Constraints for the Martian Crustal Structure From Rayleigh Waves Ellipticity of Large Seismic Events
Persistent URL: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/11227
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For the first time, we measured the ellipticity of direct Rayleigh waves at intermediate periods (15–35 s) on Mars using the recordings of three large seismic Martian events, including S1222a, the largest event recorded by the InSight mission. These measurements, together with P‐to‐s receiver functions and P‐wave reflection times, were utilized for performing a joint inversion of the local crustal structure at the InSight landing site. Our inversion results are compatible with previously reported intra‐crustal discontinuities around 10 and 20 km depths, whereas the preferred models show a strong discontinuity at ∼37 km, which is interpreted as the crust‐mantle interface. Additionally, we support the presence of a shallow low‐velocity layer of 2–3 km thickness. Compared to nearby regions, lower seismic wave velocities are derived for the crust, suggesting a higher porosity or alteration of the whole local crust.
Rayleigh waves ellipticity was measured between periods 15–35 s at the InSight landing site using large seismic events, including S1222a
A 4‐layer crust, including a shallow low‐velocity layer, is required to explain the ellipticity, receiver functions and P‐wave lag times
Low crustal velocities are derived for the InSight site, which may be due to high porosity or heavy alteration at local scale