期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1981
卷号：78
期号：1
页码：20-21
DOI：10.1073/pnas.78.1.20
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The effect of changes in gravity induced by the Earth's deformation on seismic recording at ultralong periods is studied quantitatively for the low-order spheroidal modes of the Earth. Because this effect can either enhance or reduce the recorded amplitude of a mode, depending on its geometry, it may become nontrivial at the longest free-oscillation periods, and contribute to relative deviations of up to 17%.
关键词：seismology ; normal modes ; theoretical geophysics
