@article {2621,
	title = {Paleoseismic Results from the Alpine Site, Wasatch Fault Zone: Timing and Displacement Data for Six Holocene Earthquakes at the Salt Lake City{\textendash}Provo Segment Boundary},
	journal = {Bulletin of the Seismological Society of America},
	year = {2018},
	month = {Feb-10-2018},
	abstract = {To improve the characterization of Holocene earthquakes on the Wasatch fault zone (WFZ), we conducted light detection and ranging (lidar)-based neotectonic mapping and excavated a paleoseismic trench across an 8-m-high fault scarp near Alpine, Utah, located <1  km south of the boundary between the Salt Lake City and Provo segments (SLCS and PS). We document evidence for six paleoearthquakes (AL6{\textendash}AL1) from scarp-derived colluvial wedges and crosscutting relations. A ground-penetrating radar survey across the scarp resolved fault-zone width, but not paleoearthquake stratigraphy. Bayesian (OxCal) modeling of 13 radiocarbon and 13 optically stimulated luminescence ages indicates that six earthquakes occurred \~{}6.2{\textendash}0.4  ka. Interseismic recurrence ranges from 0.2 to 1.8 ky (mean 1.2 ky). We estimate 6.5{\textpm}0.7  m of cumulative vertical tectonic displacement across the >=14-m-wide fault zone used near-field observations of scarp-derived colluvial-wedge thicknesses, antithetic faulting, and graben backtilting. This is similar to our independent estimate of 6.5{\textpm}0.5  m using far-field observations of the offset ground surface and correlation of alluvial-fan stratigraphy across the WFZ. These results suggest that colluvial-wedge thickness at the Alpine site approximates one-half the original west-facing fault scarp height. Per-event vertical displacements range from 0.8 to 1.2 m (mean 1.1 m), which we use to estimate surface rupture lengths that may exceed 50 km from earthquakes as large as moment magnitude (Mw) \~{}7.0. The late Holocene average vertical slip rate is 0.9  mm/yr (0.7{\textendash}1.2  mm/yr range). Earthquake frequency has increased in the past \~{}1  ky, whereas displacement per event has been similar for the past \~{}6  ky, suggesting that strain accumulation is not the sole factor that controls the frequency and size of earthquakes at the SLCS{\textendash}PS segment boundary. These findings can be used for a more nuanced characterization of earthquakes at the SLCS{\textendash}PS boundary and improve earthquake hazard assessments along the Wasatch Front.},
	issn = {0037-1106},
	doi = {10.1785/0120160358},
	url = {https://pubs.geoscienceworld.org/ssa/bssa/article/556954/Paleoseismic-Results-from-the-Alpine-Site-Wasatch},
	author = {Bennett, S. E. K. and DuRoss, C. B. and Gold, R. D. and Briggs, R. W. and Personius, S. F. and Reitman, N. G. and Devore, J. R. and Hiscock, A. I. and Mahan, S. A. and Gray, H. J. and Gunnarson, S. and Stephenson, W. J. and Pettinger, E. and Odum, J. K.}
}
@article {2592,
	title = {Holocene earthquakes and right-lateral slip on the left-lateral Darrington-Devils Mountain fault zone, northern Puget Sound, Washington},
	journal = {Geosphere},
	volume = {10},
	year = {2014},
	month = {Jan-12-2014},
	pages = {1482 - 1500},
	abstract = {Sources of seismic hazard in the Puget Sound region of northwestern Washington include deep earthquakes associated with the Cascadia subduction zone, and shallow earthquakes associated with some of the numerous crustal (upper-plate) faults that crisscross the region. Our paleoseismic investigations on one of the more prominent crustal faults, the Darrington{\textendash}Devils Mountain fault zone, included trenching of fault scarps developed on latest Pleistocene glacial sediments and analysis of cores from an adjacent wetland near Lake Creek, 14 km southeast of Mount Vernon, Washington. Trench excavations revealed evidence of a single earthquake, radiocarbon dated to ca. 2 ka, but extensive burrowing and root mixing of sediments within 50{\textendash}100 cm of the ground surface may have destroyed evidence of other earthquakes. Cores in a small wetland adjacent to our trench site provided stratigraphic evidence (formation of a laterally extensive, prograding wedge of hillslope colluvium) of an earthquake ca. 2 ka, which we interpret to be the same earthquake documented in the trenches. A similar colluvial wedge lower in the wetland section provides possible evidence for a second earthquake dated to ca. 8 ka. Three-dimensional trenching techniques revealed evidence for 2.2 {\textpm} 1.1 m of right-lateral offset of a glacial outwash channel margin, and 45{\textendash}70 cm of north-side-up vertical separation across the fault zone. These offsets indicate a net slip vector of 2.3 {\textpm} 1.1 m, plunging 14{\textdegree} west on a 286{\textdegree}-striking, 90{\textdegree}-dipping fault plane. The dominant right-lateral sense of slip is supported by the presence of numerous Riedel R shears preserved in two of our trenches, and probable right-lateral offset of a distinctive bedrock fault zone in a third trench. Holocene north-side-up, right-lateral oblique slip is opposite the south-side-up, left-lateral oblique sense of slip inferred from geologic mapping of Eocene and older rocks along the fault zone. The cause of this slip reversal is unknown but may be related to clockwise rotation of the Darrington{\textendash}Devils Mountain fault zone into a position more favorable to right-lateral slip in the modern N-S compressional stress field.},
