关键词: 断层形变, 小波分析, 多尺度熵, 异常, 新疆

Abstract: Information extraction and analysis about cross-fault deformation is one of the important contents in earthquake research. Based on the theory of wavelet analysis and information entropy,the wavelet multi-scale entropy that describes the ordering degree in local data has been proposed in this paper. We studied the wavelet multi-scale entropy variation characteristics before strong earthquakes and the relationship between decreasing entropy anomaly and the three elements of earthquake by using the cross-fault fixed deformation data from Tianshan area in Xinjiang. The results indicate that:the amount of information of high frequency component is more than that of low frequency in cross-fault deformation rate,and a decreasing entropy anomaly appears before most of strong earthquakes. Furthermore,the logarithm of cumulative decreasing entropy is obviously linear with magnitude and the time from the beginning of anomaly to the occurrence of earthquake. If the magnitude is larger,the time from the beginning of anomaly to earthquake will be longer,and the cumulative decreasing entropy will be larger. Finally,the association is obvious between the integral decreasing entropy of multiple stations and large range crustal movement and the seismic active period.

Key words: fault deformation, wavelet analysis, multi-scale entropy, earthquake anomaly, Xinjiang