pedestal rock (mushroom rock) An unstable, mushroom-shaped land-form found typically in arid and semi-arid regions. The undercut base was formerly attributed to wind abrasion, but is now believed to result from enhanced chemical weathering at a site where moisture would be retained longest. A famous example is Pedestal Rock, Utah, USA.

pedestal rock(mushroom rock) An unstable, mushroom-shaped land-form found typically in arid and semi-arid regions. The undercut base was formerly attributed to wind abrasion, but is now believed to result from enhanced chemical weathering at a site where moisture would be retained longest. A famous example is Pedestal Rock, Utah, USA.