JpGU-AGU Joint Meeting 2020

Presentation information

[E] Oral

P (Space and Planetary Sciences ) » P-PS Planetary Sciences

[P-PS05] Planetary Seismic Exploration-From InSight and Apollo to Future Missions-

convener:Taichi Kawamura(Institut de Physique du Globe de Paris), Takeshi Tsuji(Department of Earth Resources Engineering, Kyushu University), Ralph Lorenz(Johns Hopkins University Applied Physics Laboratory), William Bruce Banerdt(Jet Propulsion Laboratory)

[PPS05-03] “Time-reversal” inversion of InSight seismogram for quake estimation

*Nobuaki Fuji1, Alice Jacob1, Clément Perrin1, Éléonore Stutzmann1, Philippe Lognonné1, Mark Panning3, Bruce Banerdt3, Simon Stähler2, Martin van Driel2, Savas Ceylan2, Mélanie Drilleau1, Taichi Kawamura1 (1.Université de Paris, Institut de physique du globe de Paris, 2.ETH Zürich, 3.NASA Jet Propulsion Laboratory)

Keywords:InSight, waveform inversion , Regolith

We re-define time-reversal inversion (back projection) operator that can infer the source location. When we have a good coverage of seismic stations and a robust knowledge on the structure, a classical time-reversal, which cross-correlates observed data and synthetic Green’s functions should work. Due to a poor configuration of one-station seismology in InSight project, however, we need to explicitly include the inverse of the full Hessian matrix in order to detect quakes. We have proven this with synthetic tests using 1D Mars models with/without regolith layers on the top of the planet with an explosion source exerted on the surface. We then applied this method to the real data, especially that of “A” quality, with a set of vertical Green’s functions with an explosion source on the surface in order to roughly estimate the distance, which matches the catalog given by the Marsquake Service. We then extend this method for refining the solution using Green’s functions for all the components.