Publication information

Geological Survey of Canada
Open File 8925

Mapping tectonic stress at subduction zones with earthquake focal mechanisms: application to Cascadia, Japan, Nankai, Mexico, and northern Chile

A.P. Plourde and J.F. Cassidy

© His Majesty the King in Right of Canada, as represented by the Minister of Natural Resources, 2022

Permanent link: https://doi.org/10.4095/330943

Publications in this series have not been edited; they are released as submitted by the author.

Recommended citation

Plourde, A.P. and Cassidy, J.F., 2022. Mapping tectonic stress at subduction zones with earthquake focal
      mechanisms: application to Cascadia, Japan, Nankai, Mexico, and northern Chile; Geological Survey of Canada, Open File 8925, 1 .zip file. https://doi.org/10.4095/330943

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Contents

This study presents 3D grids of tectonic stress tensors using existing focal mechanism catalogs from several subduction zones, including Cascadia, Japan, Nankai, Mexico, and northern Chile. We bin data into 50 x 50 x 10 km cells (north, east, vertical), with 50% overlap in all three directions. This resulted in 181380 stress inversions, with 90% of these in Japan (including Nankai). To the best of our knowledge, this is the first examination of stress changes with depth in several of these regions. We also divide the northern Japan focal mechanism catalog into those before and those >6 months after the 2011 Mw 9.1 Tohoku-Oki earthquake and produce detailed 3D maps of stress rotation.

Directory structure

of_8925_readme.rtf (this file)
of_8925.pdf (report)
TableS1_FullStressInversionResults.csv (Table of all stress inversion results from this study)
Figures\ (folder containing 166 figures of stress inversion results, generally named as REGION_DEPTH.pdf, but with the specifiers PRE, POST, FULL, or ROTATION for northern Japan).

Author contact information

A.P. Plourde (alexandre.plourde@nrcan-rncan.gc.ca)
Geological Survey of Canada 
1 Challenger Drive 
P.O. Box 1006 
Dartmouth, Nova Scotia  
B2Y 4A2

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