Claybox Models of Fault System Evolution

The rig

The experimental rig has two perpendicular (x-y) computer-controlled motors that provide unlimited movement of the right side of the deformation box.

Development of Normal Faults

For extensional experiments, a rubber sheet is glued to the base of the two metal sheets to provide a zone of uniform extensional strain.

Time 1

Normal faults form over the stretching rubber from small air bubbles

Time 2

These faults grow in length and develop relay structures

Time 3

Low-angle light revelas fault scarps as shadows

Time 4

In addition to large faults above the rubber sheeting, faults have formed over the metal plates.


Simulation of the Southern San Andreas

The development of the San Gorgonio knot can be investigated with analog models using both clay and sand.


Setup of basal plates to simulate the southern San Andreas

A compressional left-over is introduced in the material overlying the plates


laser scan of the defrmed clay surface


laser scan of the deformed sand layer