【作者】 王清利；

【导师】 陈文；

【作者基本信息】 中国地质科学院 ， 地球化学， 2008， 博士

【摘要】 论文以天山及相邻地区（大致从北纬40度至北纬46度之间的我国疆土）为主要研究地区,以区内古生代以来发生的主要构造、岩浆及成矿事件的时代为主要研究内容,通过对岩浆活动及成矿活动的构造环境分析,探讨天山及邻区古生代的大地构造演化机制。国家多次组织“305”、“973”等重大项目开展研究,积累了大量的岩石学、构造地质学及矿床学等方面的资料。为发现构造、岩浆、成矿事件间的联系及事件的演化规律,进一步提高研究深度,对现有资料进行系统总结是非常必要的。为此,搜集整理了研究区古生代的构造事件、岩浆事件及成矿事件的年代学资料,并加以分析总结。此外,对东天山地区大规模的推覆事件、走滑事件及剪切带型金矿床作了重点解剖,开展了精细的⁴⁰Ar/³⁹Ar年代学研究,厘定了该区推覆、走滑的活动时代及剪切带型金矿的形成时代。取得的主要进展有:（1）总结归纳并初步探讨了氩—氩年龄谱的基本类型及其地质意义,根据受扰动的氩—氩年龄谱识别出东天山地区金成矿后期的剪切构造事件。（2）总结了区内构造事件的年代学成果,并对东天山地区的推覆及走滑事件进行了⁴⁰Ar/³⁹Ar年代学研究,对天山及邻区古生代构造演化取得了更深入、更全面的认识。（3）通过对岩浆岩年代学成果的总结分析,发现研究区古生代与板块俯冲及碰撞相关的酸性岩浆活动的时空规律是:自东向西由老到新,自北向南由老到新。反映了塔里木板块与西伯利亚板块的拼合过程是先北后南,先东后西逐步完成的。（4）总结发现新疆西部锡矿带自北向南形成时代由老到新,反映了哈萨克斯坦板块先与北部的准噶尔板块拼合碰撞,后与南部的伊犁板块拼合碰撞。（5）通过精细的⁴⁰Ar/³⁹Ar年代学研究,厘定了东天山地区剪切带型金矿床的形成时代,并且发现自西向东金矿床形成时代由老到新,反映了该地区自西向东差异性隆升过程。（6）探索出依据碱性岩的碱质组合类型判别其产出构造环境的新方法;并对准噶尔盆地东北缘及塔里木北缘的碱性岩产出的构造环境进行了判别,发现准噶尔盆地东北缘的碱性岩形成于走滑剪张的构造环境,塔里木盆地北缘的碱性岩形成于拉张伸展环境。（7）对区内晚石炭世—早二叠世发生的大规模弥散性伸展作用的机制提出了新解释,认为是大规模的软流圈地幔上侵结果。更多还原

【Abstract】 We study the times of the tectonic,the magma and mineralization events since the Paleozoic in Tianshan and adjacent areas（the range roughly from N 40°to N 46°,China）.The Paleozoic tectonic evolution mechanism of this area was discussed by the analysis of the tectonic settings of magma activity and mineralization activity.In the recent ten years,several "305" and "973" projects have been finished and some are under performing,many progresses about petrology,geotectonic,ore deposit have been made.It is very necessary to summarize the exist results systematically for finding out the relationship among the structure, the magma,the mineralization events and the evolution of these events.Therefore the exist results of the structure,the magma and the mineralization events were collected,analyzed and summarized here. Furthermore,we analyse the thrust-slip and strike-slip events taking place in Eastern Tianshan according to their ages measured by the precise ⁴⁰Ar/³⁹Ar dating,and determined their active times and the forming ages of the shear-type gold deposits.The progress from this paper as follows:（1） The geological meaning of several types of ⁴⁰Ar/³⁹Ar age spectra was discussed.In addition,the ⁴⁰Ar/³⁹Ar age spectrum of the sericite from the gold deposit in Eastern Tianshan shear zone show a little disturbed,indicating that the shear tectonic events took place after the gold deposit.（2） We summarized the ages of the tectonic events in this area and study the nappe and the strike-slip event of East-TianShan using ⁴⁰Ar/³⁹Ar method.Therefore,we further understand the Paleozoic tectonic evolution in Tianshan and adjacent areas.（3） The Geochronology results from the magmatic rocks in study area show that the features of the acid magmatism in Paleozoic are that the ages of the rocks became younger from the eastern to the western and from the northern to the southern.This suggests that the matching of the Tarim plate and the Siberia plate began from the east to the west and from the north to the south gradually.（4） The ages from the tin deposits show that the times of the tin deposits located in the western Xinjiang became younger from the north to the south,reflecting the matching of the Kazakhstan plate and the Junggar firstly,and then with Yili plate.（5） The forming ages of the shear zone gold deposits in East Tianshan are determined by the precise ⁴⁰Ar/³⁹Ar analysis.The results show that the age of the gold deposit become younger from the west to the east gradually,indicating the differential uplifting of the East Tianshan area from the west to the east.（6） A new way to discriminate the tectonic setting of alkaline rocks was established,and the tectonic setting of the rocks from the northern margin of Tarim basin and north-eastern margin of Junggar basin were discriminated by this way.The results show that the alkaline rocks in the northern margin of the Tarim basin formed under the extending environment and the alkaline rocks in the north-eastern margin of the Junggar basin formed under the extension environment caused by the strike-slip.（7） A new point about the mechanism of the large-scale extension in Late Carboniferous - Early Permian in study area is presented that this large-scale extension is caused by the intrusion of asthenosphere mantle.更多还原