基于平面与剖面相资料建立储层三维精细地质模型——以鄂尔多斯盆地S区块为例

The 3D Fine Geological Model Combining Plane and Profile Facies Data——Taking S Area in Ordos Basin as An Example

为精细表征鄂尔多斯盆地S区块不同沉积微相环境下储层砂体在平面及垂向上的展布规律,综合利用沉积平面相与单井剖面相资料,采用序贯指示模拟算法计算储层的三维精细相模型,再根据相模型控制采用高斯随机函数算法建立储层的属性参数模型,并对模型进行验证分析。结果表明:在相模型预测方面,工区平面上长8_2~1小层主要发育3条北东向展布的水下分流河道,东部主要发育泥质沉积;垂向上长8_2~1小层中部发育一套连片分布、稳定性好、厚度为15～30m的主力砂体,长81小层内部主要发育3套厚度为5～10m且平面上广泛发育的泥质隔夹层。在提高模型精度方面,变差函数主、次变程分析中步长取值150m可搜索到平面上任意井点的属性参数。抽稀井相模型验证可知相模型偏差率最大为6.5%,最小为0.0%,平均为3.0%,相模型精度高,为区块后期开发提供了可靠的数据基础。

In order to accurately characterize the distribution law of reservoir sand body of different sedimentary environment of S block of Ordos basin,single-well profile and areal sedimentary facies were comprehensive applied to establish the 3D fine facies model of reservoir by using sequential indicator simulation algorithm,then the attribute model was simulated under the control of the facies model by using gaussian random function,finally the geological model was evaluated.The results showed that:In the prediction of facies model,three north-east underwater distributary channel were developed in Chang-82^1 formation,the east of stratum was muddy sediment in the plane.In the profile,the main sand body with continuous distribution,good stability and thickness of 15~30 m were developed in the middle of Chang-82^1 formation,three sets of muddy interbed with thickness 5~10 m were widely developed in Chang-8 1 formation.In order to ensure the accuracy of the model,appropriate lag distance which is 150 m in variogram function setting of major and minor direction could search any well points parameters in the plane.It is proved that the maximum deviation rate of the facies model is 6.5%,the minimum is 0%,the average is 3% by using vacuate well pattern,the accuracy of facies model is high precision,the reliable data bases for the later oilfield development are provided.