That sinking feeling. A quick movie of a high-resolution 2D discrete element simulation, the average element radius is 0.75m. Here we have a 100 m thick, homogeneous, frictional-cohesive cover subject to a total of 30m block subsidence at its base. This simulation is part of a series where I have been looking at different strengths of such high-level covers. The simulation (like all) is subject to an initial "equilibration" phase, which is shown here for completeness. In the top half of the movie the simple geometric "collapse" is shown, whilst in the bottom half the incremental max. shear strain over the previous 1m subsidence is shown. High-resolution models like this are computationally quite intensive but worth the wait I think.
download movie below
