新疆东天山地区土屋和延东铜矿床斑岩-叠加改造成矿作用  

Porphyritic-overlapped mineralization of Tuwu and Yandong copper deposits in Eastern Tianshan Mountains, Xinjiang

作　　者：王云峰[1,2] 陈华勇[1] 肖兵[1,2] 韩金生[1] 杨俊 

机构地区：[1]中国科学院广州地球化学研究所矿物学与成矿学重点实验室,广东广州510640 [2]中国科学院大学,北京100049 [3]新疆地质矿产开发局第一地质大队,新疆昌吉831100

出　　处：《矿床地质》2016年第1期51-68,共18页Mineral Deposits

基　　金：国家重点基础研究计划“973”项目“新疆北部古弧盆体系成矿机理(批准号:2014CB440802)”资助

摘　　要：土屋和延东铜矿床位于东天山大南湖-头苏泉岛弧带南部,是中亚成矿带的重要组成部分。文章根据脉次穿插关系、蚀变矿物组合及矿物共生关系,将土屋和延东铜矿床均划分为斑岩成矿期、叠加改造期和表生期3个期次。土屋铜矿床的铜矿化形成于斑岩成矿期和叠加改造期,而延东铜矿床的铜矿化主要形成于叠加改造期;土屋和延东铜矿床伴生的钼矿化主要形成于叠加改造期。因此,笔者认为前人获得的辉钼矿Re-Os年龄（326.2-322.7 Ma）代表叠加改造期的成矿年龄,该期矿化与石英钠长斑岩（（323.6±2.5）Ma）的侵入相关,而斑岩成矿期的矿化与斜长花岗斑岩（339-332 Ma）相关,成矿年龄为341.2-333.9 Ma。叠加改造期的存在,使得斑岩成矿期的蚀变分带可能受到了叠加和破坏。The Tuwu and Yandong copper deposits, located in the southern segment of the Dananhu-Tousuquan island arc belt, are important parts of the Central Asian Metallogenic Belt. According to the crosscutting relationships and mineral assemblages, the mineralization in both Tuwu and Yandong copper deposits can be divided into three periods： the porphyritic-mineralization period, the overlapped-mineralization period and the supergene period. The porphyritic-mineralization period and the overlapped-mineralization period are the metallogenic periods of copper in the Tuwu copper deposit, while the overlapped-mineralization period is the most important copper metallogenic period in the Yandong copper deposit. In addition, the associated molybdenite mineralization was mainly existent in the overlapped-mineralization period in Tuwu and Yandong. Therefore, the molybdenite Re-Os ages（ 326. 2 - 322. 7Ma） obtained in previous studies should represent the age of the overlapped-mineralization period in the Tuwu and Yandong copper deposits, and the porphyritic-mineralization, with the age of 341. 2 - 333. 9 Ma, is the result of the ore-bearing plagiogranite porphyry（ 339 - 332 Ma）. The emplacement of quartz albite porphyry（（ 323. 6 ±2. 5） Ma） is thought to have caused the overlapped-mineralization which destroyed and modified the previous porphyritic-mineralization.

关 键 词：地质学 土屋-延东 铜矿床 成矿期次 斑岩-叠加改造成矿 

分 类 号：P618.41[天文地球—矿床学]