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在对低热烃源岩萜类标志物的研究中，检测到一些五环三萜类化合物，其分布型式可分为４类；Ａ型具有高丰度的五环三萜烯；Ｂ型具有高丰度的Ｃ３１藿烷；Ｃ型以具有相对高含量的重排藿烷和３０－降新藿烷（Ｃ２９Ｔｓ）为特征；Ｄ型则以Ｃ３０－未知三萜烷ＵＣＴ２和相对较高含量的Ｃ３５藿烷为特征。这些五环三萜类的分布型式受生源、成岩环境和成熟度等因素的影响而差异较大，因而可以提供有关烃源岩的地球化学信息。结合源岩的其他地球化学特征推测：Ａ型表明源岩处于成熟度极低的演化阶段；Ｂ型、Ｃ型表明源岩形成于弱氧化至弱还原条件下；Ｄ型则表明源岩与半咸水－咸水的强还原环境有关，其中Ｃ３０－未知三萜烷ＵＣＴ２的存在可能指示该环境中某种特殊生源母质的输入。文中还对五环三萜类化合物的生源与演化进行了讨论。
In the research on terpene markers of low-temperature source rocks, some pentacyclic triterpenoids were detected and their distribution patterns can be divided into four types; type A has a high abundance of pentacyclic triterpenes; type B has high Abundance of C31 hopane; C type is characterized by a relatively high content of rearranged hopane and 30-norene (C29Ts); D type C30-unknown triterpenoid UCT2 and relatively high content of C35 Hopane is characterized. The distribution patterns of these pentacyclic triterpenoids are greatly different from those of source rocks, diagenetic environments and maturity, which can provide geochemical information on source rocks. According to other geochemical characteristics of source rocks, Type A indicates that source rocks are in an evolutionary stage with extremely low maturity. Type B and C indicate that source rocks are formed from weak oxidation to weak reduction. Type D indicates that source rocks and half The strong reduction of saltwater-brackish water is related to the environment, in which the presence of C30-unknown triterpenoid UCT2 may indicate the importation of a particular parent material in this environment. The author also discussed the origin and evolution of pentacyclic triterpenoids.