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Are not sanukite suite rocks simply andesitic boninites? The definition of these rocks is not particularly special even if the minealogy is restricted to Opx + andesine. Rolinator 12:00, 15 October 2006 (UTC)
needs work. edit
Sanukitoids are not really boninitic andesites, though they are similar in some ways.
Boninites are extremely depleted (in incompatible trace element) melts of hydrated mantle in subduction zone. Being refractory, they are high in Ni, Cr, Mg etc.; the high silica comes from enstatite melting. They are very depleted in LREE.
Sanukitoids are more likely slab melts (like adakites) that have reacted with the mantle to get high Ni, Cr. The high LREE/HREE slopes indicate garnet in residue (not seen in boninites) and lack of Eu anomaly means no plag. Probably derived from garnet-amphibole or garnet-pyroxene (ecogite) parent -- bot being metamorphosed ocean crust.
The explanation of sanukitoid origin here is all balled up-- and the irvine barager thing does not apply to these rocks. I will come back and fix this up when i get a chance. Geodoc 05:48, 25 January 2007 (UTC)