On Fri, 26 May 2000 ABdikjse@....... wrote:
> John, I mostly lurk on psn-1 because I'm not an electronics whiz, nor 
> geological expert (ie: nothing to add, but stuff to learn) --- I JUST read 
> something about a Samoan volcano coming to life -- this is allegedly in (or 
> near) the area where the mantle material was found. Maybe that is a clue as 
> to why the emergence of this deep material at this time -- something is 
> happening DEEP and is slowly coming to life?  Just a thought.
> 
> Fascinating group of people here....
> Adrienne

Adrienne,
   The deep rocks found in the region are dated at around 34 million years
old.  Because the tectonic plates are moving fairly fast in the Pacific, this
stuff was injected when this island was far from its current location.  This
is where it would have been under the influence of mantle plumes.  In its
current location however, it is being dotted by volcanos that have a different
origin.  In modern times, most of the activity there is due to arc magmatism.

John Hernlund
E-mail: hernlund@.......
WWW: http://www.public.asu.edu/~hernlund/

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