临南油田隔层类型划分及其分布规律研究

Classification and Distribution of Insulating Layers in Linnan Oilfield

在对临南油田储层砂岩小层及单砂体精细划分对比基础上 ,通过对取心井的岩心观测和测井曲线分析 ,对小砂层之间的隔层进行了系统研究 ,按照岩性、岩相特征划分为 3种主要类型 :泥岩类隔层 (Ⅰ型隔层 )、粉砂岩类隔层 (Ⅱ型隔层 )和钙质岩类隔层 (Ⅲ型隔层 ) .并根据沉积相特点把Ⅰ型隔层分为Ⅰ1型和Ⅰ2 型 ,把Ⅱ型隔层分为Ⅱ1型和Ⅱ2 型 .这些不同类型的隔层在测井曲线形态、沉积组合关系和空间展布上都具有不同的特点 .隔层分布不连续会造成砂层在垂向上局部的相互连通 ,上下砂层为砂坝砂体或河道砂体时 ,形成连通的原因不同 ,也分别具有各自不同的测井响应模式 .根据隔层的岩性、电性特征和建立的连通模式 ,从测井曲线出发 ,对研究区内 110多口井逐一进行了研究 ,最终揭示了隔层的空间展布规律 ,为剩余油预测和优化开采方案提供了依据 .

Based on detailed division and correlation of reservoir sandstones in Linnan oilfield, the insulating layers are systemically studied through core observation and well logging analysis. According to lithology and lithofacies of the layers, they are divided into mudstone insulating layers (typeⅠ), siltstone ones (type Ⅱ) and carbonate-bearing ones (type Ⅲ). Because of facies variation, typeⅠ insulating layers are subdivided into Ⅰ~1 and Ⅰ~2, and type Ⅱ into Ⅱ~1 and Ⅱ~2. All the insulating layers have different well logging features, sedimentary assemblages and spatial distributions. Discontinuity of the insulating layers could make nearby sand layers connected. The connection between sandbar bodies or channel sand ones shows different origins and distinguished well logging models. The spatial distribution characteristics of each insulating layer are concluded by the research of more than 110 well loggings, thus providing basic data for the prediction of residual oil and selection of exploitation methods.