Okay, guys and gals, this is my stupid question of the day. The other day VintageDirt and I were out for a desert ride and when we stopped to rest ( hush young people), we began to wonder what exactly were the forces that formed the three foot deep whoops we were just being slammed by. I mean I guess that I understand the basics, but why do they get deeper if we mostly ride the tops? :| This is actually a real question, VD and I put our considerable brains together and couldn't come up with anything that sounded convincing, so I am calling on the resources of my favorite bit of cyberspace to help me out here. Anyone?