CaO-MgO-SiO2
The experiments of Brey et al. (1983) on the pressure-sensitive reaction di + 2mag = en + dol are now well fitted, in contrast with HP90, and provide a strong constraint on the enthalpy of dolomite. The experiments of Jenkins et al. (1991) for the reactions 2di + ta = tr and 2tr = 3en + 4di +2q + 2H2O help to constrain talc and tremolite enthalpies more tightly. Although most reactions in this subsystem are well fitted by the new data set, the experiments of Kase & Metz (1980) on the reaction di + 3 dol = 2fo + 4cc + 2CO2 are missed (calculated temperatures are 10-17°C too high), as are the high-pressure brackets of Goldsmith (1980) for the reaction dol = cc + per + CO2 and the very-high-pressure (above 50 kbar) data of Luth (1995) for the reaction dol + q = di + 2CO2.
42) wo + mont = ak (Yoder, 1968)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 - 1.0 675 700 20.19 20.67 4 704 10 3 (20.52 <-> 20.79)
0 - 3.0 705 720 20.52 20.81 717 10 cH = 20.75 (sd 0.09)
0 - 5.0 720 750 20.56 21.13 730 10 within bracket
0 - 6.0 720 750 20.43 21.00 737 10 uH = 0.10, d/s = 0.6, h = 0.82
43) di + merw = 2ak (Yoder, 1968)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 - 7.5 780 14.64 850 20 3 (15.73 <-> 16.55)
0 - 7.0 810 16.43 1 811 18 cH = 16.45 (sd 0.24)
0 - 9.0 950 980 15.97 16.73 969 20 within bracket
0 - 10.0 1020 1050 15.73 16.50 1048 20 uH = 0.35, d/s = 0.7, h = 0.42
44) di + 3mont = fo + 2ak (Walter, 1963; Yoder, 1968)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 - 0.2 860 875 56.44 57.10 873 8 3 (56.77 <-> 57.46)
0 - 0.4 880 895 57.16 57.81 -4 876 8 cH = 56.99 (sd 0.17)
0 - 2.0 890 910 56.32 57.20 905 8 within bracket
0 - 5.0 950 975 56.54 57.63 960 8 uH = 0.25, d/s = -0.4, h = 0.89
0 - 10.0 1060 1090 57.29 58.61 -7 1053 8
45) 2di + ta = tr (Jenkins,Holland & Clare, 1991)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.16 - 27.0 24.0 650 -8.53 -6.91 25.52 0.64 3 (-8.18 <-> -7.41)
-0.16 - 26.5 26.0 700 -8.10 -7.83 -0.18 25.82 0.63 cH = -7.73 (sd 0.17)
-0.16 - 26.0 25.0 725 -7.75 -7.20 25.96 0.62 within bracket
-0.16 - 27.0 26.0 750 -8.22 -7.66 26.11 0.62 uH = 0.33, d/s = -0.1, h = 0.60
46) di + 2mag = en + dol (Brey et al., 1983)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.01 - 23.0 20.0 850 9.76 10.91 20.03 2.92 3 (9.59 <-> 11.16)
0.05 - 28.5 25.5 970 9.83 10.92 25.55 3.11 cH = 10.90 (sd 0.56) 3
0.12 - 35.5 33.5 1100 9.92 10.59 -0.92 32.58 3.38 within bracket
0.15 - 41.5 39.5 1200 10.37 11.00 39.80 3.69 uH = 0.67, d/s = 0.1, h = 0.35
0.18 - 49.5 47.5 1300 10.46 11.03 47.95 4.09
47) spu + 2mont = 2merw + cc (Walter, 1965)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 - 0.3 812 824 54.49 55.05 6 830 12 2 (54.81 <-> 55.39)
0 - 1.0 800 820 55.16 56.08 804 12 cH = 55.33 (sd 0.25)
within bracket
uH = 0.23, d/s = -0.2, h = 0.93
48) 2tr = 3en + 4di + 2q + 2H2O (Yin & Greenwood, 1983)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0 0.1 655 675 228.76 233.45 674 4 3 (231.51 <-> 234.29)
0 0 0.2 725 745 231.33 235.65 733 4 cH = 233.12 (sd 0.36)
0 0 0.3 755 775 232.93 237.11 756 4 within bracket
0 0 0.8 800 820 231.08 234.87 811 4 uH = 0.99, d/s = -0.4, h = 0.17
0 0 1.4 820 840 228.68 232.19 5 845 4
