The Localization of Sandstone Deposits

The Green River Formation in Wyoming is a series of deposits that are confined to particular basins. So you're talking about something much more localized. An example might be the topic sandstone that we find in Grand Canyon and in the base of Grand Canyon. That's part of an enormous blanket of sand, called the Sork sandstone,. And there are similar sandstones at similar levels in the geological column across Europe and Africa and the Middle East and parts of South America.