Lithosphere 1, 323–327 (2009)

In some mountains and plateaux, geologists find granite rocks that formed from magmas that had risen up through 'floating' continental tectonic plates. The rocks' origin has often been attributed to melting underneath the continental plates, caused by convection in the hot mantle.

However, Donna Whitney at the University of Minnesota in Minneapolis and her colleagues suggest that subduction — the downward thrusting of one plate under another during tectonic collisions — might be responsible. Using a numerical model, the researchers find that continental subduction can lead to melting of crustal slabs and percolating granitic magma.