* 2tr = 3en + 4di + 2q + 2H2O (Boyd, 1959)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0 0.6 795 820 233.71 238.63 -3 792 4 ** NOT USED **
0 0 1.0 835 850 234.98 237.75 -10 825 4 cH = 233.12 (sd 0.36)
0 0 1.5 840 870 231.50 236.73 849 4
0 0 2.0 860 880 232.21 235.56 865 4
49) 2tr = 3en + 4di + 2q + 2H2O (Jenkins, Holland & Clare, 1991)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0 1.5 840 860 231.50 234.99 849 4 3 (232.88 <-> 234.91)
0 0 3.0 880 232.12 886 4 cH = 233.12 (sd 0.36)
0 0 2.9 888 233.65 885 4 within bracket
0 0 5.0 914 930 234.17 236.55 -7 907 4 uH = 0.78, d/s = -0.3, h = 0.24
0 0 7.1 916 929 233.31 235.16 -1 915 6
50) 2tr + 2fo = 5en + 4di + 2H2O (Jenkins, 1983)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0.09 0 5.0 820 840 216.51 219.36 831 6 3 (214.97 <-> 218.25)
0.09 0 8.0 790 810 214.73 217.38 5 815 6 cH = 218.06 (sd 0.39)
0.09 0 10.0 770 790 214.65 217.22 7 797 6 within bracket
0.09 0 20.0 640 660 216.09 218.39 657 8 uH = 1.39, d/s = 0.3, h = 0.19
* dol = cc + per + CO2 (Goldsmith, 1980)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.14 1 9.0 1125 1140 118.23 119.30 36 1176 12 ** NOT USED **
-0.14 1 9.5 1125 1150 117.04 118.82 43 1193 14 cH = 121.86 (sd 0.46)
-0.14 1 10.5 1050 109.36 1227 14
-0.14 1 11.0 1180 117.55 63 1243 14
* dol = cc + per + CO2 (Harker & Tuttle, 1955)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.12 1 0.3 700 800 121.48 132.75 703 8 ** NOT USED **
-0.12 1 0.7 780 820 123.97 128.16 -20 760 8 cH = 121.86 (sd 0.46)
-0.13 1 1.0 800 850 122.21 127.24 -3 797 10
-0.13 1 2.8 900 950 120.30 124.75 918 10
51) dol + 2q = di + 2CO2 (Slaughter et al., 75; Eggert & Kerrick, 1981; Jacobs & Kerrick, 1981)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0.95 2.0 505 525 156.20 159.63 508 6 3 (156.35 <-> 158.86)
0 0.73 6.0 610 630 156.32 159.37 613 6 cH = 156.76 (sd 0.48) 2
0 0.60 5.0 565 585 155.27 158.50 574 6 within bracket
uH = 0.90, d/s = 1.2, h = 0.07
52) dol + 2q = di + 2CO2 (Eggler et al., 1976)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 1 28.0 970 1025 152.29 158.03 1013 10 1 (152.91 <-> 157.40)
cH = 156.76 (sd 0.48) 2
within bracket
uH = 0.92, d/s = 3.1, h = 0.01
* dol + 2q = di + 2CO2 (Luth, 1995)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 1 35.0 1100 1150 156.58 161.25 1102 10 ** NOT USED **
0 1 40.0 1150 1200 155.57 159.97 1163 10 cH = 156.76 (sd 0.48)
0 1 50.0 1300 1350 158.15 162.09 -17 1283 12
0 1 60.0 1500 1550 163.92 167.36 -101 1399 14
53) di + 3dol = 2fo + 4cc + 2CO2 (Kase & Metz, 1980)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.33 0.90 3.0 623 653 207.27 213.48 9 662 12 3 (209.30 <-> 212.88)
-0.38 0.90 5.0 700 720 208.51 212.41 15 735 14 cH = 215.34 (sd 1.33) 2
-0.47 0.90 10.0 850 870 209.90 213.46 11 881 16 too high but OK
uH = 1.43, d/s = 0.9, h = 0.25
54) 2dol + ta + 4q = tr + 4CO2 (Eggert & Kerrick, 1981)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0.22 6.0 540 560 309.91 317.29 -11 529 6 2 (309.20 <-> 315.04)
0 0.21 6.0 530 550 306.88 314.33 -3 527 6 cH = 305.80 (sd 0.98) 2
too low
uH = 2.09, d/s = 1.1, h = 0.04
55) di + cc = ak + CO2 (Walter, 1963)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0.05 1 0.5 895 905 151.97 153.12 -14 881 4 2 (151.59 <-> 153.10)
