that move the ocean floor, tsunamis are most commonly made by subduction zone faults like those found off the coasts of the Pacific Northwest, Japan, and Chile. America is going to be punished just like the rest of the world. When an earthquake happens there will not be time to google what you are supposed to do. We just dont know when.. 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. 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. Johnson and others (1996 #4751) described the structure and stratigraphy of the southern Whidbey Island fault zone. SWIF ranges from 12 miles underground at its deepest to right at sea level in a few scattered spots, like Cama Beach, Holmes Harbor and Woodinville, according to Sherrods research. In this sense, the shaking of the ground is the sound of rocks breaking and moving deep within the Earth. The Richter scale was developed in southern California in 1935 and was based on the local ground motion. In effect, the wave energy is trapped by the edges of the body of water. What makes these faults mega is that the amount of energy released is hundreds to thousands of times more than almost any other type of fault. The San Andreas in California, for example, left gaping scars in the Earths crust, at the surface. Once the shaking has stopped, exit the building if it is safe to do so. For example, in the open ocean a tsunami may be less than a few feet tall. This new method allows geologists to see through trees and vegetation to find new faults. of Earth and Space Sciences, Box 351310, Univ. 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. 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 The age of the earthquake is learned by dating the organic material in these tsunami deposits. When a fault with vertical movement ruptures the ocean floor, it lifts up part of the ocean. Dishes jitter off tables, shattering on the floor. After the shaking stopped the sand regained its strength. After a large earthquake it is common to have other large earthquakes for hours, days, and even weeks. In 2017, he began studying the possible aftermath of a major SWIF quake. Do you live or work near an area that could have liquefaction? Hundreds could die, with thousands more injured. You also have the option to opt-out of these cookies. (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. An increase of 2 means that ~1,000 times more energy is released. And experts fear it could be even worse than The Big One.. If everyone tries to use their cell phones, it can overload the system. A thrust fault is a special kind of reverse fault that has a shallow dip. Consider a magnitude 7.4 quake with Whidbey Island at or near the epicenter. This is called liquefaction and is discussed in the next section. Strabge sounds very good report thanks a lot. The Mercalli Intensity scale is another historical way to measure the intensity of an earthquake. 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. Audio; Before and After Images; Images; Slideshows; Stereograms; Videos; Webcams; . 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. Here, were looking at one of the bigger faults in the region, he said. 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. It might as well have been sitting in a drawer, Johnson said. 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. Notable earthquakes in bold happened in Washington. Liquefaction has caused significant damage during earthquakes in Washington. These maps are created by small planes that use a specific type of laser to measure the elevation of the ground. However, seismic tomography studies (Brocher and others, 2001 #4718) reveal that only the northwestern end of the fault zone in the southeastern Strait of Juan de Fuca is associated with a strong velocity contrast. South Whidbey Island Fault (SWIF) M7.4 Earthquake Scenario Fire (Vegetation Condition Class) . Consider whether earthquake insurance is right for you. This evidence can come from finding something younger than 12,000 years that has been deformed or moved by the fault. 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). The crustal faults the Seattle Fault, the South Whidbey Island Fault, the Tacoma Fault those are less well known, said Forson. Faults can be grouped based on their relative movement into three types. A team headed by Joe Dragovich of DNRs Division of Geology and Earth Resources,assisted by geologists from King County, Pacific Northwest Seismic Network, Colorado College, and Washington State University, has been mapping in this area for the past three years. This earthquake caused parts of Restoration Point near on Bainbridge Island to be lifted 35 feet straight up. If the epicenter is Everett, the SWIF could cause. 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. Despite its location well offshore, a Cascadia quake would likely kill at least 10,000 and injure more than 30,000 in Washington, Murphy found. Some residents may lose housing temporarily or permanently. Kelsey and others (2004 #7651) suggest that the earthquake resulted in 2.5 m uplift of the salt marsh on the north side of the fault strand relative to the marsh on the south side; no fault scarp has been identified between the marshes. Johnson and others . Excavations across several LiDAR scarps show evidence for multiple post-glacial folding and faulting event on faults with reverse oblique sense of slip. Mapping along the Snoqualmie River valley also helped answer the important question of where the Seattle fault lies east of its last mapped position near Issaquah. Third, the South Whidbey Island Fault running from northwest to southeast of the southern tip of the island.