河南及邻区中等地震前广义时间维的变化特征

• 作 者: 马俊林 谢智 王文旭 李廷栋
• 机 构: 河南省地震局!郑州，450000,河南省地震局!郑州，450000,河南省地震局!郑州，450000,河南省地震局!郑州，450000
• 出 处: 华南地震
• 发表日期: 1997年04期
• 关键词: 中等地震 时间维 中小地震 地展预报 邻近地区 降维过程 小震活动 震中区 中强地震 分维值

应用广义时间分维理论，对河南省及邻区1970年以来发生的12次ML≥4．7级地震前后的中小地震活动进行了时间扫描，分析其变化特征。结果表明，在研究区内发生的这12次中等地震前1～2年内，震中区及其邻近地区的广义时间维Dt都存在一个较为明显的降维过程；地震大多发生在Dt下降后开始恢复的过程段内；其发展时间大约距Dt异常最低点2～20个月；地震发生后Dt值常快速回升，并逐渐恢复正常。

The generalized time fractal theory is applied to time-scan the small and medium-sized seismic activities before and after 12 ML ≥ 4.7 earthquakes that occurred in Henan Province and its neighboring areas since 1970 and to analyze the variation characteristics. The results show that there is a significant dimensionality reduction in the generalized time dimension Dt in the epicentral region and its adjacent areas within 1-2 years prior to the 12 moderate earthquakes that occurred in the study area. Most of the earthquakes occurred after Dt decreased and then recovered . The development time is about 2 to 20 months from the lowest point of Dt anomaly. After the earthquake, the Dt value often rises rapidly and gradually returns to normal.