Mantle support for Middle Atlas topography: refining tomographic images by including anisotropy

The topography of the Middle Atlas Mountains in Morocco is known to not be isostatically supported by a crustal root. Instead, support from hot, buoyant asthenospheric mantle has been proposed based on petrological analysis of basalt, mantle flow modelling, and S receiver function analysis. The source of this anomalously hot mantle has been hypothesized to be the Canary plume. Indeed, P-wave tomography has shown a low-velocity anomaly beneath the mountains at depths of 75-200 km, and shear wave splitting is indicative of mantle flow consistent with a Canary origin. However, when we consider the anisotropy evident from shear-wave splitting and incorporate it in the P-wave imaging, the magnitude of the low-velocity anomaly is reduced. These reduced anomaly amplitudes affect the estimated temperature anomaly. In this work, we explore how much of the apparent low-velocity anomaly in isotropic P-wave tomography models can be explained by anisotropy and the implications for determining the origin of the anomalous asthenospheric mantle supporting the Middle Atlas elevations.