I finally labelled the pictures for the Dewey Bridge and Cororna Arch trail. The Dewey Bridge is the namesake for the Dewey Bridge member of the Entrada formation. The Dewey Bridge formation is on top of the Navajo Sandstone. It erodes away quickly ... which is why you often come across large areas of exposed Navajo Sandstone.
The Corona Arch Trail is a fun short (3 mile round trip) walk near Moab. The trail crosses exposed sandstone and involves a few traverses and scrambling. It is a good place to test one's legs on the slickrock. Unfortunately, the group I was with was pressed for time and turned around before we got to the killer shots of Corona arch. I guess I will have to go back.