Slab Rollback & Back-Arc Basin Opening

This simulation isolates one specific, well-defined mechanic of subduction-zone dynamics: how the negative thermal buoyancy of an aging, sinking oceanic slab drives the trench itself to migrate through the mantle — trench rollback — and how that rollback competes against the motion of the overriding plate to either stretch open a new back-arc basin or compress the margin into mountains. Adjust the subducting plate's age (which sets its thickness and density via a real thermal-boundary-layer relation), the convergence rate, the overriding plate's own motion, and the asthenosphere's viscosity, and watch the slab dip, trench position, and back-arc seafloor respond in real time, with the governing slab-pull, rollback-velocity, and spreading-rate formulas computed live in the readouts.