How does one know
that this is indicative of an ancient desert setting?
What you see here up-close is called cross-bedding,
and it shows consecutive layers of wind-blown sand, cutting each
other off as ancient winds shifted in direction, in a scene not unlike
today's
Sahara Desert.
This type of sandstone is described as "eolian" or "aeolian" by geologists,
and the image here shows a section about 3 feet (1 meter) in height.
