Physical Modeling Research Of The Cenozoic Salt Tectonics Evolution Process In The Western Kuqa Depression

The Kuqa Depression located in the northern Tarim Basin in the northwestern part of China,and there are abundant salt-related structures in the western Kuqa depression.Salt tectonics play an important role in the generation,accumulation of oil and gas in saltbearing basins.Therefore,understanding the deformation evolution process of the Cenozoic salt tectonics in the western Kuqa depression has important guiding significance for the exploration of oil and gas in this area.In this paper,based on previous studies on the Cenozoic salt tectonics in the western Kuqa depression,seismic profiles and logging data are used to establish scientific geological models and carried out physical modeling experiments to study the deformation evolutionary process of the Cenozoic salt tectonics comprehensively,the main results are as follows:(1)The salt diapir structure developed early in the Cenozoic in the western Kuqa depression is the main reason for the formation of current tectonic framework in the western Kuqa depression.The early salt diapir is the area where stress is preferentially released during extrusion.In the extrusion process,the fold deformation occurs first,and finally it can evolve into a salt nappe,salt withdrawal minibasin and salt welding were fomed as well;(2)Multiple factors will affect the evolution of the early salt diapir.The presence of basement slopes helps to form salt shrouds and salt weld structures during the early stage of salt diapir in the later extrusion process.Deformation evolution also has important influence;(3)The extrusion rate has a significant effect on the deformation evolution of fault folds and early diapir.Higher extrusion rate will increase the dip angle of thrust faults developed in the fault fold zone,reduce the deformation range,and deform the salt withdrawal minibasin in the overburden,resulting in no further uplift of the fault fold zone.At the same time,the deformation of the salt shroud is slowed and the pushing distance is reduced.