论永梅会多层、多类型成矿集中区大型铜、金、银、锡矿床成矿远景

近10多年来东南沿海找矿具突破性意义的一批矿床中，有5个各具特色的矿床及与之相类似的一批矿床（点）和矿化层位，集中分布在闽粤赣三省交界处面积约为8万km2的永定一梅县－会昌地区（简称永梅会地区），构成一成矿集中区．其特点是矿床集中且规模大、埋藏浅、多类型和多层性。该区处于不同构造单元的交接、叠置地带，自晋宁期至晚燕山期漫长的地质历史为形成多层、多类型矿床提供了良好的成矿环境；频繁的火山一侵入活动揭示了壳幔分离、地幔物质多次注入、地壳物质多次循环，特别是石炭纪以来（C1、J1、K1）三次双峰式火山活动所反映的位张环境，造就了本区成矿元素多、丰度高的地球化学场和构造应力环境；可能存在的地幔热流柱对地壳的作用是构成矿床集中的深部构造因素；区内石炭系岩相古地理特征显示本区具有与长江中下游地区石炭系铜矿含矿层位相当的合矿层位；本区中等剥蚀程度有利于寻找火山根部带或基底中的矿床。在分析该区上述成矿远景基础上，提出了该区有可能成为我国南方继德兴之后及维长江中下游地区之后的另一个铜、多金属成矿区。

ON MINERALIZATION PERSPECTIVE OF LARGESCALE COPPER,SILVER AND TIN DEPOSITS IN YONG' AN-MEIXIAN-HUICHANG MULTI-HORI-ZON AND MULTI-GENESIS MINERALIZATION-CONCENTRATED REGION

Among a lot of new discovered mineral deposits which have a breakthlugh significance in the ore prospecting in the southeastern coastal area during recent 10 years, 5 different representative ore deposits, namely Zijingshan copper deposit, Yanbei tin deposit, Songxi stibium - silverdeposit, Yushui copper deposit and Shuangqishan gold deposit, along with numhers of similarore deposits(ore occurrences) and mineralization horizons, are densely distributed in Yong anMeixian - Huichang region(Yongmeihui region for short)with an area of about 80000 km2 atthe juncture of Fujian, Guangdong and Jiangxi provinces, forming a mineralization - concentrated region. The deposits in the region are characterized by large scale(or limited scale but extremely pay ore), limited buried depth, multi - horizon and multi - genesis mineralization. Theregion is located in the joint and superimposed zone of different tectonic units, it underwent acomplicated crustal evolution history involving collision, tension after collision and spreadingbreakup of continental blocks during Jinning period to Yanshan period, thus providing afavourable environment for mineralization of multi - horizon and multi - genesis deposits. Thefrequent volcanic - intrusive activities implied the crust - mantle differentiation, multiple pouring of the mantle material and mutiple circulation of the crustal material, especially the tensionalstress environment reflected by 3 bimodal volcanic activities since Carboniferous(C1, J1, K1 ) created a multi - element and highly abundant geochemical field. The effect of the possible mantleflux plume on the crust might serve as a deep - seated structure factor which caused the concentration of ore deposits. The Carboniferous lithofacies and paleogeography of the region show thatthe ore - bearing horizons existed in the region can be compared with the Carboniferous copper- bearing horizons developed in the middle - lower Yangtze area.The medium denudation of the region is favourable to prospecting ore depostits emplaccedin the root zones of volcanoes and basement strata. Based on the analysis of above - mentionedmineralization perspective of the region, it is suggested that the Yongmeihui region is possible tobecome another copper - polymetal mineralized area in South China after Dexing copper deposits and ore deposit - concentrated area in the middle - lower Yangtze valley.