There are three ways to use the MELTS (or pMELTS) software package:

• ENKI Portal server: The future of MELTS. For tutorials and introductory information, visit the ENKI Portal YouTube channel.
• Standalone: If you use a UNIX-based computer (e.g., a system running Linux or Mac OS X), download a standalone version that generates results on your own computer. Go to the UNIX page or Mac OS X page.
  
• alphaMELTS: Paul Asimow and Paula Antoshechkina have created a scripted version of MELTS that runs on UNIX systems (including Mac OS X and Linux) and machines running Windows. alphaMELTS includes the ability to model water solubility in mantle minerals and the effect of water on the mantle solidus. For more information and instructions, see the CalTech alphaMELTS web site.
  

There are two ways to use the rhyolite-MELTS software package:

• Standalone: If you use Mac OS 10.8+, you may download a standalone version of the executable program. Go to MELTS for Mac OS X page for instructions. Ubuntu-based UNIX versions of rhyolite-MELTS may be downloaded from the UNIX MELTS page.
• MELTS for Excel on Windows: If you have access to Excel 2010 or 2013 running on a Windows platform, you can download a macro-enabled Excel workbook that serves as a front end graphical user interface to a server at OFM Research that runs MELTS web services. Go to MELTS for Excel for instructions.

For help with the standalone MELTS/pMELTS, see MELTS Manual.

Please visit the ENKI Portal server, and take a look at the MELTSmodel class in the ThermoEngine Python package.

The following figure illustrates future plans for extending MELTS to a broader range of temperature and pressure conditions.

xMELTS is the code name for a project involving Ghiorso (at OFM Research Inc.), Marc Hirschmann (at the University of Minnesota) and Tim Grove (at M.I.T). The aim is to create an entirely new liquid model that incorporates recently completed work on the liquid equation of state (American Journal of Science, v 304, no 8-9, 2004) and an associated solution formalism that together should facilitate modeling liquid properties from 0.0001 to 40 GPa and 500° to 3000°C. The intended use of xMELTS is as a replacement for MELTS and pMELTS that will extend modeling capabilities to the top of the Earth's lower mantle. One aspect of the xMELTS project is the generation of a comprehensive, up-to-date database of liquid-solid experimental phase equilibrium data. This database is called LEPR, which stands for Library of Experimental Phase Relations, and is accessible at lepr.ofm-research.org.

The release of xMELTS is pending while solution models are under development for high-pressure garnets and pyroxenes. This work is being undertaken jointly with researchers at CalTech.

The mdMELTS project is a far reaching vision of extending MELTS modeling capabilities down to the base of the Earth's lower mantle. While the "x" in xMELTS stands for extreme, the "md" in mdMELTS stands for molecular dynamics (MD). This project is being undertaken by Ghiorso (at OFM Research Inc.) and Frank Spera (at UC Santa Barbara) and is as yet unfunded. The idea is to extend the silicate liquid equation of state calibration to very high pressure (and temperature) utilizing MD computer simulations of liquids. This will allow liquid-solid phase equilibria to be modeled at high pressure. Our preliminary work on this project is focusing on the system MgO-SiO2. As results and models become available, they will be posted to this web site.

Unlike Athena, MELTS,89/= rhyolite-MELTS and pMELTS did not suddenly emerge — fully formed — from the forehead of Zeus. When you use results from MELTS, rhyolite-MELTS or pMELTS in a publication, abstract or talk, please cite the appropriate reference(s).

Calculations derived from MELTS should be cited as:

Ghiorso, Mark S., and Sack, Richard 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

Asimow PD, Ghiorso MS (1998) Algorithmic Modifications Extending MELTS to Calculate Subsolidus Phase Relations. American Mineralogist 83, 1127-1131

Calculations derived from pMELTS should be cited as:

Ghiorso, Mark S., Hirschmann, Marc M., Reiners, Peter W., and Kress, Victor C. III (2002) The pMELTS: An revision of MELTS aimed at improving calculation of phase relations and major element partitioning involved in partial melting of the mantle at pressures up to 3 GPa. Geochemistry, Geophysics, Geosystems 3(5), 10.1029/2001GC000217

Calculations derived from rhyolite-MELTS should be cited as:

Gualda G.A.R., Ghiorso M.S., Lemons R.V., Carley T.L. (2012) Rhyolite-MELTS: A modified calibration of MELTS optimized for silica-rich, fluid-bearing magmatic systems. Journal of Petrology, 53, 875-890.

Ghiorso M.S., Gualda, G.A.R., (2015) An H₂O-CO₂ mixed fluid saturation model compatible with rhyolite-MELTS. Contributions to Mineralogy and Petrology 2015, in press