Structural Characteristics Of Shiling Section Of Jia-Yi Fault Zone

The jia-yi fault zone is an important part of the northern part of the tanlu superlithospheric fault zone in China.It also plays an important role in detecting and preventing Mesozoic and Cenozoic magma activity,mineral distribution and seismic activity.Due to the large dynamic background of the tanlu fault zone,the shiling section of the jia-yi fault zone underwent multiple tectonic processes such as strike-slip,tensioning,basement uplift and compression inversion,resulting in very complex structural features and evolution of the shiling region.However,due to its geographical location,geological environment and other factors,there have been few studies on the tectonic str ess characteristics of the studied area,and most of the current achievements are based on geophysical means to study the regional seismic distribution or focal mechanism,which greatly restricts the in-depth study on the fault nature,structural characteristics and evolution of the area.Based on the above reasons,this paper combines the latest geological data and research results,starts from the regional tectonic deformation characteristics of shiling area through field geological foundation survey,takes the structural profile across the research area as a supplement,and applies the analysis of tectonic stress field to make an overall discussion on the structural system characteristics and deformation genesis mechanism of this area.Through tectonic geology,tectonic analysis and plate movement,the sedimentary construction,deformation and metamorphism and deep structure in the area are discussed.Preliminary analysis of the characteristics and movement mechanism,boundary faults through inversion to infer the formation stress,as well as by the environment and follow similar principles,the characteristics of regional structure,geometry,kinematics characteristics in-depth study,on the whole divided into the structure of the big issue,in order to find out the spatial distribution of the segment structure characteristics,distribution characteristics,and tries to explore the northern section of tanlu fault and even in eastern China in the meso-cenozoic tectonic movement.Through this study,the author basically identified the main structural features in the region,and the main research results are as follows: 1.The structure and main stress in the shiling region are mostly nw-se compression,and the fault structure is mostly sinistral strike slip.2.The distribution law of joints in shiling area was predicted,among which,the northeasterly joints were the most developed,accounting for more than half of the joints in this area,followed by the northeasterly joints.The main stress direction of the structure is mostly nw-se compression,and the fault structure is mostly sinistral strike slip.3.According to the interpenetration of various structural trace characteristics in shiling area,the relative order of their formation can be inferred: late late Jurassic cataclastic granite--shear deformation--tensioning--light-colored dyke--ductile deformation--dark dyke--strike-slip thrust sequence.4.It is found through the study that there are both extensional structural features and extrusion and strike-slip structural features in this region,and strong strike-slip events occurred in this region at the end of Mesozoic,which have the same structural properties as the middle-south strike-slip and strike-slip events.