白音查干凹陷南部斜坡带白垩系层序地层及其与油气藏的关系

SEQUENCE STRATIGRAPHY AND HYDROCARBON PATTERN OF CRETACEOUS IN THE SOUTH SLOPE AREA OF BAIYINCHAGAN DEPRESSION

运用层序地层学的原理与方法 ,对白音查干凹陷西部地区南部斜坡带白垩系进行了地层单元的划分 ,并在此基础上研究了沉积体系的展布与演化特征 ,建立了斜坡带层序地层充填模式。以勘探程度相对较高的达尔其地区为例 ,进行了层序地层、沉积微相与地层含油性的分析 ,论述了它们之间的内在联系 ,揭示了本区地层含油性受主要层序地层界面与沉积微相带的双重控制。建立了本区斜坡带油气藏形成与分布模式 ,为下一步地质勘探提供了依据。

According to the principles and techniques of sequence stratigraphy, the sequence of lower Cretaceous in the south slope at west Baiyinchagan depression is divided into three parts. The distribution and evolution of sedimentary systems are analyzed, and a sequence stratigraphic model is built. Taking Daerqi area with more mature exploration level as an example, sequence stratigraphy, micro-sedimentary facies and oiliness of Cretaceous are discussed. The relationship among these factors is summarized. It is indicated that the oiliness in this area is controlled by both first or maximal flooding surfaces and micro-sedimentary facies. A pattern model of formation and distribution of oil and gas reservoir in this area is developed. Some ideas for the further exploration are provided.