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Table 1 Fe–Ti oxide compositions calculated based on stoichiometry

From: New temperature and oxygen fugacity data of Martian nakhlite from Northwest Africa (NWA) 5790 and implications for shallow sulphur degassing

No. Tim1 Ilm1 Tim2 Ilm2 Tim3 Ilm3 Tim4 Ilm4
Occurrence Lamellae Lamellae Rim/veinlet Rim/veinlet
SiO2 0.20 0.21 0.23 0.31 0.08 0.25 0.09 1.46
TiO2 14.09 38.82 12.86 37.80 11.22 44.17 11.49 40.99
Al2O3 2.45 0.75 2.62 1.02 2.53 0.38 2.82 0.42
Cr2O3 2.48 1.15 2.28 1.49 2.25 0.68 2.15 0.66
FeO 41.23 31.47 40.39 30.55 38.86 37.45 39.65 32.45
Fe2O3 33.35 24.26 36.15 25.79 39.15 14.79 39.09 18.44
MgO 0.29 0.65 0.26 0.58 0.20 0.70 0.20 0.83
MnO 0.44 0.73 0.40 0.81 0.47 0.92 0.29 1.58
CaO 0.06 0.03 0.01 0.03 n.d 0.02 n.d 0.02
V2O3 0.50 n.d 0.50 n.d 0.50 n.d 0.50 n.d
ZnO n.d 0.10 n.d 0.10 n.d 0.10 n.d 0.10
Total 95.09 98.20 95.70 98.48 95.26 97.95 96.28 97.15
T (°C) 1032 1005 848 901
logfO2 − 9.05 − 9.30 − 12.39 − 11.15
ΔQFMa + 1.44 + 1.60 + 1.26 + 1.49
  1. n.d. not detected, Tim titanomagnetite, Ilm ilmenite
  2. aThe ΔQFM values were calculated using an equation from Frost (1991)