standing next to giants (without stepping on their toes)
Université de Paris / IPGP
University of Hamburg
Earthquake-free seismology. Using seismic signals created from ocean waves, trucks or just anything for monitoring.
and why you should be interested
Seismic wave propagation in icy ocean worlds
The next years will see the decision for a seismometer-equipped lander on Europa or Titan. We tried to predict what could be measured on Europa, Titan, Enceladus or Ganymede.
Stähler, Simon C., Mark P. Panning, Steven D. Vance, Ralph D. Lorenz, Martin van Driel, Tarje Nissen‐Meyer, and Sharon Kedar. 2018. “Seismic Wave Propagation in Icy Ocean Worlds.” J Geophys. Res.: Planets 123 (1): 206–32. doi:10.1002/2017JE005338.
Fully probabilistic seismic source inversion – Part 2: Modelling errors and station covariances
The long-awaited sequel
How can we construct a Likelihood function for non-Gaussian noise on seismic waveforms? Turns out that the dependable Correlation Coefficient follows a log-normal distribution, so we can use that.
Stähler, Simon C., and Karin Sigloch. 2016. “Fully Probabilistic Seismic Source Inversion – Part 2: Modelling Errors and Station Covariances.” Solid Earth 7 (6): 1521–36. doi:10.5194/se-7-1521-2016.
Performance report of the RHUM-RUM ocean bottom seismometer network around La Réunion, western Indian Ocean
Overview of OBS performance in the RHUM-RUM project, especially in comparison between the German (DEPAS) and the French (INSU) seismometers.
Stähler, S. C., Sigloch, K., Hosseini, K.,
Crawford, W. C., Barruol, G., Schmidt-Aursch, M. C., Tsekhmistrenko, M.,
Scholz, J.-R., Mazzullo, A., and Deen, M.: Performance report of the
RHUM-RUM ocean bottom seismometer network around La Réunion, western
Indian Ocean, Adv. Geosci., 41, 43-63, doi:10.5194/adgeo-41-43-2016,
Fully probabilistic seismic source inversion I - Efficient parametrization
This paper deals with the inverse problem of seismic point source inversion. It describes an efficient parametrization to invert for earthquake depth, moment tensor and source time function using Bayesian inference with Malcolm Sambridge's Neighbourhood Algorithm.
Stähler, S. C. and K. Sigloch (2014): Fully probabilistic seismic source inversion – Part 1: Efficient parametrisation, Solid Earth, 5, 1055-1069
Instaseis: instant global seismograms based on a broadband waveform database
Instaseis is a Python library to calculate broadband seismograms for arbitrary source-receiver configurations, including finite faults and single forces from a stored AxiSEM wavefield.
van Driel, M., Krischer, L., Stähler, S. C., Hosseini, K., and Nissen-Meyer, T. (2015). Instaseis: instant global seismograms based on a broadband waveform database
Solid Earth, 6, 701-717
Monitoring stress changes in a concrete bridge with coda wave interferometry
Coda waves contain information about a large volume around the source and receiver. We use that method to monitor stress changes in a bridge during construction.
Stähler, S. C., E. Niederleithinger, and C. Sens-Schönfelder (2011), Monitoring stress changes in a concrete bridge with coda wave interferometry, Journal of the Acoustical Society of America, 129(4), 1945-1952,
Introductory seismology with animations
Seismic wavefield perturbed by plumes and slabs
This video shows the seismic wavefield of an earthquake in a mantle that contains a subducting slab on the left and an upwelling megaswell-structure on the right. The situation is comparable to Southern America on the left and Africa on the right with the earthquake happening in the Central Atlantic ocean at the mid-ocean ridge.
Note that the velocity anomalies are exaggerated to make the effect more prominent.
Seismic wavefield in the Jovian moon Europa
AxiSEM is able to model seismic wave propagation in terrestrial planets in general. One of the most fascinating objects in the solar system is Europa, with its abysmal ocean below a few kilometers of ice. The structure results in a wavefield that is completely different from what we see on Earth. Most of the wave energy is either contained inside the ice (especially SH-waves) or is reverberating inside the ocean.
Seismic wavefield in the Earth
This video shows the seismic wavefield in the Earth's mantle assuming the velocity depends only on depth.
Seismic wavefield perturbed by a megaswell-structure
This video shows a wavefield in a mantle that contains a megaswell.
© 2022 Simon C. Stähler