凤凰山矿田成矿地质条件和控矿因素分析

Analysis of the geological condictions of mineralization and the ore-control factors in Fenghuangshan field

讨论了地层、构造、岩浆岩与成矿的关系,指出矿田内与成矿有关的地层主要为三叠系下统南陵湖组(T1n)和龙山组(T1h).研究结果表明:主要控矿构造为处于接触带内的走向北北东、北北西和北西向的脆性扩容断裂,它们之间的相互追踪而构成的"之"字形断裂组合是矿体赋存的主要场所;成矿岩体主要为复式岩体中的花岗闪长岩和石英二长闪长斑岩,来源于统一的深部岩基,属来自幔源的中酸性钙碱性岩石,发育有各种类型的强烈的蚀变作用,具有形成矽卡岩型矿床和斑岩型矿床的巨大潜力;岩浆带来了大量的成矿流体、成矿物质和巨大的热能,是成矿最重要的因素,构造为岩浆的侵位和就位以及成矿流体的运移和沉淀提供了通道和场所;地层主要以其有利的岩性参与了成矿活动,三者的耦合作用,导致各种不同类型矿床(体)的形成;矿床(体)是岩浆 热液、地层、构造综合作用和有机组合的产物.

This paper discusses the relationship between mineralization and strata, structure, magmatite. The strata concerned with mineralization are Nanlinghu group(T1n) and Helangshan group(T1h) of lower Triassic. The main orecontrolling structures are brittle dilational faults in the contact zone, which strike along eastnorth by north, westnorth by north and westnorth directions. These faults track one another and form the zigzag fault assemblag which is the main place for hosting orebodies. The mineralization is mainly concerned with granodiorite and quartz monzodiorite porphyry of complex rockbody. Both of them come from the unite deepseated batholith, belonging to midacid calcalkaline rock from the upper mantle. All kinds of alterations concerned with rockbodies are very strong, showing enormous potential for skarn and porphyry mineralization. The magma is the most important factor for taking a lot of metallogenic fluid, metallogenic material and enormous thermal energy. The structure provides the passage and place for uplifting, locating of magma and migrating, precipitating of metallogenic fluid. The strata takes part in the mineralization by means of its favorable lithologic character. Their mutual combining effects result in the formation of all different kinds of ore deposits. The ore deposit is the common product of magma, strata and structure.