Changes

[[file:Grand_Staircase_6.jpg|thumb|500px|[http://written-in-stone-seen-through-my-lens.blogspot.com/2013_04_01_archive.html The Permian Red Beds of Dead Horse Point, Canyonlands, Utah]. Courtesy of Dr. Jack Share.]]

[[file:Grand_Staircase_6.jpg|thumb|500px|[http://written-in-stone-seen-through-my-lens.blogspot.com/2013_04_01_archive.html The Permian Red Beds of Dead Horse Point, Canyonlands, Utah]. Courtesy of Dr. Jack Share.]]

[[File:Permian sponge reef.jpg|thumbnail|500px|Permian sponge reef in Guadalupe Mountains, west Texas.The top of the cliff was bound during the Permian by sponges and other reef-building organisms; the flanks are the ancient slopes connecting the reef with the basinal depth]]

[[File:Permian sponge reef.jpg|thumbnail|500px|Permian sponge reef in Guadalupe Mountains, west Texas.The top of the cliff was bound during the Permian by sponges and other reef-building organisms; the flanks are the ancient slopes connecting the reef with the basinal depth. Source: Wikimedia Commons]]

==Useful links==

==Useful links==