秘鲁Pachagon铜矿床岩石地球化学特征及成因  

Lithogeochemical characteristics and origin of the Pachagon copper deposit in Peru

作　　者：袁莹 刘方方[2] 薛培 彭晓明 YUAN Ying;LIU Fang-fang;XUE Pei;PENG Xiao-ming(Sinotech Mineral Exploration Co.,Ltd.,Beijing 100012;China Gold Group Geological Corporation,Beijing 100012;Wanbao Mining LTD.,beijing 100012)

机构地区：[1]中色地科矿产勘查股份有限公司,北京100012 [2]中国黄金集团地质有限公司,北京100012 [3]万宝矿产有限公司,北京100012

出　　处：《矿产勘查》2019年第10期2691-2700,共10页Mineral Exploration

摘　　要：帕加贡铜矿床位于秘鲁北部重要斑岩成矿带上,文章就该区岩相学、矿相学、岩石化学及稀土微量元素地球化学等方面进行了研究,并依据宏观地质产状、矿石矿物组成、结构构造及生成顺序、主微量元素组成特征等,总结了矿床成因,推测矿区成矿模型。该区砂岩中的构造破碎带是矿体的主要产出部位,为受构造控制的次生铜富集带,但有证据显示其成矿与深部岩体存在一定关系:(1)矿石镜下见热液成因黄铜矿及半自形中高温矿物晶出;(2)铜的富集过程伴随不相容元素含量的递增;(3)矿物组合由浅至深辉铜矿减少,黄铜矿、磁黄铁矿增加,且随深度增加,硅化逐渐增强。综合判断矿区成矿类型:浅部为受构造控制的次生富集带铜矿,深部为与岩体有关的斑岩型铜矿床。The Pachagon copper deposit is located on the famous porphyry belt in thenorthern Peru.Based on geological occurrence,ore minerals composition,fabric and their formation sequence,geochemical characteristics of main and trace elements,the paper summarized the genetic type of the deposit. The ore body occurs in the structural fracture belt of sandstone,resulted in the formation of a secondary enrichment zone which is controlled by structure. Mineralization is related to deep rock mass with the following evidences. (1) Mineral paragenesis shows a intermediate hydrothermal stage with middle to high temperature mineral;(2) Enrichment of Cu accompanied by the increase of incompatible elements;(3) Chalcocite decreased while chalcopyrite and pyrrhotite increased and silisification intensified with depth. The shallow ore deposit is supergene Cu controlled by structure while the deep deposit is hypogene porphyry deposit.

关 键 词：秘鲁 铜矿床 地球化学 构造蚀变岩 热液矿床 

分 类 号：P618.41[天文地球—矿床学]