Fault lines in the New Madrid seismic zone are being mapped, thanks in part to . In the angle between these is located the minor Lincoln Creek uplift, the Doty Hills, and, further west, an impressive chunk of Crescent basalt. [96] As the juxtaposition of various disparate tectonic structures in northwest Washington requires significant strike-slip movement, it is further expected that this contact will be a major fault.[97]. 112 earthquakes in the past 365 days. 14 earthquakes in the past 30 days. [5] The southern limit nearly matches the southern limit of the glaciation; possibly the seismicity reflects rebound of the upper crust after being stressed by the weight of the glacial ice. The energy released depends on the length of the fault; the faults here are believed capable of generating earthquakes as great as M 6 or 7. The Cascadia Fault is 620 miles long off the coast of Washington and British Columbia. Mount Vernon Fault/Granite Falls FZ/Woods Creek, Rogers Belt (Mount Vernon Fault/Granite Falls Fault Zone), Saint Helens Zone and Western Rainier Zone, Quaternary fault and fold database (QFFDB), USGS QFFDB Fault #574, Devils Mountain Fault, USGS QFFDB Fault #571, Strawberry Point Fault, USGS QFFDB Fault #573, Utsalady Point Fault, Brightwater regional sewage treatment plant, USGS QFFDB Fault #572, Southern Whidbey Island Fault, USGS QFFDB Fault #575, Saddle Mountain Faults, "A Rifted Margin Origin for the Crescent Basalts and Related Rocks in the Northern Coast Range Volcanic Province, Washington and British Columbia", "Preliminary atlas of active shallow tectonic deformation in the Puget Lowland, Washington", "Volcanism, Isostatic Residual Gravity, and Regional Tectonic Setting of the Cascade Volcanic Province", "Findings on the southern Whidbey Island fault zone from aeromagnetic anomalies, lidar surveys, and trenching", "The Saddle Mountain Fault Deformation Zone, Olympic Peninsula, Washington: Western Boundary of the Seattle Uplift", "Connecting Crustal Faults and Tectonics from Puget Sound across the Cascade Range to the Yakima Fold and Thrust Belt, Washington: Evidence from New High-Resolution Aeromagnetic Data [Abstract GP232-02]", Eos, Transactions, American Geophysical Union, "The Cottage Lake Aeromagnetic Lineament: A possible onshore extension of the Southern Whidbey Island Fault, Washington", "Location, structure, and seismicity of the Seattle fault zone, Washington: Evidence from aeromagnetic anomalies, geologic mapping, and seismic-reflection data", 10.1130/0016-7606(2002)114<0169:LSASOT>2.0.CO;2, "High-pressure metamporphism and uplift of the Olympic subduction complex", 10.1130/0091-7613(1990)018<1252:HPMAUO>2.3.CO;2, "Interpretation of the Seattle Uplift, Washington, as a Passive-Roof Duplex", "Tectonic elements and evolution of northwest Washington", "Quaternary faulting on Dow Mountain, Mason County", "Major Cenozoic faults in the northern Puget Lowland of Washington", "High-Resolution Seismic Reflection Imaging of Growth Folding and Shallow Faults beneath the Southern Puget Lowland, Washington State", "LITHOPROBE southern Vancouver Island: Cenozoic subduction complex imaged by deep seismic reflections", "Geologic map of the Lilliwaup 7.5-minute quadrangle, Mason County, Washington", "Geologic map of the Holly 7.5-minute quadrangle, Jefferson, Kitsap, and Mason Counties, Washington", "Geologic map of the Eldon 7.5-minute quadrangle, Jefferson, Kitsap, and Mason Counties, Washington", "Geophysical Investigation of the Southern Puget Sound Area, Washington", "Geologic Map and Interpreted Geologic History of the Bow and Alger 7.5-minute Quadrangles, Western Skagit County, Washington", "Geologic Map of Washington Northwest Quadrant", "Geologic map of the Oak Harbor, Crescent Harbor, and part of the Smith Island 7.5-minute quadrangles, Island County", "Geologic map of the McMurray 7.5-minute Quadrangle, Skagit and Snohomish Counties, Washington, with a Discussion of the Evidence for Holocene Activity on the DarringtonDevils Mountain Fault Zone", "Geologic map of the Fall City 7.5-minute quadrangle, King County, Washington", "Geologic map of the North Bend 7.5-minute quadrangle, King County, Washington, with a discussion of major faults, folds, and basins in the map area", "Geologic Map of the Snoqualmie 7.5-Minute Quadrangle, King County, Washington", "Geologic map of the Carnation 7.5-minute quadrangle, King