桐柏山南坡金矿床(点)地质特征、成因及找矿前景

Geological Characteristics,Genesis and Prospecting Potential of Gold Deposit(Point)in Southern Slope of Tongbai Mountain

桐柏山南坡位于武当—桐柏—大别成矿带中段,是金多金属矿成矿有利地段,但该区金矿综合研究工作比较薄弱。重点分析该区金矿成矿地质条件、矿化类型、成矿时代、空间分布、成矿物质来源等特征,探讨矿床成因及找矿前景。分析认为,桐柏山南坡金矿受构造—岩浆活动制约,成矿时代为燕山早期(143.1~128.2 Ma),成矿物质主要来源于与中生代花岗岩有关的壳幔混合源,成矿流体为岩浆水与大气降水的混合流体,属中—低温浅成岩浆热液型矿床。桐柏山南坡可圈定新城—黄陂断裂带、马鞍山—青苔断裂带及新市—太山庙断裂带3个成矿远景区,新城—黄陂断裂带南西以金(银)矿为主,浅部金(银)矿床(点)密集分布,深部铅锌矿、钼矿具较好成矿前景;该断裂北东以铅锌矿、钼矿为主。研究成果可为区域金多金属矿找矿勘查工作提供有益的地质依据。

The south slope of Tongbai Mountain is located in the middle of Tongbai-Dabie Mesozoic metallogenic belt,which is a favorable area for gold polymetallic mineralization.However,the comprehensive research on gold deposits in this area is relatively weak.The paper focuses on the analysis of gold mineralization geological conditions,mineralization types,mineralization age,spatial distribution,metallogenic material sources and other characteristics,and discusses the genesis and prospecting potential.The study shows that the mineralization age of the deposits is early Yanshanian(143.1~128.2 Ma).The ore-forming materials are mainly derived from the crust-mantle mixing source related to Mesozoic granite,and the ore-forming fluid is derived from the mixing source of magmatic water and atmospheric precipitation.It is mainly restricted by tectonic-magmatic activities,and belongs to medium-low temperature epithermal magmatic deposit.The south slope of Tongbai Mountain can delineate three metallogenic prospect areas:Xincheng-Huangpi fault zone,Ma'anshan-Qingtai fault zone and Xinshi-Taishanmiao fault zone.The southwest of Xincheng-Huangpi fault zone is dominated by gold(silver)deposits,and the shallow gold(silver)deposits(occurrences)are densely distributed.Deep lead-zinc and molybdenum deposits have good metallogenic prospects.The fault is mainly lead-zinc and molybdenum ore in the northeast.The research results can provide useful geological basis for regional gold prospecting and exploration.