广西龙头山斑岩金矿成矿岩体的岩石学、岩石地球化学及热液蚀变作用特征  

Petrologic,Petro-Chemical and Hydrothermal Alteration Characteristics of Porphyry Pipe in Longtoushan Gold Deposit

作　　者：曾南石[1,2] 张春鹏[3] 徐文炘[4] 朱文风[2] 邱桂龙 

机构地区：[1]桂林理工大学广西地质工程中心重点实验室 [2]桂林理工大学有色及贵金属隐伏矿床勘查教育部工程研究中心,广西桂林541004 [3]沈阳地质调查中心,沈阳110032 [4]桂林矿产地质研究院,广西桂林541004 [5]广西龙头山金矿,广西贵港537100

出　　处：《桂林理工大学学报》2011年第1期1-10,共10页Journal of Guilin University of Technology

基　　金：广西自然科学基金项目(桂科自0640179);广西地质工程中心重点实验室主任基金项目(桂科能07109011-Z009);广西有色金属集团项目(GYDK090012)

摘　　要：根据镜下特征及SiO2含量,将龙头山金矿成矿岩体的构成主体重新定名为花岗闪长斑岩。岩浆期后气液导致岩体上部发生弥散型绢云母化和高岭石化;受热流体的酸碱分离作用影响,形成高岭石化相对在上、绢云母化在下的垂直蚀变分带。侵入岩浆带来的热能,同时形成有大气降水加入的富硼含矿热液,并沿岩体接触带及顶部发育的碎裂构造等开放空间充填,交代已绢云母化、高岭石化的花岗闪长斑岩,形成围绕岩体的近环状含金隐爆角砾岩和电气石-硅化带。微量元素与同位素测年研究表明,成矿岩体的成岩物质来源于燕山晚期受混染的I型花岗岩浆;与周边岩体在成岩物质、侵位空间及成岩时代等方面表现出岩浆活动的一致性。The Longtoushan porphyry related to gold mineralization is reconfirmed with granodiorite porphyry based on SiO2 contents and residual hornblende.Hydrothermal fluids from magmatic system formed sericite zone at lower part,and kaolinite zone at upper portion in the granodiorite porphyry.B-rich Au-bearing hydrothermal fluid which mixed meteoric water from the heat of magma intrusion filled in the fractures surrounded the porphyry pipe,replaced the altered porphyry rock,and formed the zone of gold mineralization and tourmaline alteration.Petro-chemical characteristics and isotope dating suggest that the Longtoushan porphyry pipe was formed by I type magma which has been contaminated by some materials from crust.The porphyry intrusion has the similar materials of rock-forming,structure setting,and timing with other intrusions found in the surrounding areas.

关 键 词：斑岩金矿 隐爆角砾岩 花岗闪长斑岩 热液蚀变分带 龙头山 广西 

分 类 号：P618.51[天文地球—矿床学]