Abstract: The characteristics of seismic water-level fluctuations of the two Sumatra-Andeman strong earthquakes with magnitude 8.7 and 8.5 on December 26,2004 and March 29,2005 recorded at Jiaji station,Qionghai,Hainan were analyzed,the features of the infreguent "terrace" changes of the well water-level after the two earthquakes also were analyzed,the mechanism of "terrace" of the well water-level changes has been primarily discussed.Then the digital observation information with high sample ratio of the Sumatra-Andeman strong earthquakes with magnitude 8.7 and 8.5 at Nanbin station,Sanya and Tanniu station,Wenchang was analyzed.The results suggest that the dominant period of the seismic wave of well water-level at the two wells was comparatively accordant,the amplitudes of seismic water-level fluctuations of the same earthquake at the two wells were clearly different,the time duration of seismic water-level fluctuations of different earthquakes at the same well was also clearly different.

Key words: Sumatra-Andeman strong earthquake, digital records of well water level, coseismic response, Hainan area

摘要： 分析了琼海加积井在苏门答腊M_S8.7和M_S8.5地震时水震波特征及震后出现的水位阶变特征,初步探讨了水位阶变现象的机理。同时还分析了三亚南滨井、文昌潭牛井在苏门答腊M_S8.7和M_S8.5地震时水震波的高采样率数字化观测资料,结果显示:3口井的水震波优势周期比较一致,同一地震在不同井孔的水震波幅度差别较大,同一井孔不同震级地震的水震波振荡持续时间不同。

关键词: 苏门答腊大地震, 数字化水位记录, 同震响应, 海南地区