Yellowstone is widely recognized for its crustal magma reservoirs replenished by asthenospheric melts. However, how primary melts traverse the rigid lithosphere and evolve into bimodal volcanism remains unclear. By leveraging multidisciplinary observations and a data-oriented geodynamic modeling approach, we demonstrate that magma generation and migration in the Yellowstone region are primarily governed by lithospheric tectonics, with negligible contribution from the mantle plume. Below Yellowstone, our model predicts a southwest-dipping extension zone, shaped jointly by the lithospheric body force and basal traction. This tilted translithospheric deforming zone resembles the geophysically imaged magma plumbing system, confirming the key role of tectonic extension in tapping asthenospheric melts to shallow depths. Furthermore, we suggest that the translithospheric magma plumbing system facilitates complex magmatic processes, ultimately driving surface bimodal volcanism.
Cao et al. (Thu,) studied this question.