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News:
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Recent posts
#1
The MELTS family of algorithms, and scientific discussion / Re: how to suppress mineral in...
Last post by Paula - July 02, 2025, 06:03:42 PMHi Kai,
To suppress a phase you add a .melts file-like line in the Settings. Something like:
The Find Wet Liquidus result differs slightly because it performs one or more equilibration calculations as part of the algorithm, whereas the original Find Liquidus routine only uses affinities. In this case, the temperatures agree to within 0.2 oC because the system is not water-saturated.
The MATLAB and Python versions always use Find Wet Liquidus. The app has both options for backwards compatibility and so it can be more easily compared to other software, such as easyMelts.
Paula
To suppress a phase you add a .melts file-like line in the Settings. Something like:
Code Select
ptpath.engine.setSystemProperties(["Suppress: olivine"])The Find Wet Liquidus result differs slightly because it performs one or more equilibration calculations as part of the algorithm, whereas the original Find Liquidus routine only uses affinities. In this case, the temperatures agree to within 0.2 oC because the system is not water-saturated.
The MATLAB and Python versions always use Find Wet Liquidus. The app has both options for backwards compatibility and so it can be more easily compared to other software, such as easyMelts.
Paula
#2
General usage / Re: MELTS_Excel
Last post by Paula - July 02, 2025, 05:49:01 PMThe last five columns are the molar proportions of the end members in the order listed in the header i.e:
https://magmasource.caltech.edu/forum/index.php/topic,143.0.html
There is a mistake in the header for the oxides, though. It lists all the MELTS system oxides, in the standard MELTS order. However, values are only printed for oxides in the spinel solid solution, so the header should read:
The spinel calculator mentioned in the thread is still there (https://magmasource.caltech.edu/calculator/spinel.php). The ordering calculation no longer works. But if you select "Assume inverse ordering within range of configurational freedom e.g. [4]B[6](A,B)2O4" (which is a good approximation for magnetite-rich compositions) you can verify that the values in your output can be converted from oxide wt% to end-member molar proportions and vice versa.
Paula
Quotechromite hercynite magnetite spinel ulvospinelIf you are confused why the molar proportion of hercynite is negative then see this thread:
https://magmasource.caltech.edu/forum/index.php/topic,143.0.html
There is a mistake in the header for the oxides, though. It lists all the MELTS system oxides, in the standard MELTS order. However, values are only printed for oxides in the spinel solid solution, so the header should read:
QuoteTiO2 (wt%) Al2O3 (wt%) Fe2O3 (wt%) Cr2O3 (wt%) FeO (wt%) MgO (wt%)
The spinel calculator mentioned in the thread is still there (https://magmasource.caltech.edu/calculator/spinel.php). The ordering calculation no longer works. But if you select "Assume inverse ordering within range of configurational freedom e.g. [4]B[6](A,B)2O4" (which is a good approximation for magnetite-rich compositions) you can verify that the values in your output can be converted from oxide wt% to end-member molar proportions and vice versa.
Paula
#3
General usage / Re: MELTS_Excel
Last post by Renqiang Liao - June 30, 2025, 11:44:12 PMDear Paula,
The following data is a portion of spinel that I have intercepted from the modeling results. How should I know the percentage of magnetite and the corresponding chemical composition from this data.
If it is convenient, you can copy and paste it into an excel sheet for better visualization.
I would be very grateful if you could help.
Thanks for your time.
