Existing comment:
Conglomerates:
Conglomerates are what their name implies -- a collection of cobbles and pebbles cemented together. The sandstone caprock of Blue Mesa that you are walking through contains gravels that were carried in a stream and laid down here 225 million years ago. The different-sized pebbles in this conglomerate indicate that the stream was moving too fast to do a good job of sorting the rocks. |