"...The prize that drew companies such as PetroHawk to Smith's impoverished corner of Louisiana is known as shale gas. Smith's acres sit on top of the Haynesville Shale, named after the town near which the prospect was discovered - a seam of black rock between 150 and 300ft thick that lies hundreds of feet underground and extends across 3,400 square miles of Louisiana and Texas. Trapped inside this rock are vast quantities of natural gas - estimated at between 112 and 245 trillion cu ft. At the upper end of this range, Haynesville gas could meet the US's energy needs for about 12 years.
This isn't the most extensive prospect of its kind in the US; that distinction belongs to the Marcellus Shale in Pennsylvania and neighbouring states, which is reckoned to cover 65,000 square miles, an area larger than Greece. But based on the wells drilled so far, the Haynesville may well turn out to be one of the most productive..."
