云南六苴砂岩型铜矿床地球化学异常模式  

Geochemical anomaly pattern of Liuju sandstone-type copper deposit in Yunnan Province

作　　者：吴鹏[1] 韩润生[1] 李静[1] 李瑞龙 李路乔 郭学兵 苏继泉 

机构地区：[1]昆明理工大学国土资源工程学院 [2]云南楚雄矿冶股份有限公司,云南楚雄675400

出　　处：《地球化学》2008年第5期488-498,共11页Geochimica

基　　金：国家危机矿山接替资源勘查项目(200453001);教育部新世纪优秀人才支持计划项目(NCET-04-917)

摘　　要：云南六苴铜矿床是楚雄陆相红层盆地砂(页)岩型铜矿的典型代表。矿体(平均品位1.34%)赋存于K2ml1中紫色砂岩与浅色砂岩交互带,从紫色砂岩到浅色砂岩,依次呈现赤铁矿、辉铜矿、斑铜矿、黄铜矿、黄铁矿水平分带。采集9个钻孔岩芯样品,分析其主元素与微量元素地球化学异常特征,指示成矿元素组合为Cu-Ag-As-Sb-Hg。K2ml1中铜矿体,从上至下具有V-Ni→Cu-Ag-Hg-(As-Sb)→Pb-(Zn)-V-(Ni)垂向分带;由西(全紫带)至东(全浅带)具有Sb→Hg→V→Cu-As-Sb→Ag-Co-Ni→Pb→Zn横向分带。通过不同剖面地球化学异常特征对比,建立矿床的地球化学异常模式:Co-Ni-V组合异常位于矿体上方,Pb-Zn组合异常位于矿体下方,矿体处元素组合异常为Cu-Ag-As-Sb-Hg。出现Cu-Ag-As-Sb-Hg组合异常,Cu/Ag>315、Cu/(Pb+Zn)>320、Cu/(As+Sb+Hg)为1000～5800时,矿体较富,品位稳定;出现Pb-Zn-Co-(Ni)组合异常,Cu/Ag<105、Cu/(Pb+Zn)<7、Cu/(As+Sb+Hg)<36时无矿;出现Sb-Hg-V组合异常,Cu/(As+Sb+Hg)>5800时则无矿。Cu、Ag、As、Sb、Hg含量及元素对比值沿矿床走向从北向南降低,预示"矿化能力"减弱或矿体中心位置偏移。该地球化学异常模式为深部成矿预测提供了重要依据。The Liuju copper deposit, one of the typical sandstone-type copper deposits, is located in the Upper Cretaceous continental sandstone basin of Chuxiong, Yunnan Province, China. Ore bodies （average grade： Cu 1.34% ） are located in the interface between purple bed and grey bed in K2ml1. From purple bed to grey bed, the ore mineral horizontal zonality is hematite, chalcocite, bornite, chalcopyrite and pyrite. Based on geochemical data of 9 drills in this deposit, the features of major and trace elements show that the ore-forming element association is Cu-Ag-As-Sb-Hg. The axial zonality of indicator elements in K2ml1 from top to bottom is V-Ni → Cu-Ag-Hg- （As-Sb） →Pb-（Zn）-V-（Ni） and the lateral zoning from purple belt to grey belt is Sb → Hg → V → Cu-As-Sb Ag-Co-Ni → Pb → Zn. By different strata contrasted, it verifies the distribution features of geochemical anomaly. On the basis of this method, it has established the geochemical anomaly pattern, that is, anomaly of Co, Ni, and V appears above ore bodies, anomaly of Pb and Zn under ore bodies. Anomaly of Cu, Ag, As, Sb, Hg and ratio of Cu/Ag 〉 315, Cu/（Pb＋Zn） 〉 320, Cu/（As＋Sb＋Hg） 1000-5800 are concomitant with rich ore bodies; anomaly of Pb, Zn, Co, （Ni） and Cu/Ag 〈 105, Cu/（Pb ＋ Zn） 〈 7, Cu/（As ＋ Sb ＋ Hg） 〈 36 implies barren;the presence of Sb, Hg, V and Cu/（As ＋Sb ＋Hg）〉 5800 indicates barren. The contents of Cu, Ag, As, Sb, Hg and the ratio of dual elements reduce longitudinally, and it shows that copper mineralization becomes weaker or the position of the ore body is displaced. The pattern is important foundation for the depth oreorming prognosis.

关 键 词：地球化学异常模式 砂岩铜矿床 六苴 云南省 

分 类 号：P595[天文地球—地球化学]