Shale gas is a natural gas extracted from shale rocks and coal seams.
The island has an area of 1.16 km2 and consists of shale rock.
The mountain is made up mostly of shale rock, which can easily slide onto the road surface throughout the year.
The development of new techniques for fracturing shale rocks to release their load of natural gas has revolutionised the energy industry in the past three years.
The township is not named for the numerous deposits of shale rock found within its borders; this is instead a common misconception.
Extracting natural gas from shale rock is rapidly spreading to countries outside the United States.
Shale gas is a by-product of shale rock.
The surface consists mostly of broken shale rock.
There was Bowly, ambling around the big shale rock that marked their camp.
Fracking involves drilling into hard shale rocks to shatter them and release the natural gas inside.