敦密断裂带盆地群油页岩特征及成矿差异分析

古近纪敦密断裂带上分布一系列的含油页岩盆地群。根据盆地间构造-沉积充填、岩石组合和油页岩赋存特征，初步确认盆地群中油页岩沉积于湖盆鼎盛阶段，均形成于古近系始新统路特阶。盆地群间油页岩矿床特征存在明显的差别，由西南向东北，油页岩厚度逐渐变小，其沉积环境由深湖到半深湖，再到湖沼，而有机质来源则由湖泊生物为主，到湖泊生物和陆源有机质双向来源，过渡为以陆源高等植物为主。结合含油页岩层系形成于同一时期和相似的古气候背景下，盆地沉降和沉积充填作用是影响油页岩矿床差异的关键因素。长期处于欠补偿环境，可容纳空间大的湖盆利于巨厚油页岩的形成，随着可容纳空间的减少、陆源碎屑供给的增多，油页岩厚度减薄，分布也变得相对局限。深湖和湖沼成因油页岩品质较好，半深湖油页岩品质较差。

Research on Oil Shale Features and Metallogenic Differences in Dunhua-Mishan Fault Zone Basins

Several oil shale-bearing basins are distributed in the Dunhua-Mishan fault zone in Northeast China. The characteristics of tectonic and sedimentary filling evolution, sedimentary association, the occurrences of oil shale and coal indicated that oil shale deposited in the heyday of the lakes, while the sedimentary age of oil shale layers was the Paleogene Eocene Lutetian Stage. While oil shale have displayed certain differences among these basins, from southwest to northeast direction of this fault zone, the thickness of oil shale becomes smaller, and sedimentary environment changed from deep lake to semi-deep lake, and limnetic finally. Meanwhile, the organism sources was dominated by aquatic organism in the southwest part basins, and it became a mixture of terrestrial and aquatic organic matter in the middle part of this fault zone, whereas organic matter of northeast part basins in the fault zone originates mainly from land plants. Combined oil shale layers developed in the same age and similar paleoclimate, tectonic subsidence and sedimentary filling were the key factors on controlling the differences of oil shale in these basins. Perpetual underfilled sedimentary environment and large accommodation promoted huge thick high quality oil shale developed. With the decreasing of accommodation and increasing terrigenous debris supply, the thickness of oil shale thinned and distributed sparsely, while grade of deep lake and limnetic oil shale was high and semi-deep lake oil shale was low.