A5073115404- earthquake and tectonic studies
- Seismic Waves and Analysis
- Seismic Performance and Analysis
- Seismology and Earthquake Studies
- Landslides and related hazards
- Earthquake Detection and Analysis
- Geology and Paleoclimatology Research
- Atmospheric and Environmental Gas Dynamics
- Porphyrin Metabolism and Disorders
- Methane Hydrates and Related Phenomena
- Geological formations and processes
- Biochemical and Molecular Research
- Geological Modeling and Analysis
- Botany and Geology in Latin America and Caribbean
- Geological Studies and Exploration
- Metalloenzymes and iron-sulfur proteins
- High-pressure geophysics and materials
- Geophysics and Sensor Technology
- Geological and Geochemical Analysis
- Geochemistry and Geologic Mapping
United States Geological Survey
2017-2024
Denver Federal Center
2023-2024
Geologic Hazards Science Center
2024
Michigan Technological University
2013
Eastern Washington University
1998
The US National Seismic Hazard Model (NSHM) was updated in 2023 for all 50 states using new science on seismicity, fault ruptures, ground motions, and probabilistic techniques to produce a standard of practice public policy other engineering applications (defined return periods greater than ∼475 or less ∼10,000 years). Changes time-independent seismic hazard (both increases decreases compared previous NSHMs) are substantial because the model considers more data earthquake rupture forecasts...
ABSTRACT We present the 2023 U.S. Geological Survey time-independent earthquake rupture forecast for conterminous United States, which gives authoritative estimates of magnitude, location, and time-averaged frequency potentially damaging earthquakes throughout region. In addition to updating virtually all model components, a major focus has been provide better representation epistemic uncertainties. For example, we have improved multifault ruptures, both in terms allowing more less fault...
We update the ground-motion characterization for 2023 National Seismic Hazard Model (NSHM) conterminous United States. The includes use of new models (GMMs) in Cascadia subduction zone; an adjustment to central and eastern States (CEUS) GMMs reduce misfits with observed data; updated boundary application shallow, crustal earthquakes active tectonic regions (i.e. western (WUS)) stable continental CEUS); improved site response deep sedimentary basins WUS CEUS. Site updates include basin...
The Alaska Volcano Observatory (AVO) responded to eruptions, possible volcanic unrest, or suspected unrest at 11 centers in during 2012. Of the two verified one (Cleveland) was clearly magmatic and other (Kanaga) most likely a single phreatic explosion. Two volcanoes had notable seismic swarms that probably were caused by intrusions (Iliamna Little Sitkin). For each period of clear AVO staff increased monitoring vigilance as needed, reviewed eruptive histories question help evaluate...
The Alaska Volcano Observatory (AVO) responded to eruptions, possible volcanic unrest or suspected at 12 centers in during 2010. most notable activity consisted of intermittent ash emissions from long-active Cleveland volcano the Aleutian Islands. AVO staff also participated hazard communication regarding eruptions seven volcanoes Russia as part an ongoing collaborative role Kamchatka and Sakhalin Volcanic Eruption Response Teams.
Abstract As part of the U.S. Geological Survey’s 2023 50-State National Seismic Hazard Model (NSHM), we make modest revisions and additions to central eastern (CEUS) fault-based seismic source model that result in locally substantial hazard changes. The CEUS was last updated as 2014 NSHM considered new information from Source Characterization for Nuclear Facilities (CEUS-SSCn) Project. Since then, geologic investigations have led revised fault fault-zone inputs, release databases sources...
The US Geological Survey National Seismic Hazard Models (NSHMs) are used to calculate earthquake ground-shaking intensities for design and rehabilitation of structures in the United States. most recent 2014 2018 versions NSHM conterminous States included major updates ground-motion models (GMMs) active stable crustal tectonic settings; however, subduction zone GMMs were largely unchanged. With development next generation attenuation-subduction (NGA-Sub) GMMs, progress utilization “M9”...
Abstract The last National Seismic Hazard Model (NSHM) for Puerto Rico and the U.S. Virgin Islands (PRVI) was published in 2003. In advance of 2025 PRVI NSHM update, we created three geologic input databases to summarize new onshore offshore fault source information northern Caribbean region between 62°–70° W 16°–21° N. These databases, sections, fault-zone polygons, estimates activity (fault-slip rate earthquake recurrence intervals) at specific sites, document updates parameters used prior...
ABSTRACT The time-averaged shear-wave velocity in the upper 30 m depth from ground surface, or VS30, is often used as a predictor to describe local site effects ground-motion models. Although VS30 typically determined situ measurements, it not always feasible obtain such measurements due project restrictions accessibility. This motivates development and use of proxy-based predictions that leverage more readily available secondary information surface geology, topographic slope, geomorphic...
Fourier transform infrared (FTIR) spectra have been obtained from solution samples of the heterocycles uracil, lumazine, and violapterin reveal interpretable carbonyl stretching frequencies. Spectra conjugate bases lumazine demonstrate decreases in these frequencies upon ionization. Based on isotopic shifts amide deuterated analogs, semiempirical QCFF/PI calculations were used to assign vibrational region 1100–1800 cm−1 observed dimethylsulfoxide (DMSO) aqueous solutions specific normal...
US Geological Survey (USGS) National Seismic Hazard Models (NSHMs) are used extensively for seismic design regulations in the United States and earthquake scenario development, as well risk assessment mitigation both buildings infrastructure. This 2023 update of long-term, time-independent Alaska NSHM includes substantial changes to rupture forecast (ERF) ground motion models (GMMs). The ERF numerous additions finite-fault model, considers two deformation models, introduces updated...
ABSTRACT New seismic stations added to a regional network cannot be used calculate local magnitude (ML) until revised regionwide amplitude decay function is developed. Each station must record minimum number of and earthquakes that meet specific requirements prior recalibration the function. Station component adjustments (dML; Uhrhammer et al., 2011) are then calculated after inverting for new function, constrained by sum dML long-running stations. Therefore, there can significant delay...
Correction| July 06, 2021 Erratum toVS30 and Dominant Site Frequency fd as Provisional Station ML Corrections dML in California Alan Yong; Yong * 1U.S. Geological Survey, Pasadena, California, U.S.A. *Corresponding author: yong@usgs.gov https://orcid.org/0000-0003-1807-5847 Search for other works by this author on: GSW Google Scholar Elizabeth Cochran; Cochran https://orcid.org/0000-0003-2485-4484 Jennifer Andrews; Andrews 2California Institute of Technology, Kenneth Hudson; Hudson...