徐深气田营四段低渗透巨厚砾岩储层渗流特征

PERCOLATION CHARACTERISTICS OF HUGELY THICK LOW- PERMEABILITY CONGLOMERATE RESERVOIR IN YING-4 MEMBER IN XUSHEN GAS FIELD

大庆徐深气田重要储层之一是营四段低渗透巨厚砾岩储层，其成分主要为火山岩，储集空间类型及渗流特征复杂。通过多种分析测试手段，对研究区及重点井进行了综合研究，揭示了低渗透火山岩巨厚砾岩储层的储集性受岩相、成岩作用和构造运动等因素控制，储集空间包括原生孔隙和裂缝及次生溶孔和裂缝，主要发生了压实、胶结和溶蚀等成岩作用，储层致密、连通性差，为低孔低渗喉道不均匀型储层，具有可动流体饱和度、孔隙度低，束缚水饱和度较高的特点。

The hugely thick low-permeability conglomerate reservoir in Ying-4 Member is one of the important reservoirs in Xushen Gas Field in Daqing. The reservoir mainly belongs to the volcanic rock reservoir, with complex storage space type and percolation characteristics. Using various testing methods, this paper studies the key wells in the studied area comprehensively. The research shows that the storage property of hugely thick low-permeability vol- canic conglomerate reservoir in the area is controlled by the factors, such as rock facies, diagenesis and tectonic movements, the storage space mainly includes primary pores and fractures and secondary dissolved pores and frac- tures, the diagenetic weathering, such as compaction, cementation, corrosion and so on happens, the reservoir is tight and has a poor connectivity, being the reservoir with low porosity and permeability and non-uniform throats, and having the feature of low movable fluid saturation and porosity and high irreducible water saturation.