苏里格气田盒8段辫状河储集层构型空间展布

Spatial Distribution of Architectures of Braided River Reservoirs in He 8 Member,Sulige Gas Field

为确定苏里格气田盒8段多期叠置辫状河致密砂岩储集层构型和空间展布,利用测井和岩心资料,参照现代河流,确定了研究区辫状河储集层的构型划分方案,分级次精细解剖了储集层构型单元;利用基于象元法和基于目标法联合模拟,建立了包含多级构型单元的辫状河储集层构型三维模型,精细刻画了不同类型储集层构型的空间展布。研究区盒8段储集层为多期辫状河道砂体垂向和侧向切割叠置形成,单一辫流带内心滩呈透镜状,内部被不连续的落淤层分隔,辫流水道环绕心滩分布。依据三维模型,储集层可分为不同级次构型体,其中有利储集层为盒84小层,主要分布在研究区东部和西部南北向展布的两大辫流带内,优质砂体在辫流带内部呈透镜状分布。研究结果应用于水平井部署和地质导向,钻探结果与模型预测符合率高。

In order to determine the spatial distribution of the architectures of the multi⁃stage superimposed braided⁃river tight sandstone reservoirs in the He 8 member,Sulige gas field,by using well logging and core data and referring to modern rivers,the architecture division scheme of the braided river reservoirs in the study area was determined,and the reservoir architecture units were dissected hierarchically.Through the joint simulation based on pixel and target methods,a 3D architecture model of the braided river reservoir including multi⁃level architecture units was established to finely depict the spatial distribution of different reservoir architectures.The reservoirs in the He 8 member formed due to the vertical or lateral cutting and stacking of multi⁃phase sand bodies of braided channel.The mid⁃channel bar of a single braided belt appears in form of lens.The interior of mid⁃channel bar is separated by discontinuous fall⁃siltseam,and the braided channels are distributed around the mid⁃channel bar.According to the 3D architecture model,the reservoir can be divided into different hi⁃erarchical architectures,among which the favorable reservoir interval is He 84 sublayer which is mainly distributed in two major braided belts extending north⁃south in the east and west of the study area,and high⁃quality sand bodies are distributed in a lenticular shape inside the braided belt.The research results were applied to horizontal well deployment and geosteering drilling,and the drilling results show a high coincidence rate with model predictions.