喇嘛甸油田北东一区萨Ⅱ组隔夹层识别及分布特征研究

Study on Identification and Distribution Characteristics of Interlayer in SaⅡFormation in the First Area of Northeast of Lamadian Oilfield

碎屑岩储层中关于隔夹层的研究成果与认识,对于历经多年开采老油田的剩余油深度挖潜与可持续开发具有重要意义。以喇嘛甸油田萨Ⅱ组为例,基于储层构型分析原理、岩性-物性分析以及测井识别方法,深入分析和探讨了隔夹层的成因类型、发育特征、测井识别标准以及分布特征。研究结果表明:(1)依据储层构型原理,萨Ⅱ组内隔夹层可划分为小层间隔夹层、单砂体间隔夹层和单砂体内夹层3个层次;从成分成因角度可进一步划分为泥质隔夹层、物性隔夹层和钙质隔夹层3种成因类型。(2)优选不同类型隔夹层的敏感性测井曲线,建立了3类成因隔夹层的定性-定量识别标准。(3)萨Ⅱ组单砂体间(或内)夹层较为发育,频率和密度对应关系良好,层内非均质性较强,夹层分布频率在0.364~0.754层/m之间,夹层分布密度在0.067~0.137 m/m之间。(4)小层间隔层追踪性、连续性强,厚度大,油气阻挡效果好;单砂体间夹层仅在小范围连续分布,对局部流体起阻拦作用;单砂体内夹层呈零星分布,厚度最薄,封隔油气能力有限。

Research results and understanding of interlayers in clastic reservoirs are of great significance to the deep tapping potential and sustainable development of remaining oil in old oilfields after years of exploitation.In this paper,Lamadian oilfield formation SaⅡis taken as an example,based on the principle of reservoir architecture analysis,lithology-physical property analysis and logging identification methods,the genetic types,development characteristics,logging identification criteria and distribution characteristics of interlayers are deeply analyzed.The study shows that:(1)According to the principle of reservoir configuration,The interlayer within the SaⅡformation can be divided into three layers:interlayer between sublayers,interlayer between single sandbodies and interlayer in single sandbody,and can be further divided into the muddy interlayer,physical property interlayer and calcareous interlayer from the perspective of compositional origin;(2)The sensitivity logging curves of different types of barriers and interlayers are optimized,and the qualitative and quantitative identification criteria of three types of genetic interlayers are established;(3)The interlayer between(or within)the single sand body of the SaⅡformation is relatively developed,the corresponding relationship between frequency and density is good,and the heterogeneity within the layer is strong.The interlayer distribution frequency is between 0.364 layer/m and 0.754 layer/m,and the interlayer distribution density is between 0.067 m/m and 0.137 m/m;(4)Small interlayers have strong tracking and continuity,large thickness and good oil and gas blocking effect,and the interlayers between single sand bodies are only distributed continuously in a small range.It plays a role in blocking local fluid.Interlayers in single sand body are distributed sporadically.The thickness is the thinnest,and the ability to seal off oil and gas limited.Therefore,it would provide a certain geological basis for the deep development of Saertu oilfield and tapping the potential of remaining oil.