September 30, 2016
Sometimes you have to build the field in the laboratory. At the Virginia Tech Active Tectonics and Geomorphology Lab they do just that. This is the first in a series of posts shared from their The Geo Model blog.
By Phil Prince
In this model we show how different subsequent types of faults form in relationship to a strike-slip fault like the San Andreas fault.
Glass beads (used for sandblasting) create weak plane where the rock layers move past each other – also called a decollement horizons. These decollements activate due to the high friction at the base of the model provided by a sheet of 150 grit sandpaper. Slip or movement in the decollements forms high-displacement, nearly flat thrusts, which fold due to subsequent footwall deformation resulting from erosion of the wedge.
This model is patterned after the work of Jacques Malavieille and colleagues at Géosciences Montpellier, Université of Montpellier II.
This post was originally posted on 26 April 2016 at The Geo Models blog.