Renqiang
Index T (C) P (MPa) deltaQFM mass (g) rho (g/cm3) G (kJ) H (kJ) S (J/K) Cp (J/K) V (cm3) alpha (1/K) beta (1/bar) d2V/dT2 d2V/dP2 d2V/dTdP SiO2 (wt%) TiO2 (wt%) Al2O3 (wt%) Fe2O3 (wt%) Cr2O3 (wt%) FeO (wt%) MnO (wt%) MgO (wt%) NiO (wt%) CoO (wt%) CaO (wt%) Na2O (wt%) K2O (wt%) P2O5 (wt%) H2O (wt%) CO2 (wt%) SO3 (wt%) Cl2O-1 (wt%) F2O -1 (wt%) chromite hercynite magnetite spinel ulvospinel
6 1105 200 -5.150465347 0.231471602 4.640479356 -1.945716914 -1.277172938 0.485102475 0.218354804 0.049880968 4.9189E-05 5.15401E-07 1.07E-09 1.18E-13 0 5.72131326 7.262995515 52.41379176 28.99671017 5.605189297 0 -0.144013252 0.69676763 0.295232331 0.152013291
7 1100 200 -5.272024288 0.660819925 4.647505403 -5.537215919 -3.638827329 1.382506346 0.62238235 0.142188092 4.84386E-05 5.08028E-07 3.00E-09 3.34E-13 0 6.101202423 7.094900379 51.79323501 29.56289271 5.44776948 0 -0.139452471 0.689660091 0.287416716 0.162375663
8 1095 200 -5.386580892 1.089486164 4.657384135 -9.08110738 -5.969567205 2.2742683 1.023861994 0.233926628 4.775E-05 5.00868E-07 4.89E-09 5.46E-13 0 6.45611602 6.83528349 51.30338074 30.1613798 5.24383995 0 -0.134442707 0.684843634 0.277348684 0.172250389
9 1090 200 -5.49784227 1.483105541 4.666205255 -12.30408963 -8.09286605 3.089332485 1.391014944 0.317839756 4.70828E-05 4.94047E-07 6.57E-09 7.36E-13 0 6.799090722 6.603662114 50.81504373 30.72119391 5.061009519 0 -0.129902438 0.679827743 0.268271772 0.181802924
10 1085 200 -5.60500363 1.846573858 4.674443587 -15.25158567 -10.03859442 3.838303018 1.728694187 0.395036077 4.64446E-05 4.87578E-07 8.08E-09 9.08E-13 0 7.126026765 6.386823246 50.34716959 31.24904249 4.890937914 0 -0.125689911 0.674959337 0.259792101 0.190938473
11 1080 200 -5.707862988 2.181721318 4.682162581 -17.94371559 -11.82017522 4.525396573 2.038867231 0.465964451 4.58369E-05 4.81467E-07 9.44E-09 1.06E-12 0 7.435494404 6.183746821 49.90305023 31.74531895 4.732389603 0 -0.121766729 0.670296288 0.251855511 0.19961493
12 1075 200 -5.806299105 2.490420898 4.689419053 -20.40001202 -13.45047297 5.154870784 2.323498451 0.531072372 4.52605E-05 4.75718E-07 1.07E-08 1.20E-12 0 7.726688972 5.993428681 49.48482547 32.21079248 4.584264394 0 -0.118100376 0.665879867 0.244413248 0.207807261
13 1070 200 -5.900259468 2.774547481 4.696263308 -22.63926775 -14.9417482 5.73094557 2.584517418 0.590798961 4.47155E-05 4.70325E-07 1.17E-08 1.33E-12 0 7.999334814 5.814891064 49.0936505 32.64653659 4.44558703 0 -0.114663626 0.661736924 0.237421696 0.215505006
14 1065 200 -5.989747362 3.035942436 4.702739516 -24.67939356 -16.30560615 6.257734491 2.82379151 0.645568913 4.42014E-05 4.65279E-07 1.27E-08 1.44E-12 0 8.253579283 5.647194345 48.72988008 33.05385129 4.315494996 0 -0.11143379 0.657882361 0.230841964 0.222709465
15 1060 200 -6.074809387 3.276385265 4.708886234 -26.53730421 -17.55295321 6.739189893 3.043104345 0.69578773 4.37173E-05 4.60568E-07 1.36E-08 1.55E-12 0 8.489889645 5.489447225 48.39324864 33.43418879 4.193225705 0 -0.108391944 0.654321596 0.224639415 0.229430932
16 1055 200 -6.155524322 3.497572699 4.714737023 -28.22884057 -18.69396821 7.17906288 3.244140478 0.741838343 4.3262E-05 4.56177E-07 1.44E-08 1.64E-12 0 8.708960801 5.340814135 48.08303288 33.78908822 4.078103966 0 -0.105522204 0.651052829 0.218783172 0.235686203
17 1050 200 -6.231993704 3.701104755 4.720321069 -29.76872895 -19.73809115 7.580877306 3.428475964 0.784079028 4.2834E-05 4.52089E-07 1.51E-08 1.73E-12 0 8.91163761 5.200519572 47.79819036 34.12012214 3.969530318 0 -0.102811093 0.648068999 0.21324564 0.241496454
18 1045 200 -6.304334249 3.888476742 4.725663786 -31.17057357 -20.69402831 7.947915832 3.59757393 0.822842445 4.24318E-05 4.48287E-07 1.58E-08 1.80E-12 0 9.098852637 5.067849689 47.53747208 34.42885503 3.866970562 0 -0.100247006 0.645359401 0.208002075 0.24688553
19 1040 200 -6.372671956 4.061076067 4.730787363 -32.44687616 -21.56977149 8.283215687 3.752784145 0.858435553 4.20539E-05 4.44754E-07 1.64E-08 1.88E-12 0 9.271578336 4.942151694 47.29951056 34.71681281 3.769946603 0 -0.097819792 0.642910973 0.203030196 0.251878623
20 1035 200 -6.437137694 4.220182636 4.735711256 -33.60907599 -22.37262773 8.589571729 3.895345538 0.891140192 4.16986E-05 4.41472E-07 1.69E-08 1.94E-12 0 9.430791759 4.82283163 47.0828863 34.98546171 3.678028603 0 -0.095520418 0.640709285 0.19830985 0.256501283
The following data is a portion of spinel that I have intercepted from the modeling results. How should I know the percentage of magnetite and the corresponding chemical composition from this data.
