基于HHT提取昆明、下关重力固体潮的地震前兆信息  

The gravity tide of Kunming & Xiaguan based on the HHT

作　　者：周挚[1] 山秀明[2] 张立[3] 傅容珊[3] 梁虹[4] 全海燕[5] 

机构地区：[1]云南省地震局,昆明650224 [2]清华大学电子工程系,北京100084 [3]中国科技大学地球和空间科学学院,合肥230026 [4]云南大学信息学院,昆明650091 [5]昆明理工大学信息工程与自动化学院,昆明650051

出　　处：《地球物理学报》2008年第3期836-844,共9页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(40774032);“十五”国家科技攻关项目(2004BA601B01-01-04);云南省自然科学基金项目(2003D0084M)资助

摘　　要：在重力固体潮地震前兆分析中引入HHT时频分析新方法.结合HHT的优越性、固体潮的特点和地震的非平稳过程特性,设计重力固体潮地震前兆分析的瞬时频率特征参数;以相应理论计算值作为参照背景,研究固体潮的震前变化特征.昆明、下关的震例分析表明,的确存在瞬时频率特征参数的震前变化,且具短期、同步正异常特征;瞬时频率特征参数具有明确的物理意义,其震前变化反映了地震非平稳过程对理论重力固体潮的影响.HHT time-frequency method is introduced in new analysis of gravity tide. Based on superiority of HHT, the character of gravity tide and nonstationary processes of earthquake, we design characteristic parameters of instantaneous frequency of gravity tide. And we refer to corresponding theoretical values of gravity tide in the course of earthquakes analysis. The results of Kunming and Xiaguan show that there are some premonitory changes in the characteristic parameters of instantaneous frequency before earthquakes, which bear short-term and synchronization characters. The characteristic parameters of instantaneous frequency have clear physical significance. These premonitory changes express that the nonstationary processes of earthquake influenced the observation of stationary processes of gravity tide.

关 键 词：重力固体潮 HHT 瞬时频率 地震前兆 

分 类 号：P315[天文地球—地震学]