赵石窑河道砂体储集特征

赵石窑河道砂体成分成熟度和结构成熟度均较低,岩屑和长石含量较高,泥质、硅质、铁质和碳酸盐为主要填隙物,经历了同生、埋藏和表生3个成岩阶段。粒度是造成储层岩性相孔渗性差异的主要原因,可识别出8种孔隙类型和大孔-中喉、大孔-细喉、中孔-细喉和微孔-微隙型Ⅳ种孔隙结构,孔隙结构及分布与粒度和填隙物密切相关。曲流点坝相中下部孔渗性最好,底部次之,顶部及边缘最差。

RESERVOIRING PROPERTY OF RIVER CHANNEL SANDBODIES IN ZHAOSHIYAO AREA

The river channel sandbodies in Zhaoshiyao area are characterized by low compositional maturation and low textural maturation,high debris and feldspar contents.The filling materials of the sandbodies are mainly argillaceous,siliceous,iron substance and carbonatite.The sandbodies underwent three diagenetic periods such as syngenetic,burial and epidiagenetic periods.Their porosity and permeability are closely related to their granularity.The porosity of the sandbodies could be classfied into 8 pore types and 4 kind of pore textures.The pore textures are related to the granularity and the filling materials.It has been proved by study that the mid and lower parts of the meandering river point bars usually have the best porosity and permeability,the bottom part is secondary and the top and marginal parts ane the worst.