摘要
本文为昆明盆地新生代沉积有机质研究的一部分。着重讨论参3孔晚新生代沉积物中甾类、萜类生物标志化合物的组成、构型和分布,进而分析这些特征与沉积物类型及埋藏深度等之间的关系。通过这些研究,对于探讨内陆淡水湖盆沉积有机质中生物标志化合物的特征和早期演化、陆相沉积有机质的生源物性质与特征、再现内陆淡水湖盆沉积有机质的成烃模式,无疑是有重要意义的。
Abstract
In this paper, the biomarker compounds (Steroids and terpenoids) in the extracts from Late Cenozoic sediments in the Chan 3-boring hole are studied by means of GC-MS. The Chan 3-boring hole is located at the eastern margin of Dianchi Lake in Kunming Basin. The Cenozoic sediments in the hole mainly consist of weakly consolidated sands, silts and clays with peat and brown coal seams, up to 516 m thick. The primary study of biomarker compounds shows that the composition, structure and distribution of biomarker compounds in the sediments are obviously different from those in source rocks and crude oils. Higher abundance of 17β(H), 21β (H) hopanes, and 5α(H), 14α (H), 17α (H), 20R-steranes and the presence of a lot of steranes and terpenes in these samples indicate that they are immature. There is no relationship between the characteristics of biomarker compounds in the sediments and the burial depth. This completely reflects the evolutionary level of organic matter in the sediments. But the relative amount of ββ-hopanes in the sediments tends to decrease gradually with increasing of depth, thus it can be considered as a more effective index for thermal evolution. The distributions of carbon number in steranes and terpanes are controlled by the types of the sediments. Relative amounts of C29 steranes and C27 hopanes in the carbonaceous mud and brown coal are larger than those in argillaceous sediments. It is interesting to note that the distributions of carbon number in ααα R-Sterancs series and αααR-Sterenes series are similar.
论文详情