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在云南个旧地区发育大量与成矿时空密切相关的侵入岩。个旧东区的老厂-卡房花岗质岩体为一隐伏的花岗岩体,侵入于三叠统个旧组碳酸盐地层中,岩性主要为中细粒黑云母花岗岩,是个旧地区与成矿关系最为密切的花岗岩体之一。岩石的ACNK值大多在1.0以上,属于高钾钙碱性系列岩石;U、Th含量较高,应归属于HHP花岗岩;岩石类型属于S型花岗岩,但经历了高度的分异和演化;Rb/Sn-Rb/Ba与CaO/Na2O-Al2O3/TiO2图解均暗示岩石的源区性质为由粘土岩所派生的岩浆。锆石LA-ICP-MS定年结果表明,老厂-卡房岩体形成于85±0.85Ma,相当于晚白垩世。根据区域地质和花岗岩的地球化学特征,暗示个旧地区燕山晚期处于伸展构造背景。
A large number of intrusive rocks are developed in Gejiu area, Yunnan Province, which are closely related to the ore-forming time and space. The old plant of Gejiu Eastern Region-Castile granitic massif is a concealed granite body that intrudes into the Triassic Gejiu Carbonate Formation. The lithology is mainly medium-fine biotite granite, which is an old region and mineralization One of the most closely related granite bodies. Most of the rocks have ACNK values above 1.0, belonging to the high-K calc-alkaline series rocks. The U and Th contents are higher and should be attributed to HHP granites. The rock types belong to S-type granites but undergo a high degree of differentiation and evolution. The Rb / The Sn-Rb / Ba and CaO / Na2O-Al2O3 / TiO2 diagrams all imply that the source nature of the rock is magma derived from clay rock. Zircon LA-ICP-MS dating results show that the old plant-wreck rock body formed at 85 ± 0.85Ma, which is equivalent to the Late Cretaceous. According to the regional geology and the geochemical characteristics of granite, it implies that Late Yanshanian in the Gejiu area is in an extensional tectonic setting.