This paper presents new estimations for all parameters(amplitude,frequency,quality factor,and initial phase)of the_(0)S_(0)Earth fundamental mode,which was triggered by the 2004 Sumatra-Andaman earthquake with a magni...This paper presents new estimations for all parameters(amplitude,frequency,quality factor,and initial phase)of the_(0)S_(0)Earth fundamental mode,which was triggered by the 2004 Sumatra-Andaman earthquake with a magnitude of Mw9.1.Sixteen records from the IGETS superconducting gravimeters have been analyzed.Using the maximum likelihood method algorithm,frequency,initial phase,and amplitude estimates have been acquired with remarkable accuracy.The values of frequency(814.6568±0.0002μHz)and quality factor(5455±17)obtained in this study differ slightly from those of the PREM model,and the amplitude variations qualitatively correspond to those of the SKS12WM13model.The estimated time delay between the onset of the earthquake and the excitation of the mode(290 s)is consistent with the moment tensor analysis from the USGS National Earthquake Information Center.展开更多
基金conducted under the state assignment of Lomonosov Moscow State University。
文摘This paper presents new estimations for all parameters(amplitude,frequency,quality factor,and initial phase)of the_(0)S_(0)Earth fundamental mode,which was triggered by the 2004 Sumatra-Andaman earthquake with a magnitude of Mw9.1.Sixteen records from the IGETS superconducting gravimeters have been analyzed.Using the maximum likelihood method algorithm,frequency,initial phase,and amplitude estimates have been acquired with remarkable accuracy.The values of frequency(814.6568±0.0002μHz)and quality factor(5455±17)obtained in this study differ slightly from those of the PREM model,and the amplitude variations qualitatively correspond to those of the SKS12WM13model.The estimated time delay between the onset of the earthquake and the excitation of the mode(290 s)is consistent with the moment tensor analysis from the USGS National Earthquake Information Center.