Numerical Simulation of Relationship between Stress Field Evolution and Historical Strong Earthquakes in Taiyuan Basin
Li Ping'en
Liao Li
Liu Pan
Abstract：In recent years,although no strong earthquakes occurred in Taiyuan basin,small earthquakes were very active.However,the research on the distribution and evolution of tectonic stress field in Taiyuan basin is very little.The 3-D viscoelastic finite element model of Shanxi area including Taiyuan basin is built by applying the finite element numerical method in this paper.In addition,the difference of regional geological structure,the main active fault zone,irregular topography and layered lithosphere structure synthetically,as well as the seismic velocity structure of the crust and mantle,are considered when building the model.Moreover,the present tectonic background stress field in the research area is reconstructed by the constraint of the observed values of GPS and direction of the maximum principal compressive stress.On these bases,the historical strong earthquake sequences with M≥6 in Taiyuan basin and with M≥7 in Shanxi seismic zone since AD 512 are simulated,respectively.The calculated results illustrate that the three historical strong earthquakes in Taiyuan basin are all located in the area where stress field increased more than 0.01 MPa,and the spatial distribution of small earthquakes in recent years has a good correlation with the present stress field change greater than 0.01 MPa.The results show that the historical strong earthquake sequence in Shanxi seismic zone and long-term tectonic stress loading both promoted the three historical strong earthquakes in Taiyuan basin.The present seismic activity of Taiyuan basin is obviously controlled by the current stress level in the area.
Keywords：Taiyuan basinstress filed evolutioninteraction between strong earthquakesseismic activitynumerical simulation
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：14( 1623-1636 )