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  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

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Given the strong economic control of petroleum type on development of an [[accumulation]], the conversion of oil to gas or dilution of gas by nonhydrocarbon components in the deep burial environment may make an accumulation uneconomic and, from an exploration point of view, “destroyed.” The following burial processes destroy accumulations by altering the properties of the petroleum:

Given the strong economic control of petroleum type on development of an [[accumulation]], the conversion of [[oil]] to [[Natural gas|gas]] or dilution of gas by nonhydrocarbon components in the deep burial environment may make an accumulation uneconomic and, from an exploration point of view, “destroyed.” The following burial processes destroy accumulations by altering the properties of the petroleum:

* Gasification

* Gasification

Hydrogen sulfide concentration increases with depth in gas reservoirs with anhydrite, indicating that it, too, is a product of higher maturity.<ref name=ch11r20 /> The methane is reacting with the sulfate to form hydrogen sulfide and carbon dioxide gas. The reaction is probably kinetically controlled.

Hydrogen sulfide concentration increases with depth in gas reservoirs with anhydrite, indicating that it, too, is a product of higher maturity.<ref name=ch11r20 /> The methane is reacting with the sulfate to form hydrogen sulfide and carbon dioxide gas. The reaction is probably kinetically controlled.

The origin of nitrogen gas is not well characterized. In nonpetroleum basins, nitrogen may have high concentration because no other gas is present to dilute it. High-nitrogen gas in thermally mature basins is possibly from coal sources<ref name=ch11r33>Stahl, W., Boigk, H., Wollanke, G., 1978, Carbon and nitrogen isotope data of upper Carboniferous and Rotliegend natural gases from north Germany and their relationship to the maturity of the organic source material: Advances in Organic Geochemistry 1976, p. 539–559.</ref> or from the mantle or deep crust.<ref name=ch11r17>Jenden, P., D., Kaplan, I., R., 1989, [http://archives.datapages.com/data/bulletns/1988-89/data/pg/0073/0004/0400/0431.htm Origin of natural gas in Sacramento basin, California]: AAPG Bulletin, vol. 73, p. 431–453.</ref>

The origin of nitrogen gas is not well characterized. In nonpetroleum basins, nitrogen may have high concentration because no other gas is present to dilute it. High-nitrogen gas in thermally mature basins is possibly from [[coal]] sources<ref name=ch11r33>Stahl, W., Boigk, H., Wollanke, G., 1978, Carbon and nitrogen isotope data of upper Carboniferous and Rotliegend natural gases from north Germany and their relationship to the maturity of the organic source material: Advances in Organic Geochemistry 1976, p. 539–559.</ref> or from the mantle or deep crust.<ref name=ch11r17>Jenden, P., D., Kaplan, I., R., 1989, [http://archives.datapages.com/data/bulletns/1988-89/data/pg/0073/0004/0400/0431.htm Origin of natural gas in Sacramento basin, California]: AAPG Bulletin, vol. 73, p. 431–453.</ref>

==Predicting burial destruction==

==Predicting burial destruction==