Ferro- and magnesiocarpholite in the “Bündnerschiefer” of the eastern Central Alps (Grisons and Engadine window).
Goffé, Bruno; Oberhänsli, Roland
European Journal of Mineralogy Volume 4 Number 4 (1992), p. 835 - 838
published: Aug 11, 1992
manuscript accepted: Mar 25, 1992
manuscript received: Feb 7, 1992
ArtNo. ESP147050404011, Price: 29.00 €
Abstract Ferro- and magnesiocarpholite are described for the first time in metapelites of the “Bundnerschiefer” nappes of the eastern Central Alps. (Fe,Mg)-carpholite compositions range from Mg/(Fe+Mn+Mg) = 0.36 to 0.70, with up to 4.6 wt% F. Minimum pressure estimates range from 8 to 6 kbar for early fluorine-poor carpholite and late fluorine-rich carpholite, respectively. Parageneses of carpholite and chloritoid indicate temperatures around 350°C in Lugnez valley. These first findings of carpholite demonstrate an early HP-LT evolution in an area so far considered to lack significant HP metamorphism. This implies that HP terranes extend continuously from the Western Alps, through the Central Alps, to the Engadine and Tauern Window.