Abstract It has been proposed that the deep Martian mantle contains distributed heterogeneities preserved since the accretion of the planet. This result relies on a multiple‐scattering interpretation of frequency‐dependent arrival times of ‐waves detected in the spectrograms of teleseismic Martian events. In this work, I present a simple envelope‐based methodology to measure arrival times of ‐wave signals characteristic of Mars and systematically investigate high‐frequency data. Besides teleseismic events, I report the detection of frequency‐dependent ‐wave arrival times for three regional events, with a different behavior between the vertical and horizontal components. I critically examine the possibility to explain these observations with scattering theory and conclude that it is incompatible with the data. Instead, I propose that the observations result from a detection threshold effect for weak emergent signals. My analysis calls into question the scattering interpretation of frequency‐dependent arrival times and the presence of heterogeneities in the Martian mantle.
L. Margerin (Wed,) studied this question.