Problems and solutions in physical simulation of extensional structures

Key words:  extensional tectonics  materials  boundary conditions  force summing  sand box experiment

Abstract:

By designing various experimental models, filtrating the humidity and the particle size of the material, adjusting the dip of the boundary fault and the depth of the detachment surface, and changing the direction and size of the force exerted on the boundary, the impacts of various factors on the experimental results were compared, and the problems existing in every sectors were analyzed and solved. The results show that under the same boundary conditions, the generation of faults in the model is inhibited with the increase of the material humidity, and the faults on the plane are not easy to be preserved with the increase of the rolling particles proportion. Within the distance of L₀ from the boundary faults, the secondary faults are formed with the common effect of tension stress and gravity, nearly parallel with the boundary faults. Beyond the distance of L₀, the model deformation is mainly controlled by the tension stress, and the generated faults are perpendicular to the tension stress. Force conduction problems existing in the model with stretch and tilt can be solved with the well designed model.