Morrison, Ralston Creek, and Entrada (or Exeter) Fms
Jurassic, about 164 to 145 million years old. 3 crags on this site have their map point on it.
The map groups these named formations into this unit: Morrison Formation, Ralston Creek Formation, Entrada Sandstone.
What the map says
The sheet gives no description for this unit. Lithology: sandstone, mudstone, claystone.
1:500,000 sheet: Horton and others, 2017, U.S. Geological Survey Data Series 1052 (3 crags). A contact line at that scale is about 500 m wide on the ground.
Served by Macrostrat (CC BY 4.0). The wording is the map's own, quoted as a fact about the mapped unit, not about any one wall.