中国—吉尔吉斯斯坦天山构造格架与演化
Tectonic framework and evolution of Tianshan in China and Kyrgyzstan
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摘要: 中国—吉尔吉斯斯坦天山地处中亚天山造山带中段,地质构造复杂,矿产资源丰富。在前人资料基础上,基于区域构造-岩石组合的分布发育及时空属性特征,统一将研究区划分为哈萨克斯坦和塔里木两大板块,二者由南天山晚古生代缝合带所焊接。其中,进一步划分为5个二级单元,18个三级单元。研究认为,研究区内北、中、南天山构造格架连续,在800 Ma(相当于南华纪下限)前后都完成了大陆块体的拼合,成为全球新元古代罗迪尼亚超大陆的组成部分。此后经历了大致相同的构造演化史,从中二叠世开始全区转化成陆内盆山构造格局,新生代印度大陆同欧亚大陆碰撞使这一陆内盆山构造格局不断臻于完善。Abstract: Tianshan in China and Kyrgyzstan is located in the middle of Tianshan orogenic belt, with complex geological structure and abundant mineral resources. On the basis of previous studies, and according to the distribution and space-time characteristics of regional tectonic-rock combination, the authors divided the study area into Kazakhstan and Tarim plates, and the two plates are connected by Late Paleozoic suture zone of southern Tianshan. Then the study area was further divided into five secondary units and eighteen third-level units. The results show that the northern, middle and southern Tianshan tectonic frameworks are continuous in the study area and the continental blocks were split at 800 Ma (equivalent to the bottom of Nanhua), which become parts of the Neoproterozoic Rodinia supercontinent. Later, the study area has experienced roughly the same structural evolution. From the beginning of the Middle Permian, the area transferredin to continental basin-mountain tectonic pattern. In Cenozoic, the collision between subcontinent of India and Eurasia has improved the continental basin-mountain tectonics pattern.