滇西北北衙斑岩型金多金属矿床成矿构造解析及找矿方向

发布时间：2018-07-01 18:03

本文选题：成矿构造解析 + 成矿构造体系　；参考：《昆明理工大学》2015年硕士论文

【摘要】：滇西北北衙金多金属矿床是西南三江多金属成矿带新生代斑岩成矿系统的典型矿床,是近些年来取得重大找矿突破形成的超大型金多金属矿床。运用矿田地质力学的理论和方法,通过大比例尺构造剖面精测,进行典型成矿构造几何学、运动学及构造岩特征解析,重点进行构造形迹力学性质的鉴定和矿田构造体系的划分,在此基础上分析控矿构造型式,确立成矿构造体系,总结构造控矿规律,进而探讨构造控岩控矿作用机制并建立构造控矿模式,指出找矿方向。论文主要取得了以下成果和认识：1、北衙金矿区构造发育,并且具有多期构造活动特征,以近SN向北衙向斜为主的褶皱和近SN向、近EW向为主的断裂为矿区内高级别构造,控制了斑岩和矿床(体)的分布,而节理作为低级别构造控制了矿脉的展布,反映了构造的挨次控制关系,构成了一套褶皱-断裂-节理成岩成矿构造系统；2、构造对富碱斑岩的侵位和成矿的发生起到主导性控制作用,根据控制不同矿床(体)的构造及其成矿作用特征,将矿床体划分为五类：1)受控于斑岩体内断裂、节理裂隙的斑岩型Au、Cu矿体；2)受控于斑岩与围岩接触带构造的矽卡岩型Au、Fe、Cu矿体；3)受控于围岩层间断裂破碎带、断裂、节理裂隙的热液脉型Au、Fe矿体；4)受岩溶洞穴及不整合接触界面控制的氧化淋滤富集型Au矿体；5)受控于爆破角砾岩筒构造的隐爆角砾岩型Au、Fe矿体；3、通过构造形迹力学性质鉴定,认为矿区自燕山晚期-喜马拉雅早期以来主压应力主要经历了近EW向→近SN向→NW向→近EW向的转变过程,形成了南北构造带、东西构造带和北东构造带,并分别归属于三江-滇中经向构造体系金沙江-程海南北构造带、云南纬向构造体系汤丹-鹤庆-兰坪东西构造带和丽江北东构造带；4、北衙金矿区控矿构造型式主要为“接触带”控矿构造型式和“多字型”构造型式,是在喜马拉雅中期东西构造带形成时期形成和发展起来的。东西构造带是控制喜马拉雅中期大规模斑岩型-矽卡岩型-热液脉型-隐爆角砾岩型矿床(化)的主导性构造体系,早南北构造带构成北衙金矿区成岩成矿构造格架,晚南北构造带则是控制喜马拉雅晚期氧化淋滤富集型矿床(化)的主导性构造体系；5、通过构造控矿规律分析及构造控矿模式的建立,认为围岩与岩体接触带构造、层间断裂破碎带、近南北向张性断裂及节理构造是北衙金矿区未来有利找矿部位,指出北衙金多金属矿床北段炭窑地区具有重大找矿潜力。
[Abstract]:The Beiya gold polymetallic deposit in northwestern Yunnan is a typical deposit of Cenozoic porphyry metallogenic system in the Sanjiang polymetallic metallogenic belt in southwest China. It is a super large gold polymetallic deposit formed by major ore prospecting breakthroughs in recent years. By using the theory and method of ore field geomechanics, the typical ore-forming structure geometry, kinematics and tectonite characteristics are analyzed by fine surveying of large scale structural profile. Emphasis is placed on the identification of the mechanical properties of structural traces and the division of structural systems in the ore field. On this basis, the ore-controlling structure pattern is analyzed, the ore-forming structure system is established, and the rules of structural ore-controlling are summarized. The ore-controlling mechanism of tectonic rock is discussed and the tectonic ore-controlling model is established, and the prospecting direction is pointed out. The paper has obtained the following achievements and the understanding that the Wei-1, Beiya gold ore area has developed structure, and has the characteristics of multi-stage tectonic activity. The fold and near SN direction of near SN direction Beiya syncline and the near EW trending fault are high grade structures in the mining area. The distribution of porphyry and deposit (body) is controlled, while the distribution of ore vein is controlled by joint as a low grade structure, which reflects the order control relation of structure, and constitutes a set of fold, fault-joint diagenetic and metallogenic structure system. 2. Structure plays a leading role in controlling emplacement and metallogenesis of alkali-rich porphyry. According to controlling the structure and metallogenic characteristics of different deposits (bodies), the deposit body is divided into five types: 1) controlled by porphyry faults. The porphyry type Au-Cu orebody of joint fissure is controlled by skarn type Au-Fe Cu orebody which is controlled by porphyry and surrounding rock contact zone structure, and is controlled by interlayer fracture zone of surrounding rock, fracture and joint fracture of hydrothermal vein type Au-Fe orebody. 4) the oxidized leaching enriched au orebody controlled by karst cave and unconformity contact interface is controlled by the crypto-explosive breccia type Au-Fe orebody of blasting breccia tube structure, and the mechanical properties of structural trace are identified. It is considered that since the late Yanshanian and early Himalayan periods, the main compressive stress has mainly undergone the process of transition from near EW to NW and NW to EW, resulting in the formation of the north and south tectonic belts, the east-west tectonic belts and the northern and eastern tectonic belts. They belong to the Jinshajiang-Chenghai tectonic belt of Sanjiang-Central Yunnan meridional system, the Tangdan-Heqing-Lanping East-West tectonic belt of the zonal structural system of Yunnan Province and the northern and eastern structural belt of Lijiang. 4. The ore-controlling structural pattern of Beiya gold deposit is mainly "contact zone" and "multi-zigzag", which was formed and developed in the East-West tectonic belt in the middle Himalayas. The east-west tectonic belt is the dominant structural system controlling the large scale porphyry type skarn type hydrothermal vein type crypto-explosive breccia type deposit in the middle Himalayan period. The early north-south structural belt forms the framework of diagenetic and metallogenic structure in Beiya gold deposit area. The late north-south structural belt is the dominant structural system controlling the late Himalayan oxidized leaching and enrichment type deposits. Through the analysis of the tectonic ore-controlling law and the establishment of the tectonic ore-controlling model, it is considered that the structure of the contact zone between surrounding rock and rock mass. The interlayer fracture zone, the nearly north-south extensional fault and the joint structure are the favorable ore-prospecting sites in the Beiya gold deposit in the future. It is pointed out that the northern section of the Beiya gold polymetallic deposit has great prospecting potential.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.2

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