Magma generation processes that occur in ocean-ocean subduction zones also occur in ocean-continental margin subduction zones (see Box 2 description). Basalt and rarely andesite magma are produced by 'wet' partial melting at D.
And, as in ocean-ocean subduction zones, heat from the hot rising basalts can
induce partial melting of the overlying continental crust at E, which melts at relatively low temperature to produce rhyolite magma. Some of this rhyolite magma
may blend with later rising basalt to produce andesite magma at E (magma mixing),
or even higher up in a magma chamber in the shallow crust at F.