If it is convenient, you can copy and paste it into an excel sheet for better visualization.
I would be very grateful if you could help.
Thanks for your time.
Renqiang
Index T (C) P (MPa) deltaQFM mass (g) rho (g/cm3) G (kJ) H (kJ) S (J/K) Cp (J/K) V (cm3) alpha (1/K) beta (1/bar) d2V/dT2 d2V/dP2 d2V/dTdP SiO2 (wt%) TiO2 (wt%) Al2O3 (wt%) Fe2O3 (wt%) Cr2O3 (wt%) FeO (wt%) MnO (wt%) MgO (wt%) NiO (wt%) CoO (wt%) CaO (wt%) Na2O (wt%) K2O (wt%) P2O5 (wt%) H2O (wt%) CO2 (wt%) SO3 (wt%) Cl2O-1 (wt%) F2O -1 (wt%) chromite hercynite magnetite spinel ulvospinel
6 1105 200 -5.150465347 0.231471602 4.640479356 -1.945716914 -1.277172938 0.485102475 0.218354804 0.049880968 4.9189E-05 5.15401E-07 1.07E-09 1.18E-13 0 5.72131326 7.262995515 52.41379176 28.99671017 5.605189297 0 -0.144013252 0.69676763 0.295232331 0.152013291
7 1100 200 -5.272024288 0.660819925 4.647505403 -5.537215919 -3.638827329 1.382506346 0.62238235 0.142188092 4.84386E-05 5.08028E-07 3.00E-09 3.34E-13 0 6.101202423 7.094900379 51.79323501 29.56289271 5.44776948 0 -0.139452471 0.689660091 0.287416716 0.162375663
8 1095 200 -5.386580892 1.089486164 4.657384135 -9.08110738 -5.969567205 2.2742683 1.023861994 0.233926628 4.775E-05 5.00868E-07 4.89E-09 5.46E-13 0 6.45611602 6.83528349 51.30338074 30.1613798 5.24383995 0 -0.134442707 0.684843634 0.277348684 0.172250389
9 1090 200 -5.49784227 1.483105541 4.666205255 -12.30408963 -8.09286605 3.089332485 1.391014944 0.317839756 4.70828E-05 4.94047E-07 6.57E-09 7.36E-13 0 6.799090722 6.603662114 50.81504373 30.72119391 5.061009519 0 -0.129902438 0.679827743 0.268271772 0.181802924
10 1085 200 -5.60500363 1.846573858 4.674443587 -15.25158567 -10.03859442 3.838303018 1.728694187 0.395036077 4.64446E-05 4.87578E-07 8.08E-09 9.08E-13 0 7.126026765 6.386823246 50.34716959 31.24904249 4.890937914 0 -0.125689911 0.674959337 0.259792101 0.190938473
11 1080 200 -5.707862988 2.181721318 4.682162581 -17.94371559 -11.82017522 4.525396573 2.038867231 0.465964451 4.58369E-05 4.81467E-07 9.44E-09 1.06E-12 0 7.435494404 6.183746821 49.90305023 31.74531895 4.732389603 0 -0.121766729 0.670296288 0.251855511 0.19961493
12 1075 200 -5.806299105 2.490420898 4.689419053 -20.40001202 -13.45047297 5.154870784 2.323498451 0.531072372 4.52605E-05 4.75718E-07 1.07E-08 1.20E-12 0 7.726688972 5.993428681 49.48482547 32.21079248 4.584264394 0 -0.118100376 0.665879867 0.244413248 0.207807261
13 1070 200 -5.900259468 2.774547481 4.696263308 -22.63926775 -14.9417482 5.73094557 2.584517418 0.590798961 4.47155E-05 4.70325E-07 1.17E-08 1.33E-12 0 7.999334814 5.814891064 49.0936505 32.64653659 4.44558703 0 -0.114663626 0.661736924 0.237421696 0.215505006
14 1065 200 -5.989747362 3.035942436 4.702739516 -24.67939356 -16.30560615 6.257734491 2.82379151 0.645568913 4.42014E-05 4.65279E-07 1.27E-08 1.44E-12 0 8.253579283 5.647194345 48.72988008 33.05385129 4.315494996 0 -0.11143379 0.657882361 0.230841964 0.222709465
