A mushroom rock may ultimately form from an originally flat area of hard rock overlying soft rock, similar to the pattern of rocks that form a waterfall. Weathering of the exposed hard rock layer eventually exposes the lower rock to erosion from wind, water, salt intrusion, etc., depending on local conditions. The layer of softer rock is more readily eroded, leading to the formation of a depression or blowout. The overlying harder rocks are resistant to this process, and may ultimately end up as isolated mushroom rocks standing above the new, lower plain.