为弄清古龙页岩储层的岩性、物性及脆性等特征,在古龙凹陷部署了一口全井段取心井——古页8HC井。岩心精描以及元素分析表明,Q1—Q9油层沉积时期,古龙凹陷沉积微相类型主要为半深湖—深湖相,发育了厚层的富有机质页岩,可细分为4种岩性：页岩、粉砂岩、介壳灰岩以及白云岩。按照“构造+岩性”的划分原则,结合岩性含量特征,将岩相划分成4类：纹层状页岩相、夹层状页岩相、块状白云岩相及块状粉砂岩相。古沉积环境为温暖潮湿气候下的淡水—微咸水+弱物源+强还原环境,为有机质形成与保存提供了良好的场所。通过对储集性、含油性以及可压性3项指标综合评价可知,Q1—Q3油层储集空间类型丰富,物性条件好,含油性优越,可压性能满足页岩油施工要求,是目前大庆油田中高熟页岩油勘探的最有利层段。

In order to study the lithology, property and brittleness of Gulong shale reservoir, a whole-section coring well, Well-GY8HC, is deployed in Gulong Sag. Detailed core description and element analysis show that the sedimentary microfacies in Gulong Sag are mainly semi-deep to deep lacustrine facies during the sedimentary period of Q1 to Q9 reservoirs, with thick organic-rich shale developed and can be subdivided into four types of lithology which are shale, siltstone, shell limestone and dolomite. Based on the classification principle of “structure+lithology” and combined with the lithology content characteristics, the lithofacies are divided into four types which are laminated shale, intercalated shale, massive dolomite and massive siltstone. The paleo-sedimentary environment is fresh water-brackish water+weak provenance+strong reduction in warm and humid climate, providing favorable place for organic matter formation and preservation. Comprehensive evaluation of three indexes of reservoir capacity, oil-bearing property and fracability shows that several reservoir space types of Q1 to Q3 reservoirs with good physical property, excellent oil bearing property and efficient fracability for shale oil production, being the most favorable interval for medium and high mature shale oil exploration in Daqing Oilfield.