关键词: 夏日哈木铜镍矿床, 岩浆铜镍硫化物矿床, 志留纪—泥盆纪岩体, 成矿规律, 找矿方向, 东昆仑成矿带

Abstract: The East Kunlun Metallogenic Belt (EKMB) is an important Au-Cu-Co-Ni-Fe-Pb-Zn and other polymetallic metallogenic belts in China. The discovery of the Xiarihamu super-large Ni deposit in the summer of 2011 made East Kunlun become an important Cu-Ni resource base in China. After years of exploration, great breakthroughs have been made in the prospecting of Cu-Ni deposits in the EKMB, and a number of mafic-ultramafic complexes with great prospecting potential have been discovered successively, such as Shitoukengde, Akechukesai, Langmuri and Gayahe intrusions. Based on the researches in recent years, the metallogenic regularity and characteristics of the magmatic Cu-Ni sulfide deposits in the EKMB are preliminarily summarized, and the prospecting target for the next step is pointed out. Main understandings are as follows: At least four stages of Cu-Ni-Co-(PGE) metallogenesis with different intensities occurred in the EKMB, i.e., Cambrian-Ordovician (535-445 Ma), Silurian-Devonian (440-394 Ma), Permian-Early Triassic (271-239 Ma) and Late Triassic (233-208 Ma), among which the Silurian-Devonian has the largest number of intrusions and the highest mineralization rate, and produces the largest number and scale of ore deposits, while other stages have less number of intrusions, smaller scale and weaker mineralization. Different from other ore-forming plutons scattered throughout the EKMB, the Silurian-Devonian intrusions are strictly distributed in the north of the Central Kunlun fault, and most of them occur in the Central Kunlun belt with significant clustering. They have significant metallogenic specialization with the most important ore-bearing rocks belonging to ultramafic rocks enriching in chrysolite and orthopyroxene. The primary magma is derived from the large proportion of partial melting of the asthenospheric mantle, and crustal contamination is one of the most important key factors of sulfide saturation. The Silurian-Devonian intrusions have the greatest prospecting potential, mainly distributed in the Central Kunlun belt, which is the main prospecting target and area for future prospecting and exploration. The intrusions of other stages have less prospecting potential, but the Cu-(PGE) ore-bearing of Cambrian-Ordovician intrusions still need to be further evaluated.

Key words: Xiarihamu Cu-Ni deposit; magmatic Cu-Ni sulfide deposit, Silurian-Devonian intrusions, metallogenic regularity, prospecting target, East Kunlun metallogenic belt