F igure 1. Isobaric distribution for partitioning of Ni between Mg-Fe-Ni olivine and Fe-Ni monosulfide liquid at 1385 °C in controlled atmosphere experiments (pluses; series A 2 of Fleet and MacRae 1988 ; Fleet 1989 ). From Equation 3, logγ Ni is given by the difference between the activity

Fig. 8 Mg# (molar Mg/(Fe + Mg)) vs. Ni concentration in olivine and serpentine. Closed triangles and squares represent olivine compositions from sulfide-bearing and low-sulfide assemblages, respectively. Open triangles and squares represent serpentine compositions from sulfide-bearing and low

Fig. 5. Ni/(Mg/Fe)/1000 versus 100Mn/Fe in olivine phenocrysts from the BTJ tholeiites. The fields for pyroxenite and peridotite are from Sobolev et al. (2007) . The remaining symbols are the same as in Fig. 4 .

F igure 6. Partition coefficient, D i olivine/melt , for i = Fe 2+ , Mg, Mn, Co, Ni, and Ca, as a function of NBO/T of the melt in the temperature range 1350–1375 °C. See text for discussion of published data (open circles). Regression parameters for the fits are shown in Table 4 . Filled

-monzodiorites (QMD). ( a ) Mg/(Mg+Fe) vs. Ti/Sm. ( b ) Mg/(Mg+Fe) vs. Sc/Sm. ( c ) Mg/(Mg+Fe) vs. Th. ( d ) Mg/(Mg+Fe) vs. Cr. ( e ) Mg/(Mg+Fe) vs. Ni. ( f ) Co vs. Ni.

Figure 17. Model for generation of Ni-enriched olivine by “cannibalization” of previously formed sulfide. ( a ) Initial formation of Ni-rich sulfide liquid pool from an Mg-rich magma. ( b ) Flushing of flow pathway by more evolved magma carrying relatively low-Fo, Fe-enriched olivine. Reaction

Figure 4. Temperature ( T ) dependencies of phase compositions in the olivine-pyrite system. Initial olivine—FeO or NiO content in initial olivine. Initial pyrite—Fe or Ni content in initial pyrite. L—predominantly sulfur melt with varying quantity of Fe, Ni, and O (±Mg, Si) dissolved.

Figure 4. (A–D) Ca, Ni, Mn, and Fe/Mn vs. Fo content [Fo = molar Mg/(Mg + Fe) × 100%] for the Piqiang olivines (analyzed by electron probe microanalysis [EPMA]). Olivine data for mid-ocean-ridge basalt (MORB), Koolau (Hawaii), Iceland, and komatiites are from Sobolev et al. (2005) . (E) Mn vs

= (Mg 0.895 Fe 0.099 Ni 0.006 ) 2 SiO 4 (0.6 wt% NiO, upper bound of NiO concentration in olivine phenocrysts of the Hawaiian tholeiitic lava, Lynn et al. 2017). Magenta solid line = (Mg 0.855 Fe 0.095 Ni 0.05 ) 2 SiO 4 (5 wt% NiO, upper bound of NiO concentration found in the peridotite xenolith from

(equilibrium mode gave very similar results) of a basaltic composition at the quartz-fayalite-magnetite oxygen buffer (QFM) and 100 MPa (panels a, c, e, g of the figure). The olivine end members are Fo mol% = 100· Mg/(Mg+Fe+Ca+Mn+Ni), Tephro mol% = 100·Mn/(Mg+Fe+Ca+Mn+Ni), Mont = 100·Ca/(Mg+Fe+Ca+Mn+Ni), Ni-Ol

concentric zones dominated by Fe serpentine and Mg serpentine surrounding relict olivine grains. B) Awaruite replacing pentlandite (EXP_037); assemblage described by reaction 13 . C) Heazlewoodite replacing pentlandite in EXP_648; assemblage described by reaction 14 . D) BSE image of submicron-scale Ni-Fe

Fig. 7. Plot of olivine Ni vs. Fo content; this work and literature data ( Li et al., 2015 ; Zhang et al., 2017 ; Liu et al., 2018 ; Song et al., 2020 ). Fo=molar Mg/(Mg+Fe) × 100.

Figure 8. (A) Plot of Ni contents versus Fo contents of olivine in the Ni-Cu sulfide- and Fe-Ti oxide-bearing rocks of the Kebu intrusion. (B) Plot of FeO contents versus Mg# of orthopyroxene in the Fe-Ti oxide-bearing rocks of the Kebu intrusion. (C) Plot of FeO versus An of plagioclase