Shallow mantle flow drives Yellowstone magma, challenging deep-plume idea
A new three-dimensional geodynamic model of western North America shows Yellowstone is fed by shallow asthenospheric mantle transported eastward by a long-lived 'mantle wind' rather than a deep mantle plume. This flow creates decompression melting and distributes magma as a thick mush across the lithosphere, forming a southwest-dipping channel that acts as a conduit for magma over long timescales. The findings align with geophysical observations and offer a unified explanation for how large magmatic systems beneath supervolcanoes can persist without persistent liquid magma chambers.