曲仁盆地北缘铅锌硫化物矿床关键控矿因素及成矿系统

姚翠霞^{1, 2}，张术根^{1, 2}，王 超^{1, 2}

(1. 中南大学 有色金属成矿预测教育部重点实验室，长沙 410083；
2. 中南大学 地球科学与信息物理学院，长沙 410083)

摘 要：曲仁中生代断陷盆地北缘地区出露上古生界碳酸盐岩建造，其内已发现超大型凡口铅锌矿床，并在凡口矿区西侧见杨柳塘、红珠冲等铅锌矿床、西岗寨、罗村黄铁矿矿床等，东侧见铁屎岭等铁矿点。通过综合分析研究区硫化物矿床地质矿化特征、区域水文地球化学环境和成矿流体驱动、传输和汇聚机制，融合递进成矿论与成矿系统论思想，认为研究区自元古宙主要经历了三大构造演化阶段及多种构造体制的转化，导致了多期构造热事件和岩浆侵入活动发生，为盆地北缘金属元素的大规模富集成矿创造了条件。按成矿时间先后将凡口式铅锌硫化物成矿划分为两个成矿系统，即印支期包括压缩驱动、近东西向褶皱、层间滑动构造、沉积成岩期黄铁矿和地层硫储体、碳酸盐岩含水层等关键控矿因素的黄铁矿热液成矿系统；燕山早期包括热膨胀驱动、NE、NW向断裂构造、基底碎屑岩含水层、壳源重熔型花岗质岩浆、古地热异常等关键控矿因素的铅锌热液成矿系统。凡口式铅锌硫化物矿床是这两个成矿系统在时间和空间上的继承、叠加和改造的结果。

关键词：曲仁盆地北缘；铅锌硫化物矿床；关键控矿因素；成矿系统

Key ore-controlling factors and metallogenic system of lead-zinc sulfide deposits in northern margin of Quren basin

YAO Cui-xia^{1, 2}, ZHANG Shu-gen^{1, 2}, WANG Chao^{1, 2}

(1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education,
Central South University, Changsha 410083, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China)

Abstract:The northern margin of Quren Mesozoic faulted basin outcrops Paleozoic carbonate formation, in which Fankou large lead-zinc deposit was discovered. Meanwhile, Yangliutang, Hongzhucong lead-zinc deposits and Xigangzai, Luocun pyrite deposits were discovered in the westward of Fankou mine, and Tieshiling iron points were discovered in the eastward of Fankou mine. Through comprehensively analyzing the geological and mineralization characteristics of these sulphide deposits in this area, the regional hydrogeochemical environment, forming fluid driving, transmission and aggregation mechanism, by fusing progressive mineralization and metallogenic system theory, the study suggests that this research area had mainly undergone three large tectonic evolution stages since Proterozoic and the conversion of a variety of tectonic regime. All those resulted in the multi-period structure thermal events and magma intrusion activities, and created the conditions of the metal elements enrichment and mineralization in large scale. Fankou-type lead-zinc sulfide mineralization in this area can be chronologically divided into two metallogenic systems, one of which is Indosinian pyrite hydrothermal mineralization system controlled by key factors of compression driver, the EW fold, interlayer sliding structure, sedimentary diagenetic pyrite and sulfur storage body in carbonate Aquifer. The other one is Early Yanshanian lead-zinc sulfide hydrothermal mineralization system controlled by key factors of thermal expansion driver, NE, NW faults, clastic basement aquifer, crust remelting type granitic magmatism and ancient geothermal anomaly. Fankou-type lead-zinc sulfide deposit is formed because of inheritance, superimposition and alteration of combined the two metallogenic systems.

Key words:northern margin of Quren basin; lead-zinc sulfide deposit; key ore-controlling factors; metallogenic system