印度尼西亚苏门答腊岛马塔比（Martabe）浅成低温热液型金-银矿床的地质特征与找矿标志

马塔比矿床位于印度尼西亚北苏门答腊省，是印度尼西亚近年确认的一处世界级高硫浅成低温热液型金-银矿床。文章在梳理前人研究的基础上，对其成矿地质特征与找矿标志进行了总结，以丰富该类型矿床实例，指导找矿实践。该矿床金银矿化呈现典型的高硫型浅成低温热液系统蚀变分带特征，由内而外依次发育硅化带、高级泥化带、泥化带、青磐岩化带。赋矿英安岩的锆石U-Pb 定年结果为（3.8±0.5）Ma，热液变质成因明矾石的Ar-Ar 坪年龄分别为（3.3±0.11）Ma 和（2.14±0.10）Ma，表明成岩与成矿间隔时间较短，且可能存在两期高级泥化蚀变作用。成矿作用既有岩浆热液又有大气水的参与，后期地表风化作用使金和银进一步富集。马塔比矿床具有高硫型浅成低温热液矿床的典型特征，总结其找矿标志包括构造环境标志、岩性标志、蚀变标志和化探标志。

Geological Features and Prospecting Indicators of Martabe Epithermal Au-Ag Deposit,Sumatra,Indonesia

The Martabe deposit,located in the North Sumatra,Indonesia,is a world-class high-sulfidation epithermal Au-Ag deposit discovered in recent years.Based on a comprehensive review of previous knowledge of this deposit,this paper present a summary of its metallogenic geological features,aiming to enrich the cases of epithermal deposits and guide exploration of this type of deposits.The Martabe deposit has similar alteration zonation with typical high-sulfidation epithermal deposit,with zones such as silica,advanced argillic,argillic,and prophylitic zones from the core to the margin.Zircon U-Pb dating on ore-bearing dacite yielded an age of(3.8±0.5)Ma,while two ages of(3.3±0.1)Ma and(2.1±0.1)Ma were obtained from Ar-Ar age determination on hydrothermal alunite,indicating a brief interval between diagenesis and mineralization and two stages of advanced argillic alteration.Mineralization was associated with the interaction between magma-sourced fluid and meteoric water and further intensified by weathering and erosion following ore-forming.Martabe deposit shares characteristics with the classical high-sulfidation epithermal deposits,displaying prospecting signals in the aspects of tectonic setting,lithology,alteration,and geochemical explorations.