摘要
鄂尔多斯盆地上古生界煤系烃源岩中重排藿烷类化合物异常丰富,经GC/MS分析,检测出17α(H)-重排藿烷系列相对丰度最高,这类化合物以C30重排藿烷为主峰,C29重排化合物次之,分布模式与正常藿烷类似。从烃源岩的生源构成、沉积环境的氧化还原性和有机质的热演化程度3个方面来探讨高丰度的17α(H)-重排藿烷的成因。研究表明,烃源岩中高丰度17α(H)-重排藿烷的母质来源可能是低等水生菌藻类弱氧化-弱还原、微咸水的扇缘泥炭沼泽相有利于高丰度17α(H)-重排藿烷形成;其形成不完全取决有机质的热演化程度。
The upper-Palaeozoic coal-bearing source rocks in north Ordos Basin were found to be extremely rich in rearranged hopanes. By GC/MS analysis, the highest relative abundance of rearranged hopane series is 17α(H)-diahopanes. The main peak of this class of compounds is the C30-diahopane. The abundance of C29-diaho- pane is lower than the abundance of C30-diahopane. 17α(H)-diahopanes show a similar distribution pattern with regular hopanes. The main controlling factors of extremely abundant 17α(H)-diahopanes are discussed from the composition of organic materials, maturity and oxidation reduction of depositional environments. The result shows the source of parent material of high abundance of 17α(H) -diahopanes in source rocks may be low aquatic alage. Weak oxidation to weak reduction and brackish weak fan marginal peat bog facies is beneficial to the high abun- dance of 17α(H)-diahopanes formation. The origin and accumulation of 17α( H)-diahopanes do not entirely de- pend on the maturity of the organic matter.
出处
《科学技术与工程》
北大核心
2015年第15期27-32,43,共7页
Science Technology and Engineering
基金
国家自然科学基金(41272170)
国家科技重大专项(2011ZX05007-001)资助