云南普朗斑岩型铜矿成矿岩体的基本特征

普朗斑岩型铜矿是格咱地区印支期斑岩型铜矿的典型代表,产于义敦构造-岩浆带南端的复式岩体。复式岩体为浅成-超浅成的中酸性斑(玢)岩体,可划分为3个侵入阶段,最早为石英闪长玢岩,中期为石英二长斑岩,晚期为花岗闪长斑岩。岩石地球化学特征表明,岩石富集Ba、La、Rb、Sr、K和亲铜元素Cu、Pb,亲铁元素Mo、Ni,亏损Nb、Zr、Hf、Ti。斑(玢)岩与岛弧花岗岩的岩石系列相同,属钙碱性岩系,成因类型一致,属I型花岗岩。普朗斑岩型铜矿床主要产于印支期的中酸性斑(玢)岩体,成矿作用受岩浆岩、侵位地层、热液运移、热液蚀变作用和构造空间的控制,其印支期构造-岩浆-热液之间的耦合,共同形成了斑岩成矿系统。

The characteristics of metallogenic rocks in the Pulang porphyry copper deposit of Yunnan Province

The Pulang porphyry copper deposit is a typical Indo-Chinese porphyry copper deposit in Zhongdian area,hosted in southern composite body of the Yidun structural—magmatic belt.The composite rock body is a hypabyssal-ultrahypabyssal intermediate-acid porphyry(porphyrite) body,which can be divided into three invasion stages,i.e.,quartz diorite porphyrite,quartz monzonite porphyry,and granodiorite—porphyry.Geochemical characteristics show that the rocks are enriched with Ba,La,Rb,Sr,K,chalcophile elements Cu,Pb,and siderophile elements Mo,Ni,and are depleted in Nb,Zr,Hf and Ti.Porphyry(porphyrite) is the same as the rock series of granite island,belonging to calc—alkaline suite,and their genetic types are also similar to each other,belonging to I-type granite.The ore bodies are controlled by structures.The porphyry copper deposit mainly occurs in the Indo-Chinese intermediate-acid porphyry(porphyrite),and the mineralization was controlled by such factors as magmatic rocks,emplacement formation,uranium migration,hydrothermal alteration and structural space,which jointly constituted a porphyry metallogenic system characterized by the structural—magmatic—hydrothermal coupling in Indo-Chinese period.