个旧锡多金属矿区卡房玄武岩型铜矿容矿构造解析及地质意义

 云南个旧是全球最大的锡铜多金属矿区,包括马拉格、松树脚、高松、老厂和卡房5大矿田.卡房铜矿主要的矿床类型有两类:玄武岩与大理岩层间的似层状矿床和花岗岩与围岩接触带矽卡岩型矿床.关于该区的成矿作用存在多种认识,除了传统上认为与燕山期花岗岩有关外,还有海底喷流成矿和玄武岩成矿的新认识.本文选取矿区内玄武岩型铜矿为主要研究对象,对区内花岗岩和玄武岩及大理岩中的控矿构造和容矿构造的构造产状进行测量和解析,揭示容矿构造的发育规律.研究结果表明,玄武岩型铜矿床明显受南北向、东西向和北东向构造控制.以往研究工作中所忽略的北西向构造在今后的勘探部署工作中应引起足够的重视,优势容矿空间展布方位亦为上述几个方向.这一认识将为下一步接替资源的勘探指明方向,亦为建立卡房矿田玄武岩型矿床成因模型提供矿田构造方面的重要依据.

Ore-hosting Structures of Kafang Basalt Type Copper Deposit, Gejiu District of Tin Polymetallic Ore and Its Geological Implication

Gejiu tin-copper polymetallic ore deposit located in Yunnan Province is one of the largest tin ore districts in the world, comprising of Malage, Songshujiao, Gaosong, Laochang, and Kafang ore fields. There are two kinds of ore-bodies in Kafang copper deposit. One is stratiform-like ore-body, and the other is contact skarn ore-body. This deposit has been known as the Yanshanian granite-related deposit for long time, however recently some researches argue that it is a syngenetic deposit formed by marine exhalation or it is a basalt-related. The Kafang and Laochang basalt type copper deposit is selected as the main study object. In order to reveal the ore-hosting structural development patterns and its geological implication, the measurement and statistical analysis on the ore-hosting or ore-controlling structures developed in granite, basalt, and marble are studied. It shows that the basalt type copper deposit mainly controlled by the N-S direction, E-W direction, and NE trending structures, and especially the NW trending structures should be given more attention than ever before. The ore-hosting structural space is also controlled by these structures. The results will provide an important evidence for the genetic type establishment of Kafang and Laochang basalt copper deposit, and give a guide to the next exploration of ore resources.