"Oops," says the United States Geological Survey, "We used to think the shale on the East coast of the U.S., which gas companies are currently fracking into submission, had a metric buttload of natural gas. Turns out it only 0.2 metric buttloads." (I'm paraphrasing.)
Yesterday, the USGS's estimate of U.S. reserves of gas trapped in the Marcellus shale went from 410 trillion "technically recoverable" cubic feet of gas to 84 trillion in the span of a single report.
Because this week is Ragnarok and, basically, ghouls are in charge, the natural gas industry actually cheered this report, noting that it still represented significantly more reserves than the USGS estimated were in the shale in 2002. Back then, before fracking was widespread, it was estimated there were only 2 trillion cubic feet of technically recoverable gas in the Marcellus.
Also important: none of these estimates reflect how much of this gas can profitably be extracted from the ground. Because that mostly depends on how desperate we become and how hard we decide to ignore the down sides of fracking.