Are you staying in Flagstaff and headed to the Grand Canyon's South Rim? If so, this field trip guide may interest you and provide you with a more enjoyable and educational journey!
Ten years ago in 2014, I served as a co-leader on a field trip sponsored by the Association of Engineering Geologists and the Arizona Geological Survey. As part of the field trip, I helped write a mile-by mile road log of the geology of the route that covers 110 miles. You can access the field trip guide here. You may need to be a subscriber to academia.edu to access the field trip guide. Enjoy the trip!