USGS - science for a changing world

Pacific Coastal and Marine Science Center

Tsunamis and Earthquakes

Animation of Tsunami Generated by Oblique Slip

USGS PCMSC Tsunami and Earthquake Studies


Link to metadata

Tsunami waves generated by oblique faulting are shown at 2 minute intervals after the initiation of the earthquake. Peaks in the tsunami waves are shown by red intensity, whereas troughs are shown by blue intensity. For a tsunami generated by pure thrust faulting, only the primary wavefronts would be evident: one moving toward the deep ocean and one moving toward the local shoreline. As shown here, fault movement parallel to the convergence direction between the Juan de Fuca and North American plates results in the generation of secondary wavefronts. Most obvious is the isolated secondary wavefront propagating to the southeast. In addition, there is a secondary wavefront propagating to the northeast that is a continuation of the shoreward primary wavefront. Both of the secondary wavefronts initially travel parallel to shoreline, but their paths of travel curve (refract) toward shore. Thus, the length of shoreline inundation from this type of tsunami is significantly greater than inundation from the primary wavefronts.

The parameters used to create this image are merely for illustrating the effect of oblique rupture on tsunami propagation. Certainly, variations in the chosen parameters would affect the amplitude of the tsunami and the physical location of coastal inundation.

Note: These QuickTime* movies are very large and may take a few minutes to download. Movies are a non-standard part of the internet and may not load for all viewers. If you do not have QuickTime please download the QuickTime Player here.

*Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Please note that some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented prior to final review and approval by the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user.


Accessibility FOIA Privacy Policies and Notices logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Laura Zink Torresan
Page Last Modified: 22 October 2008 (lzt)