云南香格里拉春都斑岩铜矿区围岩蚀变及矿化特征

Features of alteration and mineralization in the Chundu porphyry copper deposit,Xianggelila,Yunnan Province

春都斑岩铜矿床地处著名的印支期中甸-义敦岛弧成矿带南端。矿区出露闪长玢岩-花岗闪长斑岩复式岩体,成矿岩体为印支晚期的花岗闪长斑岩。围绕成矿岩体,围岩蚀变强烈,蚀变分带明显,由中心向外,依次出现硅化钾化带→绢英岩化带→硅化带→硅化黑云母化带→青磐岩化带→绢云母化及泥化带。区内蚀变与矿化关系密切,蚀变类型决定矿化程度,蚀变带的分布控制矿体产状。因此,围岩蚀变特征的研究将为矿区进一步找矿提供重要依据。

The Chundu porphyry copper deposit lies in the southernmost famous Zhongdian-Yidun island arc of the Indosinian Orogeny. There are cropping-out of multi-legs rock mass composed of diorite porphyrite and granodiorite-porphyly in the orefield. The granodiorite-porphyry is granodiorite -porphyry metallogenic rock mass in the orefield. There are fierce alteration of wall rock and visible zonality of alteration in the orefield sun＇ounding the metallogenic rock mass. There exist kali silicification zone→sericitolite zone^silicification and biotitization zone→silification zone→propylitization zone→ sericitization and argillization zone ,from centre to outside surrounding the metallogenic rock mass. The alteration is closely related with mineralization in this area. The degree of mineralization depends on the types of alteration and the occurrence of orebody is controlled by the distribution of alteration zones. So the study of alteration of wall rock will provide important evidence for further prospecting in the orefield.