Ronald Blakey, illustrator of Ancient Landscapes of the Colorado Plateau, creates some interesting visualizations:

I actually forget when I first started with Photoshop — probably in the mid-1990s. When I found that, I just thought, wow: the power of this is incredible. I quickly learned how to use the cloning tool, so that I could clone modern topography onto ancient maps, and that made things even simpler yet.

Check out the whole piece on The Atlantic.