Scattering and intrinsic absorption parameters of Rayleigh waves at 18 active volcanoes in Japan inferred using seismic interferometry

Hirose, Takashi; Ueda, Hitoshi; Fujita, Eisuke

doi:10.1007/s00445-022-01536-w

Cited by 3 publications

(2 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(2016) reported that surface waves are predominant up to around eight times the transport mean free time. We assumed the transport mean free time at Suwanosejima to be roughly 2.2 s from the typical value of the scattering mean free path at other volcanic islands in Japan (Hirose et al., 2019, 2022). The used time window is shown by green‐dashed rectangles in Figure 2a.…”

Section: Methodsmentioning

confidence: 99%

“…In this study, we assumed that Rayleigh waves were predominant in seismic ambient noise CCFs and defined the end times of the window as 𝐴𝐴 𝐴𝐴2 = 𝐴𝐴1 + 15 s. Obermann et al (2016) reported that surface waves are predominant up to around eight times the transport mean free time. We assumed the transport mean free time at Suwanosejima to be roughly 2.2 s from the typical value of the scattering mean free path at other volcanic islands in Japan (Hirose et al, 2019(Hirose et al, , 2022. The used time window is shown by green-dashed rectangles in Figure 2a.…”

Section: Estimation Methods Of Seismic Scattering Property Changesmentioning

confidence: 99%

See 1 more Smart Citation

Seismic Scattering Property Changes Correlate With Ground Deformation at Suwanosejima Volcano, Japan

2022

Self Cite

View full text Add to dashboard Cite

Continuous estimation of changes in seismic velocity and seismic scattering property by passive interferometry using seismic ambient noise is a promising tool for monitoring volcanoes. To improve the usefulness of this method, it is necessary not only to detect subsurface structural changes but also to quantitatively compare the estimated changes in seismic wave velocity and seismic wave scattering property with other observations, such as ground deformation. We applied passive interferometry to continuous seismic records from the Suwanosejima volcano, Japan, recorded between April 2017 and December 2021. We detected repeated significant waveform decorrelations in seismic ambient noise cross‐correlation functions (CCFs), indicating changes in seismic scattering property in the shallow areas of the volcano. These decorrelations were observed from 2 weeks to a few days before the increase in the number of explosions, suggesting that seismic scattering properties changed significantly during that period. We found that the timing of the decorrelation in seismic ambient noise CCFs and tilt changes related to magma accumulation and injection beneath Suwanosejima were well synchronized. The high correlation between the amounts of decorrelation and the tilt change during the magma accumulation period possibly suggests that a large volume of accumulated magma caused great changes in the scattering property. These results provide a significant first step toward a quantitative comparison of the amount of changes in the scattering property with the amount of magma accumulation beneath volcanoes.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Estimation Methods Of Seismic Scattering Property Changesmentioning

confidence: 99%

Seismic Scattering Property Changes Correlate With Ground Deformation at Suwanosejima Volcano, Japan

2022

Self Cite

View full text Add to dashboard Cite

show abstract

Anisotropic seismic velocity variations in response to different orientations of tidal deformations

Takano,

Nishimura,

Nakahara

2023

Geophysical Journal International

View full text Add to dashboard Cite

Summary Micro-cracks or micro-pores in rocks cause the elastic moduli to change with the applied strain owing to the nonlinear elasticity of the geomaterial, which causes temporal changes in the seismic wave velocity. Thus, variations in seismic wave velocity can be used as a proxy for understanding the strain or stress variations in the crust, which are crucial for figuring out the dynamics of the fault zones and volcanic domains. According to the theory of nonlinear elasticity, the second- and third-order elastic constants and strain tensors contribute to the strain derivative of seismic wave velocity changes. Although laboratory experiments have estimated third-order elastic constants for rock samples, the in-situ values of those constants for the crust are difficult to obtain. In this study, seismic velocity changes were investigated in different directions of tidal deformations to provide constraints on the third-order elastic constants in the shallow crust by applying a seismic interferometry method to ambient noise records. We observed that negative velocity changes were of larger magnitude in the station-pair direction parallel to the tidal strain’s direction. Nonlinear elasticity in shallow crust may cause anisotropic velocity variations in response to tidal deformations. Our results highlight the use of velocity change measurements in different directions of tidal strain to constrain nonlinear elastic parameters on a field scale.

show abstract

Continuous monitoring of instrumental clock errors at 50 volcanoes in Japan based on seismic interferometry

Hirose

Ueda

2022

Preprint

Self Cite

View full text Add to dashboard Cite

The correct absolute time of a seismogram is an important prerequisite for many seismological processing methods. Recently, seismic interferometry has been applied to continuously estimate instrumental clock errors in certain regions. However, previous studies have focused on estimating clock errors in only one target region for each study, and data processing methods that provide more stable results in different regions have not been explored. This study presents a new method to estimate clock errors that are more stable in various regions based on seismic interferometry with windowed cross-correlation and least absolute deviation regression. The applicability of this method was validated by its application to 50 active volcanoes in Japan. We found clock errors at six stations at five volcanoes between January 2020 and June 2021. The maximum clock errors ranged between 0.2 and 7 s. This value range is significantly larger than the amplitude of the background fluctuation in the estimated values of clock errors, which is less than 0.05 s for most volcanoes. A comparison of different approaches for the estimation of clock error shows that our proposed method that uses windowed cross-correlation and least absolute deviation regression can reduce the effect of waveform changes in seismic ambient noise cross-correlation functions, probably because of noise source fluctuations. Managing the time stamps of data using the method proposed in this study will contribute to data quality assurance and ensure the reliability of analysis using time information in various study regions.

show abstract

Scattering and intrinsic absorption parameters of Rayleigh waves at 18 active volcanoes in Japan inferred using seismic interferometry

Cited by 3 publications

References 42 publications

Seismic Scattering Property Changes Correlate With Ground Deformation at Suwanosejima Volcano, Japan

Seismic Scattering Property Changes Correlate With Ground Deformation at Suwanosejima Volcano, Japan

Anisotropic seismic velocity variations in response to different orientations of tidal deformations

Continuous monitoring of instrumental clock errors at 50 volcanoes in Japan based on seismic interferometry

Contact Info

Product

Resources

About