Geodynamic-tectonic model of the Variscan bel exposed in the French Massif Central. A. Silurian (c. 420 Ma) subduction of the Medio-European Ocean. B. Middle Devonian (c. 385 Ma) subduction and partial melting of the hyper-extended northern continental margin of the Gondwana craton. C. Late Devonian (c. 365 Ma) slab retreat, opening of the Brévenne rift and syn-orogenic exhumation of high-grade partially molten nappes. D. Lower Carboniferous (c. 330 Ma) development of an orogenic plateau by lateral flow of partially molten orogenic root in a context of plate convergence and southward slab retreat. E. Late Carboniferous (c. 300 Ma) gravitational collapse of the Variscan belt in a context of southward slab delamination accommodated by lateral and upward flow of the partially molten orogenic root concomitant with brittle extension of the upper crust.