Can any member of our group provide an explanation as to why
amphibole in a metamorphic rock (or, for that matter kyanite, or any
other normally straight elongate mineral) might instead grow as
randomly-oriented curved crystals? (Some of the amphibole curves so
much that groups of crystals forms circles or perhaps spirals in a
thin-section view).
This does not look to me to be a product of
growth-during-deformation. The overall distribution of the amphibole
crystals is random, although that texture has been overprinted a
little by the development of a later foliation.
I have a vague vague recollection that this texture might be related
to the speed of mineral growth(?), but I haven't been able to turn up
a reference.
Thanks in advance,
Julie Vry
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Julie Vry
Senior Lecturer - metamorphic petrology
School of Earth Sciences
Victoria University of Wellington
P.O. Box 600
Wellington, New Zealand
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