Why do they call it a “play”?  The real definition (from the OED, below) is revealing.

What with nuclear energy going down the tubes, there’s a big focus on gas. (That could be a good thing, because it brings into clear focus needs to understand what is going on with hydrofracking and its environmental consequences.) But why do so many refer to it as a “play,” or “natural gas play,” or “Marcellus play” and such. The moneyed interests in particular like to call it a “play, ” such as this one

The hottest natural gas play in North America is the Marcellus Shale.

The Oxford English Dictionary has it, way down the definitions list for the word “play” as a noun, at position 15b:

Oil Industry (orig. U.S.). An investment or development opportunity; a commercial venture the success of which depends upon speculation.

Speculation. Investors and environmentalists alike take note.