Clinopyroxene Solid Solutions and Water in Magmas: Results in the System Phonolitic Tephrite-H2O

D. Dolfi and R. Trigila
Istituto di Mineralogia e Petrografia, Università di Roma, Rome, Italy

Abstract: Clinopyroxene solid solutions crystallized at Ptot = 2 kbar in the natural system phonolitic tephrite-H2O (lava type from Etna eruption 1971) indicate a linear increase of ln Xcatscpx with H2Oliq %. After coupling this with the In Xcatscpx pressure dependence found through experiments, a simple relation has been set up for clinopyroxene- and plagioclase-bearing magmas. This relation allows us to calculate the amount of water dissolved in the melt, at any known pressure in the crustal range.

Mineralogical Magazine; September 1983 v. 47; no. 344; p. 347-351; DOI: 10.1180/minmag.1983.047.344.09
© 1983, The Mineralogical Society
Mineralogical Society (