Imaging 3D Upper‐Mantle Structure with Autocorrelation of Seismic Noise Recorded on a Transportable Single Station

Autocorrelation R2 on Mars

“…The R 2 Rayleigh waves can travel along any or all great circle paths on the Martian surface and possess travel distances that vary due to the planet's ellipticity ( ε = 0.00589) (J. Xie & Ni, 2019). J. Xie and Ni (2019) discussed the effects of ellipticity on the group velocity estimation of the Earth's orbiting surface waves, concluding that the effects are negligible. Accounting for the travel distance variations of R 2 surface waves, we simulated and then calculated a weighted mean of the synthetic Green's functions for a range of radii between the polar and equatorial radius (3,376.2–3,396.2 km) using the direct solution method (DSM) software (Geller & Takeuchi, 1995; Kawai et al., 2006; Takeuchi et al., 1996).…”

“…The R 2 Rayleigh waves can travel along any or all great circle paths on the Martian surface and possess travel distances that vary due to the planet's ellipticity ( ε = 0.00589) (J. Xie & Ni, 2019). J. Xie and Ni (2019) discussed the effects of ellipticity on the group velocity estimation of the Earth's orbiting surface waves, concluding that the effects are negligible.…”

“…The R 2 Rayleigh waves can travel along any or all great circle paths on the Martian surface and possess travel distances that vary due to the planet's ellipticity (ε = 0.00589) (J. Xie & Ni, 2019). J.…”

“…Global tomography analysis suggested that the long period Rayleigh waves (e.g., >100 s) can be recovered by cross‐correlations of the Earth's hum (Haned et al., 2016; Nishida et al., 2009). This was subsequently extended to extract the Earth orbiting Rayleigh waves from a single‐station‐based autocorrelation to constrain the upper mantle velocity models (Li et al., 2020; J. Xie & Ni, 2019; Schimmel et al., 2018).…”

“…The observation of Rayleigh waves traveling around the Earth once, the phase R 2 , using low-frequency autocorrelation of background free oscillations suggests the potential for a similar analysis for InSight seismic data (Schimmel et al, 2018), which then can be used to constrain Martian upper mantle velocity structure (J. Xie & Ni, 2019). Here, we followed the processing procedures in Bensen et al (2007) to compute and stack the vertical-component autocorrelograms of the SEIS ambient noise data, which were band-pass filtered from 0.005 to 0.01 Hz to retrieve the R 2 surface waves.…”