Texas Stadium, the now-demolished former home of the Dallas Cowboys in Irving. Irving was founded in 1903 by J.O. Otto Schulze and Otis Brown. It is believed that literary author Washington Irving was a favorite of Netta Barcus Brown, and consequently the name of the town site, Irving, was chosen.
Shale is a fine-grained sedimentary rock that forms from the compaction of silt and clay-size mineral particles that we commonly call mud. This composition places shale in a category of sedimentary rocks known as mudstones. Shale is distinguished from other mudstones because it is fissile and laminated.
Slate is the metamorphic rock formed from shale. A pile of mud can turn into shale (a fine-grained sedimentary rock) with relatively low pressure, about 3 mi (5 km) down into the earth. With more pressure and some heat, shale can transform into slate.