The return of stagnant slab recorded by intraplate volcanism.

Subducted plates often stagnate in the mantle transition zone (MTZ), and the fate of the stagnant slabs is still debatable. They may sink into the lower mantle, or remain partially trapped in the MTZ, but it is uncertain whether they can return to the upper mantle. We report geochemical evidence of late-Miocene (~6 Ma) basalts from, and upper mantle seismic evidence beneath Shuangyashan, an area above the slab tear of the stagnant Pacific plate in eastern Asia, to show how the slab returns to the upper mantle from the MTZ.