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Table 3 Chemical composition of melt inclusions in the scoria from the 1979, 1989, and 2014 eruptions analyzed by EPMA and SIMS (wt%). Gas saturation pressure calculated from the H2O and CO2 content of the melt inclusions and temperature and pressure of the magma estimated with thermobarometers proposed by Putirka (2008) are also shown

From: Petrological characteristics and volatile content of magma of the 1979, 1989, and 2014 eruptions of Nakadake, Aso volcano, Japan

  1979.6.16 scoria      
Sample ID AS790616S AS790616S AS790616S AS790616S AS790616S AS790616S
MI no. mts10120601-2-p6i2 mts10120608-2-p5i1 mts10120601-3-p2i1 mts10120601-3-p2i2 mts10120608-2-p3i1 mts10120608-2-p4i1
Host phenocryst Pl(An66) Pl(An63) Cpx(Wo37En44Fs19 Mg#70) Cpx(Wo38En43Fs18 Mg#70) Cpx(Wo37En44Fs19 Mg#70) Cpx(Wo38En43Fs19 Mg#69)
Size of MI 0.12 × 0.05 (mm) 0.10 × 0.04 (mm) 0.08 × 0.05 (mm) 0.10 × 0.10 (mm) 0.06 × 0.04 (mm) 0.07 × 0.06 (mm)
SiO2 54.39 59.57 56.01 55.81 56.22 58.35
TiO2 1.49 1.14 1.41 1.30 1.36 1.35
Al2O3 14.03 14.27 13.68 13.47 14.19 13.41
FeOt 10.20 6.99 10.59 11.53 9.09 9.11
MnO 0.18 0.09 0.19 0.25 0.17 0.19
MgO 2.88 1.85 2.46 2.81 2.36 2.12
CaO 5.68 4.57 5.75 5.98 5.18 4.74
Na2O 2.99 3.18 2.71 2.78 3.28 2.74
K2O 3.26 4.21 3.25 3.08 3.79 4.28
P2O5 0.32 0.12 0.26 0.23 0.32 0.29
S 0.021 0.013 0.015 0.019 0.010 0.018
Cl 0.075 0.065 0.071 0.074 0.074 0.088
H2O (SIMS/EPMA)a 0.3/1.3 1.2/1.0 0.6/0.9 0.6/0.5 0.9/1.0 1.3/0.8
CO2 (SIMS)b 0.012 0.034 0.024 0.020 0.009 0.025
S(+ 6)/total Sc 0.2 0.3 0.8 0.6 n.a. 0.6
log fO d2 − 9 − 9 − 8 − 8 n.a. − 8
Fe(+ 2)/total Fee 0.7 0.8 0.8 0.7 n.a. 0.7
NNO (log unit)f − 0.4 0.0 0.8 0.5 n.a. 0.5
Sat. Press. (MPa)g 61 118 102 98 51 113
Temperature (°C)h 1066 1046 1074 1073 1062 1059
Pressure (MPa) (cpx–liquid)h    440 410 390 560
K iD 0.17 0.13 0.22 0.23 0.25 0.24
  1979.6.16 scoria 1989.11.24 scoria     
Sample ID AS790616S AS891124 AS891124 AS891124 AS891124 AS891124
MI no. mts10120608-2-p1i1 mts10120601-4-p1i1 mts10120601-4-p3i1 mts10120608-4-p1i1 mts10120608-4-p3i1 mts10120608-4-p3i2
Host phenocryst Ol(Fo65) Cpx(Wo38En44Fs18 Mg#71) Cpx(Wo37En43Fs20 Mg#68) Cpx(Wo37En43Fs20 Mg#69) Cpx(Wo39En43Fs19 Mg#70) Cpx(Wo40En43Fs18 Mg#71)
Size of MI 0.20 × 0.10 (mm) 0.20 × 0.10 (mm) 0.10 × 0.06 (mm) 0.15 × 0.10 (mm) 0.10 × 0.10 (mm) 0.09 × 0.09 (mm)
SiO2 57.66 58.40 59.24 58.44 59.71 57.92
TiO2 1.29 1.49 1.27 1.27 1.40 1.37
Al2O3 13.47 14.30 14.42 14.60 14.24 14.67
FeOt 9.78 9.92 8.09 8.97 7.99 9.57
MnO 0.17 0.18 0.14 0.16 0.18 0.24
MgO 2.51 1.99 1.93 1.99 1.91 1.65
CaO 5.22 5.17 5.15 4.95 5.74 4.79
Na2O 2.87 2.96 2.90 2.91 2.49 3.21
K2O 3.52 3.83 3.57 3.89 3.38 4.39
P2O5 0.29 0.36 0.27 0.29 0.28 0.23
S 0.018 0.016 0.015 0.012 0.015 0.019
Cl 0.087 0.090 0.070 0.086 0.081 0.080
H2O (SIMS/EPMA)a 1.6/0.7 0.6/0.2 0.5/0.6 0.5/0.4 0.5/0.5 0.3/0.3
CO2 (SIMS)b 0.007 0.009 0.004 0.007 0.006 0.003
S(+ 6)/total Sc 0.5 0.1 0.7 0.0 0.1 0.1
log fO d2 − 9 − 10 − 8 − 10 − 9 − 10
