The deformation research laboratory at UNL runs a compression box for sand models. Models to date cover the amount, distribution and timing of layer parallel shortening in fold-thrust belts, the effect of pre-existing faults in a deforming area and the effect of multiple detachment levels in the deforming system. We have modeled the situation occurring in the Midcontinent over the Nemaha Tectonic Zone, NE, and the layer-parallel shortening across the Golden Fault Zone in CO. Ongoing projects aim to refine the layer-parallel shortening results and to investigate the influence of erosion and depositional processes on a developing thrust wedge.