延长地区延长组储层非均质性特征

1.长安大学 地球科学与资源学院,陕西 西安 710064; 2.西安科技大学 期刊中心,陕西 西安 710054; 3.西北水利水电工程有限责任公司,陕西 西安 710077

延长组; 储层非均质性; 沉积作用; 延长地区

Reservoir heterogeneity characteristics of Yanchang Formation in Yanchang Region
MA Dong-sheng1,FU Chao-feng1,LI Ke-yong2,

(1.College of Earth Science and Resources,Chang'an University,Xi'an 710064,China; 2.Journal Center,Xi'an University of Science and Technology,Xi'an 710054,China; 3.Northwest Water Conservancy and Hydropower Engineering Co.,Ltd.,Xi'an 710077,China)

Yanchang Formation; reservoir heterogeneity; sedimentary effect; Yanchang Region

DOI: 10.13800/j.cnki.xakjdxxb.2017.0617

备注

为了研究延长地区延长组储层非均质性特征,通过宏观和微观2方面,根据测井资料、岩心观察、岩心分析化验资料、压汞测试等方法对影响储层非均质性的各项参数进行了讨论。研究认为,粒度分布的韵律性对纵向上储层非均质性具有一定的控制作用; 粒度均一的部位物性较好,层理构造密度较大的层段物性较差,隔夹层越薄,分布范围越小,油气越容易发生垂向运移,隔夹层对油气在纵向上的分布起重要影响; 层内非均质性可用渗透率变异系数、突进系数、级差等参数进行评价,层间隔层对流体运动起隔挡作用; 储层砂体的平面连续性及物性是控制储层非均质性的重要因素,三角洲水下分流河道砂体构成了延长地区延长组含油砂体的基本骨架,主流方向上砂体呈条带状分布,砂体在所处的相带不同,表现出不同的连通性和非均质性; 成岩过程中原生孔隙与后期改造形成的次生孔隙控制着油气进入储层的饱满程度。分析认为,延长地区延长组储层非均质性特征表现为粒度韵律、层理构造、隔夹层、渗透率、砂体几何形态、孔隙结构等因素的不均一性。

In order to study the reservoir heterogeneity characteristics of Yanchang Formation in Yanchang Region,from the macroscopic and microscopic aspects,according to the logging data,core observation,core analysis dataand mercury testing method,we discuss the influence ofparameterson reservoir heterogeneity.The results show that the rhythm of the particle size distribution has a certain control effect on the reservoir heterogeneity in the vertical direction.The site of particle size uniformity is better,the layer of the larger stratified structure density has poorer physical properties,the thinner the interlayer,the smaller the distribution,the more prone to vertical hydrocarbon migration,theinterlayer has on important influence on thedistribution of oil and gas in the vertical.The heterogeneity of the layers can be evaluated by the parameters such as permeability coefficient of variation,splitting coefficient and step difference.The interlayer acts as a barrier to fluid movement.The planar continuity and physical properties of reservoir sand bodies are important factors to control reservoir heterogeneity.The sandbody of delta underwater distributary channel constitutes the basic skeleton of oil-bearing sandbody in Yanchang Formation.The distribution of sand bodies in different phases shows different connectivity and heterogeneity.The secondary porosity formed by the primary porosity and the later transformation in the diagenetic process controls the full extent of the oil and gas entering the reservoir.We believe that the reservoir heterogeneity of the Yanchang Formation in Yanchang Region is characterized by the inhomogeneity of the factors such as grain size rhythm,stratified structure,interlayer,permeability,sand body geometry and pore structure.