摘要
有效烃源岩的概念和应用需要实践的验证。济阳坳陷油气勘探已有 40年历史 ,积累了研究有效烃源岩的大量地质地球化学资料。综合利用前人的研究成果 ,根据大量样品分析和地质研究 ,认为沙四段上部盐湖—咸水湖相、沙三段下部咸水—半咸水环境沉积的油页岩、灰质 (含灰质 )泥页岩是济阳坳陷主要油田的原油提供者 ,它们是湖盆因盐度不同而形成分层水体并造成缺氧环境中沉积的 ,有机碳含量多大于 2 % ,有机质性质良好 ,但是由于断陷活动差异性、浊流沉积的事件性和气候多变性 ,缺氧环境不时被打破 ,存在很强的非均质性和分布的区域性。为了真实反映这种有效烃源岩的时空分布 ,提出了以体系域为单元的、按有机碳含量划分 5级烃源岩的评价方法 ,并且讨论了有效烃源岩对油气成藏的控制作用。图 2参
Concept of effective source rock needs to be confirmed in petroleum exploration. It is a very good case study to apply this concept in the Jiyang Depression, as there is great quantity of geological and geochemical data of effective source rocks from this depression after 40 years exploration. Based on previous materials and the geochemical investigations, the oil shales and calcareous shales in the upper part of Es 4 and in the lower part of Es 3 should be the major oil source rocks in the depression. Generally these shales have TOC generally over 2% and contain sapropelic organic matter. The shales of the upper Es 4 were formed in hypersaline (salt lake) to saline lake environments and those of the lower Es 3 were sediments in saline lake to brackish lake. As the anoxic environments were frequently suspended or disturbed by tectonic activities and turbidity currents, the effective source rocks were characterized by great heterogeneities both in their TOC contents and in regional distributions. In order to describe the particular features of the effective source rocks, a new method to evaluate the source rocks is used, in which evaluated units by system tracts and classified the source rocks are divided into 5 levels according to TOC content.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2003年第3期53-55,共3页
Petroleum Exploration and Development
基金
国家"十五"重大科技攻关项目 (2 0 0 1BA60 5A0 9)
关键词
有效烃源岩
沉积特征
地球化学
评价方法
济阳坳陷
effective source rock
sedimentation
geochemical characterization
Jiyang Depression
