If you were to look closely at the rocks in the cliffs of Zion Canyon,
you would observe rocks composed largely of sandstone called the Navajo
Sandstone. The sand grains in the Navajo Sandstone are very well sorted
and highly rounded. The sand is composed almost completely of quartz and
therefore classified as a quartz sandstone.
The Navajo Sandstone is referred to as a formation, which is a
unit of rocks that can be mapped for a long time. There are other rock
formations throughout the park that indicate changing environments
through time, as shown in the diagram. The Navajo Sandstone occurs in
distinct beds. A bed is a layer of sediment or sedimentary rock.
Most beds form as sediment is deposited