Oh my goodness I am so sorry I meant to post this a while ago! But what first came to my mind when reading the stone unit was the Grand Canyon. My cousins actually took a trip to the Grand Canyon a little while ago before covid hit and they said it was surreal. I was really interested so I did some research and found out that the Grand Canyon was ten miles wide and one mile deep! Also I found it really fascinating to see all the fossils that have been found there. This includes the brachiopods, crinoids, bryozoans, ferns, burrows of animals, sponges, cephalopods, tracks, coral, and trilobites just to name a few. The layers of the rocks in the Grand Canyon include the precambrian basement rock, bright angel shale, redwall limestone, supai group, hermit shale, coconino sandstone, and the kaibab limestone. The precambrian basement rock was said to be formed 1.8 billion years ago which is the oldest rock there! The newest rock there is about 270 million years old which is the kaibab limestone, and that is the rock that people walk on. I have definitely added this place to my list of places I want to travel too! It is just so beautiful, below I included a few pictures that I have found online that capture its beauty!