Abstract
Microprobe analysis provides us new data with in the composition of micas in the metagraywackes of the south Limousin area (French Central Massif). From chlorite zone to sillimanite zone, biotites show an increase in the Al4+ ⇌ Si4+ and Ti4+ ⇌ Mg (Fe)2+ substitution. White micas change from phengitic muscovites with Si4+ from 3,2 to 3,3, to fairly aluminous muscovites, with Si4+ from 3,0 to 3,1 and a hight Na-content (15 to 25 % in paragonite).
Full Text 
Sign-in/Register to access full text options
Sign-in/Register to access full text options 
Paper version not known
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
