A5065730180- earthquake and tectonic studies
- Earthquake Detection and Analysis
- High-pressure geophysics and materials
- Magnetic confinement fusion research
- Seismology and Earthquake Studies
- Seismic Waves and Analysis
- Seismic Imaging and Inversion Techniques
- Ionosphere and magnetosphere dynamics
- Plasma Diagnostics and Applications
- Laser-Plasma Interactions and Diagnostics
- Superconducting Materials and Applications
- Geological and Geochemical Analysis
- Particle accelerators and beam dynamics
- Electronic Packaging and Soldering Technologies
- Solar and Space Plasma Dynamics
- Fusion materials and technologies
- Drilling and Well Engineering
- Intermetallics and Advanced Alloy Properties
- Hydraulic Fracturing and Reservoir Analysis
- Physics of Superconductivity and Magnetism
- Geological and Geophysical Studies Worldwide
- Geological and Geophysical Studies
- 3D IC and TSV technologies
- Geological and Tectonic Studies in Latin America
- Reservoir Engineering and Simulation Methods
University of Tsukuba
2016-2025
Life University
2019-2020
Fujifilm (Japan)
2017
Nagoya University
1976-2016
The University of Tokyo
1998-2014
International Institute of Earthquake Engineering and Seismology
2003-2014
Institute of Seismology
2003-2014
Kyoto University
2012
Hokkaido University
2012
Toyota Central Research and Development Laboratories (Japan)
2006-2011
Abstract A devastating doublet of earthquakes with moment magnitude M W 7.9 and 7.6 contiguously occurred in SE Türkiye near the NW border Syria. Here we perform a potency‐density tensor inversion to simultaneously estimate rupture evolution fault geometry for doublet. We find initial earthquake involved discrete episodes supershear back‐rupture propagation, was triggered by along bifurcated splay East Anatolian Fault. The second event earlier event, it more extensive favorably curved fault,...
Abstract A devastating earthquake with moment magnitude 7.5 occurred in the Noto Peninsula central Japan on 1 January 2024. We estimate rupture evolution of this from teleseismic P‐wave data using potency‐density tensor inversion method, which provides information spatiotemporal slip distribution including fault orientations. The results show a long and quiet initial phase that overlaps regions preceding swarms associated aseismic deformation. following three major episodes evolve segmented,...
[1] On 11 March 2011, the Tohoku-oki earthquake in eastern Japan and devastating tsunami that followed it caused severe damage numerous deaths. To clarify rupture process of earthquake, we inverted teleseismic P-wave data applying a novel formulation takes into account uncertainty Green's function, which has been major error source waveform inversion. The estimated seismic moment is 5.7 × 1022 Nm (Mw = 9.1), associated with fault 440 km long 180 wide along plate interface. characterized by...
In principle, we can never know the true Green's function, which is a major error source in seismic waveform inversion. So far, many studies have devoted their efforts to obtain function as precise possible. this study, propose new strategy cope with problem. That say, introduce uncertainty of into inversion analyses. Due propagation law errors, results data covariance matrix significant off-diagonal components, naturally reduce weight observed later phases. Because depends on model...
The spatio-temporal slip distribution of the 2003 Tokachi-oki, Japan, earthquake was estimated from teleseismic body wave and strong ground motion data. To perform stable inversion, we applied smoothing constraints to with respect time space, determined optimal weights using an optimized Akaike's Bayesian Information Criterion (ABIC). We found that rupture propagates mainly along dip direction, length area is shorter than its width. mean rise in shallow asperity significantly longer deep...
Research Article| April 06, 2016 The Earthquake‐Source Inversion Validation (SIV) Project P. Martin Mai; Mai aKing Abdullah University of Science and Technology, Division Physical Sciences Engineering, Thuwal 23955‐6900, Kingdom Saudi Arabiamartin.mai@kaust.edu.sa Search for other works by this author on: GSW Google Scholar Danijel Schorlemmer; Schorlemmer bGeo‐Forschungszentrum Potsdam, GFZ, Telegrafenberg, 14473 Germany Morgan Page; Page cU.S. Geological Survey, 525 South Wilson Avenue,...
Abstract We compared spatiotemporal slip‐rate and high‐frequency (around 1 Hz) radiation distributions from teleseismic P wave data to infer the seismic rupture process of 2015 Gorkha, Nepal, earthquake. For these estimates, we applied a novel waveform inversion formulation that mitigates effect Green's functions uncertainty hybrid backprojection method contamination by depth phases. Our model showed dynamic front propagated eastward hypocenter at 3.0 km/s triggered large‐slip event centered...
