The origin of the low-velocity anomalies beneath the rootless Atlas
Mountains: an insight gained from modeling of anisotropy developed by
the travel of Canary Plume
Abstract
When a mantle plume rises from the deep mantle and reaches the base of a
tectonic plate, it changes the traveling direction from vertical to
horizontal. The horizontal spread of plume material is often radially
asymmetric. The plume found below the Canary Hotspot is an example.
Previous studies have suggested that the channeling of the Canary Plume
toward the westernmost Mediterranean (Alboran Sea) may have contributed
to the high elevation of the Moroccan Atlas Mountains while regional
upwelling and edge-driven convection are proposed as other candidates to
explain the topography. Since mantle flow can develop seismic
anisotropy, in this study we incorporate anisotropy as a priori
constraint in teleseismic P-wave tomography. Our improved tomography
result favors the hypothesis that the lateral travel of Canary Plume
material supports the isostatically unstable Moroccan Atlas.