A5067984244- earthquake and tectonic studies
- Geological and Geochemical Analysis
- Astro and Planetary Science
- Earthquake Detection and Analysis
- Seismology and Earthquake Studies
- Planetary Science and Exploration
- High-pressure geophysics and materials
- Seismic Waves and Analysis
- Geology and Paleoclimatology Research
- High-Velocity Impact and Material Behavior
- Geological Modeling and Analysis
- Methane Hydrates and Related Phenomena
- GNSS positioning and interference
- Geomagnetism and Paleomagnetism Studies
- Space Satellite Systems and Control
- Geography Education and Pedagogy
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Geophysics and Sensor Technology
- Rock Mechanics and Modeling
- Geological and Geophysical Studies
- Dynamics and Control of Mechanical Systems
- Resilience and Mental Health
- Fluid Dynamics Simulations and Interactions
- Seismic Imaging and Inversion Techniques
- Granular flow and fluidized beds
University of Hawaiʻi at Mānoa
2013-2024
University of Hawaii System
2015-2023
Lowell Observatory
2015
The University of Texas at El Paso
2008-2014
Scripps Institution of Oceanography
2006-2009
University of Texas Institute for Geophysics
2009
Jet Propulsion Laboratory
2006-2008
We compared four interseismic velocity models of the San Andreas Fault based on GPS observations. The standard deviations predicted secular from are larger north Francisco Bay area, near creeping segment in Central California, and along Jacinto East California Shear Zone Southern California. A coherence spectrum analysis fields indicates relatively high correlation among at longer wavelengths (>15–40 km), with lower shorter wavelengths. To improve short‐wavelength accuracy model, we...
[1] The depth of the seismogenic zone is a critical parameter for earthquake hazard models. Independent observations from seismology and geodesy can provide insight into depths faulting, but these do not always agree. Here we inspect variations in fault 12 segments southern San Andreas Fault System derived over 1000 GPS velocities 66,000 relocated hypocenters. Geodetically determined locking range 6 to 22 km, while thicknesses are largely limited 11–20 km. These best match geodetic when...
Abstract Interferometric Synthetic Aperture Radar is an important tool for imaging surface deformation from large continental earthquakes. Here, we present maps of coseismic displacement and strain the 2019 Ridgecrest earthquakes using multiple Sentinel-1 images. We provide three types interferometric products. (1) Standard interferograms two look directions overview can be used modeling slip. (2) Phase gradient stacks high-resolution (∼30 m) images concentration fracturing that to guide...
Abstract Previous inversions for slip rate along the San Andreas Fault System (SAFS), based on elastic half‐space models, show a discrepancy between geologic and geodetic rates few major fault segments. In this study, we use an earthquake cycle model representing plate over viscoelastic to demonstrate that there is no significant long‐term rates. The California statewide includes 41 segments having steady from base of locked zone episodic shallow known historical ruptures recurrence...
Abstract The Mw 6.4 and 7.1 Ridgecrest earthquake sequence occurred on 4 5 July 2019 within the eastern California shear zone of southern California. Both events produced extensive surface faulting ground deformation Indian Wells Valley Searles Valley. In weeks following earthquakes, more than six dozen scientists from government, academia, private sector carefully documented ground-deformation features. As December 2019, we have compiled a total 6000 observations; approximately 1500 these...
Mapping out backward motion Most deformation associated with an earthquake is, not surprisingly, in the same direction as fault rupture. Xu et al. used satellite imaging to find areas of 2019 Ridgecrest sequence that moved opposite direction. These regions this because inelastic deformation, which helped accommodate overall rupture for sequence. The observations were possible improved radar and are likely more common than previously believed. Science , issue p. 605
Interseismic motion along complex strike-slip fault systems such as the San Andreas Fault System (SAFS) can produce vertical velocities that are ~10 times smaller than horizontal velocities, caused by along-strike variations in orientation and locking depth. Tide gauge stations provide a long (50–100 year) recording history of sea level change due to several oceanographic geologic processes, including earthquake cycle deformation. Here we compare relative displacements with predictions from...
Major ruptures along the San Andreas Fault System (SAFS) are driven by stress that has accumulated in upper locked portion of crust. The present‐day accumulation rate on any given fault segment is fairly well resolved current geodetic measurements. Model rates vary between 0.5 and 7 MPa per century inversely proportional to earthquake recurrence intervals. In contrast, total a poorly since it depends uncertain rupture history each over past few thousand years. We simulate at crustal depths...
