Simulation Study On Multistage Deformation Of Superimposing Process

Through the comprehensive analysis of the regional plate tectonic environment,seismic section interpretation results and tectonic physical simulation results,it can be concluded the structural characteristics of Bohai Bay Basin are divided into stages and the factors of basin formation are different.In this paper,11 sections running through the whole area have been restored,and combined with more than 150 domestic and foreign literatures,systematic statistics of extensibility,analysis of subsidence and experiment of four equal proportion models have been carried out in the Bohai Bay Basin.North to east right strike slip mode respectivelyNW-SE extensional superimposed NNE strike slip model.The NW-SE extension superimposed near the NNE extension model was verified,and finally put forward the counter-clockwise rotation mode of the stage-the NW-S-E extension superimposed near north-north extension superimposed rotation model.During the Ek-Es₄ sedimentary period,the Bohai Bay basin experienced the NW-SE extensional deformation and formed the NE-trending extensional fault.During the Es₃-Ed sedimentary period,the basin experienced the nearly north-south extensional deformation,and formed a near-east-west extensional fault in the central area.During the Ng-Nm sedimentary period,the basin experienced local inversion and formed part of the thrust fault in the Liaodong Bay-Lower Liaohe area.The basin was mainly extensional in the Cenozoic,and in the late Oligocene,due to the confluence of the Pacific plate and the Eurasian plate,the basin rotated counterclockwise in the eastern part of the Bohai Bay basin.The inversion structure is formed in the NNE direction of the Tan-Lu fault zone.