Abstract: On the basis of the principles of tectonic and base-level analysis,the depositional characteristics of the Cretaceous system tracts in Songliao Continental Basin was investigated by using high-resolution seismic sections,log curves and lithofacies data. The reservoir prediction,litho-stratigrophic trap analysis with several geophysical methods and the practical exploration show that the sandstones distributed in channel of delta,mouth bar,distal bar in the delta front belt and lake-floor fan are favorable for oil bearing. The exploration for oil and gas in Dabusu area is a typical example for exploration of subtle reservoir. It has a great significance for oil and gas exploration in the western slope of Songliao Basin.

Key words: subtle reservoir, reservoir prediction, system tract, structural slope-break zone, sequence stratigraphy

摘要： 基于构造层序与基准面分析原理,利用高分辨地震、测井、岩相等资料重点研究了白垩纪松辽湖盆各体系域的沉积特征。应用多种地球物理手段在体系域内进行的储集层预测、岩性-地层圈闭分析及勘探实际表明,本区发育在湖扩展域和高位域的三角洲前缘河口坝、远砂坝以及湖底扇等各类砂体,对形成隐蔽油气藏最为有利。大布苏地区勘探实例可以作为隐蔽油藏勘探的典型,对广阔的松南西部斜坡区下步勘探具有借鉴意义。

关键词: 隐蔽油气藏, 储层预测, 体系域, 构造坡折带, 层序地层学