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alphaMELTS 1.9 is available at the download and information site.
alphaMELTS 2 standalone & for MATLAB/Python are available on request
(see the Version 2 tab on the download site for more details).
For news of all MELTS software see the MELTS Facebook page.

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#91
"Output: both" is for alphaMELTS 2 and alphaMELTS for MATLAB/Python only.

If you're on alphaMELTS 1.9 then have a look at menu option 14 - "Write thermodynamic output for all phases".
#92
Hi Paul,
when I add a line, "Output: both" in the morb.melts file for example, Alphamelts always shown "Error during input file read, offending record: 'output: bot' ", when Alphamelts reading the melts file. Thanks in advance.
#93
Unfortunately, calculating the activity of some oxides is not really a well-defined exercise.

For SiO2, TiO2, Al2O3, Fe2O3, CO2, and H2O, these oxides are also components of the MELTS, pMELTS, and rMELTS liquid models and their activities are given in melts-liquid.tbl (you may have to set "output: both" in your .melts file to enable MELTS GUI style output files so that you get melts-liquid.tbl). However, to turn these into activity coefficients you have to decide what mole fraction to use, since gamma = activity/(mole fraction). The mole fraction of, for example, SiO2 molecules among the molecules that represent the liquid in MELTS is *not* the same as the mole fraction of SiO2 on an oxide basis. Probably what you want, though, is activity coefficient relative to an ideal mixture of oxides, in which case go ahead and convert the weight % oxides into mole fractions of oxides (this is not done for you), and divide the activity of SiO2 given in melts-liquid.tbl by mole fraction to get activity coefficient.

The reason this is straightforward for those six oxides is that activity is defined by the relation mu(P,T,X) = mu0(P,T) + R T ln a and for these six (only), we know both mu and mu0 (the chemical potential of the pure liquid oxide at the P and T of interest).

For the other oxides (Cr2O3, FeO, MnO, MgO, CoO, NiO, CaO, Na2O, K2O, P2O5), the liquid model represents these as non-oxide mineral-like molecules (MgCr2O4, Fe2SiO4, MnSi0.5O2, Mg2SiO4, CoSi0.5O2, NiSi0.5O2, CaSiO3, Na2SiO4, KAlSiO4, Ca3(PO4)2) and we only have mu and mu0 for these molecules, not for the oxides. It is straightforward to compute mu for the oxides because the liquid is in equilibrium and so, for example, mu(CaO) + mu(SiO2) = mu(CaSiO3). But the same statement is not true for the end members: mu0(CaO) + mu0(SiO2) ≠ mu0(CaSiO3), because pure CaO, SiO2, and CaSiO3 liquids are NOT in equilibrium with each other. That means MELTS *does not know* the standard state chemical potential of CaO and therefore cannot convert the chemical potential of CaO into activity of CaO.

My advice is try to be satisfied with, for example, activity and activity coefficient of CaSiO3 and figure out how to avoid needing activity coefficient of CaO. If you really want this you have to introduce an external (probably not MELTS-compatible) function for standard state chemical potential of pure CaO liquid.

OK, that was pretty heavy. If you need further explanation please ask.

We do our best job of this calculation in the MATLAB and python versions of melts, rather than in alphaMELTS proper.
#94
I can't find the activity of oxide of a mafic silicate melt (except aH2O) in any output_file, when using Alphamelts. Please show us how to calculate them. Thanks in advance!
#95
General usage / Re: Re: Re: Re: [FAQ] THE QUAD...
Last post by Ri Cao - August 01, 2022, 12:49:15 PM
Dear Paula,
Great, thanks for the clarification.

I also got some replies from the conference organizer as well. Sorry for missing the Goldsmith workshop since I was ill at that time period.

Hopefully and definitely, I will be able to attend the next MELTS conference in Newzeland. Please keep me in the loop if there is anything new that comes through. Thank you very much.

Best regards,
Ri Cao
#96
General usage / Re: Re: Re: Re: [FAQ] THE QUAD...
Last post by Paula - July 29, 2022, 08:53:30 AM
Hi Ri,

I'm not sure. They haven't updated the website fully. I guess you can add the workshop when registering for the conference, but I haven't tried yet. To be honest, I'm still tying up loose ends from the recent workshop at Goldschmidt!

The full price is supposed to be 160 NZD. Students and early-career researchers (as defined here) should get a reduced rate of 60 NZD. I will follow up next week to see how you get that rate.

Best wishes,
Paula
#97
News and updates / Re: Comma Problem
Last post by Paula - July 29, 2022, 08:23:50 AM
Hi Antoine,

Ah, sorry that didn't work. You could try easyMelts. It can do everything that the old GUI can. I don't know if it will get around the comma problem but it would be interesting to see:

https://magmasource.caltech.edu/gitlist/easyMelts.git/

Paula
#98
General usage / Re: Re: Re: Re: [FAQ] THE QUAD...
Last post by Ri Cao - July 29, 2022, 08:16:44 AM
Dear Paula,
Sorry for my interruption again and hope you are doing well.

I just realized that there is another MELTS workshop for the IAVCEI conference in New Zealand, early next year. I was wondering how shall I sign up for this workshop? Are there any links for registration and how much will that cost? Thank you very much and I look forward to your response.

Sincerely,
Ri Cao
#99
News and updates / Re: Comma Problem
Last post by Antoine.fr - July 29, 2022, 08:13:02 AM
Hello Paula,

Thank you for your answer!
Yes I have read Jose's post before. Lucky him, the trick didn't work from me!
I have tried to install MELTS on linux and it does the same thing...
Thanks anyway,

Best regards,
Antoine.
#100
News and updates / Re: Melts Calculations Slowing...
Last post by aprajitmahajan - July 26, 2022, 05:31:35 PM
Dear Paula,
That worked, thank you!!


Best wishes,
Aprajit.