A5013533910- earthquake and tectonic studies
- Seismology and Earthquake Studies
- Geological and Geochemical Analysis
- Earthquake Detection and Analysis
- Seismic Waves and Analysis
- Geology and Paleoclimatology Research
- High-pressure geophysics and materials
- Seismic Performance and Analysis
- Seismic Imaging and Inversion Techniques
- Landslides and related hazards
- Geological and Geophysical Studies Worldwide
- Geochemistry and Geologic Mapping
- Geophysics and Sensor Technology
- Archaeology and ancient environmental studies
- Geological formations and processes
- Geological Modeling and Analysis
- Hydrocarbon exploration and reservoir analysis
- Anomaly Detection Techniques and Applications
- Software System Performance and Reliability
- Hydraulic Fracturing and Reservoir Analysis
- Geological and Geophysical Studies
- Marine and environmental studies
- Time Series Analysis and Forecasting
- Structural Response to Dynamic Loads
- Concrete Corrosion and Durability
United States Geological Survey
2017-2025
Earthquake Science Center
2017-2023
University of Nevada, Reno
2010-2021
University of Oregon
1992-1994
The 2014 Working Group on California Earthquake Probabilities (WGCEP14) present the time‐independent component of Uniform Rupture Forecast, Version 3 (UCERF3), which provides authoritative estimates magnitude, location, and time‐averaged frequency potentially damaging earthquakes in California. primary achievements have been to relax fault segmentation include multifault ruptures, both limitations UCERF2. rates all are solved for simultaneously from a broader range data, using system‐level...
The scarcity of long geological records major earthquakes, on different types faults, makes testing hypotheses regular versus random or clustered earthquake recurrence behavior difficult. We provide a fault-proximal record spanning 8000 years the strike-slip Alpine Fault in New Zealand. Cyclic stratigraphy at Hokuri Creek suggests that fault ruptured to surface 24 times, and event ages yield 0.33 coefficient variation interval. associate this near-regular with geometrically simple fault,...
The 2014 Working Group on California Earthquake Probabilities (WGCEP 2014) presents time-dependent earthquake probabilities for the third Uniform Rupture Forecast (UCERF3). Building UCERF3 time-in- dependent model published previously, renewal models are utilized to represent elastic- rebound-implied probabilities. A new methodology has been developed that solves applicability issues in previous approach unsegmented models. meth- odology also supports magnitude-dependent aperiodicity and...
Abstract We analyze a set of 76 mapped surface ruptures for relationships between geometrical discontinuities in fault traces and earthquake rupture extent. The combined includes 46 strike‐slip, 16 normal, 14 reverse mechanism events. survey shows ∼90% have at least one end mappable discontinuity, either or step 1 km greater. Dip‐slip cross larger steps than strike‐slip earthquakes, with maxima ∼12 versus ∼5 km, respectively. Large inside are rare; only 8% (5 62) ≥4 km. A geometric...
The concept of the earthquake cycle is so well established that one often hears statements in popular media like, "the Big One overdue" and longer it waits, bigger will be."Surprisingly, data to critically test variability recurrence intervals, rupture displacements, relationships between two are almost nonexistent.To generate a long series intervals offsets, we have conducted paleoseismic investigations across San Andreas fault near town Wrightwood, California, excavating 45 trenches over...
In this report we present the time-independent component of Uniform California Earthquake Rupture Forecast, Version 3 (UCERF3), which provides authoritative estimates magnitude, location, and time-averaged frequency potentially damaging earthquakes in California. The primary achievements have been to relax fault segmentation assumptions include multifault ruptures, both limitations previous model (UCERF2). rates all are solved for simultaneously, from a broader range data, using system-level...
Research Article| October 10, 2017 Bends and Ends of Surface Ruptures Glenn P. Biasi; Biasi aUniversity Nevada, Reno, Nevada Seismological Laboratory, MS‐174, 89557, glenn@unr.eduwesnousky@unr.edu Search for other works by this author on: GSW Google Scholar Steven G. Wesnousky bUniversity Center Neotectonic Studies, MS‐169, 89557cAlso at University 89557. Author Article Information Publisher: Society America First Online: 10 Oct Online Issn: 1943-3573 Print 0037-1106 Bulletin the (2017) 107...
Research Article| July 12, 2017 A Synoptic View of the Third Uniform California Earthquake Rupture Forecast (UCERF3) Edward H. Field; Field aU.S. Geological Survey, Denver Federal Center, P.O. Box 25046, MS‐966, Denver, Colorado 80225‐0046 U.S.A., field@usgs.gov Search for other works by this author on: GSW Google Scholar Thomas Jordan; Jordan bUniversity Southern California, 3651 Trousdale Parkway Number 169, Los Angeles, 90089‐0742 Morgan T. Page; Page cU.S. 525 S. Wilson Avenue, Pasadena,...
We present a method to estimate paleomagnitude and rupture extent from measurements of displacement at single point on fault. The variability historic ruptures is summarized in histogram normalized slip, then scaled give the probability finding given within for any magnitude considered. can be inverted assuming earthquake as likely another, yielding density functions length measurement. To improve these distributions we include term account that would cause ground two alternative magnitude....
