Biodegradation of aromatic hydrocarbons in crude oils from the Barrow Sub-basin of Western Australia

The distributions of methylated naphthalenes in crude oils carry within them detailed information regarding the geological history of the oils. The effects of thermal stress, mixing, biodegradation and migration contamination all leave recognisable imprints, which can be deconvoluted. An extended suite of crude oils from several locations in Australia was analysed for their methylated naphthalene content. It was shown that three ratios of selected isomers, each reflecting the same underlying sedimentary reactions, are linearly related to each other when thermal stress has been the only factor controlling the distribution of methylated naphthalenes. This internal consistency allows for an assessment of maturity independent of source, age and location of the crude oil. When the relationships between the three ratios are not linear, secondary processes such as mixing, biodegradation or migration contamination have affected the crude oil. Close examination of the distribution of methylated naphthalenes can reveal the extent to which either of these processes has affected the oil.

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Geochemical characteristics of aromatic hydrocarbons in saline lacustrine crude oils and their significance as exemplified by the south area of western Qaidam Basin

Chinese Journal of Geochemistry ◽

10.1007/s11631-012-0599-6 ◽

2012 ◽

Vol 31 (4) ◽

pp. 476-484 ◽

Cited By ~ 1

Author(s):

Xiaoye Mo ◽

Min Zhang

Keyword(s):

Aromatic Hydrocarbons ◽

Qaidam Basin ◽

Geochemical Characteristics ◽

Crude Oils ◽

The South ◽

Western Qaidam Basin ◽

Saline Lacustrine

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ANALYTICAL METHODS FOR POLYNUCLEAR AROMATIC HYDROCARBONS IN CRUDE OILS, HEATING OILS, AND MARINE TISSUES*

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-1975-1-103 ◽

1975 ◽

Vol 1975 (1) ◽

pp. 103-113 ◽

Cited By ~ 13

Author(s):

R. J. Pancirov ◽

R. A. Brown

Keyword(s):

Aromatic Hydrocarbons ◽

Analytical Methods ◽

Parent Compound ◽

Polynuclear Aromatic Hydrocarbons ◽

Crude Oils ◽

Marine Animal ◽

Initial Stage ◽

Heating Oil ◽

Individual Hydrocarbons ◽

Petroleum Oils

ABSTRACT This paper primarily covers the first phase of a project to demonstrate analytical methods in their ability to measure individual polynuclear aromatic hydrocarbons in typical petroleum oils and marine animal tissues. The study of petroleum oils is complete as described herein. Work on marine tissues is in its initial stage as an analytical method is shown to be capable of measuring benz(a)-anthracene and benzo(a)pyrene when added to clams at the 5 parts per billion (ppb) level. Evaluation of results indicate a detectability of 1 ppb. Eleven to sixteen individual hydrocarbons were measured in samples of a South Louisiana crude, Kuwait crude, a No. 2 heating oil, and a Bunker C fuel. These compounds included the principal 3-to 5-ring aromatics found in petroleum and one 6-ring (benzo(ghi)-perylene). The tricyclics (phenanthrene, methylphenanthrenes) were generally present in the highest concentration and covered the range 26–7677 ppm by weight. Four- and five-ring aromatics occurred in the range <0.5–240 ppm. Concentrations of the most widely studied polynuclear aromatic hydrocarbons, benzo(a)pyrene and benz(a)anthracene, were similar to one another being present at 0.6 to 2.8 ppm in the crude oils and heating oil, whereas in Bunker C their concentrations were 44 and 90 ppm, respectively Measurements of benzo(a)pyrene by previous investigators are tabulated and compared with those of this paper. Data are also presented to show that the alkyl-substituted forms of these compounds are present at much higher concentrations than the parent compound itself.

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