Earthquake scenario and probabilistic ground shaking maps for the Salt Lake City, Utah, metropolitan area

2002 ◽  
Keyword(s):  
Metropolitan Area ◽  
Salt Lake ◽  
Salt Lake City ◽  
Ground Shaking ◽  
Earthquake Scenario ◽  
Lake City

The 18 March 2020 M 5.7 Magna, Utah, Earthquake: Strong-Motion Data and Implications for Seismic Hazard in the Salt Lake Valley

2021 ◽  
Author(s):  
Ivan Wong ◽  
Qimin Wu ◽  
James C. Pechmann
Keyword(s):  
Seismic Hazard ◽  
Fault Zone ◽  
Salt Lake ◽  
Salt Lake City ◽  
Strong Motion ◽  
Ground Shaking ◽  
Fault Segment ◽  
Salt Lake Valley ◽  
Lake City ◽  
Wasatch Fault

Abstract The 2020 oblique normal-faulting M 5.7 Magna mainshock has provided the best dataset of recorded strong ground motions for an earthquake within the Wasatch Front region, Utah, and the larger Basin and Range Province. We performed a preliminary evaluation of the strong motion and broadband data from this earthquake and compared the data with the Next Generation Attenuation - West2 Project (NGA-West2) ground-motion models (GMMs). The highest horizontal peak ground acceleration (PGA) recorded was 0.43g (geometric mean of the two horizontal components) at a station located above the rupture plane at a rupture distance of 8 km. Eleven stations recorded PGAs >0.20g. Most of these stations are located on the deep sedimentary deposits within the Salt Lake Valley, and all are at rupture distances <20  km. The data compare favorably with the NGA-West2 GMMs, although the expected variability was observed. PGAs exceed the GMM predictions at the closest distances for the source model that we used. The area of the strongest ground shaking encompassed the town of Magna, where some of the heaviest damage occurred. A significant implication of the 2020 Magna earthquake for seismic hazards in the Salt Lake Valley arises from the possibility that this earthquake occurred on the Salt Lake City segment of the Wasatch fault. If so, then the dip of this fault segment must decrease with depth to ≤30°–35°, as proposed by Pang et al. (2020)—at least along the northern part of the segment where the earthquake occurred. Because of the lack of information about the subsurface geometry of the Wasatch fault zone, modeling of this fault zone in seismic hazard analyses has assumed a moderate dip of 50°±15°. Assuming a more shallowly dipping fault results in higher estimates of ground shaking in future large earthquakes on this fault. Alternative interpretations of the Magna earthquake are that it occurred (1) on an auxiliary fault within the Wasatch fault zone or (2) on a listric section of the northern Salt Lake City segment that is not representative of the geometry of the whole fault segment.

“Can you take me higher?”: Normative thresholds for air quality in the Salt Lake City Metropolitan area

2019 ◽  
Vol 50 (2) ◽  
pp. 157-180
Author(s):  
Chris A. B. Zajchowski ◽  
Matthew T. J. Brownlee ◽  
Michael Blacketer ◽  
Jeff Rose ◽  
Danya L. Rumore ◽  
...  
Keyword(s):  
Air Quality ◽  
Metropolitan Area ◽  
Salt Lake ◽  
Salt Lake City ◽  
Lake City

Do air quality alerts reduce traffic? An analysis of traffic data from the Salt Lake City metropolitan area, Utah, USA

2013 ◽  
Vol 30 ◽  
pp. 173-185 ◽  
Author(s):  
Calvin P. Tribby ◽  
Harvey J. Miller ◽  
Ying Song ◽  
Ken R. Smith
Keyword(s):  
Air Quality ◽  
Metropolitan Area ◽  
Salt Lake ◽  
Salt Lake City ◽  
Traffic Data ◽  
Lake City
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