关键词: 巨厚砂岩, 中生界储层, 流动单元, 大港油田

Abstract:

Taking the example of the Mesozoic reservoir in fault block Guan 142  of Huanghua depression, this article discusses the methodology of flow units in thick sandstone reservoir. The research of flow units in such reservoirs can be divided into two ranks, one is to make sure the distribution of seepage barrier, the other is to analyze the differentia of fluid flow in the inner connected sands. The results show that three types of barriers have developed in the fault block Guan 142：pelitic barrier, calcareous sandstone and calcareous glutenite. Through the analysis of differentia of fluid flow, the inner connected sands can be classified  into  three types of flow units, of which type A with wide pore and big throat has good permeable property and high intensity of water injection; type B has middle pore and throat, so the ability of its permeability and water injection takes the second place; type C is the worst flow unit, for it is mainly composed of siltstone or reservoir with loose calcareous cementation, and hence with the worst water injection. Based on the above analysis, the identified model of permeable barriers and the discriminant function of flow units have been set up, which can be applied to forecasting the distribution of residual oil and optimizing the development scheme.

Key words: thick sandstone, Mesozoic reservoir, flow unit, Dagang Oilfield