County, Washington", "Supplement to the geologic map of the Carnation 7.5-minute quadrangle, King County, Washington Geochronologic, geochemical, point count, geophysical, earthquake, fault, and neotectonic data", "Geologic map of the Monroe 7.5-minute quadrangle, King County, Washington", "Geologic map of the Lake Joy 7.5-minute quadrangle, King County, Washington", "Geologic map of the Sultan 7.5-minute quadrangle, Snohomish and King Counties, Washington", "Geologic Map of the Lake Chaplain 7.5-minute Quadrangle, Snohomish County, Washington", "Geologic map of the Lake Roesiger 7.5-minute quadrangle, Snohomish County, Washington", "Geologic Map of the Granite Falls 7.5-minute Quadrangle, Snohomish County, Washington", "Imaging Crustal Structure in Southwestern Washington With Small Magnetometer Arrays", "Geology of the Mount St. Helens Area: Record of Discontinuous Volcanic and Plutonic Activity in the Cascade Arc of Southern Washington", "Geophysical constraints on Washington convergent margin structure", "Aeromagnetic map compilation: procedures for merging and an example from Washington", "Something old, something new, something borrowed, something blue - a new perspective on seismic hazards in Washington using aeromagnetic data", "Constraints on surface deformation in the Seattle, WA, urban corridor from satellite radar interferometry time-series analysis", "Crustal Structure and Earthquake Hazards of the Subduction Zone in Southwestern British Columbia and Western Washington", "Late Mesozoic or Early Tertiary Melanges in the Western Cascades of Washington", "Seismotectonic map of the Puget Sound region, Washington", "Distribution of late Cenozoic volcanic vents in the Cascade Range: Volcanic arc segmentation and regional tectonic considerations", "Geologic map of the Wildcat Lake 7.5' quadrangle, Kitsap and Mason Counties, Washington", "Fault scarp detection beneath dense vegetation cover: airborne LIDAR mapping of the Seattle Fault Zone, Bainbridge Island, Washington State", 10.1130/1052-5173(2003)13<0004:HLTOTP>2.0.CO;2, "Structural variation along the Devil's Mountain fault zone, northwestern Washington", 10.1130/0091-7613(1980)8<15:SOTCVC>2.0.CO;2, "Fault number 572, Southern Whidbey Island Fault", "Active shortening of the Cascadia forearc and implications for seismic hazards of the Puget Lowland", "Active tectonics of the Seattle fault and central Puget Sound, Washington Implications for earthquake hazards", 10.1130/0016-7606(1999)111<1042:ATOTSF>2.3.CO;2, "Evidence for Late Holocene Earthquakes on the Utsalady Point Fault, Northern Puget Lowland, Washington", 10.1130/0091-7613(1994)022<0071:OAEOTS>2.3.CO;2, "The southern Whidbey Island fault An active structure in the Puget Lowland, Washington", 10.1130/0016-7606(1996)108<0334:TSWIFA>2.3.CO;2, "Late Holocene displacement on the Southern Whidbey Island fault zone, northern Puget lowland", "The Tahuya Lineament: Southwestern Extension of the Seattle Fault? [51] But today, after 131 years of statehood, residents of this region still don't know if they have a legal right to walk across a privately . It's due for another one,. Ongoing mapping is revealing more faults. 0 magnitude subduction earthquake off the Washington coast would generate a tsunami capable of submerging not only coastal areas but also most of the Puget Sound shoreline . One study compared the relative elevation of two marshes on opposite sides of Whidbey Island, and determined that approximately 3,000 years ago an earthquake of M 6.57.0 caused 1 to 2 meters of uplift. Rainier is offset because the faults are deep and the conduits do not rise quite vertically.) Analysis of seismic profiles extending 50 km across the Puget Lowland from Lake Washington to Hood Canal indicates . [218] This would pose significantly greater seismic hazard than currently recognized, especially as the White River Fault is believed to connect with the Naches River Fault that extends along Highway 410 on the east side of the Cascades towards Yakima. They are also on-strike with a swarm of faults on the Columbia River, bracketing The Dalles. The SE striking Scammon Creek Fault seems to be terminated by the Salzer Creek Fault (the exact relationship is not clear), with the latter continuing east for another seven miles. A parallel line ("B") about 15 miles (25 kilometers) to the west corresponds to the western limit of a zone of seismicity stretching