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鲁春铜铅锌矿床位于中咱-中甸板块和昌都-思茅板块之间的金沙江构造带中部,矿体长约3 km,厚度在1.06～16.35 m之间。其赋矿围岩为火山沉积岩系,容矿构造为印支期逆断层。鲁春铜铅锌矿床矿石中硫化物的δ34S值变化于3.5‰～6.8‰之间,硫化物的206Pb/204Pb比值为18.554～18.656,207Pb/204Pb比值为15.662～15.752,208Pb/204Pb比值为38.801～39.009。石英流体包裹体的HO182δO值变化范围为2.74‰～1.25‰,δDV-SMOW变化范围为107‰～123‰。鲁春铜铅锌矿床的硫铅氢氧同位素分析结果表明,该矿床成矿物质来源于地幔,部分来源于岩浆,在成矿流体上升过程中,有壳源物质的加入。早二叠世晚期金沙江洋盆向西俯冲形成了一系列逆断层,同时导致下地壳部分熔融,引发大规模的火山岩浆作用。在晚三叠世早期,构造背景由挤压环境到伸展环境的转折期,这些逆断层具有张性的特点,为后期的成矿热液提供了有利的容矿构造。上升的岩浆为地幔楔内的成矿流体提供了通道。岩浆内的部分成矿流体进入白茫雪山花岗闪长岩体附近的逆断层富集成矿。
The Luchuang Cu-Pb-Zn deposit is located in the middle part of the Jinshajiang structural belt between Zhong-Zan-Zhongdian Member and Qamdo-Simao Plate. The ore body is about 3 km in length with a thickness of 1.06-16.35 m. The ore-hosting rock is volcanic sedimentary rock series, and the ore-hosting structure is Indosinian reverse fault. The δ34S values of sulphides in the Luchuan Cu-Pb-Zn ore deposit varied from 3.5 ‰ to 6.8 ‰, and the 206Pb / 204Pb ratios of the sulphides ranged from 18.554 to 18.656 and from 207Pb / 204Pb to 15.662 to 15.752, and the 208Pb / 204Pb ratios were 38.801 ~ 39.009. The range of HO182δO value of quartz fluid inclusions ranged from 2.74 ‰ to 1.25 ‰, and the δDV-SMOW ranged from 107 ‰ to 123 ‰. The results of sulfur, lead and hydrogen isotope analysis of the Luchuan-Cu-Pb-Zn ore deposit show that the ore-forming material of the deposit originated from the mantle and partly from magma. During the process of ore-forming fluid ascending, the source material was added. The Lower Permian Late Jinshanjiang basin subducted westward to form a series of reverse faults, which led to the partial melting of the lower crust, triggering large-scale volcanic magmatism. In the late Late Triassic, the tectonic setting changed from the crusting environment to the extensional environment. These reverse faults have the characteristics of tension, which provide a favorable ore-hosting structure for the ore-forming hydrothermal fluids in the later period. Ascending magma provides access to the ore-forming fluid within the mantle wedge. Some of the ore-forming fluids in the magma enter the reverse fault enrichment and mineralization near the Baiyue Xueshan granodiorite body.