Love those ripples in the sand! Glad you turned around. The B&W really helps to emphasize the shadows.
One of the nice things about the Great Sand Dunes is that's it's so huge, there is a good mile or so of a main entry point and people generally get spread out really fast. As opposed to say Mesquite Dunes in Death Valley where everyone is starting out from one main entry point, and while they spread out a bit they tend to all follow the same paths. So in Mesquite you have to really work to find areas without footprints, or go out early in the morning after a strong wind.