Reversed Experiments on Biotite-Quartz-Feldspar Melting in the System Kmash: Implications for Crustal Anatexis

Reversed phase equilibrium constraints on the stability of Mg-Fe-Al biotite

“…( 1) are in good agreement with previous experiments in mixed-volatile ß uids (Bohlen et al 1983) and H 2 O-KCl solutions (Aranovich and Newton 1998), while indicating a reduced stability Þ eld for phlogopite compared to previous data in pure H 2 O (Wood 1976;Peterson and Newton 1989). Aluminum solubility in biotite has been determined in the Fe-, Mg-, and Fe-Mg systems from reversed phase-equilibrium data for the equilibria:…”

“…Keywords: Biotite, phase equilibria, experimental petrology, mixing properties, annite, phlogopite, siderophyllite, eastonite Much of this uncertainty stems from incomplete knowledge of the stability of the most important biotite end-members, phlogopite and annite. In the Mg-system, phase-equilibrium results on the stability Þ eld of phlogopite + quartz relative to enstatite + K-feldspar in pure H 2 O (Wood 1976;Wones and Dodge 1977;Peterson and Newton 1989;Clemens 1995) are compatible with one another. However, all are discordant with experimental results that require a smaller stability Þ eld for phlogopite in mixed H 2 O-CO 2 (Bohlen et al 1983) and H 2 O-KCl (Aranovich and Newton 1998) ß uids.…”

The effect of fluorine and titanium on the vapour-absent melting of phlogopite and quartz

“…But most of the studies using biotite containing pairs for thermometric calculations ignore these constraints. In view of this, the values from such thermometry may represent the lower temperature limits of metamorphism at least in some [Peterson and Newton, 1989] and KMASH-F [Peterson et al, 1991]. Observe the near overlapping of melt compositions in the system KMASH and the present study.…”

“…The solubility of Mg in melt averaged 4.04 by weight percent. Melt analyses from KMASH (Peterson and Newton, 1989) and KMASH-F systems (Peterson et al, 1991) compared on a non-volatile basis to analyses from this study (Fig. 3).…”

Staurolite-bearing gneiss and re-examination of metamorphic zonal mapping of the Higo metamorphic terrane in the Kosa area, central Kyushu, Japan

“…12b); biotite + garnet = orthopyroxene + plagioclase + melt. Obata et al (1994) proposed the following reactions: biotite + quartz = orthopyroxene + K feldspar + liquid according to Peterson and Newton (1989) and Vielzeuf and Clemens (1992) and stated that the dehydration melting reaction may be important and responsible for the large degree of melting as observed in the pervasive occurrence of diatexite because the melt produced by the reaction is nearly equal to the volume % of initial content of biotite (Peterson and Newton, 1989). This reaction is also possible as the orthopyroxene forming reaction in this zone, however, we have no textural evidence for it.…”