Fe(+ 2)/total Fee 0.8 0.9 0.7 0.9 0.8 0.9
NNO (log unit)f 0.2 − 0.9 0.7 − 1.2 − 0.5 − 0.9
Sat. Press. (MPa)g 53 50 18 37 22 21
Temperature (°C)h 1034 1058 1071 1055 1068 1031
Pressure (MPa) (cpx–liquid)h   460 560 440 470 280
K iD 0.31 0.18 0.25 0.22 0.23 0.16
  2014.11.26–27 scoria     
Sample ID I141129S01 I141129S I141129S I141129S02 I141129S03
MI no. mts16041403-2-p1i1 mts16041403-4-p1i1 mts16041403-4-p1i2 I141129S02-1-p4i1 I141129S03-1-p1i1
Host phenocryst Pl(An60) Pl(An65) Pl(An65) Pl(An76) Pl(An63)
Size of MI 0.10 × 0.08 (mm) 0.10 × 0.04 (mm) 0.08 × 0.04 (mm) 0.05 × 0.02 (mm) 0.04 × 0.01 (mm)
SiO2 62.12 57.96 57.65 56.33 56.21
TiO2 0.91 1.32 1.34 1.38 1.32
Al2O3 14.51 14.36 14.34 13.35 13.39
FeOt 7.53 9.47 9.80 9.30 9.09
MnO 0.14 0.14 0.16 0.18 0.21
MgO 1.96 2.99 2.66 2.71 2.75
CaO 4.30 5.92 5.58 5.53 5.03
Na2O 3.10 3.02 3.27 2.60 2.65
K2O 4.66 3.52 3.68 3.54 3.86
P2O5 0.31 0.64 0.62 0.31 0.23
S 0.008 0.015 0.014 0.018 0.029
Cl 0.055 0.087 0.075 0.075 0.071
H2O (SIMS/EPMA)a 0.8/0.1 0.7/0.2 0.7/0.3 na/1.5 na/2.0
CO2 (SIMS)b 0.002 0.008 0.017 na na
S(+ 6)/total Sc 0.1 0.4 0.1 na na
log fO d2 − 9 − 9 − 9 na na
Fe(+ 2)/total Fee 0.8 0.8 0.8 na na
NNO (log unit)f − 0.5 0.1 − 0.4 na na
Sat. Press. (MPa)g 27 41 80 na na
Temperature (°C)h 1040 1081 1078 1059 1027
Pressure (MPa) (cpx–liquid)h      
K iD 0.14 0.17 0.15 0.11 0.18
  2014.11.26–27 scoria     
Sample ID I141129S I141129S02 I141129S01 I141129S I141129S02
MI no. mts16041403-4-p2i1 I141129S02-1-p11i2 mts16041403-2-p2i1 mts16041403-3-p1i1 I141129S02-1-p12i1
Host phenocryst Cpx(Wo38En43Fs19 Mg#69) Cpx(Wo38En45Fs18 Mg#71) Ol(Fo67) Ol(Fo66) Ol(Fo67)
Size of MI 0.10 × 0.05 (mm) 0.02 × 0.02 (mm) 0.08 × 0.07 (mm) 0.20 × 0.20 (mm) 0.02 × 0.02 (mm)
SiO2 58.21 54.89 57.93 58.11 56.34
TiO2 1.21 1.45 1.38 1.20 1.34
Al2O3 14.55 14.35 14.51 14.37 14.13
FeOt 9.69 9.50 9.99 9.43 9.02
MnO 0.21 0.17 0.15 0.19 0.15
MgO 2.71 2.28 2.64 2.55 2.50
CaO 5.67 5.96 5.89 5.66 5.66
Na2O 3.67 3.14 3.07 2.92 2.97
K2O 3.05 3.25 3.43 3.64 3.45
P2O5 0.44 0.24 0.52 0.51 0.23
S 0.009 0.036 0.013 0.010 0.019
Cl 0.074 0.079 0.068 0.079 0.072
H2O(SIMS/EPMA)a 0.6/0.1 na/1.5 0.7/0.1 0.7/0.6 na/1.0
CO2 (SIMS)b nd na 0.003 0.004 na
S(+ 6)/total Sc na na 0.4 0.7 na
log fO d2 na na − 9 − 8 na
Fe(+ 2)/total Fee na na 0.8 0.7 na
NNO (log unit)f na na 0.1 0.7 na
Sat. Press. (MPa)g na na 22 25 na
Temperature (°C)h 1071 1072 1046 1046 1042
Pressure (MPa) (cpx–liquid)h 420 460    
K iD 0.28 0.21 0.30 0.31 0.31
  1. KD of the melt inclusions in olivines = (X(ol-Fe)/X(ol-Mg))/(X(liq-FeO)/X(liq-MgO)). X(ol-Fe) and X(ol-Mg) are mol fractions of fayalite and forsterite in olivine, and X(liq-FeO) and X(liq-MgO) are cation fraction of Fe(+ 2) and Mg in the melt. The mol fraction ratio of Fe(+ 2) to total Fe in the melt was assumed to be 0.8. At equilibrium, this KD is 0.299 ± 0.053 for P<2 GPa (Putirka 2008)
