摘要
本文根据该铅锌矿带成矿地质背景,结合元素地球化学特征和稳定同位素资料,研究了不同类型矿床在时间、空间上的分布规律和成矿物质来源,并指出了找矿方向矿带内铅锌矿床可划分为四个系列、八个成因类型。矿带跨越三江褶皱系、松潘-甘孜褶皱系和扬子准地台三个I级大地构造单元,呈南北向狭长条带状,受壳下深部构造的控制。金属在地壳中的再分配,主要与南北向导矿构造有关。容矿构造以圈闭一半圈闭构造为主要。铅锌主要来自:(1)地幔源:(2)赋矿地层或岛弧型火山岩(壳源或壳幔混合源)。成矿在时间上与地壳的多旋回构造运动密切相关。成矿期以喜马拉雅期为主,燕山期、印支期和加里东期次要。对矿带内的铅锌矿床划分为与喜马拉雅期中酸(偏碱)性幔源岩浆小侵入体有关的沉积改造型、混合源热液型、斑岩型、接触型和热液脉型等不同类型,并建立其成矿复合模式。
According to the metallogenic geological setting of the Lead-zinc ore zone, combined with the element geochemical characteristics and stable isoto-pie data, this paper studied the distributed regularity in time and space, and the metallogenic material sources on different types of ore deposits, mean-while, also pointed out the directions of prospecting. The Pb-Zn ore deposits in ore zone can be divided into four series and eight origin types. This ore zone which strides across three first-order geo-tectonic units of Sanjiang, Songpan-Ganzi fold systems and Yangtzi parap-latform, with the appearance of narrow strips running N-S was controlled by the subcrustal deep-seated structures. The redistribution of metal in crust is mainly related to the ore-transmissing structures of N-S direction. The ore-hosting structures are largely the trapped-semitrapped ones. Lead and Zinc came from:(1)the mantle-derived ones;(2) ore-bearing strata or island-arc type vocanics(crust-or crust-mantle-derived ones). The ore-forming process were closely relevant to the crustal polycyelic movements in time. The metalloge-nic epoches were principally the Himalayan epoch, with Yanshan,indosinian and Caledonian periods being subordinate. This paper divided the Pb-Zn de-posits in this ore zone into the sedimento-reformation type relevant to small intrusions of intermediate-acidic(meta-alkali)mantle-derived magma of Hima-layan period, mixed-derived hydrothermal type, porphyry type, contact type and hydrothermal vein type, and put forward its metallogenic composite mo-del.
出处
《云南地质》
1991年第2期119-144,共26页
Yunnan Geology
