鄂尔多斯盆地西南部Y33区块储层地质建模研究

Research on reservoir geological modeling of Y33 block in the southwest of Ordos Basin

油藏进入开发中后期水淹情况复杂,急需进行油藏精细描述研究,储层三维地质模型作为其核心内容能够反映地质情况且为数值模拟提供可靠数据体。基于已有的地质认识、综合大量地质数据对研究区延7油层组进行储层三维地质建模研究。模型显示:(1)延72砂体在中偏东北及西南部有大面积连续分布;延71砂体在西北部、中偏东北部以及东部局部区域较厚,泥岩夹层较延72略为发育。(2)延71属于低孔中渗储层,延72属于低孔低渗储层,均质程度均为中等;平面上延71高值分布范围较延72大,且高值部位与砂体较厚的区域对应性好,是研究区的有利开发区。经概率分布一致性检验及储量核算验证,对Y33区块目的层建立的储层三维地质模型可靠,能准确反映出储集体的空间展布规律及物性参数的分布特征,可作为后续数值模拟原始数据体,为生产开发提供有利指导。

In the middle and late stages of development,the water-flooding situation of the reservoir is complicated,and it is urgent to conduct a fine description of the reservoir.As its core content,the 3D geological model of the reservoir can reflect the geological conditions and provide a reliable data body for the numerical simulation.Based on the existing geological knowledge and a large amount of geological data,the Yan 7 oil-bearing formation in the study area was studied on the 3D geological modeling of the reservoir.The model shows,(1)the Yan 72 sand body is continuously distributed in a large area in the northeast and southwest,the Yan 71 sand body is thicker in the northwest,northeast and east parts,and the mudstone interlayer is more common than the Yan 72.(2)The Yan 71 is identified as low porosity and medium permeability reservoir,and the Yan 72 low porosity and low permeability reservoir,and the degree of homogeneity of both is medium;the position of high value distribution range of Yan 71 is larger than that of Yan 72.It is well corresponding to the thicker sand body,which is a favorable reservoir in this area.After the consistency check of probability distribution and the verification of reserves calculation,the 3D geological model of the reservoir established on the target layer of Y33 block is reliable.It can accurately reflect the spatial distribution of the reservoir and the distribution characteristics of physical parameters,can be used as the original data body for subsequent numerical simulations,and can provide beneficial guidance for production and development.