Four miles into the park we come to Nizhoni Point. In Navajo Nizhoni means pretty or beautiful. Here you will find the site of a 200 million year unconformity. This is a gap in the geologic record. The Bidahochi formation that caps the cliffs was deposited between 4 and 8 million years ago. The Bidahochi consists of brown mudstone and black basalt that flowed from a volcano that erupted here. The pink mudstone below belongs to the Chinle formation that was deposited some 225 million years ago. The question is where did 200 million years of geologic history between the Chinle and Bidahochi formations go?
