A Treasury Department study last April found that the cutoff in Iranian oil exports "has not produced any shortage of crude" oil in the country.
The Treasury analysis, which is at odds with public statements by President Carter and former Energy Secretary James R. Schlesinger, was widely circulated among government agencies last spring.
Following critical comments from other agencies, including the Central Intelligence Agency, Office of Management and Budget, and the Energy Department, the detailed Treasury study was curtailed.
A copy of the Treasury report, "The Implications of the Iranian Crisis for the World Petroleum Situation," was obtained by the Washington Post under the Freedeom of Information Act.
The study said that "we have seen no evidence that accounts for the massive runup in refined oil products prices during the first quarter of the year, based on increases in crude oil prices during the same period.
Since December of last year, prices for petroleum products such as gasoline have risen by as much as 60 percent on world markets.
The report said, "A developing U.S. shortage in refined petroleum fuels, particularly unleaded gasolines, was not caused by Iran's crisis."
Rep. Benjamin Rosenthal, chairman of the House Commerce subcommittee on consumer and monetary affairs, has called on Treasury Secretary G. William Miller to find out "why the report has been suppressed and not made available to enforcement agencies, the Congress, and the public," according to a spokesman.
A letter from Treasury to The Post stressed that the 34 page report was a "draft" and at this point represented the view of the authors, Jay G. Polach and Cathryn Goddard, and not the Treasury.
The study argues that, as Iran's more than 5 million barrels of oil a day in exports were replaced by increased production from Africa, the North Sea and other producers, "the quality of available crude supply improved (rather than worsened) in terms of gasoline and mid-distillage yields." In effect, the study said, the output of refined products was enhanced.
The Treasury researchers argue that "as the quality of crude export streams has improved on the international market, a simple and mechanistic quantification -- on a barrel per barrel basis -- of the impact of the shortfall in Iran's crude exports is obviously misleading."
But at the time, Schlesinger and Carter repeatedly told Congress that as a result of the Iranian shortfall the U.S. was experiencing a nearly 800,000 barrel a day shortage, and the resulting shortage worldwide was from 1.6 to 2 million barrels a day.
Since the Treasury report was curtailed, the CIA and authoritative oil industry sources have said world oil production during the first half of 1979, despite Iran, was at record free-world levels, 5.8 percent higher than last year.
Officials in other cabinet agencies familiar with the study, who asked not to be identified, said it is not inconsistent with the administration's findings in many areas, and the Treasury analysis was reviewed as innovative.
The study recommended that "before a model of generalized and acute scarcity in petroleum supplies is adopted as a premise for U.S. international oil policy, more data should be sought from all parties."
In April, the study said, "available data do not support the claim that diminishing crude reserves are the basis of increasing" oil costs. Free world oil reserves were about 590 billion barrels in 1975, and now are listed in unclassified CIA reports as 592 billion, the study said.