Re: Evidence from Hawaiian volcanoes shows that Earth recycles its crust


"Alan Johnson" <afjohnson@xxxxxxxxxxxxxxxxxx> wrote in message
news:ekonta$q9d$01$1@xxxxxxxxxxxxxxxxxxxx
But surely the location is wrong? If this kind of evidence is turned up
anywhere, it should be close to subduction zones, in back arc settings, or
similar, and not smack-bang in the middle of a plate like Hawaii is? It's
a long way from the nearest source. If I'm being excessively silly, excuse
my ramblings.

Alan,
Contrary to the idea that arc magmas are generated by melting of subducted
slabs, geochemical evidence demands that this is not the case - they are
generated from the mantle wedge above the slab. Unfortunately the
slab-melting model (which went out of favour at least 25 years ago)
is still depicted in the cartoon-style diagrams in most text books.
cheers
Bill


.

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  • Re: Evidence from Hawaiian volcanoes shows that Earth recycles its crust
    ... If this kind of evidence is turned up anywhere, it should be close to subduction zones, in back arc settings, or similar, and not smack-bang in the middle of a plate like Hawaii is? ... excuse my ramblings. ...
    (sci.geo.geology)