Re-Os and Pt-Os isotopic systematics of the Jinchuan Ni-Cu-PGE ore deposit,China

摘要

The Jinchuan ultramafic intrusion in northwest China has reserves of nearly 500 million tones of Ni-Cu sulfide ore (grading 1.2% Ni and 0.7% Cu) and is ranked the world's third largest magmatic Ni-Cu sulfide deposit. The deposit is also one of the largest PGE deposits of China.The Jinchuan intrusion is located in the Longshoushan Dome, a fault-bounded, NW-striking terrane between the Alax massif (the westernmost part of the North China Craton) to the north and the northern Qilian-Qinling Orogenic Belt to the south. It intruded Paleoproterozoic migmatite, gneiss, and serpentine marble of the Longshoushan Group and is cut by dolerite dykes. The intrusion is about 6500 m long and 20 m to > 500 m wide. The intrusion and its sulfide ores are divided into four mining areas (from west to east, Ⅲ, Ⅰ, Ⅱ and Ⅳ) by NE-trending faults.