Hole in the Cliff
These small, human formed caves are called caveates (cave-ate) by archaeologists. The caveate is excavated in silvery gray volcanic ash made up of two distinct beds of ash and was deposited by a nearby volcano eruption 6.8 million years ago.
The lower bed is slightly more resistant to erosion and was left to form a bench inside the cave. This bed represents the accumulation of ash that fell out of the sky from a high plume of ash and vapor.
The thicker upper bed, with diffuse layers, is the deposit of a dune of ash that was blown around by the win. This bed is very soft and was easily excavated to make the cave with the ash-fall bed forming the bench inside the caveate.