青海浪木日地区镍铂钯成矿特征

青海省都兰县浪木日地区镍铂钯矿床是东昆仑成矿带上继夏日哈木铜镍矿之后,发现的岩浆熔离型铜镍铂钯硫化物矿床。本文通过矿床地质、物探、工程工作及综合研究,总结了成矿侵入岩特征及其与镍铂钯赋存关系,认为浪木日含矿岩体呈小岩体群由东南向北西侵入金水口群片麻岩地层,这些岩体为脉状杂岩体,矿体多呈透镜体,矿化主要特征表现为:以镍为主,共伴生铜钴铂钯,其中铂钯与铜成矿关系密切。矿体多位于岩相边部与围岩接触部位,可能是围岩混染促进了硫化物饱和。浪木日矿床辉石以单斜辉石为主,不同于夏日哈木超大型镍钴矿床的辉石以斜方辉石为主。单斜辉石代表着岩浆富钙,是不利于硫化物饱和的一个因素,这可能是浪木日矿区硫化物不如夏日哈木富集的一个因素。本文研究成果对东昆仑东段铜镍铂钯找矿具有指导意义。

Metallogenic characteristics of nickel-platinum-palladium deposit in Langmuri area, Qinghai

The nickel-platinum-palladium sulfide deposit in Langmugri area, Dulan County in Qinghai Province, is a magmatic sulfide deposit discovered in the East Kunlun metallogenic belt after the discovery of the Xiarihamu giant nickel-cobalt deposit. This paper summarizes the metallogenic regularity of the deposit through a comprehensive study of geology, geophysical exploration, and engineering control. We infer that the Langmugri ore-bearing complex intrudeded into the Jinshuikou Group from southeast to northwest. Most ore bodies are on the top of the intrusions. The Pt and Pd enrichment is closely related to the Cu elements. The ore bodies are located mainly in the contact part between the edge part of lithofacies and the surrounding rock, probably because the contamination of the surrounding rock promoted sulfide saturation. The pyroxene in Langmuri area is mainly clinopyroxene; on the contrary, the pyroxene in the Xiarihamu giant Ni-Co deposit is mainly orthopyroxene. The clinopyroxene represents high calcium content in the magma, which is a factor that could hinder sulfide saturation. This may be a factor that the sulfide enrichment in the Langmuri is not as good as that of Xiarihamu deposit. This work could provide guidance for Cu-Ni-Co-PGEs prospecting in the East Kunlun metallogenic belt.