Just got back from Moab myself. It was more a climbing trip than photography, but I got some good stuff anyway. Are those photos from Devil's Garden, or maybe the Furnace?
I love how dependent photos in Arches are on the weather. The right sky can make a good photo amazing. Last week was mostly bluebird skies for us; nice for climbing, though.
Getting low in the first shot c/w the sky is fantastic!
What time of day where these taking?