台湾地区地震活动的时间多分形特征研究

Study of Temporal Multifractal Characteristics of the Seismic Activities in Taiwan Region

利用板块构造、活断层分布、地壳运动这三个方面的最新资料将台湾地区划分为东、西两个地震区和六个地震带。对各地震带 11a来的地震目录计算了广义维数Dq 和多标度分形谱f (α) ,然后绘制成Dq—q曲线和多标度分形谱f (α)—α以及分维时程曲线。综合分析后发现 :(1)地震活动的时间结构是多分形而非单一分形结构 ;(2 )台湾地区在大震前后的 1～ 2a内 ,大震所在的地震带内地震时间结构的Dq—q曲线和多标度分形谱f (α)—α大都出现异常形态 ;(3)Dq 时程曲线分析可以为强震的时间预报提供有效的客观依据。

Through the analysis of plate tectonics, the distribution of active faults and crustal movement, the Taiwan Region is divided into two seismic regions and six seismic belts. Using the earthquake catalog of Taiwan Region in 11 years, the aulthor calculated the multifractal dimensions D_q and f(a) of six seismic belts respectively. Then D_q-q curves, multiscale fractal charts f(a)-a and D_q-t curves are plotted. After integrated analyses, the following conclusions are drawn: (1) the temporal structure of earthquakes is not single fractal but multifractal; (2) within 1-2 years before and after a major earthquake in Taiwan, an abnormal shape appeared for most of D_q-q curves and f(a)-a plots in each seismic belt where the earthquake occurred; (3) the pattern of D_q-t curves is a good indicator for the time prediction of strong earthquake events.