松辽盆地下白垩统层序地层格架及油气勘探方向

SEQUENCE STRATIGRAPHIC FRAMEWORK OF LOWER CRETACEOUS IN SONGLIAO BASIN AND ITS HYDROCARBON EXPLORATION

尽管层序地层立体模式的适应性较差，在陆相盆地中、其原理和方法仍是可用的。根据层序地层学原理，松辽盆地下白垩统可划分出五个不整合（Ｔ５、Ｔ４、Ｔ３、Ｔ１－１、Ｔ０３）以及三个层序。通过综合分析岩芯、测井、地质等资料，确立了首次潮泛面，最大湖泛面。在此基础上，对各层序进行了体系域的划分。层序１为一发育不全的层序，只有低水位体系；层序２、层序３为发育齐全的层序。层序地层研究可进一步明确以往解释的反射界面性质和意义，对各种沉积体（如砂体）的沉积特征及空间展布有更深入的了解。因此，为在松辽盆地中寻找更多后备储量，开展层序地层研究是十分必要的。

Though the adaptability of sequence stratigraphic stereo model is poor,but the principle and the method of the model is still useful for continental basins. According to the principle of sequence stratigraphy, the Lower Cretaceous could be divided into five unconformities (T5,T4, T3, T1-1, T03) and three sequences. Analysed cores,well log and geological data, the first and the maximum lacustrine flooded areas have been defined, and the system realms corresponding to every sequence have been divided.It is proposed that sequence 1 is a incompletely developed one containing only low water level system3 sequences 2 and 3 are completely developed. Through sequence stratigraphic study, one can understand the properties and significance of the reflecting boundary described before Tnore clearly, and can know more about the sedimentary characteristics and spatial distribution of various sedimental bodies(as sandbodies).