Abstract：On the basis of the observations of SSY quartz extensometers at Guza and PanzhihuaNanshan stations in Sichuan province, the oscillation wave trains excited by the Sumatra Ms8.7 earthquake on December 26, 2004 in Indonesia，the Hokkaido Ms8.0 earthquake on September 26, 2003 in Japan and the Ms7.9 earthquake on September 27, 2003 on the borders of Russia, Mongolia and China were decomposed by wavelet transform and the spectrum analysis were done, and the analysis results were compared with the usual observation records. The time of oscillation waves excited by great farfield earthquake from SSY quartz extensometer observation data lags，several main frequency components of spectrum structure obtained by decomposing oscillation wave trains are in accordance with some modes of earth’s free oscillations.
Zhang Zhiwei ,Cheng Wanzheng ,and Ruan Xiang . ON OSCILLATION WAVES INDUCED BY GREAT FARFIELDEARTHQUAKE AND ITS SPECTRUM FROM SSY EXTENSOMETER DATA [J]. jgg, 2008, 28(5): 27-33.
