摘要
松粉和高岭土混合样品热模拟残渣氯仿抽提物饱和烃馏份中的生物标志物主要是正构烷烃系列化合物,其次是类异戊二烯烷烃、甾族系列、三环二萜烷和五环三萜烷系列化合物,检测出少量烷基环己烷系列、异构烷烃系列和类胡萝卜烷系列生物标志物。各类地球化学指标显示松粉热解排烃呈现150℃～250℃和300℃～400℃两个高峰期,前期生烃物质可能来源于孢粉质和孢粉壁中的类脂物,后期主要来源于孢粉外壁中的孢粉素,后期的排烃量大于前期。正构烷烃在原样和各温度点样品中均可检出,碳数分布为nC14～nC36,以nC23以后高碳数占优势为特征。类异戊二烯烃碳数分布为C18和C21,植烷优势明显。甾族系列标志物检出于500℃以前样品,C29和C28甾烷相对丰度最高,且以C29>C28和ααα20R>ααα20S为特征。三环二萜烷和五环三萜烷在低于250℃和高于400℃的样品中可明显检出。
Thermal simulation experiments of the mixed sample of pine pollens and kaolinites had been completed. The biomarkers of saturated fractions from the remains extracts mainly are n alkane series, and the secondary compound series are isoprenoid alkane, sterane, Tricycic diterpane and pentacyclotriterpane. The minor component series are alkylcyclohexane, isoalkane and carotane. Various geochemical indexes indicated that there are two peak stages in the process of the pollens pyrolysis, that is 150℃～250℃ stage and 300℃～400℃ stage. During the first evolutionary stage bleeding hydrocarbons probably come from the lipoid in sporopollen cytoplasm and walls, whereas during the second evolutionary stage they might mainly be derived from sporopollenines in outer walls of sporopollens. More plentiful hydrocarbon was generated in second stage. N alkanes were identified from the original and all the simulation samples, the distribution is from n C 14 to n C 36 and the n alkanes of high carbon number (> n C 23 ) occurred more abundantly. The distribution of isoprenoid alkane is from C 18 to C 21 , and it is of sharp phytane superiority. Sterane series biomarkers were separated from the simulation samples below 550℃. The relative contents of C 28 and C 29 steranes are the highest and C 29 >C 28 and ααα 20 R > ααα20S are the important characteristics. Tricyclic diterpane and pentacyclotriterpane were found from the samples below 300℃ and over 400℃. They maybe originated separately from the cytoplasm and outer walls of sporopollens. C 29 , dianorhopane and γ lupane are important biomarkers of continental oils and source rocks. Both also were found in some thermal samples. Alkylcyclohexane and carotane mainly be derived from the products of pyrolysis and ruptures of β carotene in sporopollenines of the outer walls.
出处
《沉积学报》
CAS
CSCD
北大核心
1999年第4期644-650,共7页
Acta Sedimentologica Sinica
关键词
松粉
热模拟
残渣抽提物
饱和烃
生物标志物
pine pollen thermal simulation remains extract saturated hydrocarbon biomarker
