Spatiotemporal Variations in Slow Earthquakes Along the Mexican Subduction Zone

• Published in: Journal of geophysical research. Solid earth Vol. 123; no. 2; pp. 1559 - 1575
• Main Authors: Maury, J., Ide, S., Cruz‐Atienza, V. M., Kostoglodov, V.
• Format: Journal Article
• Language: English
• Published: Washington Blackwell Publishing Ltd 01-02-2018; American Geophysical Union
• Subjects: Accretion disks; Deformation; Deformation mechanisms; Detection; Earthquakes; Environmental Sciences; Geophysics; Mexican subduction zone; Profiles; scaled energy; Sciences of the Universe; Segmentation; Seismic activity; Shear stress; slow earthquakes; Subduction; Subduction zones; Temperature profile; Temperature profiles; Tidal energy; Tidal power; tidal sensitivity; tremor; Variation
• ISSN: 2169-9313; 2169-9356
• DOI: 10.1002/2017JB014690

Slow earthquakes in Mexico have been investigated independently in different areas. Here we review differences in tremor behavior and slow slip events along the entire subduction zone to improve our understanding of its segmentation. Some similarities are observed between the Guerrero and Oaxaca areas. By combining our improved tremor detection capabilities with previous results, we suggest that there is no gap in tremor between Guerrero and Oaxaca. However, some differences between Michoacan and Guerrero are seen (e.g., SSE magnitude, tremor zone width, and tremor rate), suggesting that these two areas behave differently. Tremor initiation shows clear tidal sensitivity along the entire subduction zone. Tremor in Guerrero is sensitive to small tidal normal stress as well as shear stress, suggesting that the subduction plane may include local variations in dip. Estimation of the energy rate shows similar values along the subduction zone interface. The scaled tremor energy estimates are similar to those calculated in Nankai and Cascadia, suggesting a common mechanism. Along‐strike differences in slow deformation may be related to variations in the subduction interface that yield different geometrical and temperature profiles.
Key Points
Along‐strike variations in slow earthquakes are observed in the Mexican subduction zone
Tremor is sensitive not only to tidal shear stress but also to tidal normal stress
Scaled tremor energy is similar to values reported for Japan and Cascadia