'The United States is banking on decades of abundant natural gas to power its economic resurgence. That may be wishful thinking.
...Companies are betting big on forecasts of cheap, plentiful natural gas. Over the next 20 years, US industry and electricity producers are expected to invest hundreds of billions of dollars in new plants that rely on natural gas. And billions more dollars are pouring into the construction of export facilities that will enable the United States to ship liquefied natural gas to Europe, Asia and South America.
All of those investments are based on the expectation that US gas production will climb for decades, in line with the official forecasts by the US Energy Information Administration (EIA). As agency director Adam Sieminski put it last year: “For natural gas, the EIA has no doubt at all that production can continue to grow all the way out to 2040.”
But a careful examination of the assumptions behind such bullish forecasts suggests that they may be overly optimistic, in part because the government's predictions rely on coarse-grained studies of major shale formations, or plays. Now, researchers are analysing those formations in much greater detail and are issuing more-conservative forecasts. They calculate that such formations have relatively small 'sweet spots' where it will be profitable to extract gas.'
Natural gas: The fracking fallacy : Nature News & Comment
Though the above is not proof, it is more evidence.
I have said many times, and have posted links to other articles of evidence, that the shale/fracking frenzy is probably overblown.
There is (IMO) less recoverable oil/gas down there then is generally reported and the wells do not last nearly as long as conventional ones seem to.