We constructed the rupture process model for 2016 Kumamoto, Japan, earthquake from broadband teleseismic body waveforms (P-waves) by using a novel waveform inversion method that takes into account uncertainty of Green's function. The estimated source parameters are: seismic moment = 5.1 × 1019 Nm (Mw 7.1), fault length 40 km, and width 15 km. mainshock mainly propagated northeastward epicenter, about 30 along an active strike-slip fault. propagation decelerated terminated near southwest side...
The spatial and temporal slip distribution of the Tecoma ´n, Colima, Mexico earthquake is estimated from near-source strong-motion teleseismic bodywave data.To perform a stable inversion, we applied smoothing constraints determined their optimal relative weights on observed data using an optimized Akaike's Bayesian information criterion (ABIC).The source parameters are as follows: (strike, dip, slip) ס (300Њ, 20Њ, 93Њ), seismic moment M 0 2.3 ן 10 20 N m; duration 30 sec; along-strike...
Abstract The rupture process of the 2014 Iquique, Chile earthquake is inverted from teleseismic P wave data applying a novel formulation that takes into account uncertainty Green's function, which has been major error source in waveform inversion. estimated seismic moment 1.5 × 10 21 Nm ( Mw = 8.1), associated with 140 km long and wide fault along plate interface. characterized by unilateral propagation. During first 20 s, dynamic front propagated hypocenter to large asperity located about...
We analyzed continuous GPS data to investigate the spatial distribution of post-seismic slip associated with two large earthquakes October 19 and December 2, 1996, in Hyuga-nada, Japan. found that moment release due events was comparable co-seismic during earthquakes. The source parameters first event are as follows: = 1.7 × 1019 Nm; maximum 0.06 m at about 50 km northwest from epicenter earthquake; characteristic decay time (= final slip/initial slope) 15 days. For second event, 2.0 0.13...
Abstract The 2015 M w 7.8 Nepal‐Gorkha earthquake with casualties of over 9000 people was the most devastating disaster to strike Nepal since 1934 Nepal‐Bihar earthquake. Its rupture process imaged by teleseismic back projections (BP) seismograms recorded three, large regional networks in Australia, North America, and Europe. source images all three arrays reveal a unilateral eastward rupture; however, propagation directions speeds differ significantly between arrays. To understand spatial...
Abstract In September 2022, two destructive earthquakes of moment magnitude ( M w ) 6.6 (foreshock) and 7.1 (mainshock) occurred in Taitung County, south-eastern Taiwan. To understand their complex rupture processes, we analysed these using the Potency Density Tensor Inversion method, which can stably estimate propagation process, including fault geometry, without overfitting data. The analyses revealed that major foreshock propagated towards shallow depth, a south–southwest direction,...
A devastating doublet of earthquakes with moment magnitude Mw 7.9 and 7.6 contiguously occurred in SE Türkiye near the NW border Syria. Here we perform a potency-density tensor inversion to simultaneously estimate rupture evolution fault geometry for doublet. We find initial earthquake involved discrete episodes supershear back-rupture propagation, was triggered by along bifurcated splay East Anatolian Fault. The second event earlier event, it more extensive favorably curved fault, likely...
The rupture process of the 1999 Turkey earthquake is examined using both near‐field strong motion data and teleseismic body wave data. derived source parameters are as follows: (strike, dip, slip) = (268°, 86°, 180°), nearly pure strike‐slip; seismic moment, Mo 1.7 × 10 20 Nm (Mw 7.4); duration sec; fault length 70 km; width 15 km. characterized by an asymmetric bilateral propagation smooth slip. It consists two major segments, a propagating to west second east. maximum dislocation velocity...
We report the results of an experimental and theoretical international project dedicated to study quasi-single helicity (QSH) reversed field pinch (RFP) plasmas. The has involved several RFP devices numerical codes. It appears that QSH spectra are a robust feature common all experiments. Our expand reinforce evidence formation self-organized states with one dominant helical mode (Ohmic SH state) is approach complementary active control magnetic turbulence improve confinement in steady state RFP.
We calculated static stress changes from the devastating M = 7.6 earthquake that shook Kashmir on 8 October, 2005. mapped Coulomb change target fault planes oriented by assuming a regional compressional regime with greatest principal directed orthogonally to mainshock strike. tested calculation sensitivity varying assumed orientations, target‐fault friction, and depth. Our results showed no impact active Salt Range thrust southwest of rupture. Active faults north Main Boundary near Peshawar...
Geodetic imaging data and seismicwaveformdata have complementary strengthswhen considering the modelling of earthquakes. The former, particularly modern space geodetic techniques such as Interferometric Synthetic Aperture Radar (InSAR), permit high spatial density observation thus fine resolution pattern fault slip; latter provide precise accurate timing information, ability to resolve how that slip varies over time. In order harness these strengths, we propose a method through which two...