from the WRZ to southwest of Portland. PSLC--finding faults - University of Washington The Olympia structure also known as the Legislature fault[168] is an 80km long gravitational and aeromagnetic anomaly that separates the sedimentary deposits of the Tacoma Basin from the basalt of the Black Hills Uplift (between lines A and B on the map). (A) Map of the Seattle fault zone (SFZ) in the central Puget Sound Seattle Earthquakes, Types of Quakes & Fault Lines - TripSavvy [170] Gower, Yount & Crosson (1985), labelling it "structure L", mapped it from Shelton (near the Olympic foothills) southeast to Olympia (pretty nearly right under the state Legislature), directly under the town of Rainier, to a point due east of the Doty Fault, and apparently marking the northeastern limit of a band of southeast striking faults in the Centralia-Chehalis area. [112] But if the Seattle Fault should break in conjunction with other faults (discussed above), considerably more energy would be released, on the order of ~M 8. Somewhere between Puget Sound and Cascades foothills these two geological provinces come into contact. Puget Sound Lidar Consortium Finding faults scarp(n). Prior to 2000, prominent aeromagnetic anomalies strongly suggested that the fault zone continued southeast, perhaps as far as the town of Duvall, but this was uncertain as the SWIF is largely concealed, and the faint surface traces generally obliterated by urban development. New tsunami simulation predicts flooding on Olympic Peninsula | Tacoma (1997) a slab of rock mainly basalts of the Crescent Formation about 20km thick is being pushed up a "master ramp" of deeper material; this forms the Seattle Uplift. [42] Marine seismic reflection surveys show it striking northwest across the eastern end of the Strait of Juan de Fuca. Marine technician Sony Brugger, right, retrieves underwater sampling equipment during a December 2020 research cruise aboard the RV Rachel Carson. Analyze Instructions: Close. Other faults to the south and southeast the Frigid Creek Fault and (to the west) Canyon River Fault suggest an extended zone of faulting at least 45km long. The length of the Doty Fault is problematical: the report in 2000 gave it as 65km (40 miles), but without comment or citation. Active tectonics of the Seattle fault and central Puget sound A Massive Earthquake Is Coming to CascadiaAnd It Can't Be Stopped King County Emergency News. What makes the DotySalzer Fault (and the short Chehalis Fault striking due east from Chehalis) stand out from the many other faults south of Tacoma is its eastwest strike; the significance of this is not known. Glacially deposited and shaped fill covers most of the lower elevations of Puget Sound. The last large event was in 1700, but there is a 37 percent chance of an 7.1+ in the next 50 years. Some of these faults possibly developed in the Mesozoic, when these deposits were in the accretionary wedge;[72] the cross-cutting NE and NNE-striking faults that form the various basins resulted from a subsequent change to transtension. Western Washington lies over the Cascadia subduction zone, where the Juan de Fuca Plate is subducting towards the east (see diagram, right). Seismic tomography studies show a change in seismic velocities across the northern end of the SWIF, suggesting that this is also part of the Coast RangeCascade contact. King County Emergency Management. On the east, the Devils Mountain Fault connects with the south striking Darrington Fault (not shown) which runs to the OWL, and the Southern Whidbey Island Fault extends via the Rattlesnake Mountain Fault Zone (dashed line) to the OWL. Geologic Hazard Maps | WA - DNR A Tsunami Hits Puget Sound: New Simulation Shows How It Unfolds Black lines show the South Whidbey Island Fault Zone, the . Although the southwest striking Canyon River Fault is not seen to directly connect with the Saddle Mountain faults, they are in general alignment, and both occur in a similar context of Miocene faulting (where Crescent Formation strata has been uplifted by the Olympics) and a linear aeromagnetic anomaly. Estimated shaking in the Puget Sound - Strange Sounds [206] This line may also mark the northwestern boundary of the SWCC. 1958 and Geologic Map GM-34 for details.). [116] Subsequent authors were confident enough to trace the fault west of Bremerton to just north of Green Mountain (the northwestern corner of the Blue Hills