0.05 1 0.7 920 930 151.61 152.73 -11 909 4 cH = 150.36 (sd 0.25)
too low
uH = 0.64, d/s = 0.6, h = 0.19
56) ak + fo + cc = 3mont + CO2 (Walter, 1963)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0.05 1 0.5 885 905 93.52 94.95 -2 883 8 2 (92.93 <-> 94.19)
0.05 1 0.7 910 930 92.24 93.60 927 8 cH = 93.37 (sd 0.28)
within bracket
uH = 0.45, d/s = 0.1, h = 0.30
57) fo + di + 2cc = 3mont + 2CO2 (Walter, 1963)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0.10 1 0.5 885 905 244.33 248.07 -3 882 6 1 (244.55 <-> 247.85)
cH = 243.73 (sd 0.51)
too low but OK
uH = 1.10, d/s = 1.7, h = 0.07
58) 5dol + 4ta = 6fo + 5di + 4H2O + 10CO2 (Skippen, 1971)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0.75 1.0 500 540 1242.03 1296.56 516 4 1 (1252.32 <-> 1273.66)
0 0.75 2.0 550 570 1250.34 1275.64 561 4 cH = 1264.30 (sd 2.62) 2
within bracket
uH = 6.60, d/s = 1.9, h = 0.01
59) ta + 3cc + 2q = 3di + H2O + 3CO2 (Skippen, 1971)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0.60 2.0 480 515 307.07 318.61 493 6 1 (308.31 <-> 317.37)
cH = 311.33 (sd 1.02) 2
within bracket
uH = 1.71, d/s = 3.4, h = 0.01
60) 5dol + 8q + H2O = tr + 3cc + 7CO2 (Slaughter et al., 1975; Eggert & Kerrick, 1981)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.12 0.85 2.0 474 494 459.00 470.01 484 8 3 (464.69 <-> 473.73)
-0.22 0.66 6.0 590 610 462.95 472.87 594 8 cH = 464.75 (sd 2.06) 2
-0.19 0.21 6.0 540 560 470.27 482.37 -9 531 6 within bracket
-0.19 0.21 6.0 530 550 464.19 476.33 531 6 uH = 3.23, d/s = -0.0, h = 0.14
61) 5ta + 6cc + 4q = 3tr + 6CO2 + 2H2O (Slaughter et al., 1975;)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0.50 2.0 425 465 586.60 613.78 444 6 1 (589.32 <-> 611.06)
cH = 599.49 (sd 2.13) 2
within bracket
uH = 3.51, d/s = 3.9, h = 0.01
62) 3dol + 4q + H2O = ta + 3cc + 3CO2 (Eggert & Kerrick, 1981; Metz & Puhan, 1971; Gordon & Greenwood)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.15 0.50 3.0 485 505 158.74 163.03 486 12 3 (158.25 <-> 161.83)
-0.19 0.50 5.0 550 570 157.30 161.30 558 12 cH = 158.95 (sd 1.26) 2
-0.19 0.25 6.0 540 560 157.56 162.10 546 12 within bracket
-0.09 0.45 2.0 450 161.46 -11 439 10 uH = 1.28, d/s = -0.1, h = 0.25
-0.12 0.57 2.0 472 163.07 453 12
-0.12 0.79 2.0 470 154.60 492 12
-0.15 0.76 2.0 497 161.62 484 12
-0.15 0.93 2.0 519 154.80 542 14
63) tr + 3cc + 2q = 5di + 3CO2 + H2O (Slaughter et al., 1975)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0.50 1.0 489 499 322.97 326.52 -11 478 6 2 (321.94 <-> 326.22)
0 0.90 1.0 476 496 318.12 325.18 479 6 cH = 319.06 (sd 1.03) 2
too low
uH = 1.82, d/s = 0.6, h = 0.07
64) tr + 11dol = 8fo + 13cc + 9CO2 + H2O (Metz, 1976)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
-0.67 0.50 1.0 525 545 1007.68 1030.28 539 8 3 (1007.41 <-> 1024.20)
-0.80 0.50 3.0 610 630 1005.48 1025.68 628 10 cH = 1023.65 (sd 4.69) 2
-1.08 0.50 5.0 670 690 1003.97 1024.23 691 10 within bracket
uH = 6.01, d/s = 1.4, h = 0.15
65) 3tr + 5cc = 11di + 2fo + 5CO2 + 3H2O (Chernosky & Berman, 1986)
ln_K x(CO2) P(kbar) T(C) H(low) H(high) miss calc 2sd summary
0 0.45 1.0 528 548 692.18 706.59 542 6 1 (693.35 <-> 705.42)
cH = 702.24 (sd 1.85) 2
within bracket
uH = 3.69, d/s = 2.0, h = 0.02
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