辽西建昌盆地油页岩发育特征及沉积环境

辽西地区建昌盆地含有丰富的油页岩资源。利用野外露头、钻井和化验分析等资料，分析油页岩分布、岩石学特征、地球化学特征和沉积环境。研究表明：油页岩发育于下白垩统九佛堂组一段、二段和三段，共计9个矿组，九佛堂组三段油页岩平均含油率高、厚度大；建昌盆地油页岩平均含油率为5.15%，平均灰分质量分数可达81.9%，平均发热量为5.19 kJ/g，全硫质量分数低，属于中品位高灰分中高发热量低硫型油页岩，开发时对环境污染小；碱厂、五家子、九佛堂、七道泉子和敖汉旗大青山含矿区累计油页岩查明技术可采资源8.22×10⁸ t，油页岩油查明可回收资源3.17×10⁷ t，建昌盆地预测油页岩资源9.27×10¹⁰ t。有机地化特征显示，建昌盆地油页岩有机质丰度较高，有机质类型主要为Ⅰ型和Ⅱ₁型，成熟度较低，处于未成熟—低成熟阶段。九佛堂组时期气候温暖湿润，来源于陆地和湖泊的有机质大量沉积于淡水—咸水的湖泊中，水底为还原环境，有利于有机质的保存。

Oil Shale Features and Sedimentary Environment in Jianchang Basin,Western Liaoning Province

Jianchang basin, located in western Liaoning Province, is rich in oil shale resources. Based on the data of outcrops, drilling and laboratory analyses, distribution and petrological characteristics, the geochemical characteristics and sedimentary environment of oil shale were analyzed. The study shows that the oil shale is in the first, second and third members of Jiufotang Formation, totally nine ore groups. The average oil content and thickness of the third member of Jiufotang Formation are better than those of others. The average oil content of the oil shale is 5.15%, the average ash content is 81.9%, the total sulfur content is low, and the average calorific value is 5.19 kJ/g, belonging to medium-high calorific oil shale. The technically identified recoverable resources of oil shale and shale oil are 8.22×10⁸ t and 3.17×10⁷ t respectively in the area of Jianchang, Wujiazi, Jiufotang, Qidaoquanzi, and Daqingshan. It is predicted that there is 9.27×10¹⁰ t oil shale resources in Jianchang basin. There are abundant organic matter in immature-low mature stage, mainly type Ⅰ and type Ⅱ₁. During Jiufotang Formation, the climate was warm and humid, a large quantity of organic matter from land and lakes were deposited, and the sedimentary environment was in the state of freshwater and brackish reduction, which was conducive to the preservation of organic matter.