Loess
Late Pleistocene, younger than 126,000 years. 1 crag on this site has its map point on it.
What the map says
Silt with lesser amounts of clay and sand deposited by wind, generally downwind from areas of windblown sand.
1:100,000 sheet: Trimble and others, 2003, U.S. Geological Survey Geologic Investigations Series I-856-H (1 crag). A contact line at that scale is about 100 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.