1976年黑山、砣矶二次震群多分形特征研究

THE MULTIFRACTAL CHARACTERISTICS OF HEISHAN AND TUOJI EARTHQUAKE SWARMS IN 1976

依据“固定半径法”的定义及原理，对1976年黑山、砣矾震群的时间结构的广义维数Dq-q和标度指数谱f（α）-α曲线的特征进行了初步研究。结果表明二次前兆震群表现出各自的特征，即砣 震群地震时间多分形结果出现剧变型异常，其表征为q为负值时Dq增大，q为正值时Dq减小且变化幅度大。与此同时，f（α）两端下降，α跨度也较大。而黑山震群地震时间多分形结构没有出现明显异常，Dq-q曲线平缓，f（α）-α谱曲线跨度较小。对两者差异的原因进行了讨论。

Based on the principle of the 'fixed radius method' , the temporal characteristics of Dq-q and f(α)-α spectra of the Heishan and Tuoji earthquake swarms have been preliminarily stud-ied. The results show that two precursory swarms have different abnormal features. For Tuoji earthquake swarm , the value of Dq increases when q <0 and Dq value decreases when q >0.Meanwhile, the changing range of Dq value is wide and two ends of f(α) curve drop down, and the numerical distribution range of index a becomes wider and wider. The obvious abnormal precursors can not be found from temporal multifractal structure for Heishan earthquake swarm. The change of Dq-q curve is not obvious and distribution range of f(α)-α spectra is small. The reason of the difference between two earthquake swarms is also discussed in this paper.