龙门山重力滑脱作用形成挤压性构造的物理模拟实验

摘要

研究龙门山构造带在晚印支早期阶段的构造动力学作用机制,以及在此机制下的重力滑脱作用形成局部挤压环境的可能性.通过以重力为动力的构造物理模拟实验研究,表明在板内的差异隆升背景下可以导致重力滑脱作用发生,在重力滑脱作用下在滑脱体前缘形成挤压性构造变形可能性是存在的.结合龙门山构造带前人的研究资料和国内外近年相关研究成果,龙门山构造带的形成过程可能是在晚印支早期历经了拉张性构造环境后叠上冲推覆过程,从而形成现今的构造格局.%The paper studies the mechanism of the tectonic dynamics in forming the Longmenshan structural belt in the early stage of the late Indo-Chinese epoch and the possibility of forming the local compressive environment. Through the simulation experiment in which the main power is gravity, it indicates that gravitational sliding can emerge under the background of differential upheaval in the plate and there exists the possibility of forming a compressional structure in the front of the sliding body. Combined with the data of previous researches and the achievements in this aspect at home and abroad, the formation of the Longmenshan tectonic zone is considered to be the stacked thrusting process after experiencing the extensional structure. Thus, the present structural pattern has formed in the Longmenshan zone.