藏南姐纳各普金锑矿床控矿因素及找矿标志

Prospecting Indicators and Ore-controlling Factors of Jienagepu Gold-antimony Deposit in South Tibet

姐纳各普金锑矿位于藏南拆离系金锑成矿带东段,共发育12条金锑矿（化）体,长50~240 m,厚0.34~8.83 m,均呈脉状发育于下侏罗统陆热组地层,受构造控制明显。矿石类型分为热液脉型和蚀变岩型2类,热液脉型矿石主要为含辉锑矿的石英-方解石脉和含明金的石英脉,蚀变岩型矿石为角砾状蚀变板岩和蚀变中—基性岩体。在野外地质调查的基础上,对矿区地质特征、矿化特征、矿床成因进行了分析,并分别从地层、构造2个方面对控矿因素进行了详细讨论,结果表明：1邻区日当组、维美组地层Au、Sb丰度较高,可能为矿床的矿源层;2早期中—基性岩体为成矿提供了不可忽略的物质来源,晚期中—酸性岩体为成矿提供了足够的动力来源,可认为区内矿床为浅成低温热液型金锑矿床。在上述分析的基础上,系统总结了区内找矿标志,分别为构造与化探异常组合标志、物探异常标志、围岩蚀变组合标志以及Au-As-Sb组合标志。上述研究成果对于区内进一步开展找矿勘探工作及区域金锑矿成矿理论研究具有一定的参考价值。

The Jienagepu gold-antimony deposit is founded recently,which is located in the east antimony and gold metallogenic belt of southern Tibet detachment system. The Jienagepu gold-antimony deposit has 12 ore-bodies,which are occurred as veins-type, they are developed in the jurassic continental heat group formation and mainly controlled by faults significantly. They are 50 - 240 m long,0.34 -8. 83 m thick. The ore-types are divided into hydrothermal vein-type and altered rock-type, hydrothermal vein-type ore mainly contains stibnite quartz-calcite veins and gold quartz veins;altered rock-type ore is brecciated structure latered slate and alteration of intermediate-basic rock mass. Based on filed geological investigation and systematic study of geological background in the mining area,the geological characteristics, mineralization characteristics and mineral deposits genesis in the mining area are analyzed in depth, the ore-controlling factors in the mining area are also discussed from the aspects of strata and tectonic, the results show that： （1）the Ridang and Weimei stratum besides the mining area contain a large number of Au and Sb ,which maybe the source of Jienagepu gold-antimony deposit;（2）in the early period,the intermedi- ate-basic rock mass provide the ore-forming materials sources that cannot be ignored, in the late period, the intermediate-acidic rock mass provide the ore-forming enough power sources, which indicated that the deposits in the mining area are hypabyssal hydrothermal-type gold-antimony deposit with tow temperature. Based on the above analysis results, the prospecting indicators of the mining area are summarized systematically, they are structure and geochemical anomalies combination indicators, geophysical anomalies indicators,wall rock alteration combination indicators and Au-As-Sb combination indicators. The research results in this paper can provide reference for the further prospecting exploration work and the research of regional gold-antimony metallogenic theory.