鄂尔多斯盆地太阳湾油区长2 储层非均质性研究

储层非均质性是影响剩余油分布的重要因素之一。 近年来，太阳湾油区剩余油滞留现象严重。 针对这一现象，结合该区实际地质情况，利用区内岩性、物性、电性及含油性等资料，定性评价该区长 2 储层非均质性及其成因，并分析非均质性对储层剩余油分布的影响。 采用实验、测井及标准对比等方法，将区域非均质性分为层内、层间、平面和微观非均质性 4 类进行探讨。 结果表明：研究区层内非均质性较强，主要受沉积构造、粒度韵律、渗透率非均质性及夹层分布等因素的控制；层间非均质性总体较强，各小层发育不均一，长 2³ 小层层间非均质性相对最强，长 2² 和长 2¹ 小层次之；平面非均质性受砂体及沉积微相展布影响较大；微观上孔隙结构复杂，各种成岩作用加剧了储层非均质性程度。通过对储层非均质性的研究，可以为掌握研究区剩余油分布状况及后期勘探开发提供重要依据。

Research on heterogeneity of Chang 2 reservoir in Taiyangwan area,Ordos Basin

Reservoir heterogeneity is one of the important factors that affect remaining oil distribution. In recent years, retention phenomenon of remaining oil in Taiyangwan area is serious. In view of this phenomenon, accorded to the practical geological situation, geological data of lithologies, physical properties, electric properties and oiliness were adopted to conduct qualitative evaluation of Chang 2 reservoir heterogeneity and its cause, and to analyze the influences of heterogeneity on remaining oil distribution of the reservoir. By using experiment，logging and standard contrast methods, this paper divided heterogeneity into the intra-layer, inter-layer, plane and microscopic heterogeneities for respective discussion. The result shows that the intra-layer heterogeneity is strong in the study area, which is mainly controlled by sedimentary structure, rhythm, permeability and interlayers; inter-layer heterogeneity is generally strong with uneven development in each layer, the heterogeneity of the Chang 2³ is the strongest, followed by Chang 2¹ and Chang 2²; the plane heterogeneity is mainly affected by the distribution of sand body and sedimentary microfacies; pore structure at micro level is complex, and various diagenesis heightened reservoir heterogeneity degree. The research of the reservoir heterogeneity provides important theory basis for grasping the distribution of remaining oil and later exploitation in the study area.