球形地球模型的地震位错理论及其应用

Seismic dislocation theory of spherical Earth model and its application

地震位错理论是研究地震断层滑动与地球物理场变化之间关系的理论,是震源机制、地球内部构造、地震预测等基本地球物理问题与大地测量、地球物理观测数据之间的联系纽带。被广泛使用的半无限空间介质模型的位错理论,由于其几何模型的限制,在地震变形和地球动力学等应用研究中会导致一定程度的误差。此外,现代大地测量技术可以在全球和区域尺度上精确地观测地震变形,亟需一个适用于全球地震变形研究的地震位错理论。为此,本团队基于球形地球模型,经过多年系统性研究,建立了地震位错理论新体系。所构建的球形地球模型的地震位错理论,促进了全球地震变形和地球动力学变化的研究,是近年来地球物理学领域取得的重要理论进展之一。本文简要地介绍了国内球形地球模型地震位错理论的发展及其应用研究。首先,介绍了弹性球形地球模型、三维不均匀地球模型和黏弹地球模型的位错理论;其次,介绍球形地球模型的位错理论在地球动力学变化研究、断层与地下介质结构反演和地震大地测量学研究方面的相关应用;最后,对球形地球模型的位错理论的发展方向作出展望。

Seismic dislocation theory is the theory of studying the relationship between seismic fault slip and geophysical field change,and also it is the link between the source mechanism,the internal structure of the Earth,earthquake forecasting and other basic geophysical problems and geodetic-geophysical observation.The widely used dislocation theory of the semi-infinite medium model,due to the limitation of its geometric attribute,will riskily result in a certain degree of oversight and even fault in the application of seismic deformation and geodynamics analysis.In addition,modern geodesy technology can accurately observe seismic deformation on global and regional scales,and a suitable seismic dislocation theory born for global seismic deformation study is urgently required.For this purpose,our team has developed a new system of seismic dislocation theory based on the spherical Earth model through many years of systematic research.The establishment of such theory has promoted the study of global seismic deformation and geodynamic process,and expanded the study of earthquake-induced global geodynamic changes.This informative article briefly introduces the domestic development and application of seismic dislocation theory of spherical Earth model.The first section introduces the dislocation theory of elastic spherical Earth model,three-dimensional inhomogeneous Earth model and viscoelastic Earth model.The second section introduces the relevant applications of the dislocation theory of spherical Earth model in geodynamic change,fault and underground structure inversion and others in seismological geodesy.The seismic dislocation theory of the spherical Earth model has promoted the study of global seismic deformation and geodynamic changes.It is one of the important theoretical advances in the field of geophysics in recent years.