	doi = {10.1130/GES01067.1},
	url = {https://pubs.geoscienceworld.org/geosphere/article/10/6/1482-1500/132254},
	author = {Personius, S. F. and Briggs, R. W. and Nelson, A. R. and Schermer, E. R. and Maharrey, J. Z. and Sherrod, B. L. and Spaulding, S. A. and Bradley, L.-A.}
}
@article {1362,
	title = {Field and laboratory data from an earthquake history study of scarps of the Lake Creek-Boundary Creek fault between the Elwha River and Siebert Creek, Clallam County, Washington},
	year = {2007},
	note = {id: 433},
	month = {2007},
	author = {Nelson, A. R. and Personius, S. F. and Buck, Jason and Bradley, L. A. and Wells, R. E. and Schermer, E. R.}
}
@article {1359,
	title = {Paleoseismology of the Nephi segment of the Wasatch fault zone, Juab County, Utah--Preliminary results from two large exploratory trenches at Willow Creek},
	year = {2007},
	note = {id: 1116; Investigations Map 2966, 2 oversize plates},
	month = {2007},
	publisher = {U. S. Geological Survey},
	author = {Machette, M. N. and Crone, A. J. and Personius, S. F. and Dart, R. L. and Lidke, D. J. and Mahan, S. A. and Olig, S. S.}
}
@article {723,
	title = {Evidence for Late Holocene earthquakes on the Utsalady Point Fault, northern puget lowland, Washington},
	journal = {Bulletin of the Seismological Society of America},
	volume = {94},
	year = {2004},
	note = {887giTimes Cited:18Cited References Count:46},
	month = {Dec},
	pages = {2299-2316},
	abstract = {Trenches across the Utsalady Point fault in the northern Puget Lowland of Washington reveal evidence of at least one and probably two late Holocene earthquakes. The "Teeka"{\textquoteright} and "Duffers" trenches were located along a 1.4-km-long. 1- to 4-m-high, northwest-trending, southwest-facing. topographic scarp recognized from Airborne Laser Swath Mapping. Glaciomarine drift exposed in the trenches reveals evidence of about 95 to 150 cm of vertical and 200 to 220 cm of left-lateral slip in the Teeka trench. Radiocarbon ages from a buried soil A horizon and overlying slope colluvium alone, with the historical record of earthquakes suggest that this faulting occurred 100 to 400 calendar years B.P. (A.D. 1550 to 1850). In the Duffers trench, 370 to 450 cm of vertical separation is accommodated by faulting (similar to210 cm) and folding (similar to160 to 240 cm), with probable but undetermined amounts of lateral slip. Stratigraphic relations and radiocarbon ages from buried soil, colluvium. and fissure fill in the hanging wall suggest the deformation at Duffers is most likely from two earthquakes that occurred between 100 to 500 and 1100 to 2200 calendar years B.P., but deformation during a single earthquake is also possible. For the two-earthquake hypothesis, deformation at Teeka trench in the first event involved folding but not faulting. Regional relations suggest that the earthquake(s) were M greater than or equal to similar to6.7 and that offshore rupture may have produced tsunamis. Based on this investigation and related recent studies, the maximum recurrence interval for large ground-rupturing crustal-fault earthquakes in the Puget Lowland is about 400 to 600 years or less.},
	issn = {0037-1106},
	doi = {10.1785/0120040050},
	author = {Johnson, S. Y. and Nelson, A. R. and Personius, S. F. and Wells, R. E. and Kelsey, H. N. and Sherrod, B. L. and Okumura, K. and Koehler, R. and Witter, R. C. and Bradley, L. A. and Harding, D. J.}
}
@article {1358,
	title = {Map and data for Quaternary faults and folds in Washington State},
	year = {2003},
	note = {id: 997},
	month = {2003},
	author = {Lidke, D. J. and Johnson, S. Y. and McCory, P. A. and Personius, S. F. and Nelson, A. R. and Dart, R. L. and Bradley, L. A. and Haller, K. M. and Machette, M. N.}
}
@article {1357,
	title = {Maps and data from a trench investigation of the Utsalady Point fault, Whidbey Island, Washington},
	year = {2003},
	note = {id: 996},
	month = {2003},
	author = {Johnson, S. Y. and Nelson, A. R. and Personius, S. F. and Wells, R. E. and Kelsey, H. M. and Sherrod, B. L. and Okumura, K. and Koehler, R., III and Witter, R. C. and Bradley, L. A. and Harding, D. J.}
}
