秘鲁马尔科纳铁矿区北部TA-02勘查区铜多金属矿地质特征及成矿类型

Geological characteristics and type of Cu-polymetallic deposit in the property TA-02 of the North Marcona Fe ore district,Peru

秘鲁马尔科纳(Marcona)铁矿区北部TA-02勘查区蕴含丰富的铜矿和铁矿资源,并伴生锌、钴等矿产资源。TA-02勘查区处于环太平洋构造-岩浆活动带的东侧,西南部发育有圣尼古拉斯(San Nicolás)岩基,胡斯塔(Justa)断裂控制了区内的铁、铜矿化及阳起石化蚀变带,是勘查区内(铁)铜矿体的主要控矿构造;胡斯塔断裂内常充填磁铁矿体、铜矿体及不同种类的脉岩,矿体形态以脉状为主;矿石中含铜矿物主要为黄铜矿,伴生/共生金属矿物主要为磁铁矿、赤铁矿、钴矿物、闪锌矿等,铜矿化与铁矿化具有高度的一致性,共/伴生关系密切,二者呈正相关关系,因此铜矿区呈现较高的磁异常;此外,矿体穿切地层,赋矿围岩无专属性,围岩蚀变以阳起石化蚀变为特征。研究认为,TA-02勘查区铜多金属矿属于IOCG型(氧化铁型铜-金)矿床。

The property TA-02 is located at east side of the Pacific Rim tectonic-magmatic active belt and San Nicolas batholith occurs at its Southwest part.It is abundant with Fe,Cu and the Zn,Co and other by-product mineral resources.The fault Justa controls Fe,Cu mineralization and actinolite alteration zone in the property thus is the main ore-control structure.In the fractured zone occur magnetite ore bodies,Cu ore bodies and different dykes.The ore bodies are generally vein-like.Chalcopyrte is the main Cu mineral,magnetite,hematite,Co minerals,Sphalerite etc.the companied and associated minerals.Fe mineralization is highly coincided with Cu mineralization,i.e.the Fe ore and Cu ore are always accompanied or closely associated,positively correlated.Cu ore shows relatively high magnetic anomaly.Ore bodies cut strata without special attribute to any lithology and rock unit.The wall rock alteration is characterized by actinolite.Polymetallic ore in the property belongs to IOCG type.