二类油层宏观非均质性及对剩余油分布的影响——以大庆长垣萨北三东萨Ⅱ油层组为例

Macroscopic Heterogeneity of Class Ⅱ Reservoirs and Its Influence on Remaining Oil Distribution——An example of S Ⅱ oil group in Sabeisandong of Daqing Placanticline

以岩心、测井、动态分析数据等资料为基础,对大庆长垣萨北三东萨Ⅱ油层组储层宏观非均质特征及对剩余油分布的影响进行研究.针对二类油层储层特点,在研究过程中,充分考虑河道外溢岸砂.研究表明:研究区目的层储层非均质程度中等.层内物性非均质性较弱,SII10+11a小层非均质性相对较强,层内夹层的不连续分布加强储层层内非均质性;平面上孔渗参数分布受沉积相带的控制,物性与砂体的分布有较好的对应关系,整体来看,研究区平面砂体变化快、物性变化较大、具有较强的平面非均质性;层间物性非均质程度较强,层间隔层的不连续分布使储层层间非均质性愈加严重,隔层把油层分成几个含油段,造成油层上下不连通或连通变差,导致储层纵向渗透能力下降,改变了传统韵律性砂体油气富集模式.

Based on the information of core, log, dynamic analysing datas and so on, having a research on the influence of reservoir macroscopic heterogeneity characteristics and distri- bution of remaining oil of SII oil group in Sabeisandong. of Daqing Placanticline. During the study, the reason of spillover shore sand is fully considered for the feature of class Ⅱ reservoirs. The research shows that： the target reservoirs in the study area are moderate heterogeneity. The layer properties heterogeneity is weak, while SII10＋11 a layer is relative strong. Interlay- ers strengthened the heterogeneity in reservoir of discontinuous distribution within the layers. Porosity and permeability parameter distribution is controlled by sedimentary facies of the plane. Physical properties and distribution of sand has good corresponding relation. As a whole, plane of sand in the study area changes quickly, property changes big and has stronger plane heterogeneity; The degree of interlaminar physical heterogeneity is strong, discontinu- ous distribution of interlayer leads reservoir interlaminar heterogeneity more and more severe, the interlayer divided the oil reservoir into several oil bearing segment, causing the upper and lower reservoir disconnected or poor connectivity, leading the ability of vertical penetra- tion of reservoir decline, changed the traditional rhythmic patterns of oil-gas accumulation of sandbodies.