【作者】 葛良胜；

【导师】 邓军；

【作者基本信息】 中国地质大学（北京） ， 矿物学、岩石学、矿床学， 2007， 博士

【摘要】 滇西北是西南三江金多金属成矿带的重要组成部分，金属成矿作用与新生代富碱岩浆活动具密切的时空和成因联系。经特提斯复杂地质演化之后，本区处于一个由多陆块拼合形成的陆内环境之中。新生代特殊区域应力边界条件（地理位置）、青藏高原强烈碰撞造山过程、太平洋板块俯冲远程效应和深部多层架结构与分层受力条件下发生的壳-幔相互作用等多元构造动力体制复合，造就了本区复杂的成岩成矿地球动力学环境。陆内深部古（近）东西向构造带重新活动（表现为张性）与地壳浅部其他方向构造活动（主要为压扭性）联合控制着富碱岩体成岩及相关金多金属矿床成矿的时空一体化特征，表现为独立成区（滇西北）、东西成带、带内含多个集中区、成岩成矿形影相随。滇西北富碱岩浆岩是一套以富碱（K₂O+Na₂O＞8％）为突出特点的从基性到中酸性的岩石系列，主体形成于50-20Ma。而与之相关的金多金属矿床（区）表现出多型集中、成矿元素组合复杂、控矿因素多样、成矿时代基本一致的特点。根据富碱岩体δ¹⁸)：7.72～8.61‰；δ³⁴S：1.7～6.6‰；⁸⁷Sr／⁸⁶Sr：0.7054～0.7111；¹⁴³Nd／¹⁴⁴Nd：0.512319～0.512573，εNd（t）：-6.75～1.68；²⁰⁶Pb／²⁰⁴Pb：18.094～18.644，²⁰⁷Pb／²⁰⁴Pb：15.537～15.709，²⁰⁸Pb／²⁰⁴Pb：38.566～39.094；δ³⁰Si：0.0～0.4‰；稀土总量较高，不具或仅具微弱的δEu异常，呈右倾的近平滑配分曲线，La／Ce值变化为0.40-0.63；Ce／Nd为1.88-2.81；Sm／Nd为0.11-0.20等综合分析认为，其源区为具有富集地幔Ⅱ型地球化学特点的壳幔混合带。成矿流体属于富碱（K⁺、Na⁺），高Cl^-、CO₂，低Ca²⁺、Mg²⁺、S，并以H₂O为的地幔型流体。由近东西向构造活动激发并上升至岩浆源区，导致源区岩石部分熔融形成富碱岩浆。地幔富碱流体同时富含Au-Cu等矿质，在流体致浆过程中，通过水岩相互作用又汲取了岩浆源区内的矿质，并随岩浆一起演化和上升，在合适的空间或介质条件下分别成岩成矿。同富碱岩体相比，矿床地球化学特征在总体相似的同时，还依不同矿床类型、元素组合、产出位置等而各具特点。由此构成了滇西北区域多元构造动力体制及其构造体系-壳幔混合源区及富碱岩浆活动-地幔富矿质流体作用等复杂要素耦合的区域Fe-Cu-Mo-Pb-Zn-Au-Ag-As-Sb-Hg金多金属成矿系统，并可划分为受扬子板块和兰坪盆地两个不同地质构造背景控制的Cu-Pb-Zn-Au-Ag-As-Co-Hg-Sb和Fe-Cu-Mo-Pb-Zn-Au（-Ag）子系统。在各成矿集中区则表现为由不同类型矿化体、蚀变、物化遥异常构成的复杂而有序的矿化网络，并具有不完全相同的矿床地球化学特征。对成矿系统产物的变化和保存进行了详细研究，并根据成矿系统产物及其变化和保存特点，通过总结不同成矿产物的发现标志和找矿勘查方法组合的有效性，建立了与富碱岩体有关的金多金属矿床区域找矿模型。更多还原

【Abstract】 Northwestern of Yunnan province is important part of "southwestern-three river Metallogenic belt" of China. Au-polymetal deposits with characteristics of multiformity （poly-type） and concentricity （one-body） in this area had consanguineous relationships of space-time and genetic with the Himalayan alkali-rich magmatism. The geological and geochemical basic of tectonic-magma-fluid-metallization was formed by the complex tectonic evolvement of Tethys before Cenozoic. Mulriple tectonic dynamical systems of special regional stress field （geography position） , intense collision orogeny of Qinghai-Tibet plateau, long-range effect of the subduction of Pacific Ocean plate and strong crust-mantle interaction which occurred in the condition of multiply-layered structure with layered stress-concentration made up of the intricacy geodynamical environment of magmatism and metallization in Cenozoic. The unite-controlling of removement of intracontinental depth near EW trend paleo-structures（mainly spread） and other trend structures（compressed-twisted） in lower in crust to alkali-rich magmatism and related gold-polymetal mineralization formed the integrative features of the alkali-rich magmatite and the deposits, which in space distribution showed as independence region, EW trend rock and ore belt in the region and many Au multimetallic concentration area in the belt, and in era as simultaneity or near simultaneity. The magmatites emergenced in northwestern of Yunnan was a series of alkali-rich rocks （ K₂O+Na₂O>8% ） from basic to intermediate-acid and related deposit or mineralization concentration area had the common characteristics of poly types, poly elements, poly factors of ore-controlling and concurrent metallogeneic epoch. Studies of H,O,S,C stable isotopes, Pb,Sm-Nd,Rb-Sr,Si,He-Ar radioactive isotopes and REE geochemistry showed that the alkali-rich magma came of the mixed belt of crust and mantle with the geochemical feature of mantle-rich II type and formed by the fractional melting （and/or alkali-metasomatism） of the source rocks as a result of migrating up and infusing into the crust-mantle belt along deep faults（mainly EW-trending nearlly） of the hydrocarbon alkali fluid derived mantle. The fluid （it might be Au and Cu or other elements-bearing） moved up through melting body or accompanied the intrusions of the alkali-rich magma and obtained gold and other elements from the rocks the fluid passed by metasomatism, extraction and remobilization and then changed into ore-bearing hydrothermal solution. When it moved into some favorable space around the porphyry bodies （veins） in the shallow of crust, a series of gold （and other metal） deposits with different types and sizes formed. A regional gold mutlimetal metallogenicsystem related to the alkali-rich magmatism, which formed by complicated couplied of Mulriple tectonic dynamical systems, the mixed area of crust and mantle and alkali-rich magmatism and mantle ore-elements-rich fluid, was established in this paper in northwestern area of Yunnan province. This metallogenic system included two subsystems, one developed in the Yangtze plate and another in the adjacent Lanping-simao basin. The production of the metallogenic system comprised mineralization series （including sub-series） in regional scale and mineralization network of different types ore-bodies （such as porphyry type, skarn type, quartz vein type, structure altered rock type, （explosion） breccia type, laterite type and so on）, wallrock alteration, geophysical-geochemical-remote sensing abnormities,etc. in multimetallic concentration area scale. The changing and conserving of the metallogenic system production was detailedly discussed. According to the features and indications of the productions, together with the validity and adaptability of different exploration methods for deposit, a regional exploration model for deposit had been put forward.更多还原