1. Magmatic Ni-Cu-PGE-Cr Deposits

2. Distribution of Magmatic Sulphide Deposits
Norilsk
Sudbury
Bushveld

3. Magmatic Sulphide Ore
(Pyrrhotite and subordinate pentlandite (Fe,Ni)8S9)

4. Ni Grades and Tonnages

5. Cu Grades and Tonnages

6. PGE Grades and Tonnages

7. Geology of the Sudbury Complex

8. Evidence of Meteorite Impact
Onaping fallback breccia
Shatter cones
Granophyre - impact melt

9. Meteorite Impact Origin of the Sudbury Complex
Airborne debris
Onaping
Ejecta
Breccia
Melt
Sulphide concentrations
Onaping formation
Partial
melting
Sublayer
Sudbury
Irruptive
Impact Stratigraphy
Sudbury Stratigraphy

10. Sudbury Footwall-Type Deposit

11. Sudbury Ni-Cu Ores Inclusion Ore Massive Ore Pyrrhotite-chalcopyrite
and peridotite inclusions
Chalcopyrite
Pyrrhotite
Pentlandite
Massive Ore
Pyrrhotite
Pentlandite (Fe,Ni)9S8

12. The Billiard Ball Model of Magmatic Sulphide Textures (Naldrett, 1969)

13. Fraser and Strathcona Mines Cross-Section

14. Footwall Ores
Chalcopyrite sill with alteration halo cuts off mafic dyke. High PGE into host gneiss
Pyrrhotite- and chalcopyrite-dominated veins in footwall gneiss

15. Oxygen/Sulphur Fugacity and FeO Controls on Sulphur solubility in Silicate Melts
Sulphur dissolves H2S at low
fO2 and as SO2 at high fO2

16. Metal partitioning between Sulphide and Silicate Melts
Wt.% Metal in Silicate Liquid
Wt.% Metal in Sulphide Liquid

17. The Norilsk Ni-Cu Deposit

18. A Model for the Norilsk Deposit
Flood basalts
Gabbro sill
Coal-bearing sediments
Sulphide
Limestones
Evaporites
Magma dissolves high concentration of sulphur
Magma saturates in sulphide due to decrease in fO2
Gabbroic magma

19. Bushveld Igneous Complex

20. Bushveld Stratigraphy
Merensky Reef
Gabbroic anorthosite
Critical Zone
Chromitite
Anorthosite
Lower Zone
Pyroxenite
Harzburgite

21. Controls on the Formation of Chromitite Layers
Magma mixing
Assimilation of silica-rich sediments

22. Merensky Reef Anorthosite Merensky Reef Chromite
Pyrrhotite + PGE minerals
Chromite

23. The Role of Convection, Crystal Settling and Repeated Magma Injection in the Bushveld

24. A Model for the Emplacement of the Bushveld Complex