The promise of fracking in California's large Monterey Shale deposits was intoxicating: 13.7 billion barrels of oil, as estimated by the U.S. Energy Information Administration, were recoverable with existing technology, enough to bring 2.8 million new jobs to the state and boost tax revenue by $24.6 billion per year.

But the independent firm hired to evaluate the shale back in 2011 made the very incorrect assumption that the Monterey deposits would be as easy to tap as those in North Dakota and Texas -- and that turns out not to be the case. A new, revised estimate slashes that promise by 96 percent, putting the amount of recoverable oil at only 600 million barrels.

Advertisement:

The L.A. Times, which first reported the news, calls it "a blow to the nation's oil future" -- the Monterey Shale contains about two-thirds of the nation's shale oil reserves:

The new analysis from the Energy Information Administration was based, in part, on a review of the output from wells where the new techniques were used. "From the information we've been able to gather, we've not seen evidence that oil extraction in this area is very productive using techniques like fracking," said John Staub, a petroleum exploration and production analyst who led the energy agency's research. "Our oil production estimates combined with a dearth of knowledge about geological differences among the oil fields led to erroneous predictions and estimates," Staub said. Compared with oil production from the Bakken Shale in North Dakota and the Eagle Ford Shale in Texas, "the Monterey formation is stagnant," Staub said. He added that the potential for recovering the oil could rise if new technology is developed.

Oil industry officials are holding on to that promise, maintaing that since the oil is there, they'll eventually find a way to get to it. But environmentalists, for the time being, are declaring this the end of California's petroleum rush: