木栓质体是我国南方树皮煤的主要显微组分,在西北地区侏罗系煤层中也具有相当高的含量,是一种早期生油的显微组分,对煤成油和未熟-低熟油气的形成具有重要贡献.本文通过对被子植物栓皮栎周皮木栓组织的细菌降解和加水热模拟实验研究,系统地探讨了显微组分木栓质体的生物先质——木栓质的成烃演化过程,结果表明:木栓质可以被细菌降解,并具有两次热解油气生成高峰,分别相当于镜质组反射率0.35%～0.5%和0.8%～1.1%左右.角质体和树皮体的自然演化系列和热模拟实验结果也具有相似的特点.我们认为:①木栓质体的生烃潜力并没有在传统的“油窗”之前就消耗殆尽,在较高演化阶段仍然具有一定的油气生成潜力；②木栓质体的热演化特征可以由木栓质的类脂特性来解释,现代植物木栓组织的化学结构特征和宏观大分子热稳定性的差异是显微组分木栓质体热降解多阶段生烃的主要原因；③木栓质热演化早期生成的液态油以含氧的胶质化合物为主,晚期则生成大量的C12+的高蜡油.%Coals and terrigenous sediments with suberinite dominant in organic macerals have been reported to generate certain amount of low mature and high waxy oils. Evolution and mechanism of the generation, however, is not well constrained due to difficult separation and enrichment of the suberinite from geological samples. This issue was addressed in this paper, by using periderm cork tissues of modern angiosperm Quercus Suberus - a bio-precursor of the suberinite-in bacterial degradation and hydrous thermal simulation experiments. It is showed that the suberin has a multi-stage hydrocarbon generation history. Hydrocarbon generated in bacterial degradation is mainly gas, while is mainly oil in thermal simulation. The oil is greater in amount and generally has two generation peaks, corresponding to Vro at 0. 35%~0. 5% and 0. 8%~1. 1% respectively. The early-generated oil is predominated by oxygenated gum compounds, while the late-generated oil is mainly C12+ high waxy. These features are due to the lipid nature of the suberin. Chemical composition, structure and thermal stability heterogeneity of molecules in the suberin is fundamentally responsible for the multi-stage thermal degradation and hydrocarbon generation.
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