1 Although nobody told Mr. Callahan until it was too late, the dark-hued shale rocks found in pockets along the Western Slope were oil shale. Often referred to as the rock that burns, oil shale boasts ...

Shale is a sedimentary rock made up of tiny grains of silica, clay and other minerals. Many types of rock have few physical ...

or simply the Marcellus Shale) is a unit of marine sedimentary rock found in eastern North America. Named for a distinctive outcrop near the village of Marcellus, New York in the United States ...