One of my former graduate students (Paul Jensen) and one of my current graduate students (Skyler May) have worked on these Late Triassic Rocks along the south flank of the Uinta Mountains. They are interesting rocks with interesting sedimentary structures. We traveled out there this week to look at them again.
Red Fleet along the south flank of the Uintas. The particular rocks we are studying are the rocks that make up the "deck" of the ship and the red cliff above the lower slope. The lower slope is the Chinle Formation, the red cliff and deck of the ship are the Bell Springs Formation, and the upper lighter red rocks forming the top part of the ship are the Nugget Sandstone.
Dinosaur National Monument to the east of the Red Fleet section and the big cliff forming sandstone that was characteristic of the formation at Red Fleet is absent. Photo taken in 2012.
paleogeographic map of the Bell Springs Formation time period. According to his map, northeastern Utah would have been part of a broad fluvial plain stretching out to the west from the highland areas of Colorado to the ocean and island arc along the western margin of North America.