It is a member of the oleanoid series, which consists of pentacyclic triterpenoids (such as beta-amyrin and taraxerol[verification needed]) where all rings are six-membered.

Oleanane is a pentacyclic triterpenoid, a class of molecules made up of six connected isoprene units.

As mentioned above, they have a characteristic mass fragment at m/z = 191, and thus will appear in the same selected ion chromatograph (SIC) as hopanes.

For example, the ratio of 18-alpha-oleanane + 18-beta-oleanane:17-alpha-hopane in rock extracts (and associated petroleums/oils) has been found to correlate (at least broadly) to the presence of angiosperms in the fossil record.

[4] Lastly, the study introduced the idea of an "oleanane parameter," which could be used in assessing angiosperm input to petroleum sources.

[4] That being said, the presence of angiosperms may not be the only thing affecting the oleanane content of sediments, rock extracts and petroleum.

Despite this, it is still unclear as to how marine influence enhances the expression of oleananes (thus increasing observed concentration).

Some ideas include the changes in pH, Eh and the microbial environment that come with the interaction with seawater.