Hydrocarbon Composition of the Late Proterozoic Oils of the Siberian Platform: Implications for the Depositional Environment of Source Rocks
Hydrocarbon Composition of the Late Proterozoic Oils of the Siberian Platform: Implications for the Depositional Environment of Source Rocks
复制标题
西伯利亚地台晚元古代石油烃组成：对烃源岩沉积环境的启示
DOI：
10.1007/978-3-642-76884-2_22
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发表时间：
1992
影响因子：
--
通讯作者：
T. Powell
中科院分区：
文献类型：
--
作者：
R. Summons;T. Powell
寒武系和晚元古界海相碳酸盐岩及西伯利亚地台陆源碎屑岩中的油气来源可能是深埋的里芬期盆地页岩，也可能是晚元古界至早寒武世的碳酸盐岩/蒸发岩陆架沉积物。该地区3个油田的油类烃组成非常相似，具有明显的特征：无环类异戊二烯相对丰度高，Pr/Ph < 1；ααα和αss甾烷相对丰度高，几乎不存在重排甾烷；29,30-双去甲藿烷和去甲藿烷相对于藿烷丰度高；28,30-双去甲藿烷、2α-甲基藿烷和其他罕见的三萜含量高；芳基类异戊二烯的存在。这些方面的生物标志物分布与显生宙的碳酸盐岩和碳酸盐岩/蒸发岩的分布相似，并与沉积岩性有关，因为它们与这些沉积环境中普遍存在的生物和化学条件有关。因此，这些西伯利亚台地油可能来自于文甸/寒武纪碳酸盐岩层序。
Oils reservoired in Cambrian and Vendian (Latest Proterozoic) marine carbonates and terrigenous clastic rocks of the Siberian Platform could have been sourced either by deeply buried basinal shales of Riphean age or, by carbonate/evaporite shelf sediments of Latest Proterozoic to Early Cambrian age. The oils from three fields in the region all have very similar hydrocarbon compositions which include the following distinctive features: high relative abundance of acyclic isoprenoids and Pr/Ph < 1; high relative abundance of ααα and αss steranes and virtual absence of rearranged steranes; high abundance of 29,30-bisnorhopane and norhopane relative to hopane; high abundance of 28,30-bisnorhopane, 2α-methyl hopanes and other unusual triterpenoids; and the presence of aryl isoprenoids. These aspects of the biomarker distributions are similar to those found in some carbonates and carbonate/evaporites from the Phanerozoic and evidently correlate with sediment lithology because they relate to biological and chemical conditions prevailing in these depositional environments. Thus, these Siberian Platform oils have likely been sourced within the Vendian/Cambrian carbonate sequence.