云南梁河来利山锡矿控矿地质因素与成矿作用分析

【作者】 丁秀芳；

【导师】 高建国；

【作者基本信息】 昆明理工大学 ， 构造地质， 2009， 硕士

【摘要】 梁河来利山锡矿床是滇西锡矿带西亚带的主要的矿床类型之一。该矿床位于印度板块与欧亚板块碰撞带前缘的腾冲—梁河弧形构造的转折部位,东邻三江构造带。矿床与喜山期的花岗岩岩浆活动有着密切的时空关系和成因联系,经过热液作用形成了由老熊窝、淘金处、三个洞矿段组成的矿化富集区。经过野外地质调研和收集前人的资料,综合分析研究了组成矿床的矿体形态、规模和产状,矿石的类型、结构构造、矿石成分、围岩蚀变,通过对矿床的控矿地质因素与成矿作用分析,取得以下成果：1、通过对来利山锡矿成矿地质条件的研究,成矿物质主要来源于喜山期的花岗岩,在成矿作用过程中,围岩中也有部分锡进入成矿流体,从而为成矿提供了物质基础。矿床属于黄铁矿—云英岩型热液矿床。2、区内矿体主要赋存在中石炭统丝光坪组上段第三层(C2s2-3)和第五层(C2s2-5)的构造破碎带中。矿体与围岩呈渐变过渡关系。矿体主要产于85-62勘探线之间,走向40-80°,受弧形断裂破碎带控制,倾向北西、倾角60-90°,作北东向展布,呈一向南东凸出的弧形,平面上呈“S”型。主断裂的规模越大,矿体规模越大,反之亦然。矿体在空间上成雁行状排列,在平面上呈脉状、分枝复合脉状、透镜状,在剖面上呈楔形尖灭。部分矿体由于受后期构造的改造,出现变薄和增厚的现象。3、该区喜山期花岗岩的侵位为成矿提供了主要的物质来源,在成矿作用过程中围岩也提供了部分成矿物质,从而构成形成锡矿体的物质基础。强烈的构造运动为含矿热液提供了交代、运移、沉淀的条件；持续的构造运动和连续的岩浆分异,使之多期次的成矿物质叠加,形成锡矿床。成矿期后构造作用,虽使矿体遭到破碎,但基本保留了原来的面貌。4、成矿严格受构造控制,它不仅是成矿流体的运移的通道,也是成矿物质沉淀的场所。断裂给含矿热液提供了交代、运移、沉淀的有利通道和场所。5、直接找矿标志为：铁帽,云英岩化、黄铁矿化、硅化和褪色蚀变；间接标志为受花岗岩外接触带中北东向构造破碎带控制的石炭系中统丝光坪组上段(C2s2)地层。6、大致圈定了三个有利的成矿地段：三个硐南部—老熊窝矿段的北部一带、潘家坟—淘金处之间和白沙坡—蛇洞一带。更多还原

【Abstract】 The Lianghe Lailishan tin ore deposit is a main deposit type in the western subzone of the Western Yunnan tin ore zone. This ore deposit is located at the transition spot of Tengchong-lianghe arc structure,that ramed east neighbour three rivers structure belt,which is in the preceding plart of the Indian and Eurasia tectonic plates collision belt. There are close time and space relations and origin relation between the ore deposit and the granitic magma activity of the Ximalaya mountain time, formed after the hydrothermal process by the Laoxiongwo, has panned for Taojinchu the mineralization which place, Sangedong ore section was composed to concentrate the area.After geological research on the field and the collection of previous information, and analyzing comprehensively and researching ore-body shape, size and occurrence which composed the deposit, the ore types, structure, mineral composition, wall rock alteration, we achieved the following results through analyzing the ore-controlling geological factors of deposits and metallogenesis:1. We know that ore-forming materials come mainly from the Himalayan granite by studying the ore-forming geological conditions of Tin on the Laili Mountain, and there were parts of Tin in the wall rock going in the ore-forming fluids at the process of mineralization, so as to provide a material basis for ore-forming. The deposits belonged to Pyrite-Cloud British rock type hydrothermal deposits.2. The ore-body in the zone exists mainly in the tectonic belt broken of the Upper Carboniferous Ping mercerizing upper third layer (C2s2-3) and fifth layer (C2s2-5). Ore body and surrounding rock was gradually transiting.The ore-body is mainly in the 85～62 exploration line, in the way 40～80°, inclined to the North West, angle 60～90°, for distribution to the North East, showed a protrusion arc though south and east, and "S" type on the plane as controlled by the arc fault fracture zone. The larger was the scale of main faults, the larger the ore-body was, and vice versa. The ore body was up into a flying-geese-like arrangement in space, on vein in the plane, composite vein branches, lenticular, and pinch-out wedge-shaped at section on. Parts of ore-body emerged the phenomenon of thinning and thickening due to the transformation of the late tectonic.3. Emplacement of Himalayan granite provided the main material source for the ore-forming, and wall rock also provided some ore-forming materials at the process of mineralization, thus constituted the material basis of forming the body of tin. Strong tectonic movement provided the condition of account, migration, sedimentation for ore-bearing hydrothermal; Sustained tectonic movements and continuous magma differentiation made so many stages of minerals into the superposition, and took shape tin deposits.4. Strictly controlled mineralization, the tectonic is not only the migration channel of Ore-forming fluid, but also the place of minerals precipitate. Fracture provided the favorable channel and places of account, migration, sedimentation for ore-bearing hydrothermal.5. Logo for direct prospecting are rail cap, cloud of the British rock, pyritization, silicification and bleaching alteration; and indirect signs are Carboniferous in the EC group on mercerizing Ping paragraph (C2s2) formation which is controlled by the tectonic fracture zone in the way of North East.in the granite outside the contact zone.6. We delineated roughly three favorable metallogenic lot:southern part of Three holes-northern section of Laoxiong brood paragraph mine, between Panjia grave and Gold Rush Service, and Baisha slpoe-Snake hole area.更多还原