Table A2.

Summary of selected thermodynamic solutions of solid-liquid equilibria for ultracalcic melt inclusions in olivines of the pumices erupted during paroxysmal events. See text and Figure 6 for details. The melt composition is the average Ca-rich melt inclusions in Table 1; olivine and clinopyroxene analyses n. 4 and n. 13 in Table 2

Reaction (1): Fo (sol)+SiO2=CEnHydrous melt with H2O=3 wt%
T (°C)aFOaCEnGraphic(kJ)log aSiO2P (MPa)
10000.81840.5336−6.2297−0.5087218
11000.81520.4654−5.0144−0.5119274
11250.81440.4512−4.6908−0.5127291
11500.81370.4378−4.3595−0.5134310
11750.81300.4253−4.0207−0.5141329
12000.81230.4136−3.6743−0.5147349
12500.81110.3922−2.9592−0.5160394
ReferenceSack & Ghiorso (1989)Gasparik (1990)Ghiorso & Sack (1995)
Reaction (2): Di=1/2SiO2(liq)+1/2Ol(liq)+Wo(liq)Hydrous melt with H2O=3 wt%
P (MPa)aDiaWo (liq)aFo (liq)Graphic(kJ)log aSiO2T (°C)
−0.512911190.13140.050245.6083
1000.84840.13180.050444.9349−0.51341135
2000.84820.13230.050544.1970−0.51391152
3000.84810.13270.050743.4706−0.51431169
4000.84800.13320.050842.7564−0.51481185
6000.84780.13390.051141.3662−0.51561215
8000.84760.13460.051340.0289−0.51631243
ReferenceGasparik (1990)Sack & Ghiorso (1989)Sack & Ghiorso (1989)Ghiorso & Sack (1995)