{"title":"Seismic 1/f Fluctuations from Amplitude Modulated Earth’s Free Oscillation","authors":"Akika Nakamichi, Manaya Matsui, Masahiro Morikawa","doi":"10.7566/jpsj.93.024004","DOIUrl":null,"url":null,"abstract":"We first report that the seismic time-sequence data from around the world, excluding major earthquakes, consistently yield the power spectral density inversely proportional to the frequency <i>f</i>. This is the 1/<i>f</i> fluctuation that appears ubiquitously in nature. We investigate the origin of this 1/<i>f</i> fluctuation based on our recent proposal: 1/<i>f</i> noise is amplitude modulation and demodulation. We hypothesize that the amplitude modulation is linked to resonance with Earth’s Free Oscillations (EFO), with demodulation occurring during fault ruptures. We provide partial validation of this hypothesis through an analysis of EFO eigenmodes. Additionally, we outline potential methods for the future verification of our theory relating 1/<i>f</i> fluctuations to EFO.","PeriodicalId":17304,"journal":{"name":"Journal of the Physical Society of Japan","volume":"8 1","pages":""},"PeriodicalIF":1.5000,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the Physical Society of Japan","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.7566/jpsj.93.024004","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
We first report that the seismic time-sequence data from around the world, excluding major earthquakes, consistently yield the power spectral density inversely proportional to the frequency f. This is the 1/f fluctuation that appears ubiquitously in nature. We investigate the origin of this 1/f fluctuation based on our recent proposal: 1/f noise is amplitude modulation and demodulation. We hypothesize that the amplitude modulation is linked to resonance with Earth’s Free Oscillations (EFO), with demodulation occurring during fault ruptures. We provide partial validation of this hypothesis through an analysis of EFO eigenmodes. Additionally, we outline potential methods for the future verification of our theory relating 1/f fluctuations to EFO.
期刊介绍:
The papers published in JPSJ should treat fundamental and novel problems of physics scientifically and logically, and contribute to the development in the understanding of physics. The concrete objects are listed below.
Subjects Covered
JPSJ covers all the fields of physics including (but not restricted to)
Elementary particles and fields
Nuclear physics
Atomic and Molecular Physics
Fluid Dynamics
Plasma physics
Physics of Condensed Matter
Metal, Superconductor, Semiconductor, Magnetic Materials, Dielectric Materials
Physics of Nanoscale Materials
Optics and Quantum Electronics
Physics of Complex Systems
Mathematical Physics
Chemical physics
Biophysics
Geophysics
Astrophysics.