牛心坨油田牛心坨油层储集条件研究

Reservoir Conditions in Niuxintuo Reservoir of Niuxintuo Oilfield

辽河盆地牛心坨油田牛心坨油层属扇三角洲湖相 (湾 )沉积 ,其沉积环境的差异导致砂岩储层存在较严重的非均质性。岩心描述和常规薄片、铸体薄片、扫描电镜、粘土矿物 X-衍射分析及压汞资料研究表明 ,牛心坨油层的岩石类型主要为岩屑长石砂岩 ;砂岩储层以前扇三角洲的远砂坝、扇三角洲前缘的砂质分流河道砂、砾砂质分流河道砂及河口坝砂的物性最好 ,席状砂、滩坝砂和前缘砾质分流河道砂、前缘砂次之 ,扇三角洲平原的砾质水道砂、砾砂质水道砂、砂质水道砂物性最差 ;储层孔喉分布状况差、结构复杂、喉道细小且不均匀是该套储层的突出特点 ;成岩作用是影响储层微观非均质性的重要因素。

Niuxintuo reservoir of Niuxintuo oilfield in Liaohe basin is a fan delta lake facies sedimentary system, where the difference of sedimentary environment results in serious heterogeneity of the sandstone reservoirs Core descriptions, conventional thin section, cast thin sections, SEM observations, X ray analysis of clay minerals and mercury penetration data show that the major rock type of the Niuxintuo reservoir is a lithic arkose Also, it is found that, in the sandstone,an outer bar sandbodies in the sandy distributary channel,conglomeratic sandy distributary channel and sandbar of the delta front is the best in physical properties; sandsheet,sandbodies from conglomeratic sandy distributary channel and front sandbodies—better;and sandbodies in the conglomeratic distributary channel, conglomeratic sandy distributary channel and sand distributary channel of delta plain—the worst The reservoir is poor in pore throat distribution, complex in structure, small in throat and their evident characters are heterogeneous A diagenesis is the key factor affecting the microheterogeneity of the reservoir