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Supposing that it is the business of section officers to stir the pot from time to time, I have elected to introduce myself (as President-Elect of the Volcanology, Geochemistry, and Petrology section) by way of this small polemic on a matter of general interest, the origin of mafic magma. My hope is to identify a piece of folly so that it will go away. Knowing, however, the Gresham-Murphy law of information that bad ideas outrun the good, my expectations are somewhat lower than my hopes.

In a recent abstract about the perturbed geochemistry of mafic crustal rocks, the usual options were invoked: enriched mantle source, crustal contamination of basaltic magma, and, in addition, “ … by partial melting of basaltic crust in the lower crust or uppermost mantle.” This last hypothesis appears with some frequency in the literature. Accordingly, I refrain from pointing the finger at the amiably misguided perpetrators by citing references to any of them.