【作者】 刘忠法；

【导师】 邵拥军；

【作者基本信息】 中南大学 ， 矿产普查与勘探， 2009， 硕士

【摘要】 龙门山铜多金属矿床位于扬子地块北缘下扬子台坳沿江断褶带中段的月山岩体内以及岩体与围岩的接触带中,是长江中下游铜铁成矿带重要矿床之一。在对区域地质背景、矿床地质特征、矿床地球化学特征、成矿地质条件分析的基础上,开展了月山地区控矿因素、成岩机制、矿床成因、成矿模式等方面的研究。论文的研究成果与创新主要有以下几点：l、通过对区域地质背景的分析,研究了矿床地质特征、矿体特征、矿石特征,在此基础上,根据矿物共生组合关系,将龙门山铜多金属矿床的成矿作用分为两期六阶段,即：矽卡岩期：早期矽卡岩阶段(透辉石矽卡岩等)、晚期矽卡岩阶段(石榴子石矽卡岩、磁铁矿)、氧化物阶段(钾长石、角闪石、黑云母等)；硫化物期：石英阶段、硫化物阶段(黄铜矿、黄铁矿及少量的斑铜矿)和碳酸盐阶段(碳酸盐矿物及少量的镜铁矿)。2、根据矿区岩浆岩岩石化学特征、稀土元素和微量元素地球化学特征,得出本区闪长岩类造岩元素K2O/(K2O+Na2O)和Al2O3/(CaO+Na2O+K2O)的指标值分别为0.39～0.41和1.30～1.37,LREE/HREE为8.37～12.84,Sr的丰度较高,平均为881.31×10-6,最高达4840×10-6,远高于上地壳值350×10-6和下地壳值230×10一,显示本区形成月山岩体的原始岩浆来源于上地幔,岩体具富钠、钾的特征,同时富钙的特征也比较明显,其原因可能是岩浆上升时遭受了地壳钙质混染,即地壳的同化混染作用。3、探讨了地层、构造、岩浆岩以及围岩与成矿的关系,认为地层提供了部分成矿物质；构造是本区成矿的必要因素,控制了岩浆的侵位及其成矿岩体和矿体的形成和就位；燕山期岩浆岩是有利的成矿母岩,是本区成矿物质的主要提供者；围岩及围岩裂隙是本区成矿的重要条件,控制脉状矿体的产状与规模。4、通过对矿床地质特征、地球化学特征、控矿因素以及成岩机制的分析,认为龙门山铜多金属矿床的形成与燕山期中酸性岩浆侵入活动有密切的关系；在综合研究本区成矿环境、岩浆来源、岩浆演化机制的基础上,建立了同源多期多位一体的成岩、成矿模式,认为龙门山铜多金属矿床是以中酸性岩浆热液交代为主的脉状矽卡岩型铜多金属矿床。更多还原

【Abstract】 Longmenshan copper-polymetallic deposit is located in Yueshan rock mass which is located in the middle of broken fold belt in northern margin of Yangtze block as well as between rock mass and hosting rock contact strip, and this deposit is one of the most important deposits in middle and lower Yangtze River of copper metallogenic belt. Based on the analysis of the characteristics of geological background, geological characteristic of deposit ore, geochemical of deposit and metallogenic geologic condition, author researches on the ore-controlling factors, rock-forming and mechanism, the genesis of deposit, metallogenic pattern and etc.The main achievements are made as follows:1.Through the analysis of the regional geological background, author researches the characteristics of deposit, orebody and ore, and then divides the mineralization of Longmenshan copper deposit into two stages and six phases by the relation of mineral paragenetic association, namely:skarn stage:early skarn phase (diopside skarn and etc), terminal skarn phase(garnet skarn, magnetite), oxide phase(potash feldspar, hornblende, biotite and etc);sulfide stage:quartz phase, sulfidic stage (chalcopyrite, pyrite and bornite)and carbonate phase (carbonate minerals and specularite).2.According to petrochemical characteristics of magmatic rocks, trace elements and REE geochemiscal characteristics of Yuesahn mining area, we draw the conclusion that the rock-forming elements of diorite K2O/(K2O+Na2O) and Al2O3/K2O+Na2O+CaO’s index value are 0.39～0.41 and 1.30～0.69 respectively, LREE/HREE is 8.37～12.84,Sr has higher abundance, average 881.31×10-6,top to 4840×10-6 much higher than the upper crust values of 350×10-6 and the lower crust values of 230×10-6,and it display the initial magma root in upper mantle which form the rock body of Yueshan, and rock body has the character of rich kalium and natrium, as well as the character of rich calcium is obvious, consistent with that rock is rich in calcic mineral.The reason may be that when the magma rises, it suffers from the crust calcic matter’s strong contamination, which is called the crust’s assimilative hybridism.3.This dissertation discusses the relation between stratum, structure, magmatic rock, hosting rock and mineralization, recognizing that the stratum offer part of the mineralized matter, the structure is the necessary factor of intrinsic region mineralization, which controls the intrusion of magma, the formation and location of minerogenetic rock and ore-body. The magmatic rock of Yanshan stage is favorable matrices. Wall rock and wall rock cranny is fundamental conditions of intrinsic region mineralization, which controls the attitude and scale of vein orebody.4.By analyzing the characteristics of the ore deposit geologic and geochemical, rock-forming mechanism and ore-controlling factors, author considers that the formation of the Longmenshan copper deposit has intimate relation with the intruder operations of the Yanshan stage middle acidite magma. On the bases of the aggregate researching of metallogenic environment, magma origin and magma evolving mechanism, the rock-forming and metallogenic pattern that is homologous multi-period has been established.Author consider the Longmenshan deposits are vein skarn-type copper-polymetallic deposits,which Metasomatism is intermediate-acid magmatic hydrothermal mainly.更多还原