【摘要】 天山造山带南北分别于塔里木盆地和准噶尔盆地相接,经历古生代时期超级大陆裂解、南北天山洋裂开、洋盆持续扩张、洋壳俯冲消减、陆陆碰撞缝合过程及中新生代陆内再造山构造调整,是现今世界上较为活跃的陆内造山带,成为国内外大陆动力学研究的热点地带.在综合分析地质学、地球物理(地震剖面、重力异常、地震层析)、地球化学、岩石学及天文学等资料基础上,结合天山造山带大地构造演化历史、地表构造变形、盆地基底构造样式,以及对5种地幔对流模式的深入探究,基于全地幔对流和上地幔小尺度对流模式,提出天山地区板块构造演化与地慢对流的耦合动力机制,总体呈现为"启动同步超越消减"模式,中间过程则伴随微观振荡旋回动力模式向前发展,该模式可与经典威尔逊旋回比较,同时现今地球深部板块演化痕迹及地幔对流数值模拟一定程度上支持了该模式.总之,将板块构造演化历史与地幔对流结合起来、纳入统一的动力学模型中,对于今后研究地球各子系统之间的耦合状态、相互作用有十分重要的意义.更多还原

【Abstract】 Tianshan orogenic belt connects with the Tarim basin and Junggar basin from south to north respectively. Through a joint Paleozoic continental breakup,the South Tianshan Ocean and the North Tianshan ocean cracked,the continued expansion of ocean basins,oceanic crust subduction,continental collision and suture and Cenozoic tectonic adjustments,now it is the world’s more active orogenic belt and become a domestic hot zone of continental dynamics. Based on comprehensive analysis of geological,geophysical(seismic profiles,gravity anomalies,seismic tomography),geochemical,petrological,and astronomy,etc.,combined with the tectonic evolution history of the Tianshan orogenic belt,the surface structural deformation,base tectonic style of the basin,and the deeply inquiry of the five kinds of mantle convection patterns,based on whole-mantle convection and small-scale upper mantle convection model,we propose that the dynamic mechanism of plate tectonic evolution coupled with the mantle convection in the Tianshan region totally presented as "Start-Sync-Transcendence-Subtractive" mode,and the middle course of the dynamic model with micro-oscillation cycle forward.This model can be compared with the classic Wilson cycle,while the current traces of the plate tectonic evolution in the deep crust and the numerical simulation of the mantle convection also supports this mode to some extent.In short of a unified dynamic model comhing the history and evolution of plate tectonics and mantle convectton,it will be of great significance for future study of coupling and interaction between all the subsystems of the Earth.更多还原