15 1060 200 -6.074809387 3.276385265 4.708886234 -26.53730421 -17.55295321 6.739189893 3.043104345 0.69578773 4.37173E-05 4.60568E-07 1.36E-08 1.55E-12 0 8.489889645 5.489447225 48.39324864 33.43418879 4.193225705 0 -0.108391944 0.654321596 0.224639415 0.229430932
16 1055 200 -6.155524322 3.497572699 4.714737023 -28.22884057 -18.69396821 7.17906288 3.244140478 0.741838343 4.3262E-05 4.56177E-07 1.44E-08 1.64E-12 0 8.708960801 5.340814135 48.08303288 33.78908822 4.078103966 0 -0.105522204 0.651052829 0.218783172 0.235686203
17 1050 200 -6.231993704 3.701104755 4.720321069 -29.76872895 -19.73809115 7.580877306 3.428475964 0.784079028 4.2834E-05 4.52089E-07 1.51E-08 1.73E-12 0 8.91163761 5.200519572 47.79819036 34.12012214 3.969530318 0 -0.102811093 0.648068999 0.21324564 0.241496454
18 1045 200 -6.304334249 3.888476742 4.725663786 -31.17057357 -20.69402831 7.947915832 3.59757393 0.822842445 4.24318E-05 4.48287E-07 1.58E-08 1.80E-12 0 9.098852637 5.067849689 47.53747208 34.42885503 3.866970562 0 -0.100247006 0.645359401 0.208002075 0.24688553
19 1040 200 -6.372671956 4.061076067 4.730787363 -32.44687616 -21.56977149 8.283215687 3.752784145 0.858435553 4.20539E-05 4.44754E-07 1.64E-08 1.88E-12 0 9.271578336 4.942151694 47.29951056 34.71681281 3.769946603 0 -0.097819792 0.642910973 0.203030196 0.251878623
20 1035 200 -6.437137694 4.220182636 4.735711256 -33.60907599 -22.37262773 8.589571729 3.895345538 0.891140192 4.16986E-05 4.41472E-07 1.69E-08 1.94E-12 0 9.430791759 4.82283163 47.0828863 34.98546171 3.678028603 0 -0.095520418 0.640709285 0.19830985 0.256501283
#4
General usage / Re: MELTS_Excel
Last post by Renqiang Liao - June 25, 2025, 12:27:41 AMDear Paula,
I need your help with a computational detail. I used MELTS_Excel to simulate the process of how basaltic magma changes into different minerals, and the results show magnetite in the crystalline mineral phase. However, the simulation classifies magnetite as spinel, which contains chromite, hercynite, magnetite, spinel, and ulvospinel. I understand that magnetite and spinel have similar crystal structures, which is why this happens. But how do I know the percentage of magnetite and its chemical compositions from the spinel results? I'm sorry, but I don't know how to upload a picture to express my confusion more clearly.
Thanks for your time!
Renqiang
I need your help with a computational detail. I used MELTS_Excel to simulate the process of how basaltic magma changes into different minerals, and the results show magnetite in the crystalline mineral phase. However, the simulation classifies magnetite as spinel, which contains chromite, hercynite, magnetite, spinel, and ulvospinel. I understand that magnetite and spinel have similar crystal structures, which is why this happens. But how do I know the percentage of magnetite and its chemical compositions from the spinel results? I'm sorry, but I don't know how to upload a picture to express my confusion more clearly.
Thanks for your time!
Renqiang
#5
The MELTS family of algorithms, and scientific discussion / Re: how to suppress mineral in...
