I don't think the simple presence of rutile exsolution in garnet is
specifically indicative of a particular P-T path.
Rutile exsolution is widely reported in garnet from eclogite facies,
granulite facies, UHT, and I think also occasionally in amphibolite-facies
occurrences.
That said, if anyone knows anything about the diffusion rate controls on
Ti transport leading to rutile needle separation out of garnet, I would love
to know. I have seen some spectacular oscillatory zoning that shows up in
thin section as differing concentrations of exsolved rutile needles in a
garnet from a very rapidly-exhumed eclogite. The same garnet contains
healed fractures in which the rutile needles are gone, and the new clean
garnet contains occasional larger rutile.
Julie Vry
On 9/12/11 7:56 AM, "Shauket Baltybaev" <[log in to unmask]> wrote:
> Hassina and others, thanks a lot!
> Yes, it's most probably rutile, next week I'll check its composition.
> Let me concretize the question - I've never seen such rhomboidal location.
> Is it decompressional structure, lamella or what?
>
> Shauket
>
>
>> Hi Shauket, I could not open the pictures properly, but could that not be
>> Rutile?
>
>> regards
>
>> hassina
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