Fig. 8
From: Mars core structure—concise review and anticipated insights from InSight
Travel time curves (left) and ray paths (right) for two different Mars seismic models. (Top panels) Sohl and Spohn (1997) model A (SS97a); (bottom panels) Rivoldini et al. (2011) model based on the Dreibus and Wänke (1985) compositional model (R11DW). The diagram shows how the combination of core sizes and wavespeeds at the top of the outer core relative to V S at the base of the mantle affect the gross form of the seismic wave arrivals. The right panels show rays emanating from a seismic source at 0° to stations at 55 and 145°. R11DW features a core shadow to SKS and SKKS due to its lower core wavespeeds, one effect of which is that minor arc SKKS disappears at 130°. The core size affects the travel time of the core reflected arrivals PcP and ScS