【摘要】 基于形变数字化观测资料,利用功率谱密度估计方法,在没有对易县形变综合观测资料进行任何(固体潮及气压)改正的情况下,获取了2011年3月11日日本发生巨大地震激发的0S4～0S37基频球型自由振荡。并于PREM模型理论自由振荡的周期进行对比分析,得出实测周期与PREM预测振荡周期是相吻合,除0S10周期的相对误差为0.29%,其余周期误差均小于0.1%左右。所得的结论对进一步研究地球的内部结构和震源机制具有一定的意义。更多还原

【Abstract】 Using power spectral density method based on digital deformation data without any correction,this paper get spherical free oscillation from 0S4~0S37 caused by Japan earthquake in March 11th,2011.Compared with cycle of free oscillation by PREM model,the results showed practical cycle is match up with estimation while each error is lower than 0.1% except 0S10 cycle with 0.29%.The conclusion is meaningful to study on inside structure of earth and focal mechanism.更多还原