Article
Geosciences, Multidisciplinary
C. Aiken, K. Obara
Summary: This study identified over 900 slow earthquakes in southwest Japan through data-driven clustering of tremor and low-frequency earthquake catalogs, establishing a more comprehensive database on slow earthquakes in the region. Small slow earthquake clusters exhibit similar scaling properties in terms of energy, duration, and rupture area to larger magnitude fast and slow earthquakes. While small slow earthquake clusters tend to rupture faster in their preferred direction, the average inter-event rupture speeds are comparable to those of larger slow earthquakes, suggesting that rupture speed may not necessarily control the spatial extent or eventual magnitude of slow earthquakes.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
R. Plata-Martinez, S. Ide, M. Shinohara, E. S. Garcia, N. Mizuno, L. A. Dominguez, T. Taira, Y. Yamashita, A. Toh, T. Yamada, J. Real, A. Husker, V. M. Cruz-Atienza, Y. Ito
Summary: New offshore observations in the Guerrero seismic gap discovered shallow slow earthquakes, which suggest that a portion of the plate interface undergoes stable slip. This may explain the long return period of large earthquakes and why have previous large earthquakes not propagated into the gap.
NATURE COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
Hui Huang, Jessica C. Hawthorne
Summary: This study investigates the scaling of tremor near Parkfield, California, and finds that tremor and slow slip events are governed by the same fault zone process.
NATURE COMMUNICATIONS
(2022)
Article
Geochemistry & Geophysics
Chao Song, Allan M. Rubin
Summary: Researchers investigated tremor signals by locating windows in different frequency bands, finding that during rapid tremor migrations, low-frequency energy appears to lag behind high-frequency energy by roughly 500 meters. This suggests that tremor may consist of more than just a collection of LFEs.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Review
Environmental Sciences
James D. Kirkpatrick, Ake Fagereng, David R. Shelly
Summary: The recognition of slow earthquakes has transformed the understanding of plate motion mechanisms, but the mechanics behind slow earthquakes remain enigmatic. Geoscientists have synthesized geological observations of ancient deformation structures to gain insights into fault slip mechanics.
NATURE REVIEWS EARTH & ENVIRONMENT
(2021)
Article
Geochemistry & Geophysics
C. G. Sammis, M. G. Bostock
Summary: The study analyzes a catalog of low frequency events beneath Vancouver Island in the context of a granular flow model. It finds that the LFEs do not follow Gutenberg-Richter statistics, but are normally distributed with respect to magnitude, and log-normally distributed with respect to moment. The model suggests that LFE families correspond to granular jams in flow that persist over multiple ETS episodes.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geosciences, Multidisciplinary
Randolph T. Williams, James D. Kirkpatrick
Summary: This study examines the variability in slip per inferred low-frequency earthquake (LFE) and tests different hypotheses regarding the controls on LFE moments. By analyzing the geometry of slickenfibers, the study finds characteristic slip increments and supports a slip-limited model with large variability in LFE rupture areas.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Multidisciplinary Sciences
Huihui Weng, Jean-Paul Ampuero
Summary: A new model elucidates the connections between silent earthquakes (slow slip events) and regular ones by accounting for their finite rupture depth. It reconciles debated features of slow slip events and explains how they might lead to earthquakes.
NATURE COMMUNICATIONS
(2022)
Article
Geochemistry & Geophysics
Yuta Mitsui, Keiji Uehara, Issei Kosugi, Koji Matsuo
Summary: This study investigates the occurrence of various earthquakes and slow slip phenomena in subduction zones. It is found that regions with high background seismicity correspond to the source areas of large slow slip events, which are not associated with tectonic tremors. Furthermore, these regions also coincide with areas of low free-air gravity anomalies. This suggests that widespread stress perturbations, possibly coupled with pore fluid effects, control seismic and aseismic slip on subduction faults.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Genki Oikawa, Naofumi Aso, Junichi Nakajima
Summary: The study focused on determining the focal mechanisms of 264 deep low-frequency earthquakes in 26 volcanic regions in Northeast Japan. It found that shallower seismic events are consistent with the regional stress field, while deeper events show varying focal mechanisms. The triggering of deep slow earthquakes is likely induced by stress changes caused by large earthquakes.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Multidisciplinary Sciences
Yuta Mitsui, Hinako Muramatsu, Yusaku Tanaka
Summary: Slow deformations associated with a subducting slab can affect quasi-static displacements and seismicity over a wide range of depths. Our study in the Tonga subduction zone found that transient displacements and quiescence of deep earthquakes were bounded in time by large intraslab earthquakes in 2009 and 2013. The slow deformation event between 2009 and 2013 may have been triggered by a distant and shallow M8.1 earthquake, providing new insights into the relationship between shallow and deep earthquakes in the subduction zone.
SCIENTIFIC REPORTS
(2021)
Article
Multidisciplinary Sciences
Satoshi Ide, Gregory C. Beroza
Summary: The scaling law for slow earthquakes, proposed 15 years ago, has been subject to debate on the differences between slow and fast earthquakes. New observations show that the linear scaling of slow earthquakes remains valid, but with an upper bound on moment rate of -1013 Nm/s. This suggests that the proposed scaling should be seen as a speed limit for slow earthquakes.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Geosciences, Multidisciplinary
Whitney M. Behr, Taras Gerya, Claudio Cannizzaro, Robert Blass
Summary: In this study, numerical models were used to explore the seismic slip characteristics of frictional-viscous megathrust shear zones, revealing the importance of stress heterogeneity in controlling earthquake propagation speed and slow slip transmission distance.
Article
Geosciences, Multidisciplinary
Caroline Mouchon, William B. B. Frank, Mathilde Radiguet, Piero Poli, Nathalie Cotte
Summary: Geodetic positioning is the reference for slow slip events, but daily solutions limit studies. Low-frequency earthquakes can provide a high-resolution time history of slow slip dynamics. The ratio of geodetic to seismic fault slip varies with time, suggesting the saturation of the earthquake source region as slow slip grows.
Article
Geosciences, Multidisciplinary
K. Chaudhuri, A. Ghosh
Summary: This study reveals the occurrence of slow earthquakes, including tremors and low-frequency earthquakes, in the south-central range of Taiwan. Using a grid-search moment tensor inversion algorithm, very low frequency earthquakes (VLFEs) have been detected and a robust VLFE catalog for 3 years has been created. The study shows that there is a significant increase in VLFE activities preceding earthquake swarms and a correlation between VLFEs and fast earthquakes.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Yuxiang Liu, Xueting Wei, Qi Liu, Xiaofei Chen
Summary: Extracting the dispersion energy image is a crucial step in surface wave analysis to obtain the vertical velocity structure. The quality of the dispersion energy image directly affects the accuracy of dispersion curves and subsequent inversion. The DSFK transform is introduced as a method to obtain theoretical 2-D dispersion energy images from multichannel data, bypassing the extraction step.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)