February 7, 2017

When Strike-Slip Faults Bend

Posted by larryohanlon

Sometimes you have to build the field in the laboratory (or in this post’s case, in the art museum). At the Virginia Tech Active Tectonics and Geomorphology Lab they do just that. This is the latest in a series of posts shared from their blog. More of their posts can be found here.

Text by L. Whalen

Models by P. Prince

Strike-slip faults often seem like the least complex faults out of the bunch compared to thrust and normal faults, but it turns out that there’s a lot more to be said (and modeled)!

Strike-slip faults are where the crust is sliding past one another and can form linkages between areas experience convergence or divergence. Where strike-slip faults bend things get interesting as it creates zones of compression (called restraining bends) and tension (called releasing bends).

This video shows the development of a restraining and a releasing bend and then shows a cross-section of the model highlighting the different flower structures (for more information on flower structures see our previous post).

A real world example of where you can find  these structures is the fault system responsible for the Mw 7 earthquake that affected Haiti on January 12th, 2012.

Zoomed out map of Haiti. For explanation of butterfly outcrop patterns see the video above.

Zoomed in map of Haiti. Note the butterfly pattern in pink.

A) Elevation map of Haiti. B) cross-section showing flower structure located on line A-A’. C) 3-D block diagram showing another view of the structure. Figure from Saint Fleur et al. (2015).


This post was originally posted on The Geo Models blog.