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依据走滑断裂的运动学和年代学 ,确认滇西腾冲地区新生代大型走滑断裂带变形作用的三个阶段 :1 )始新世初 (54— 56Ma) ,在槟榔江两岸出露的与新特提斯俯冲和两大陆碰撞相关的左旋走滑 -逆冲断裂 ,由此推断腾冲地块西缘南北向展布格局是两大陆碰撞后发生顺时针旋转达 90°的结果。2 )渐新世 -中新世 ,腾冲地块东缘的高黎贡右旋走滑断裂和西缘的那邦右旋走滑断裂存在两个走滑活动的峰期 :2 4 - 1 9Ma和 1 1 - 1 4 Ma,早期与 Tapponnier模式中挤出块体东边界红河 -哀牢山左旋走滑断裂活动的时限相一致 ,指示高黎贡和那邦右旋走滑断裂在此时期是挤出的印支地块的西边界 ;晚期与安达曼海的扩张、缅甸境内实皆断裂的右旋活动相一致 ,可能是此期地块再次发生挤出的结果。3)中新世末 ,约 5- 8Ma间两大陆的进一步会聚 ,引起了腾冲地区岩石圈结构的重要变化 ,腾冲地块发生了向南的挤出和顺时针的旋转 ,促成了一系列与此前右旋走滑相关的盆地的折返和南北向凹陷盆地的形成 ,制约了腾冲火山岩的喷发和整个地区的快速抬升。腾冲地块及其周缘新生代断裂带多阶段运动的转换对揭示青藏高原东南部块体运动型式具有重要的研究意义。
Based on the kinematics and geochronology of strike-slip faults, three stages of the deformation of the large Cenozoic strike-slip faults in the Tengchong area in western Yunnan were identified: 1) During the early Eocene (54-56 Ma) The Neo-Tethys subducted the left-lateral strike-slip-thrust associated with the collision between the two continents. It was concluded that the north-south spreading pattern on the western margin of the Tengchong block was the result of a clockwise rotation of 90 ° after the collision between the two continents. 2) Oligocene-Miocene, two strike-slip events occurred during the right-lateral strike-slip fault of the Gaoligong on the eastern margin of the Tengchong massif and that of the Nambon strike on the western margin: 2 4 - 1 9Ma And 11-1 4 Ma, consistent with the time limit of the left-lateral strike-slip faulting of the Red River-Ailao Mountain in the east boundary of the extruded block in the Tapponnier model in the early stage, indicating that the dextral strike-slip faults at Gaoligong and Nabang are The western boundary of the extinct Indosinian massif is the same as the extension of the Andaman Sea and the right-lateral rotation of the Saga fracture in Myanmar, which may be the result of the re-extrusion in this period. 3) At the end of the Miocene, the further convergence of the two continents, about 5-8 Ma, caused an important change in the lithospheric structure in the Tengchong area. The southward extrusion and clockwise rotation of the Tengchong block led to a series of changes The reentrancy of the basin associated with the dextral strike-slip and the formation of the north-south sag basin constrain the eruption of the Tengchong volcanic rock and the rapid uplift of the entire area. The multi-stage movement transformation of the Tengchong block and its peripheral Cenozoic fault zone has important research significance for revealing the block motion pattern in southeastern Qinghai-Tibet Plateau.