2017 Fiscal Year Final Research Report
Ambient seismic wavefield: Atmosphere-Ocean-Solid Earth Coupling
Project/Area Number |
26400448
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Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Solid earth and planetary physics
|
Research Institution | The University of Tokyo |
Principal Investigator |
|
Project Period (FY) |
2014-04-01 – 2018-03-31
|
Keywords | 常時地球自由振動 / 海洋波浪 / 海洋外部重力波 / 脈動 |
Outline of Final Research Achievements |
We analyzed globally distributed 700 broad band seismometers, and revealed the source characteristics of seismic hum. In a period from 10 to 200 s, seismic hum was excited through a topographic coupling between external ocean wave and seismic waves, whereas in a period longer than 200 s, atmospheric and/or ocean disturbances could also contribute the excitation. Moreover we inferred source distribution by analyzing body-wave microseisms with period shorter than 10 s. Based on all the observations, we showed the excitation mechanisms comprehensively.
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Free Research Field |
地震学
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