A5060193501- earthquake and tectonic studies
- Seismology and Earthquake Studies
- Earthquake Detection and Analysis
- High-pressure geophysics and materials
- Seismic Waves and Analysis
- Seismic Performance and Analysis
- Gait Recognition and Analysis
- Geological and Geochemical Analysis
- Seismic Imaging and Inversion Techniques
- Speech and Audio Processing
- Drilling and Well Engineering
- Hydraulic Fracturing and Reservoir Analysis
Planetary Science Institute
2018-2022
University of California, Los Angeles
2018-2022
Dalhousie University
2022
China Earthquake Administration
2021-2022
University of California, Santa Cruz
2019
Institute of Disaster Prevention
2017
Abstract The ever-increasing networks and quantity of seismic data drive the need for seamless automatic workflows rapid accurate earthquake detection location. In recent years, machine learning (ML)-based pickers have achieved remarkable accuracy efficiency with generalization, thus can significantly improve location previously developed sequential methods. However, inconsistent input or output (I/O) formats between multiple packages often limit their cross application. To reduce format...
Abstract The left-lateral strike-slip Xiaojiang fault is an important tectonic boundary between Sichuan–Yunnan diamond block and the Yangtze block, which accommodated several M > 7.0 damaging earthquakes in past ∼500 yr, as well intense deformation. However, seismogenesis of its middle-northern section are not understood due to lack dense stations. In this study, we analyze one year continuous seismic records from November 2019 2020, recorded at a recently deployed array. We build...
Abstract In this study, we build a multi‐station phase‐picking model named EdgePhase by integrating an Edge Convolutional module with state‐of‐the‐art single‐station model, EQTransformer. The module, variant of Graph Neural Network, exchanges information relevant to seismic phases between neighboring stations. EdgePhase, seismograms are first encoded into the latent representations, then converted enhanced representations and finally decoded P‐ S‐phase probabilities. Compared standard...
Research Article| March 19, 2019 Comparison of Site Dominant Frequency from Earthquake and Microseismic Data in California Behzad Hassani; Hassani Corresponding Author aCivil Design, Generation Engineering, BC Hydro, 6911 Southpoint Drive, Edmonds A02, Burnaby, British Columbia, Canada V3N 4X8, Behzad.hassani@bchydro.com Search for other works by this author on: GSW Google Scholar Alan Yong; Yong bDepartment the Interior, U.S. Geological Survey, Science Center, 525 South Wilson Avenue,...
Abstract The Tangshan 1976 M 7.8 earthquake was followed by two large aftershocks (the Luanxian 7.1 and the Ninghe 6.9 earthquake). sequence occurred in an area with good geodetic observation, horizontal vertical co‐seismic displacements were obtained triangulation net leveling net. In this study, using raw data (not subsidence image processed from data) observation data, we obtain rupture distribution of strike slip dip component on seismogenic faults. geometry size seismic faults are...
Abstract Typical ground‐motion prediction equations (GMPEs) measure source‐to‐site distances relative to the closest point on rupture plane ( R rup ). However, for megathrust earthquakes M w > 8), oversimplification of earthquake source characteristics in distance metrics results significant bias. Recent studies suggest that high‐frequency (HF) and low‐frequency (LF) energy tend emanate from different portions megathrusts. This phenomenon motivates an alternative metric based array...
Abstract Foreshock activity sometimes precedes large earthquakes, but how foreshocks relate to mainshock nucleation is still unclear with limited case studies existing. One way further the understanding of foreshock occurrence mechanism maximize resolution characteristics by waveform-based earthquake detection and location. Here, we apply match locate method scan continuous waveforms 30 days before 44 after 2018 ML 4.0 Shimian in Sichuan, China, obtain approximately three times more events...
Abstract An important manifestation of the background or coseismic deformation surrounding megathrust earthquakes is offshore microseismicity, which are difficult to be directly detected by land‐based seismic instruments. Here, we improve capability detecting events combining two popular techniques: backprojection (BP) imaging and matched‐filter (MF) detection. The BP method effective in retrieving seismicity ( M w > 4.5 ) buried coda wave large earthquakes. MF depends on availability...
Supershear earthquakes with rupture velocity exceeding shear-wave speeds, previously observed in laboratory experiments and large strike-slip events, often have an initial sub-shear stage before they transition to supershear. In this study, integrated geophysical observations of the 2018 Mw 7.5 Palu, Indonesia earthquake, provide robust evidence early persistent supershear speed. Slowness-enhanced back-projection (SEBP) teleseismic data provides a sharp image process, consistently across...