Evaluation And Analysis Of Active Faults And Regional Tectonic Stress Field Of Hebei Plain

Hebei Plain is one of severe earthquake places in China, and it is famous for its Seismic and Geological hazards. Since 1949 there have taken place three earthquakes whose Ms are all up to 7.0,in particular the Tangshan Earthquake (Ms=7.8 ) which took place in 1976 and nearly 240000 people died in this hazard. Along with the quick development of economy and science, it is vital to entirely evaluate the Geological environment and the stability of Crust, forecast the impact which is from the reaction between the Geological Environment and Engineering Construction and economic development, prevent and control the geological hazards in order to make well use of field.The Evaluation and Analysis of Active Fault and Regional Tectonic Stress Field is one of important parts of Analysis and Evaluation of Crust Stability. And Seismic activities, active faults, volcanic activities play great role in the Analysis and Evaluation of Crust Stability.Based on analyzing previous datum and reviewing active faults in point, and using subsection and fractal and fractal dimension to analyze the area, getting the fractal dimension of NE is 1.77,the fractal dimension of the direction of latitude is 1.41, the average fractal dimension of the area is 1.68, and the datum are higher than the active faults system of Japan and the fractal dimension of the northwest of Sichuang and Guizhou, the high fractal dimension is consistent with so many earthquakes and Geological hazards. At the same time making the conclusion that the Cangdong fault is not an active fault and is a shovel fault and is not possible for this fault to cause severe earthquakes. The Seismic strip of Tangshan-Hejian -Shexian has same Tectonic Stress Field and the Seismic Mechanism Solutions are nearly identical, and it is a sheared moving zone of Crust Fracture ,but it is not successive, it is made up of series faults.In this paper, using the measured datum of Stress, the Seismic Mechanism Solutions and the numerical stimulation by the Finite Element Method to analyze the Tectonic Stress Field. The Tectonic Stress is the prime impulsion of the Crust movement and distortion. And finding that the focus area of stress is corresponding to the dense area of earthquakes, which shows the Geological Model is reasonable and...