Dear Colleagues,
A very happy new year to all of you.
I would appreciate if you could share with me any idea/information/reference on the stability conditions of parasite.
I am dealing with some ultra-mafic rocks with olivine, opx, spinel and up to 40% Mg-rich amphibole of parasitic composition. As far as I can see, no sign of any textural reaction
(corona or symplectite) proving that amphiboles are formed at the expenses of any other primary mineral(s) (breakdown reaction).
The minerals (Opx, olivine and parasite) look as they represent a primary "magmatic" assemblage, which recrystallised during the high grade metamorphism (???) (see attached picture).
The preliminary P-T conditions estimated so far using pseudo sections are about 850 - 900C and 10kbar. The same conditions of metamorphism are recorded from associated pelitic granulites. The F-content of
parasite is about 0.05 to 0.20wt.%.
I thank you for sharing with me your experience and knowledge.
Regards,
Hassina
____________________________
Prof Hassina MOURI (PhD Paris 7)
IUGS Councillor 2012- 2016 I www.iugs.org
Department of Geology
University of Johannesburg I www.uj.ac.za
Republic of South Africa
This email and all contents are subject to the following disclaimer:
http://disclaimer.uj.ac.za
