门源M_(S)6.9地震前前兆吸引子的特征提取  

Feature Extraction of Earthquake Precursory Attractor before the Menyuan M_(S)6.9 Earthquake

作　　者：张海玲 ZHANG Hailing(Lanzhou Geophysics National Observation and Research Station,410 West-Donggang Road,Lanzhou 730000,China)

机构地区：[1]兰州地球物理国家野外科学观测研究站,兰州市730000

出　　处：《大地测量与地球动力学》2024年第12期1250-1255,共6页Journal of Geodesy and Geodynamics

基　　金：甘肃省地震局地震科技发展基金(2022Q01)。

摘　　要：以非线性动力系统为理论依据类比地震孕育过程,以非线性动力系统的吸引子理论类比研究地震前兆吸引子,将高台台钻孔倾斜定点形变观测作为孕震系统的状态变量,借助G-P算法从宏观观测数据入手推演前兆动力学特征。在验证了以钻孔倾斜作为状态变量时非线性动力系统前兆吸引子存在的基础上,通过研究以NS、EW分量作为状态变量时吸引子维数的变化特征,归纳总结出门源M_(S)6.9地震前出现异常的NS分量对应的前兆吸引子存在降维特性,即在震前随着时间推移和三维重构相空间数据分布变得集中而有序,相应的地震前兆吸引子的分形维数也更低;而在震前未出现异常的EW分量对应的前兆吸引子的分形维数则保持不变,且其三维重构相空间中点的分布也无明显差异。Based on the theory of nonlinear dynamic system,we simulate the process of earthquake preparation.We then use the attractor theory of nonlinear dynamic system to study the precursory attractor of earthquake by analogy,and use the borehole inclination at Gaotai station of fixed-point deformation observation as the state variable of the seismogenic system.The precursor dynamics characteristics are deduced from the macroscopic observation data with the help of G-P algorithm.On the basis of confirming the existence of precursory attractor of nonlinear dynamical systems with borehole inclination as state variable,by studying the change characteristics of the attractor dimension when NS and EW components are used as state variables,we conclude that the precursor attractor corresponding to the abnormal NS component before the Menyuan M_(S)6.9 earthquake has dimensionality reduction characteristics,that is,the more concentrated and orderly the distribution of 3D reconstructed phase space data before the earthquake,the lower the fractal dimension of the corresponding seismic precursor attractor.However,the EW component that does not appear abnormal before the earthquake is in different order,the fractal dimension of the corresponding precursor attractor remains unchanged,and the distribution of points in the 3D reconstructed phase space has no obvious difference.

关 键 词：非线性动力系统 混沌 前兆吸引子 分形维数 G-P算法 

分 类 号：P315[天文地球—地震学]