摘要
抛刀岭金矿位于长江中下游成矿带安庆—池州矿集区,累计金金属量大于22t,为池州地区首例大型金矿床。该矿床金矿体主要产在英安玢岩中,基本不伴生其他有益金属元素,为独立金矿床。通过详细的矿床地质特征描述,结合已有斑岩型金矿的成矿模式,同时利用以往对该含矿岩体U-Pb锆石定年及相关地球化学研究,综合分析认为该矿为产在早白垩纪岛弧背景下的贫铜斑岩型金矿床,同时局部矿段在成矿过程中还经历了热液叠加作用。矿体产出严格受NE向构造-岩浆岩带控制,含矿岩体出露面积小于1.0km2,属于典型的小岩体成大矿。运用"相似类比"、"矿床谱系"、"趋势外推"、"综合信息评价"等原则,指出该矿具有特大型金矿的潜质;同时,受同一NE向构造控制的乌石、白虎山及自来山等同期岩浆岩发育地区,具有与抛刀岭金矿类似的成矿条件,是未来工作的重点靶区;发育于上述同期岩浆岩之间的志留纪地层中的破碎带蚀变岩、与斑岩型矿床配套产出的低温热液多金属硫化物型矿床等,都将是外围工作的重点研究地区。
Paodaoling gold deposit is located in Anqing-Chizhou ore concentrated area of the middle-lower Yangtze River metallogenic belt.It is the first large gold deposit discovered in Chizhou area with more than 22 t gold.Paodaoling gold deposit is independent with little other economic metal elements,and develop mainly in dacite-porphyrite.According to the detailed description of geological characteristics of gold deposit,combined with the metallogenic model of porphyry gold deposit and the characteristics of zircon U-Pb dating and geochemistry,it is proposed that Paodaoling gold deposit is a Cu-poor porphyry gold deposit formed in Early Cretaceous arc environment,and part of ore blocks experiences hydrothermal alteration.Ore bodies,which are controlled by NE-tectonic-magmatic belt with less than 1.0 km^2 outcrop area, are typical small intrusion forming large deposit.According to the principles of “similar analogy”,“spectrum of ore deposit”,“trend extrapolation”,“comprehensive information evaluation”,etc., there is a super-large gold deposit probably;meanwhile,Wushi,Baihushan and Zilaishan,which are controlled by the same NE-structure, are magmatic rocks developing areas, and the minerogenetic conditions are the same as that of Paodaoling gold deposit,so that these areas are important prospecting regions in further;especially,fracture belt alterated rocks and epithermal polymetallic sulfide deposits are important for the future study,because the rocks develop in Silurian with the same period of magmatic activities,and the deposits developed with porphyry deposits in the area.
出处
《地球科学与环境学报》
CAS
2014年第1期161-170,共10页
Journal of Earth Sciences and Environment
基金
安徽省国土资源科技项目(2011-K-08)
国家自然科学基金项目(41173057)
关键词
斑岩型金矿
英安玢岩
贫铜斑岩
矿床成因
找矿前景
长江中下游成矿带
porphyry gold deposit
dacite-porphyrite
copper-poor porphyry
deposit genesis
ore prospecting
the middle-lower Yangtze River metallogenic belt
