|Pinnacle on North Rim (click on pic for larger version)|
You don't have to be a geologist to appreciate what's going on here. This landscape is constantly being worn down by erosion. Rocks falling apart, soil being built up and moved downslope. Vegetation, such as the green pinyon and juniper trees gracing the red slope with their dark green accents, adapting and growing.
Photographically, the distant canyon wall in afternoon shadow makes for a splendid dark blue background.
You might also be interested in my Grand Canyon Photography blog.