浊积砂体沉积微相及储层非均质性研究——以东营胜坨油田T74地区古近系沙河街组三段中亚段浊积砂体为例

利用岩心观察、测井相分析、测井资料处理与评价、图像分析等方法,系统研究了胜坨油田T74地区古近系沙河街组三段中亚段浊积砂体的沉积微相及储层非均质性.研究表明,T74地区沙河街组三段中亚段储层由三期浊积砂体叠加形成,可划分为中心微相和边缘微相两种沉积微相带;各期浊积砂体储层非均质性较强,层内非均质性以韵律性不明显、渗透率差异大为主要特征,层间及平面非均质性主要受沉积微相控制,中心微相储层的物性要好于边缘微相;不同沉积相带储层微观孔隙结构存在差异,中心微相主要发育中孔中喉和细孔中喉型孔隙结构,边缘微相主要发育细孔细喉以及微孔型孔隙结构.

Sedimentary Microfacies and Heterogeneity of the Turbidite Sand Bodies: A Case Study in the Middle 3rd Member of the Shahejie Formation in the T74 District of Shengtuo Oilfield, Dongying

Sedimentary microfacies and reservoir heterogeneity of the turbidite sand bodies in the middle 3rd Member of the Shahejie Formation in the T74 district of Shengtuo oilfield were studied systematically based on the core observation, electrofacies analysis, well log interpretation and image analysis. The results show that the reservoir in this member is composed of three stages of turbidite sand bodies, which can be divided into two kinds of microfacies, the central microfacies and the marginal microfacies. The reservoir heterogeneity of the turbidite sand bodies is very significant, and the inlayer heterogeneity is characterized by indistinct rhythmicity and high permeability contrast. The interlayer heterogeneity and areal heterogeneity are controlled by the sedimentary microfacies, and the physical properties of sandbodies in central microfacies are better than those in marginal microfacies. The microscopic pore structure in these two kinds of microfacies is also different. The moderate pores and throats occur typically in the central microfacies, but the minute pores and throats are mainly developed in the marginal microfacies.