uplift see "E" on the map a topographically prominent exposure of uplifted basalt) and just short of Hood Canal;[117] but reluctant to map the fault further west as the distinctive aeromagnetic lineament used to locate the Seattle Fault dies out just west of Bremerton. Simply put, the basement rock on the west side of Puget Sound does not match the basement rock on the east side. Turkey's fault line is similar to faults under Puget Sound Gonzalez: That Seattle Fault tsunami has been modeled by others. Whether the faulting continues eastward is not yet determined. Tobin says offshore faults tend to cause bigger earthquakes and are a larger tsunami risk. Geographic boundaries of Puget Sound and the Salish Sea Bubbles of methane rising from seafloor in Puget Sound The Seattle Fault is the most studied of the regional faults, which has led to several models of its structure, which may also be relevant to other faults. These are usually fairly short, and not believed to be significantly seismogenic. Shallow fault below Seattle went undiscovered for a millennium Page 2 of 4 / 2012-2013 Type of Earthquake Most earthquake hazards result from ground shaking caused by seismic waves that radiate out from a fault when it ruptures. It does bound the north side of the Chehalis basin, but the south boundary of the Black Hills Uplift is more properly the southeast striking Scammon Creek Fault that converges with the DotySalzer Creek Fault just north of Chehalis. Read More. It has been speculated that the OS might connect with the seismically active Saint Helens Zone (discussed below), which would imply that the OS is both locked and being stressed, raising the possibility of a major earthquake. Kinematic analysis suggests that if shortening (compression) in the Puget Lowland is directed to the northeast (i.e., parallel to Hood Canal and the Saddle Mountain deformation zone) and thus oblique to the Dewatto lineament, it should be subject to both strike-slip and dip-slip forces, implying a fault. This ramp could be either in the lower crustal blocks, or where the thrust sheet has split and one part is being forced over the next. 09 Feb 2023 03:01:00 In the map above these are represented by the pair of dotted lines at the lower right. Yet the SHZ and WRZ may be integral to the regional geology of Puget Sound, possibly revealing some deep and significant facets, and may also present significant seismic hazard. UW researchers model tsunami hazards on the Northwest coast Housing: The Puget Sound had the largest increase in population per One problem with this is that the parts of the SWIF east of Puget Sound do not show the velocity contrasts that would indicate contrasting rock types. However, most seismic activity is not associated with any known fault. Puget Sound faults - Wikipedia Puget Sound Tsunami Simulation - National Oceanic and Atmospheric [16] For the past 50 million years or so (since the early Eocene epoch) these have been thrust by subduction up against the North Cascades ("fixed block" in the diagram), which sit on the North American Plate. Toll Free 1-800-523-5044. About 1,100 years ago, a major earthquake rocked Puget Sound, suddenly shooting what is now Restoration Point on Bainbridge Island up about 23 feet while Seattle 's West Point sunk more than. If entirely analogous, then "roof duplex" might also apply, and the Olympia Fault would be a reverse fault similar to the Tacoma Fault. E.g., HH mlange rock has been found in Manastash Ridge, 110km to the south (look for the small sliver of purple near the bottom of the diagram). The Seattle Fault, a zone of east-west thrust faults under the Puget Sound and Seattle, last ruptured in a magnitude-7.0 to -7.5 earthquake about 1,100 years ago. (Their model of the Black Hills Uplift is analogous with their "wedge" model of the Seattle Uplift, discussed above, but in the opposite direction. But. [123] Other studies have faults extending NW or WNW from the SF towards Dabob Bay;[124] these are now recognized as part of the Dabob Bay fault zone. The geology also suggests that the DMF is moving obliquely up a ramp that rises to the east,[35] possibly an ancient coastal shore. [28] Faults and folds may develop where the thrust sheet is being bent, or where the leading edge is thrust over softer, weaker sedimentary deposits, and breaks off and slumps.
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