These movies show a vertical dip-slip fault with one block displaced up. You can change these blocks in a way that you haven't done before - you can erode the uplifted block down to the same level as the other block. You are not moving the block in these movies, just eroding off the top. This will let you see what the surface looks like after faulting and erosion.
Even though the fault movement was vertical, which way does the blue layer appear to be offset on the top surface?
Rotate block 
Erode block
Rotate block
Erode block
