Thermodynamic data set for the primitive basalt of Yakedake

by Isoji Miyagi (GSJ)

This database provides thermodynamic calculation results for the primitive basalt magma of Yakedake Volcano. A series of thermodynamic data has been obtained using the Rhyolite-MELTS software on the magma compositions of primitive basalt of Yakedake volcano. The results are visualized as contour diagrams plotted on temperature–pressure planes comprising 23,161 PNG images. These diagrams are interlinked via hypertext, and the associated numerical data are organized in an SQLite3 database, with guidance on extracting relevant information.

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The parameters include the amount and chemical compositions of minerals and melt in equilibrium at some P, T, fO₂, and H₂O concentrations. These parameters were obtained using the Rhyolite-MELTS (v 1.1.0) program (Gualda et al., 2012; Asimow and Ghiorso, 1998; Ghiorso and Sack, 1995) over the range of pressure from 1 atmosphere to 860 MPa with 1-10 MPa step, temperature from 700 to 1400 deg-C with 1 deg-C step, oxygen fugacity FMQ+1 log unit, water concentration 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0; 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, 7.0, 7.2, 7.4, 7.6, 7.8, 8.0 wt.% H₂O, and CO₂ 0.001, 0.01, 0.1, and 1 wt.%. Since the Rhyolite-MELTS program outputs huge quantities of numerical values, I summarized them into a suite of contour maps on a pressure-temperature plane using the GMT program (Wessel and Smith, 1998) and utilized them cross-linked to develop a convenient tool.

In addition, you can extract numerical data from the plot using the sqlite3 command, following the Command Tips on the graph pages.

Starting material of the MELTS computations

No.	SiO₂	TiO₂	Al₂O₃	tFeO	MnO	MgO	CaO	Na₂O	K₂O	P₂O₅	S	Cl	F	Total	what	Comment
6ME3	49.44	1.72	18.52	10.66	0.19	5.70	9.84	2.77	0.81	0.34	0	0	0	100	WR Primitive Enclave	Ishizaki_2007

WR: Whole-rock chemical composition. Pfd: Pyroclastic flow deposit.

An example of citation:

Miyagi (2025) Thermodynamic data set for the primitive basalt of Yakedake. https://doi.org/10.57765/2003425

References:

Asimow, P., Ghiorso, M. (1998) Algorithmic modifications extending melts to calculate subsolidus phase relations. American Mineralogist 83, 1127–1131. https://doi.org/10.2138/am-1998-9-1022
Ghiorso, M. S. and Sack, R. O. (1995) Chemical mass transfer in magmatic processes iv. a revised and internally consistent thermodynamic model for the interpolation and extrapolation of liquid-solid equilibria in magmatic systems at elevated temperatures and pressures. Contributions to Mineralogy and Petrology 119, 197–212. https://doi.org/10.1007/BF00307281
Gualda, G. A. R., Ghiorso, M. S., Lemons, R. V., and Carley, T. L. (2012) Rhyolite-MELTS: a Modified Calibration of MELTS Optimized for Silica-rich, Fluid-bearing Magmatic Systems. J. Petrol., 53(5):875–890. https://doi.org/10.1093/petrology/egr080
Ishizaki, Y. (2007) Dacite-basalt magma interaction at Yakedake volcano, central Japan: petrographic and chemical evidence from the 2300 years B.P. Nakao pyroclastic flow deposit. Journal of Mineralogical and Petrological Sciences, 102, no. 3, 194-210. https://doi.org/10.2465/jmps.060619
Wessel, P. and Smith, W. (1998) New, improved version of generic mapping tools released. EOS Trans. Amer. Geophys. U. 79 (47), 579. https://doi.org/10.1029/98EO00426

Version history:

January 2026: Initial release

If you have questions about this page, contact Isoji MIYAGI