devel branch has been updated with the example added here:
github.com/SPECFEM/spec...
devel branch has been updated with the example added here:
github.com/SPECFEM/spec...
SPECFEM3D Cartesian on the Moon - on April 19, 1972, the Apollo 16 S-IVB rocket booster was sent on collision with the Moon for a seismic experiment to study Moon's interior. Simulation includes subsurface scatterers and Apollo 12 seismic station #specfem3d
not yet - a similar example setup for the Mendocino Mw7.0 event is explained on the devel branch of SPECFEM3D Cartesian (github.com/SPECFEM/spec...)
will add this example soon...
:) with this app you could get some more, closer stations from the Berkley network on your phone when you select the NCEDC FDSN web server: apps.apple.com/us/app/wiggl...
when a SPECFEM developer has a summer holiday project.. check out seismic wiggles :) apps.apple.com/us/app/wiggl... #Wiggles #FDSNstationmonitor #iOS
vertical displacement of station AB.HASN
vertical displacement of station AB.YNKD
vertical displacement of station IU.GNI
air strike reported on June 22, 2025, 2:30am local time (23:00 UTC on 2025-06-21) - not much visible in available data at closest stations AB.HASN, AB.YNKD and IU.GNI (~500-800 km away from Fordow site). main signal visible between 21:45-22:15 UTC is a Mw6.0 earthquake (epicenter in Japan)
#specfem3d peak-ground motion (PGV) shakemap of the time-reversal simulation of the Birch glacier collapse. it should highlight the event site - but sometimes things are not so simple.
#specfem3d time-reversal simulation of the Birch glacier collapse. Reinjecting seismic data from all available Swiss broadband stations together with the velocity model from Diehl et al. (2021) pinpoints the source of all that seismic energy...
New ChEESE Codes Interview: SPECFEM!
Ever wondered how we βseeβ whatβs happening beneath the Earthβs surface?
In our latest video, Vadim Monteiller (CNRS) introduces SPECFEM, a powerful seismic simulation tool used in a wide range of applications.
βΆοΈ Watch it here: youtu.be/m7xLVR7YOr4?...
Join us this summer from August 4-7, 2025, in Breckenridge, Colorado, to explore the science and computational challenges that underpin our understanding of Earthβs dynamical systems. For more information about CIG The Next Generation from, see our website: geodynamics.org/events/detai...
Spectral accelerations (SA) at the Bangkok building collapse site based on the synthetics of the updated USGS finite-fault solution of the Myanmar Mw7.7 earthquake #specfem3d #USGS
#shakemovie simulation with the updated USGS finite-fault solution of the Myanmar Mw7.7 #earthquake w/ USGS Vs30 and EarthScope EMC FWEA23 (Liu et al. 2024) model #specfem3d #USGS #EarthScope #blender
PGV shakemap for the Myanmar Mw7.7 earthquake using the updated version of the USGS finite-fault solution
PGV shakemap for the Myanmar Mw7.7 #earthquake based on the updated version of the USGS finite-fault solution #specfem3d #shakemap #USGS
PGV shakemap for the Myanmar Mw7.7 earthquake
PGV shakemap for the Myanmar Mw7.7 #earthquake based on USGS finite-fault solution #specfem3d #shakemap
2025-03-28 Myanmar Mw7.7 #earthquake - shakemovie simulation w/ USGS finite-fault solution and IRIS EMC GLAD-M35 (Cui et al. 2024) model #specfem3d #shakemovie #geoscience #USGS #EarthScope #blender #b3d
Last Friday, two strong Mw6.2 earthquakes struck near Panama and Alaska - just ~3 minutes apart - followed by a smaller Mw5.7 quake. As if Panama and Alaska decided to sync up.. hereβs a #shakeMovie visualization - watch as they light up the Earth with some nice fringes #specfem3dGLOBE
screenshot of google scholar page of SPECFEM hitting 30k+ citations
#SPECFEM codes hit 30,000+ citations!
awkward moment. when your simulation software has a bigger social circle than you do and your code is more popular than youβll ever be. π well done Dimitri.
specfem.org
:) right, thatβs really more due to the choice of using an integer to represent your date rather than a Fortran limit. the same wouldβve happened using other programming languages such as C/C++, C#, Java, .. as they all use mostly 32-bit integers by default these days.
π¨ New #Training!
Learn how to use the SPECFEM code to run 2D and 3D full-wave simulations, perfect for seismology and underwater acoustics applications.
π April 22β23, 2025
π Nantes UniversitΓ©
π€ With SEASOUNDS and NuTS
β‘οΈ Register by Jan 29: cheese2.eu/event/artifi...
sure, happy to provide more details π
the differences here with the wavefronts are due to differences in the earthquake source description, i.e., between a single centroid (CMT) source www.sciencedirect.com/science/arti...
vs. a finite-fault description earthquake.usgs.gov/data/finitef...
for comparison, this simulation is using the same mesh resolution, but with flat topography and just a single centroid-moment tensor (CMT) source. the noisy scattering pattern is mostly due to the USGS finite-fault solution that uses 147 single point sources with interfering wavefields.
might be - this is still a very simplistic model and the finite-element mesh is rather coarse. the spectral-element method however doesn't necessarily need further smoothing.
I guess part of the grid structure you notice is also just due to the visualization...
:) not all of it are artifacts - the main numerical noise are the small reflections of the absorbing boundaries, mostly visible after the strong surface waves hit the box walls. the overalll small-scale scattering you see is not artifacts, but scattering due to the strong topography in this region.
Peak-Ground Velocity (PGV) shakemap for the Shigatse Mw 7.1 earthquake.
PGV shakemap for the Shigatse Mw 7.1 #earthquake based on USGS finite-fault solution #specfem3d #shakemap
2025-01-07 Shigatse Mw 7.1 #earthquake - shakemovie simulation w/ USGS finite-fault solution and IRIS EMC GLAD-M35 (Cui et al. 2024) model #specfem3d #shakemovie #geoscience #USGS #IRIS #EarthScope #blender #b3d
PGV shakemap using USGS VS30 near-surface model in local simulation for the city of Freiburg, Germany, of the Waldkirch 2004 Mw4.7 event
PGV shakemap without VS30 near-surface model of the Waldkirch 2004 Mw4.7 event
Peak-Ground Velocity (PGV) maps do care about small-scale effects - here's using the local simulation with and without the USGS VS30 near-surface velocity model (background regional model from IRIS EMC LSP_Eucrust1.0, Lu et al. 2018)
#specfem3d example of computing the shaking of the 2004 Dec. 5 Waldkirch event (~Mw4.7) in the nearby city of Freiburg, Germany, by injecting the regional wavefield into a very small-scale local simulation (grid point spacing ~15m) - wavefield injection from regional into local SPECFEM3D
interesting, thanks for checking it out!