Comparison of Jinbaoshan PGE Deposit and other Foreign PGE Deposits in Large Layered Intrusion

The Jinbaoshan Pt-Pd deposit is the largest independent Pt-Pd deposits in China at present, and the world famous PGE deposits are mainly Bushveld and Stillwater deposits. In this paper, the similarities and differences of tectonic setting, intrusion type, rock assemblages, geochemistry among Jin Baoshan, Bushveld and Stillwater deposits have been summarized. The results show that the Jinbaoshan deposit (260Ma) was occurred in the Emeishan Large Igneous Province, which is located at relatively stable tectonic environment, but its stable degree of tectonic environment is less than Bushveld (2.06Ga) that developed from craton and Stillwater (2.70Ga) from intracontinental rift, and these differences have been reflected in the scale of intrusion. Although these three intrusions are layered intrusion, the exposed area of the Jinbaoshan intusion is less than 3 km², far less than the Bushveld (65 000 km²) and Stillwater (376 km²). The rock types of the Jinbaoshan intusion is relatively simple, are mainly wehrlite and a small amount of olive pyroxenite and pyroxenite, while Bushveld and Stillwater are derived from a variety of primary magmas with thoroughly differentiation and have many rock types from ultramafic rock to mafic rocks. Compared with the Bushveld and Stillwater, the compositions of olivine and pyroxene in the Jinbaoshan vary small; On geochemistry, the rocks of the Jinbaoshan are characterized by silicon-poor and magnesium-rich. The occurrence and rock lithology of ores in the Jinbaoshan deposit are similar to the Platreef layers in Bushveld. The highest contents of PGE in the Jinbaoshan deposit is 1.5 ppm, lower than the J-M layer in Stillwater (20×10^-6), the Platreef (5×10^-6) and Merensky (5×10^-6~7×10^-6) in Bushveld. Affected by the differences in the scale of the intrusion, the degree of magmatic differentiation and liquation, the size of the Jin Baoshan deposits is far less than the Bushveld and Stillwater.