Last post by Kai Wen - June 24, 2025, 07:05:12 AMMoreover, sorry, in the app, it seems to adjust my content automatically, if I choose find wet liquids
find wet liquids
Initial alphaMELTS calculation at: P 4000.000000 (bars), T 1113.085938 (C)
liquid: SiO2 TiO2 Al2O3 Fe2O3 Cr2O3 FeO MnO MgO NiO CoO CaO Na2O K2O P2O5 H2O
98.8228 g 59.87 0.63 17.73 0.98 0.00 4.13 0.13 2.91 0.00 0.00 7.08 2.86 1.67 0.00 2.02
Activity of H2O = 0.21086 Melt fraction = 0.994465
clinopyroxene: 0.550002 g, composition Na0.02Ca0.73Fe''0.23Mg0.90Fe'''0.05Ti0.01Al0.20Si1.88O6
find liquids
Initial alphaMELTS calculation at: P 4000.000000 (bars), T 1113.281250 (C)
liquid: SiO2 TiO2 Al2O3 Fe2O3 Cr2O3 FeO MnO MgO NiO CoO CaO Na2O K2O P2O5 H2O
99.3730 g 59.82 0.63 17.66 0.99 0.00 4.14 0.13 2.98 0.00 0.00 7.14 2.84 1.66 0.00 2.01
Activity of H2O = 0.209584 Melt fraction = 1
not same
find wet liquids
Initial alphaMELTS calculation at: P 4000.000000 (bars), T 1113.085938 (C)
liquid: SiO2 TiO2 Al2O3 Fe2O3 Cr2O3 FeO MnO MgO NiO CoO CaO Na2O K2O P2O5 H2O
98.8228 g 59.87 0.63 17.73 0.98 0.00 4.13 0.13 2.91 0.00 0.00 7.08 2.86 1.67 0.00 2.02
Activity of H2O = 0.21086 Melt fraction = 0.994465
clinopyroxene: 0.550002 g, composition Na0.02Ca0.73Fe''0.23Mg0.90Fe'''0.05Ti0.01Al0.20Si1.88O6
find liquids
Initial alphaMELTS calculation at: P 4000.000000 (bars), T 1113.281250 (C)
liquid: SiO2 TiO2 Al2O3 Fe2O3 Cr2O3 FeO MnO MgO NiO CoO CaO Na2O K2O P2O5 H2O
99.3730 g 59.82 0.63 17.66 0.99 0.00 4.14 0.13 2.98 0.00 0.00 7.14 2.84 1.66 0.00 2.01
Activity of H2O = 0.209584 Melt fraction = 1
not same
#6
The MELTS family of algorithms, and scientific discussion / how to suppress mineral in py ...
Last post by Kai Wen - June 24, 2025, 06:56:14 AMHello,
I tried to use 2.3.1 alphamelts-py to stimulate magmatic processes. How could I set the suppress phase?
Moreover, in the app, we could find liquid temperature for wet or not, but we could not find that function in Python. Does that influence the calculation?
Many thanks.
Best,
Kai
I tried to use 2.3.1 alphamelts-py to stimulate magmatic processes. How could I set the suppress phase?
Moreover, in the app, we could find liquid temperature for wet or not, but we could not find that function in Python. Does that influence the calculation?
Many thanks.
Best,
Kai
#7
General usage / Re: MELTS_Excel
Last post by Renqiang Liao - June 09, 2025, 06:59:29 PMDear Paula,
Thank you very much. It worked.
Best regards,
Renqiang
Thank you very much. It worked.
Best regards,
Renqiang
#8
General usage / Re: MELTS_Excel
Last post by Paula - June 09, 2025, 09:33:13 AMThe link to the latest version (currently 2024Jun18) is in this thread:
https://magmasource.caltech.edu/forum/index.php/topic,1053.msg1738.html#msg1738
Also on the alphaMELTS links page:
https://magmasource.caltech.edu/alphamelts/links.php
https://magmasource.caltech.edu/forum/index.php/topic,1053.msg1738.html#msg1738
Also on the alphaMELTS links page:
https://magmasource.caltech.edu/alphamelts/links.php
#9
General usage / MELTS_Excel
Last post by Renqiang Liao - June 09, 2025, 01:48:14 AMHi, everyone
Which is the latest MELTS_Excel version now? 2020Dec16 or 2024Jun18? The version 2020Dec16 shows "Server returned no results, giving up!". I read the message uploaded https://magmasource.caltech.edu/forum/index.php/topic,827.0.html, but it still does not work.
I saw a new version titled "MELTS_Excel 2024Jun18" on a social media, and this version seems to work. But the link "https://melts.ofm-research.org/excel.html" still is the version 2020Dec16. So I want to know where to download the version 2024Jun18.
Thanks in advance
Renqiang
Which is the latest MELTS_Excel version now? 2020Dec16 or 2024Jun18? The version 2020Dec16 shows "Server returned no results, giving up!". I read the message uploaded https://magmasource.caltech.edu/forum/index.php/topic,827.0.html, but it still does not work.
I saw a new version titled "MELTS_Excel 2024Jun18" on a social media, and this version seems to work. But the link "https://melts.ofm-research.org/excel.html" still is the version 2020Dec16. So I want to know where to download the version 2024Jun18.
Thanks in advance
Renqiang
#10
News and updates / Re: Melts Calculations Slowing...
Last post by Kai Wen - April 25, 2025, 02:58:04 PMHello，I am a new phd in cardiff uk, could you please help me how to use batch file