Research Article| June 01, 2010 Quasi-periodic recurrence of large earthquakes on the southern San Andreas fault Katherine M. Scharer; Scharer * 1Department Geology, Appalachian State University, Boone, North Carolina 28608, USA *E-mail: scharerkm@appstate.edu. Search for other works by this author on: GSW Google Scholar Glenn P. Biasi; Biasi 2Seismological Laboratory, University Nevada-Reno, Reno, Nevada 89557, Ray J. Weldon, II; II 3Department Geological Sciences, Oregon, Eugene, Oregon...
Kappa is a one-parameter estimator of the spectral amplitude decay with frequency seismogram. Low values (∼5 ms) indicate limited attenuation high- energy whereas higher (∼40 high-frequency has been removed. often assumed to be site term and used in seismic designs. We address two key questions about kappa: (1) how identify source, path, contributions kappa; (2) can kappa estimates from smaller earthquakes, more readily accessible weak-motion recordings, reasonably extrapolated esti- mate...
We introduce a quantitative approach to paleoearthquake dating and apply it paleoseismic data from the Wrightwood Pallett Creek sites on southern San Andreas fault. illustrate how stratigraphic ordering, sedimentolog- ical, historical can be used quantitatively in process of estimating earth- quake ages. Calibrated radiocarbon age distributions are directly layer through recurrence intervals probability estimation. The method does not eliminate subjective judgements event dating, but provide...
We present evidence of 11–14 earthquakes that occurred between 3000 and 1500 b.c. on the San Andreas fault at Wrightwood paleoseismic site. Earthquake is presented in a novel form which we rank (high, moderate, poor, or low) quality all ground deformation, are called “event indicators.” Event indicator reflects our confidence morphologic sedimentologic can be attributable to ground-deforming earthquake horizon accurately identified by morphology feature. In four vertical meters section...
Abstract The Alpine fault in south Westland, New Zealand, releases strains of Pacific–Australian relative plate motion large earthquakes with an average interevent spacing ∼330 years. A new record earthquake recurrence has been developed at Hokuri Creek, evidence for 22 events. youngest Creek overlaps time and is believed to be the same as oldest another site about 100 km northwest near Haast. combined spans last 7900 years includes 24 We study rate conditional probability ground ruptures...
Abstract Paleoseismic data on the timing of ground‐rupturing earthquakes constrain recurrence behavior active faults and can provide insight rupture history a fault if dated at neighboring sites overlap in age are considered correlative. This study presents evidence ages for 11 that occurred along Big Bend section southern San Andreas Fault Frazier Mountain paleoseismic site. The most recent earthquake to site was M w 7.7–7.9 Fort Tejon 1857. We use over 30 trench excavations document...
A 220-ka-long M w ≥ 7.0 earthquake record reveals an unexpectedly high seismicity rate on a slow-slipping plate boundary.
ABSTRACT The ShakeAlert earthquake early warning (EEW) system partners along with U.S. Geological Survey (USGS) licensed operators deliver EEW alerts to the public and trigger automated systems when a significant is expected impact California, Oregon, or Washington. ShakeAlert’s primary goal provide usable times before arrival of damaging shaking. most likely achieve this in large-magnitude earthquakes. In recent years, has gone through series upgrades its underlying scientific algorithms...
The San Andreas fault in Calfornia is one of the best studied earthquake-generating faults world. In their Perspective, Weldon et al . discuss recent efforts to construct rupture scenarios, that is, possible histories date, location, and length past earthquakes on fault. Existing knowledge locations dates can be explained by different but authors argue evidence favors hypothesis breaks relatively infrequent, large earthquakes. They caution current 148-year hiatus since last big earthquake...
We present a new method to objectively combine paleoseismic event data from multiple sites into rupture scenarios and apply it the southern San Andreas fault (SSAF) of California. First, pool is constructed all ruptures between allowed by geometry available age probability distribution functions (PDFs). Scenarios drawing this are evaluated average quality agreement dating evidence, degree misfit cumulative displacement over compared prediction slip rate elapsed time, number events in...
Strata and fault relationships revealed in five trenches excavated across the recent trace of Alpine at Haast, Okuru, Turnbull Rivers, South Westland, New Zealand, record three most surface-faulting events.Using back-stripping techniques to remove faulting events sedimentary units associated with restores cross-sections gravel-bed floodplains Haast Okuru about A.D. 750.Horizontal vertical offsets stream channels terrace risers reveal characteristic displacements 8-9 m dextral up 1 per...
ABSTRACT This report documents the assessment by U.S. Geological Survey (USGS) Earthquake Rupture Forecast (ERF) Review Panel of draft ERF for conterminous United States (CONUS-ERF23) proposed 2023 update National Seismic Hazard Model (NSHM23). members participated with Development Team in several verification and validation exercises, including spot checks hazard estimates at key localities. The ERF23 forecast is substantially different from its predecessor, yielding relative differences...
Abstract A new method is presented for using known ordering or other relationships between 14 C samples to reduce dating uncertainty. The order of sample formation often from, example, stratigraphic superposition, dendrochronology, crosscutting field relations. Constraints such as a minimum time dates and limits from historical information are also readily included. Dendrochronologically calibrated calendric date histograms initially represent each date. uses Bayes theorem the relational...