  2. KD of the clinopyroxene-hosted inclusions = − (X(cpx-Fe)/X(cpx-Mg))/(X(liq-FeO)/X(liq-MgO)). X(cpx-Fe) and X(cpx-Mg) are mol fractions of forsterite and enstatite in clinopyroxene, and X(liq-FeO) and X(liq-MgO) are cation fraction of Fe(+ 2) and Mg in the melt. The mol fraction ratio of Fe(+ 2) to total Fe in the melt was assumed to be 0.8. At equilibrium, this KD is 0.28 ± 0.08 (Putirka 2008)
  3. FeOt, total FeO; nd, not detected; na, not analyzed
  4. ax/y: x, analyzed by SIMS, y, analyzed by EPMA. The analytical errors is ± 0.2 wt% for SIMS (Saito et al. 2010) and ± 1 wt% for EPMA
  5. bThe analytical error is ± 0.0028 wt% (Saito et al. 2010)
  6. cMol fractions of S(+ 6) in total S in the melt inclusions calculated from the S Kα radiation wavelength measured by EPMA, assuming that all S in the inclusions is composed of S(+ 6) and S(− 2)
  7. dCalculated from the mol fraction of S(+ 6) in total S in the inclusions by Wallace and Carmichael (1994), assuming temperature of 1079 °C
  8. eCalculated from the oxygen fugacity and chemical composition of the inclusions by Kilinc et al. (1983), assuming temperature of 1079 °C
  9. fEstimates with 1079 °C
  10. gSaturation pressures calculated from H2O and CO2 contents of the melt inclusions using the solubility model of Papale et al. (2006). An online version of the Papale’s solubility model (http://melts.ofm-research.org/CORBA_CTserver/Papale/Papale.php) was used for these calculations. The mol ratio of Fe(+ 2) to total Fe in the melt and temperature was assumed to be 0.8 and 1079 °C, respectively
  11. hTemperatures of the melt inclusions in plagioclases were estimated from chemical compositions of the melt and their host phenocrysts using plagioclase–liquid thermometer by Putirka (2008, Eq. (24a)). This thermometer yields a standard error of estimate (SEE) of 36 °C. Temperature of the melt inclusions in olivines was estimated from chemical compositions of the melt and their host phenocrysts using olivine–liquid thermometer by Putirka (2008, Eq. (22)). This thermometer yields SEE of 29 °C. Temperature and pressure of the melt inclusions in clinopyroxenes were estimated from chemical compositions of the melt and their host phenocrysts using clinopyroxene–liquid thermobarometers by Putirka (2008; Eqs. (31) and (33)). These thermobarometers yield SEE of 42 °C and 290 MPa. Saturation pressures and H2O contents of the melt inclusions analyzed by SIMS were used for this calculationin. If the saturation pressures were not determined, pressure of 100 MPa was assumed. If the inclusions were not analyzed by SIMS, the H2O contents analyzed by EPMA were used
  12. iKD of the melt inclusions in plagioclases = X(pl-Ab)X(liq-AlO1.5)X(liq-CaO)/(X(pl-An)X(liq-NaO0.5)X(liq-SiO2)). X(pl-Ab) and X(pl-An) are mol fraction of albite and anorthite in plagioclase, and X(liq-AlO1.5), X(liq-CaO), X(liq-NaO0.5) and X(liq-SiO2) are cation fractions of Al, Ca, Na and Si in the melt (Putirka 2008). At equilibrium, this KD is 0.10 ± 0.05 for T < 1050 °C, and 0.27 ± 0.11 for T ≥ 1050 °C (Putirka 2008)