Making Foot Prints on the sand in animations.

Hi ! I was wondering for a moment about the best way of making foot prints on the sand in animations, and I finally found some time to make some experiments.
As I have been a long time without adding tutorials on my site, I have thought that I could share the result ofmy trials with the community.
I hope that you will find this usefull :
http://3d-synthesis.com/Displacement_Tutorial.html
Still and animated textures are downloadable, and you will find the demo movies at the end of the page.
Philippe.