Abstract: The polycyclic aromatic hydrocarbons of three kinds of tertiary brown coals from Guangxi have been characterized in detail. They are composed mainly of aromatic sesqui-, di-, sester-and triterpenoid hydrocarbons, with tri-and tetra-aromatic triterpenoid derived from terrestrial oleanane, ursane and lupane as the predominant species. Secondary in abundance are aromatic sester- and sesquiterpenoid hydrocarbons, but aromatic diterpenoids, most of the regular PAH are found at trace levels only. It indicates that hydrocarbons derived from angiospermare main composition of aromatic hydrocarbon. Three kinds of brown coals are good source rocks that have potential producing aromatic base crude.

Key words: brown coal, aromatic biomarker, source composition

摘要： 总结了广西三盆地3种第三系褐煤的多环芳烃特征，主要包括芳香倍半萜，二倍半萜和三萜类。其中以陆源奥利烷、乌散烷和羽扇烷前生物衍生而来的单芳至四芳三萜烃类为主，芳香二倍半萜，倍半萜次之。但芳香二萜类，大多数常规多环芳烃仅以微量形式存在。结果表明，双子叶被子生源的烃类主要存在于芳烃馏分中，且是其中的主要成分。这些褐煤属于良好的烃源岩，作为未成熟烃源岩，具有生成芳香基油的潜力。

关键词: 褐煤, 芳烃生物标志物, 生源构成