Tectonics and seismicity of the southern Washington Cascade range

W. D. Stanley; S. Y. Johnson; A.I. Qamar; C.S. Weaver; J. M. Williams

doi:10.1785/bssa08601a0001

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Tectonics and seismicity of the southern Washington Cascade range

W. D. Stanley·S. Y. Johnson·A.I. Qamar·C.S. Weaver·J. M. Williams

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Abstract

Geophysical, geological, and seismicity data are combined to develop a transpressional strain model for the southern Washington Cascades region. We use this model to explain oblique fold and fault systems, transverse faults, and a linear seismic zone just west of Mt. Rainier known as the western Rainier zone. We also attempt to explain a concentration of earthquakes that connects the northwest-trending Mount St. Helens seismic zone to the north-trending western Rainier zone. Our tectonic model illustrates the pervasive effects of accretionary processes, combined with subsequent transpressive forces generated by oblique subduction, on Eocene to present crustal processes, such as seismicity and volcanism.

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Bulletin of the Seismological Society of America Article

Source-reported bounding extent: 45.491923818603595° to 47.04113301131156° latitude; -123.06312586247054° to -120.51429773747068° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

W. D. Stanley, S. Y. Johnson, A.I. Qamar, C.S. Weaver, J. M. Williams. 1996-02-01. Tectonics and seismicity of the southern Washington Cascade range. https://doi.org/10.1785/bssa08601a0001

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