Accurate estimates are important for lawmakers who are making long-term decisions about subsidies and policies relating to the nation’s energy mix. They are also essential for landowners and investors as they decide where and whether to lease their land to drillers or invest in gas companies. Some market analysts say that the large differences between public estimates for natural gas resources provide further evidence that there may be more risk and uncertainty involved with gas drilling than many investors realize. Amid growing questions about the administration’s research, Howard K. Gruenspecht, the agency’s acting director, appeared before Congress in July to reiterate that, despite some uncertainties, his agency’s estimates were accurate.

But on Tuesday, the administration said it would sharply downgrade those estimates. “We consider the U.S.G.S. to be the experts in this matter,” said Philip Budzik, an operations research analyst with the Energy Information Administration, according to Bloomberg, which was the first to report the decision by federal officials to downgrade their estimates. “They’re geologists; we’re not. We’re going to be taking this number and using it in our model.”

A spokesman for the administration added that while the new estimates were very important, drilling costs and well performance may have a larger impact on future natural gas production.

The new federal numbers are also much lower than the roughly 350 trillion cubic feet estimated to be technically recoverable in the Atlantic region, home to the Marcellus Shale, by the Potential Gas Committee, a nonprofit group of industry experts and academics, in an April report. Still, industry association officials cheered the new report.

Kathryn Z. Klaber, president of the Marcellus Shale Coalition, described them as “further affirmation that the Marcellus Shale will continue to safely produce prolific amounts of clean-burning American natural gas for generations to come.” The new estimates are much higher than the last assessment by the Geological Survey in 2002. Those estimates — which suggested the Marcellus contained only about two trillion feet of recoverable gas — were provided before new technology had drastically increased drilling for natural gas in shale formations.