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In addition to the hopane family, several other types of triterpanes that are occasionally encountered can be very useful in correlations. Gammacerane is often found in sediments deposited under abnormal salinites, including lacustrine facies. Identification of gammacerane can be difficult, however, both because it is usually only a minor component and because it [ http://www.thefreedictionary.com/elution elutes] at different places with different chromatographic columns.

In addition to the hopane family, several other types of triterpanes that are occasionally encountered can be very useful in correlations. Gammacerane is often found in sediments deposited under abnormal salinites, including lacustrine facies. Identification of gammacerane can be difficult, however, both because it is usually only a minor component and because it [http://www.thefreedictionary.com/elution elutes] at different places with different chromatographic columns.

[[:file:oiloil-and-oilsource-rock-correlations_fig8-28.png|Figure 6]] shows gammacerane in the m/z 191 mass chromatograms of two genetically related oils from southern Sicily. In this example, gammacerane elutes after the C₃₁ homohopanes. Note also the relative increase in the C₃₄ and C₃₅ homohopanes. The presence of gammacerane and the homohopane distribution suggest a strongly reducing, possibly carbonate or hypersaline depositional setting for the source rock of these oils.

[[:file:oiloil-and-oilsource-rock-correlations_fig8-28.png|Figure 6]] shows gammacerane in the m/z 191 mass chromatograms of two genetically related oils from southern Sicily. In this example, gammacerane elutes after the C₃₁ homohopanes. Note also the relative increase in the C₃₄ and C₃₅ homohopanes. The presence of gammacerane and the homohopane distribution suggest a strongly reducing, possibly carbonate or hypersaline depositional setting for the source rock of these oils.