【作者】 吴堑虹；

【导师】 范蔚茗；

【作者基本信息】 中国科学院研究生院（广州地球化学研究所） ， 构造地质学， 2003， 博士

【摘要】 为更全面了解东大别山及北淮阳地区大地构造完整的演化，并为之提供研究实例积累，本研究主要从热年代学及造山后流体特点角度对东大别山及北淮阳构造区碰撞造山后中生代未-新生代初构造隆升活动进行了初步探讨。工作主要涉及磷灰石裂变径迹热年代学及造山后流体包裹体的热力学参数、物质组分及氢氧同位素等特征的研究，采用地质综合分析法探讨了热年代学、流体热力学参数及组分特征可能的构造意义；并用（U-Th）／He低温年代学方法进行了更低温（封闭温度为70℃）热构造年代学及构造意义的初步探讨，获得了对研究区中生代未-新生代初的构造隆升及演化的新认识，主要有以下新收获： 1) 研究区造山后构造隆升主要发生在晚侏罗世-早白垩世和晚白垩世-老第三系期间，隆升样式主要为穹隆隆升和断裂隆升，具有时间、空间格局上的不均一，且缓慢特点；研究区对青藏高原快速隆升没有明显的反应，暗示青藏高原快速隆升时中国东、西部的构造活动分别受不同动力学机制控制； 2) 中生代晚期到新生代早期研究区地壳处于以拉张应力作用控制为主的背景，地壳伸展拉伸，但涉深不大； 3) 晓天-磨子潭断裂在造山后演变为大陆内区域性断裂； 4) 通过实例比较研究，强调利用流体测温数据探讨流体捕获温度、压力和流体¹⁸O同位素时应该按照其基本理论要求注重压力校正； 5) 在裂变径迹测定方法改进、磷灰石T-t演化轨迹计算机模拟、近地质时期模拟T-t轨迹“吸热谷”产生原因的初步分析、自发裂变径迹对定年准确度影响的分析、磷灰石U-Th／He年龄的构造意义、系统利用流体信息探讨构造演化等方面的工作开展了有创新或改进性的工作，且效果良好。更多还原

【Abstract】 This preliminary research focus on the tectonic uplift in late Mesozoic-earlyCenozoic after the main collision oregeny to understand more and detail on the total process of tectonics evolvement in east Dabie Mountain and Beihuaiyuan area. The research works that have been done are: apatite fission track dating, apatite thermal-evolvement patterns; the fluid characteristics including fluid inclusions’ microthermometer, the compositions, 5 D - 8 18O, and their geochemistry , thermodynamics parameters. And also analyzed apatite’s U-Th/He ages to understand more about the last uplift. The research integrated the all information of apatite thermol-chronology, the thermodynamics parameters and compositions of fluid inclusions and discussed their tectonics implies. We get some improvements understanding in post collision orogeny in researched area which include:1) There were two main tectonic uplifts in the late of Mesozoic to early Cenozoic. One was in late Jurassic-early Cretaceous and another was in late Cretaceous-early Tertiary. The dome uplift and fault uplift with the heterogeneous evolution in time and space were main two uplift patterns. The uplift of post-orogency of this area was very slow and the amount of exhumation is about 3-4km since Cretaceous and it does not show sharp response for the uplifting of Tibet. It should imply the effect from the subduction and collision of Indian and Asian blocks was very limited in this area. During that the tectonic process in eastern and western of China were controlled by different dynamics mechanisms2) The researched area was controlled by stretch and extended during late Mesozoic-early Cenozoic;3) The Xiaotian-Mozitan fault acted just as a main fault in intro-continent. The uplift in Cenozoic was more effected by the stress adjusting in the crust.4) We tried and did some innovation work and got unproved results which include: dating fission track by a new method, modeling apatite T-t plot of below 120 , analyzing the impact of spontaneous track on dating and fluid inclusion’s tectonic implies. And the comparing research on fluid inclusions shows the pressure correction is very important to get fluid inclusions’ trapped temperature, pressure and 18O isotopic composition.更多还原