Abstract：We analyze the earth's free oscillation induced by the M9.0 earthquake off the east coast of Japan, using data observed with the DZW gravimeter at China's 14 observatory stations, and the 2D and 3D time frequency characteristics are displayed for the first time. Comparing the spectrum figures of the 14 observatory stations, we found that the energy of the earth free oscillation is uniformly distributed in the frequency axis, and shows frequency information clearly. However, there are differences in the time axis, the distribution of the energy of the earth free oscillation is similar at most stations, but narrower at the Yichang, Xichangxiaomiao, Xiamen and Shenzhen stations.
JIN Dali,LI Ruidong,FAN Chunyan et al. The Time Frequency Analysis of the Earth’s Free Oscillation Induced by the
M9.0 Earthquake in East Japan Observed with the DZW Gravimeter[J]. jgg, 2015, 35(3): 529-532.
