http://www.sciencedirect.com/science/article/pii/S1674987111000429

The three most crucial factors for the formation of large and super-large magmatic sulfidedeposits are: (1) a large volume of mantle-derived mafic-ultramafic magmas that participated in theformation of the deposits; (2) fractional crystallization and crustal contamination, particularly the inputof sulfur from crustal rocks, resulting in sulfide immiscibility and segregation; and (3) the timing ofsulfide concentration in the intrusion. The super-large magmatic Ni-Cu sulfide deposits around the worldhave been found in small mafic-ultramafic intrusions, except for the Sudbury deposit. Studies in the pastdecade indicated that the intrusions hosting large and super-large magmatic sulfide deposits occur inmagma conduits, such as those in China, including Jinchuan (Gansu), Yangliuping (Sichuan), Kalatongke(Xinjiang), and Hongqiling (Jilin). Magma conduits as open magma systems provide a perfect environmentfor extensive concentration of immiscible sulfide melts, which have been found to occur along deepregional faults. The origin of many mantle-derived magmas is closely associated with mantle plumes,intracontinental rifts, or post-collisional extension. Although it has been confirmed that sulfide immiscibilityresults from crustal contamination, grades of sulfide ores are also related to the nature of theparental magmas, the ratio between silicate magma and immiscible sulfide melt, the reaction betweenthe sulfide melts and newly injected silicate magmas, and fractionation of the sulfide melt. The field relationshipsof the ore-bearing intrusion and the sulfide ore body are controlled by the geological features ofthe wall rocks. In this paper, we attempt to demonstrate the general characteristics, formation mechanism,tectonic settings, and indicators of magmatic sulfide deposits occurring in magmatic conduits whichwould provide guidelines for further exploration.