【作者】 郭利果；

【导师】 刘玉平；

【作者基本信息】 中国科学院研究生院（地球化学研究所） ， 地球化学， 2006， 硕士

【摘要】 本文通过对滇东南老君山变质核杂岩各组成单元的地质特征、地球化学、热年代学等详细而系统的研究，得到了如下结论： (1)老君山地区存在古元古代结晶基底和中、新元古代岩浆活动，其中新元古代岩浆活动与华南(超级)地幔柱侵入、罗德里亚大陆裂解有关。 (2)南捞片麻岩与南温河花岗岩同属加里东期扬子板块与华夏板块同碰撞造山环境产物，两者同属变质泥岩、砂岩及中基性岩上壳岩部分熔融的S型花岗岩。 (3)老君山变质核杂岩基本形成时限在印支期250-160Ma，之后经历了不断隆升并在第三纪末出露剥蚀的过程。 (4)在老君山变质核杂岩韧-脆性基底拆离断层系和韧性核部剥离断层系各存在一次大规模的成矿作用，前者形成了南秧田、新寨等大型矿床，后者形成了都龙超大型矿床。时代分别为晚印支期的220-200Ma左右和晚燕山期80Ma左右。 (5)越北古陆的构造属性属于扬子和华夏板块拼贴前的华夏板块，即属于华南板块构造单元而非印支板块构造单元；Song Ma和Day Nui Con Voi剪切带之间的部分是从扬子板块西缘走滑剪切600km的杂岩体，亦非印支板块构造单元。 (6)较为详细论证了老君山地区的构造演化过程，并对滇东南泥盆纪-三叠纪末的构造演化提出了新的模式，即Song Ma古缝合线是印支板块与华南板块陆陆碰撞的残留形迹，八布蛇绿岩是大陆边缘前陆盆地局部海盆化的产物，其构造位置在俯冲期位于弧后盆地位置，在陆陆碰撞其位于前陆褶皱冲断带位置。 此外，本文还对利用都龙锡锌多金属矿床矿石中的锡石TIMS U-Pb定年方法进行了探索，确定了行之有效的锡石溶解的实验流程及方法，并首次获得都龙锡锌多金属矿床矿石中锡石TIMS U-Pb年龄为79.1±1.6Ma，证实了锡矿化主要与燕山晚期岩浆热液活动有关。更多还原

【Abstract】 According to the systematic researches on the geology, geochemistry and thermochronology of the Laojunshan metamorphic core complex, these preliminary conclusions had been drawn as follows.Firstly, in the Laojunshan area, it was indicated that there should exist the Paleoproterozoic basements rocks and Mesoproterozoic and Neoproterozoic magmatism, which related to the Neoproterozoic super mantle plume beneath South China Block and the breakup of the Rodinia Super-continent.Secondly, the Nanlao Gneiss and the Nanwenhe Granites were productions of same Caledonian magmatism related to collision between Yangtze and Cathaysia blocks, and both were S-type granites derived from partial-melting of the metamorphosed muldstone, sandstone and moderate-basic rock.Thirdly, the Laojunshan metamorphic core complex formed at ca. 250Ma to ca. 160Ma, followed by posterior brittle upheaving, and finally exhumated at the end of Tertiary.Forthly, two large scale mineralization events had been identified along the ductile-brittle and the ductile detachment systems, separately. The first one happened at ca. 220 Ma to ca. 200Ma and formed the Xinzhai and Nanyangtian tin-tungsten deposits, and the second took place at ca. 80 Ma and formed the Dulong tin-zinc deposit.Fifthly, North Vietnam Oldland was a part of the Cathaysia block before the collage between the Cathaysia and the Yangtze blocks. The terrane between Song Ma shear zone and Day Nui Con Voi shear zone was sheared about 600km along the left-lateral Ailaoshan-Red River Shear system, and was also a part of the South China Plate rather than a part of the Indochina Block.Sixthly, based on the geology, geochemistry and thermogeochronolgy, the tectonic implications of the Laojunshan metamorphic core complex had been discussed. The Song Ma Suture should present the collision between the Indochina更多还原