Tectonic low-frequency earthquakes in Shikoku, Japan: source scaling, size distribution and observational limits

Supino, Mariano; Shapiro, N. M.; Vilotte, Jean‐Pierre; Poiata, Natalia; Obara, Kazushige

doi:10.1002/essoar.10506594.1

Cited by 4 publications

(13 citation statements)

References 101 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Consequently, a comprehensive magnitude-completeness analysis based on self-similarity and G-R statistics may not be appropriate in the treatment of LFEs. Rather, we will consider the issue of magnitude completeness within the context of results from recent studies seeking to define LFE scaling relations in Mexico (Farge et al, 2020) and in Japan (Supino et al, 2020(Supino et al, , 2021. The former study applied a network-template methodology similar to that of Bostock et al (2015) to LFEs from the Guerrero subduction zone and arrived at similar conclusions concerning moment-duration scaling, namely that LFE duration is only weakly dependent upon moment (T ∝ M 0 1/10 ).…”

Section: Magnitude Completeness and Scalingmentioning

confidence: 97%

“…For example, Supino et al. (2021) chose to avoid analyzing data over periods of months following large ( M w > 6), local earthquakes due to contaminating effects of aftershocks. Accordingly, and by G‐R scaling, frequent and small regular earthquakes are also likely to be present at some level within their catalog.…”

Section: Characteristics Of Lfes and Lfe Families In The Cascadia Subduction Zonementioning

confidence: 99%

“…The former study applied a network-template methodology similar to that of Bostock et al (2015) to LFEs from the Guerrero subduction zone and arrived at similar conclusions concerning moment-duration scaling, namely that LFE duration is only weakly dependent upon moment (T ∝ M 0 1/10 ). The studies by Supino et al (2020Supino et al ( , 2021 employed a different approach to assemble an LFE catalog for Shikoku, and suggest that LFE moment-duration scaling there is similar to that of regular earthquakes (T ∝ M 0 1/3 ). Interestingly, the magnitude-frequency distribution of their catalog closely resembles a normal distribution with mean and standard deviation that are very similar to those shown in Figure 4.…”

Section: Magnitude Completeness and Scalingmentioning

confidence: 99%

“…However, such approaches may suffer from the problem of admitting signals that are not of SAMMIS AND BOSTOCK 10.1029/2021JB021963 5 of 17 interest. For example, Supino et al (2021) chose to avoid analyzing data over periods of months following large (M w > 6), local earthquakes due to contaminating effects of aftershocks. Accordingly, and by G-R scaling, frequent and small regular earthquakes are also likely to be present at some level within their catalog.…”

Section: Magnitude Completeness and Scalingmentioning

confidence: 99%

“…Supino et al. (2021) concluded that their catalog is incomplete at large magnitudes due to secondary microseismic noise and at small magnitudes due to network‐dependent detection thresholds, thus preventing them from discriminating between the G‐R size distribution and any deviation from it. The authors did not comment upon the symmetry of their distribution which, in light of the observations reported in the current study, warrants scrutiny.…”

Section: Characteristics Of Lfes and Lfe Families In The Cascadia Sub...mentioning

confidence: 99%

See 4 more Smart Citations

A Granular Jamming Model for Low‐Frequency Earthquakes

Sammis

Bostock

2021

JGR Solid Earth

View full text Add to dashboard Cite

show abstract

Section: Magnitude Completeness and Scalingmentioning

confidence: 97%

Section: Characteristics Of Lfes and Lfe Families In The Cascadia Subduction Zonementioning

confidence: 99%

Section: Magnitude Completeness and Scalingmentioning

confidence: 99%

Section: Magnitude Completeness and Scalingmentioning

confidence: 99%

Section: Characteristics Of Lfes and Lfe Families In The Cascadia Sub...mentioning

confidence: 99%

See 3 more Smart Citations

A Granular Jamming Model for Low‐Frequency Earthquakes

Sammis

Bostock

2021

JGR Solid Earth

View full text Add to dashboard Cite

show abstract

Cataloging Tectonic Tremor Energy Radiation in the Cascadia Subduction Zone

Wech

2021

JGR Solid Earth

View full text Add to dashboard Cite

Aseismic processes are increasingly recognized as a fundamental part of plate boundary dynamics and the earthquake cycle. These processes generate a broad range of geodetic and seismic signals, including tectonic tremor (Obara, 2002), which has been observed in numerous subduction zones worldwide (e.g., Ide, 2012). These persistent, low-frequency seismic signals can last days to weeks, coinciding with slow slip at the megathrust plate boundary (Rogers & Dragert, 2003), but they also occur in shorter bursts that likely reflect slip occurring below geodetic resolution (e.g., Wech et al., 2010). These events represent valuable scientific targets for improving our understanding of fault conditions, slip processes and earthquake rupture dynamics, and are a focus of seismic and geodetic monitoring to track potential long-term and time-dependent hazards associated with their occurrence. Documenting when, where and how much tremor occurs provides a basis for investigating tremor and slip behavior. Many studies have documented and characterized spatiotemporal patterns of tectonic tremor activity, including how it relates to geodetically observed slow slip events (SSEs) (e.g., Bartlow et al., 2011;

show abstract

Segmentation characteristics of deep, low-frequency tremors in Shikoku, Japan using machine learning approaches

Chen

Chiu

Obara

et al. 2023

Earth Planets Space

Self Cite

View full text Add to dashboard Cite

Shikoku island, southwestern Japan lies in the western Nankai Trough and showcases along-strike segmentation of slow earthquake behavior. Whether the spatial variation of tremor behavior reflects the regional differences in structure/source properties and how much such differences can be recognized by the seismic signals themselves are two questions addressed in this paper. Taking advantage of advanced methods in recognizing and classifying signals using machine learning approaches, we attempt to answer them by conducting signal classification experiments in Shikoku. Based on the tremor catalog from 1 June 2014 to 31 March 2015, the tremors recorded in four different areas were treated as different classes and segmented into 60-s-long signals. The number of tremors in four different areas (A to D, from west to east) reached 15,000, 31,000, 10,000, and 16,000, respectively. To efficiently distinguish between tremors from different areas, we applied a k-nearest neighbor (k-NN) classifier with Fisher’s class separability criteria to select the optimal feature subset. The resulting classification performance reached more than 90% at all 12 stations. We further designed a triangle test to select the features that can better represent the differences in source properties between areas. We found that the most efficient features were associated with (1) the number of peaks in the temporal evolution of discrete Fourier transforms and (2) the energy distribution in the autocorrelation function (ACF). To match the difference in behavior revealed by the ACF, the size of the tremor zone, which mainly controls how long the seismic energy lasts in a tremor episode, was determined to be largest in Area B and smallest in Area C. The heterogeneity of the asperities in a tremor zone, which may control how spiky the tremor signals developed over time, was determined to be strong in Areas B and C. Together with previously documented variations in slow earthquake behavior in the same area, we finally propose a conceptual model that provides a better understanding of the regional differences in the tremor source properties in Shikoku, Japan. Graphical Abstract

show abstract

Tectonic low-frequency earthquakes in Shikoku, Japan: source scaling, size distribution and observational limits

Cited by 4 publications

References 101 publications

A Granular Jamming Model for Low‐Frequency Earthquakes

A Granular Jamming Model for Low‐Frequency Earthquakes

Cataloging Tectonic Tremor Energy Radiation in the Cascadia Subduction Zone

Segmentation characteristics of deep, low-frequency tremors in Shikoku, Japan using machine learning approaches

Contact Info

Product

Resources

About