高校地质学报2018，Vol.24Issue(3)：353-370,18.DOI:10.16108/j.issn1006-7493.2017126
新疆西南天山阿万达金矿区赋矿围岩物源及形成时代:碎屑锆石U-Pb年代学制约
Sedimentary Provenance and Age of the Ore-hosting Strata in the Awanda Gold Deposit in the Southwest Tianshan Area, Xinjiang:Constraints from Detrital Zircon U-Pb Dating
摘要
Abstract
The Awanda gold deposit is located in the Southwestern Tianshan Orogenic Belt. On the basis of the geological characteristics of the Awanda gold deposit, the authors applied petrological geochemistry and LA-ICP-MS detrital zircon U-Pb dating of the siliceous schist wall rocks from the So-called Aksu Group, which is closely related to the mineralization of Awanda gold deposit, with an aim to understand depositional environment, provenance and age of these rocks. The results of petrochemistrical analysis show that the protoliths of the ore-hosting strata are possibly composed of mudstones and sandstones with low maturity. Most of the provenances are quartzose sediments and the depsotional environment is likely related to depositional basin nearby the active continent margin. LA-ICP-MS detrital zircon U-Pb date indicates that the zircon ages have peaks of weighted age of 405 or 406 Ma. The youngest peak age of these concordant age data is 405 Ma which could be regarded as the maximum sedimentary age. Therefore, it was considered that the sedimentary age of the so-called Aksu group ore-hosting strata is not older than the Early Devonian, rather than the Changcheng period as previously reported. In addition, the provenances of the strata are multiform. Among the analytic data, the~405 Ma detrital zircons occupy the principal part, which could be related to the magmatic activity in the northern rim of the Early Devonian volcanic arc of the Haerke Mountain. The ~745 Ma detrital zircons suggest that small part of the material source comes from Neoproterozoic rocks. Several~2.50 Ga detrital zircons reflect that North China block makes few contributions of material sources to the strata.关键词
西南天山造山带/阿万达金矿/原岩恢复/沉积环境/沉积时限/物源Key words
Southwestern Tianshan Orogenic Belt/Awanda gold deposit/reconstruction of protolith/sedimentary environment/sedimentary age/sedimentary provenance分类
天文与地球科学引用本文复制引用
付宇,丁清峰,吴昌志..新疆西南天山阿万达金矿区赋矿围岩物源及形成时代:碎屑锆石U-Pb年代学制约[J].高校地质学报,2018,24(3):353-370,18.基金项目
国家重点研发计划(2017YFC0601203) （2017YFC0601203）
中国地质调查局工作项目(1212011140056) （1212011140056）
自然科学基金项目(40802011)联合资助 （40802011）