[1] Enceladus's south polar thermal anomaly and water-rich plumes suggest the existence of a subsurface ocean, which is overlain by an ice shell uncertain thickness. Our objective to constrain thickness, through assessment tidally driven Coulomb failure tiger stripe faults. We find that thin moderate thicknesses (<40 km) support shear along stripes, assuming low coefficients friction (0.1–0.3) shallow fault depths (<3 km). These results are marginally consistent with minimum thickness can...
Changes in the level of ancient Lake Cahuilla over last 1500 years Salton Trough alter state stress by bending lithosphere response to applied lake load and varying pore pressure magnitude within crust. The recurrence interval is similar rupture on southern San Andreas Jacinto faults, both which are partially covered at its highstand. Furthermore, four five ruptures fault have occurred near a time substantial change. We investigate effect Coulomb perturbations local faults due changing...
Research Article| April 01, 2007 Diffuse interseismic deformation across the Pacific–North America plate boundary Shimon Wdowinski; Wdowinski 1Division of Marine Geology and Geophysics, University Miami, 4600 Rickenbacker Causeway, Florida 33149-1098, USA Search for other works by this author on: GSW Google Scholar Bridget Smith-Konter; Smith-Konter 2Cecil H. Ida M. Green Institute Geophysics Planetary Physics, Scripps Institution Oceanography, La Jolla, California 92093-0210, Yehuda Bock;...
The high demand for scientists and engineers in the workforce means that there is a continuing need more strategies to increase student completion science, technology, engineering, mathematics (STEM) majors. challenge lies finding enacting effective students' of STEM degrees recruiting students these disciplines, especially those from underrepresented minority groups. This article presents results 10 years data collected during 2-week summer program school geosciences targeted at...
Abstract Seismic moment accumulation rate is a fundamental parameter for assessing seismic hazard. It can be estimated geodetically from either fault‐based modeling, or strain rate‐based calculations, where models largely depend on the rheological layering and number of faults. The strain‐rate method depends an unknown (Kostrov) thickness used to convert into rate. In Part 1 this study, we use three published southern California establish value Kostrov such that total approach, calculated...
Abstract A major challenge for understanding the physics of shallow fault creep has been to observe and model long‐term effect stress changes on rate. Here we investigate surface along southern San Andreas (SSAF) using data from interferometric synthetic aperture radar spanning over 25 years (ERS 1992–1999, ENVISAT 2003–2010, Sentinel‐1 2014–present). The main result this analysis is that average rate increased after Landers event then decreased by a factor 2–7 past few decades. We consider...
Abstract The 2019 Ridgecrest conjugate Mw6.4 and Mw7.1 events resulted in several meters of strike‐slip dip‐slip along an intricate rupture, extending from the surface down to 15 km. Now with >2 years post‐rupture observations, we utilize these results better understand vertical postseismic deformation sequence illuminate emerging significance earthquake cycle data. We determine cumulative displacement observed by continuous GNSS network since Ridgecrest, which requires additional time...
The in situ crustal stress field fundamentally governs, and is affected by, the active tectonic processes of plate boundary regions, yet questions remain about characteristics this implications for faults upper crust. We estimate magnitude differential at seismogenic depth southern California by balancing orientation indicated earthquake focal mechanisms against imposed topography, which tends to resist motion strike-slip faults. Our results indicate that most regions require least 20 MPa...
The Gofar oceanic transform fault at the East Pacific Rise has one of best seismic cycles recorded by modern instruments. timing, location, and magnitude major earthquakes (Mw>5.5) have been well constrained data from global networks for past 30 years. earthquake interval is short, about 3-5 Several segments already experienced 5 since 1995, when network was good enough surface wave relocation. Two ocean bottom seismometer deployments (2008-2009, 2021-2023) also provide constraints on...
Abstract Kīlauea Volcano on Hawai'i Island is host to a complex volcanic and interwoven fault system. Over the last ∼120 years, range of seismic events, including large earthquakes such as 1975 7.7 Kalapana earthquake, creep, slow slip have occurred along décollement underlying Kilauea's south flank. We explore both deformation stress changes from 1896 2018 by collating six geodetic data sets creating an analytical model determine dominant sources (i.e., planes, rifts, magma chambers)...
Moment accumulation rate (also referred to as moment deficit rate) is a fundamental quantity for evaluating seismic hazard. The conventional approach of creeping faults invert the slip distribution from geodetic measurements, although even with perfect data these slip-rate inversions are non-unique. In this study, we show that versus depth inversion not needed because can be estimated directly surface data. We propose an integral uses dense observations Interferometric Synthetic Aperture...