Earth's background free oscillations

被引：146

作者：

Suda, N ^{[1
]}

Nawa, K

Fukao, Y

机构：

[1] Nagoya Univ, Dept Earth & Planetary Sci, Nagoya, Aichi, Japan

[2] Univ Tokyo, Earthquake Res Inst, Tokyo 113, Japan

来源：

SCIENCE | 1998年 / 279卷 / 5359期

关键词：

D O I：

10.1126/science.279.5359.2089

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Earth's free oscillations were considered to be transient phenomena occurring after large earthquakes. An analysis of records of the IDA (International Deployment of Accelerometers) gravimeter network shows that Earth is freely oscillating at an observable level even in seismically inactive periods. The observed oscillations are the fundamental spheroidal modes at frequencies between 2 and 7 millihertz. Numerical modeling indicates that these incessant excitations cannot be explained by stacked effects of a large number of small earthquakes. The observed "background" free oscillations represent some unknown dynamic process of Earth.

引用

页码：2089 / 2091

页数：3

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