Can slab melting be caused by flat subduction

  title={Can slab melting be caused by flat subduction},
  author={Marcus Gutscher and Ren{\'e} Charles Maury and Jean-Philippe Eissen and Erwan Bourdon},
Slab melting has been suggested as a likely source of adakitic arc magmas (i.e., andesitic and dacitic magmas strongly depleted in Y and heavy rare earth elements). Existing numerical and petrologic models, however, restrict partial melting to very young (≤ 5 Ma) oceanic crust (typically at 60–80 km depth). Paradoxically, most of the known Pliocene-Quaternary adakite occurrences are related to subduction of 10–45 Ma lithosphere, which should not be able to melt under normal subduction-zone… 

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