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Greetings colleagues!

I know it's a lot massages from me on the forum last weeks.
I've read the topic about nagative poroptions of end memebers in spinel that is published here a time ago, but I observe the large values of negative propotions and it's confusing.
What is the right way to interpretate this data?

Title: osyb9

T = 1205,00 (C)  P = 9,000 (kbars)  log(10) f O2 = -7,58  delta HM = -4,92  NNO = -0,07  QFM = 0,00  COH = 1,83  IW = 4,11

Constraint Flags: fO2 path = QFM 

Liquid           mass = 27,95 (gm)  density = 3,09 (gm/cc)  viscosity = 1,49 (log 10 poise)     (analysis in wt %)
      G = -388332,13 (J)  H = -280978,92 (J)  S = 72,63 (J/K)  V = 9,05 (cc)  Cp = 38,42 (J/K) 
        SiO2   TiO2  Al2O3  Fe2O3  Cr2O3    FeO    MnO    MgO    NiO    CoO    CaO   Na2O    K2O   P2O5    H2O    CO2    SO3 Cl2O-1  F2O-1
       41,29   5,16  13,04   2,97   0,00  23,16   1,04   3,10   0,00   0,00   7,64   2,61   0,00   0,00   0,00   0,00   0,00   0,00   0,00

clinopyroxene    mass = 30,84 (gm)  density = 3,39 (gm/cc)     (analysis in mole %)
                 cpx Na0,06Ca0,63Fe''0,41Mg0,61Fe'''0,12Ti0,05Al0,41Si1,72O6
                 G = -463007,38 (J)  H = -356018,61 (J)  S = 72,38 (J/K)  V = 9,09 (cc)  Cp = 35,52 (J/K) 
           diopside clinoenstatit  hedenbergite alumino-buffo     buffonite      essenite       jadeite
              -6,76         31,38         41,26         16,54         -7,09         18,89          5,77

clinopyroxene    mass = 14,56 (gm)  density = 3,42 (gm/cc)     (analysis in mole %)
                 cpx Na0,03Ca0,32Fe''0,62Mg0,79Fe'''0,09Ti0,02Al0,35Si1,77O6
                 G = -212375,73 (J)  H = -161371,57 (J)  S = 34,51 (J/K)  V = 4,25 (cc)  Cp = 16,95 (J/K) 
           diopside clinoenstatit  hedenbergite alumino-buffo     buffonite      essenite       jadeite
             -53,03         64,95         62,06         13,29         -9,29         18,66          3,35

feldspar         mass = 26,90 (gm)  density = 2,65 (gm/cc)     (analysis in mole %)
                 K0,00Na0,47Ca0,53Al1,53Si2,47O8
                 G = -459947,06 (J)  H = -361093,18 (J)  S = 66,88 (J/K)  V = 10,14 (cc)  Cp = 33,22 (J/K) 
             albite     anorthite      sanidine
              46,73         53,27          0,00

Total solids     mass = 72,31 (gm)  density = 3,08 (gm/cc)
                 G = -1135330,17 (J)  H = -878483,36 (J)  S = 173,76 (J/K)  V = 23,49 (cc)  Cp = 85,69 (J/K) 

Viscosity of the System cannot be computed.

System           mass = 100,26 (gm)  density = 3,08 (gm/cc)
                 G = -1523662,30 (J)  H = -1159462,28 (J)  S = 246,39 (J/K)  V = 32,54 (cc)  Cp = 124,11 (J/K) 

Oxygen           delta moles = 0,00145398  delta grams = 0,0465258
                 G = -495,59 (J)  H = 57,85 (J)  S = 0,37 (J/K)  V = 178,69 (cc)  Cp = 0,05 (J/K) 

[Initial parameters:]

Thank you for answers!

What is the aegirine content of the pyroxene that MELTS predicts?

Now MELTs predicts no aegerine.
As I understand from the answers It's more about features of Cpx solid solution model is used in MELTs code.

I've attached here the Cpx compositions are predicted by MELTs and initial parameters.

Initial parameters:
Initial Composition: SiO2 46,8800
Initial Composition: TiO2 2,0500
Initial Composition: Al2O3 15,3600
Initial Composition: FeO 15,6000
Initial Composition: MgO 6,1800
Initial Composition: CaO 10,7900
Initial Composition: Na2O 2,4700
Initial Temperature: 1400,00
Final Temperature: 900,00
Initial Pressure: 9000,00
Final Pressure: 9000,00
Increment Temperature: 5,00
Increment Pressure: 0,00
dp/dt: 0,00
log fo2 Path: FMQ

Here is a link to file with Cpx compositions: https://dropmefiles.com/xkaHh

Greetings colleagues!

Is it possible to turn off buffonite and essenite end members of clinopyroxene in rhyolite-MELTs?
In my samples I have a significant amount of Fe³⁺ that provides aegerine existence (it's approved by recalculation of composition). But MELTs places all of the ferric into buffonite and essenite so aegerine is absent.
Aegerine containig is really important for our study.

Dear Paula!
Thank you very much, it helps a lot!
Everything works now  :D

[Initial parameters:]

Greetings colleagues!

It;s my first experience with MELTs software.

I successfully have installed rhyolite-Melts on Linux. It works, but only particularly.
The program is able to find liquids for the bulk composition is used but the problem occurs when I try to set the "execution/halt" command. I always received the massage about quadratic converge that is failed after 101 iterations. Is there any problems with my initial parameters here? I tried to change P-T parameters, to add buffer path, to execute under unchanged T - unfortunately, it doesn't help.

I'm looking forward help!
Thank everyone in advance :)

Initial parameters:
Initial Composition: SiO2 46,7510
Initial Composition: TiO2 1,7274
Initial Composition: Al2O3 15,5268
Initial Composition: FeO 14,9041
Initial Composition: MgO 7,3114
Initial Composition: CaO 11,7104
Initial Composition: Na2O 2,0689
Initial Temperature: 1200,00
Final Temperature: 900,00
Initial Pressure: 9000,00
Final Pressure: 9000,00
Increment Temperature: 5,00
Increment Pressure: 0,00
dp/dt: 0,00
log fo2 Path: None