摘要
对安徽巢湖地区平顶山和马家山剖面下二叠统栖霞组和下三叠统南陵湖组进行了地层沉积特征及暗色石灰岩生烃潜力的综合分析,并对这两个层位的样品进行了饱和烃生物标志物特征研究。结果表明,两个层位的石灰岩都属于有效烃源岩,均具有一定的生烃潜力。南陵湖组石灰岩饱和烃以高丰度的长链三环萜烷、重排藿烷、重排甾烷为特征,表明其形成于偏弱氧化的沉积环境。栖霞组沉积期水体能量相对较低,受陆源物质影响明显,栖霞组石灰岩萜烷系列为常规的分布模式,但其甾烷成熟度参数明显低于平衡值,认为高的热演化程度是造成栖霞组石灰岩20S/(20S+20R)-ααα-C29甾烷值和ββ/(ββ+αα)-C29甾烷值"倒转"的主要原因。
It is known that the classical and well-outcropping Lower Permian Qixia limestone and Lower Triassic Nanlinghu limestone develop at Pingdingshan and Majiashan outcrops in Chaohu, Anhui province, between which the Pingdingshan outcrop is the first-choice one of the Lower Triassic Induan-Olenekian boundary of GSSP in China. The outcrop samples were adopted from these outcrops for analyzing biomarkers in saturated hydrocarbon. The analysis result indicates that both the dark Qixia and Nanlinghu limestones are of effective source rock with a certain hydrocarbon generation potential. The Nanlinghu limestone is characterized by high abundance of long-chain tricyclic terpane, rearranged hopane and diasterane in saturation hydrocarbon, which implies an environment of weak-prone oxidization during sedimentation. Owing to the influence of low-energy terrigenous sediments, the Qixia limestone is characteristic of terpane series in a normal distribution patter, while the sterane shows an obviously lower maturity parameter than the balance value of it. It is suggested the reason why the Qixia limestone presents high thermal evolution just is the inversion of 20S/（20S＋20R）-ααα-C29 sterane and ββ/（ββ＋αα）-C29 sterane values.
出处
《海相油气地质》
CSCD
北大核心
2015年第2期21-28,共8页
Marine Origin Petroleum Geology
基金
国家科技重大专项课题"中上扬子海相碳酸盐岩成藏条件与有利勘探区带评价研究"(编号2011ZX05004-001-004)资助
