shale

And that may well be what is happening in the Barnett Shale region around, yes, Dallas and Irving.

Thanks to the shale revolution, domestic oil production is soaring.

Volcanoes spewed lava and ash, ocean floors were thrust upward, sand and rock and shale settled into slurry.

Thanks to the shale revolution and new technology, locomotives could burn a lot cleaner and cheaper.

Thanks to the shale revolution, the U.S. has abundant supplies of natural gas.

They learned that many of the mountains were extinct volcanoes and admired the brilliant colored sandstone and shale formations.

The mud afterwards hardens, and becomes a kind of rock known as shale.

"These roads are very dusty," he remarked, wiping a splinter of fine shale from his own eyes.

All three were natives of the soil, and somewhat sluggish in nature, like its sticky red shale.

It is a dead land, mere shale and rock and crumbling earth, devoid of the riches which alone would make it habitable.