东营凹陷西部沙四上亚段滩坝砂体有效储层的物性下限及控制因素

The Petrophysical Parameter Cutoff and Controlling Factors of the Effective Reservoir of Beach and Bar Sandbodies of the Upper Part of the Fourth Member of the Shahejie Formation in West Part of Dongying Depression

滩坝砂体是东营凹陷西部沙四上亚段主要沉积储层。综合运用实测物性、解释物性、试油、压汞等资料,分别利用分布函数曲线法、试油法、束缚水饱和度法求取了沙四上亚段滩坝砂体不同深度下有效储层的物性下限,运用回归分析方法求取了物性下限与深度之间的函数方程。在物性下限研究的基础上,结合滩坝砂体沉积特征、成岩作用特征、地层压力特征等研究,探讨了有效储层发育的控制因素。研究区滩坝砂体的有效性主要受沉积微相和厚度的控制,其中坝主体和滩脊微相是有利储层发育区,而成岩作用和地层压力对砂体有效性的影响弱于沉积微相对砂体有效性的影响。

Beach and bar sandbodies are main sedimentary reservoir of the upper part of the fourth member of the Shahejie formation （Es4^s） in the west part of Dongying depression. Based on the comprehensive application of physical properties, oil production test, and mercury injection data, the petrophysical parameter cutoff of effective reservoir of beach and bar sandbodies of Es4^s is determined by distribution function curve method, production test method, and irreducible water saturation method, and the functional equation between petrophysical parameter cutoff and depth is obtained. On the basis of the research of petrophysical parameter cutoff, combining the analysis of sedimentary characteristics, diagenesis characteristics and reservoir pressure characteristics of beach and bar sandbodies, the control- ling factors of effective reservoirs are discussed. Sedimentary micro-facies and thickness are main controlling factors, and the effective reservoir is the most developed in the micro-facies of bar main body and beach ridge. It is not obvious that the diagenesis and reservoir pressure influence physical properties of reservoir.