黄骅坳陷王官屯油田官104断块古近系孔店组辫状河储层流动单元

FLOW UNITS OF BRAIDED RIVER RESERVOIRS OF THE KONGDIAN FORMATION OF PALEOGENE IN FAULTED BLOCK GUAN 104 OF WANGGUANTUN OILFIELD, HUANGHUA DEPRESSION

以黄骅坳陷王官屯油田官104断块为例,探讨辫状河储层流动单元的研究方法。储层流动单元研究包括两个层次,其一为渗流屏障和连通体分析,其二为渗流差异分析。研究区主要微相类型有心滩、辫状河道与河道间。渗流屏障主要为泥岩屏障和成岩胶结屏障。通过渗流差异分析将官104断块枣Ⅲ和枣Ⅱ油组辫状河储层划分为四类流动单元。其中,Ⅰ类流动单元以中高孔、中高渗为主要特征,主要分布于心滩与辫状河道主体部位;Ⅱ类流动单元属中孔、中低渗储层,主要分布于辫状河道;Ⅲ类流动单元以中低孔、低渗透率为主要特征,分布于河道侧缘及河漫滩微相;Ⅳ类储层流动单元主要为渗透性极差的非储集层。通过综合分析,建立了工区储层流动单元的分布模型。这一研究对于优化油田开发调整方案具有重要的指导意义。

Taking the Faulted Block Guan 104 of Wangguantun Oilfield in Huanghua Depression, Bohai Bay Basin as an example,this paper deals with flow units study of braided river reservoir. The step of research includes two folds. The first is the analysis of seepage barrier and connected sandbody, and the second is the analysis of seepage variation. The main microfacies are midchannel bar,braided channel and overbank. The types of seepage barriers include shale and cemented belts. Through seepage variation analysis, four kinds of flow units were classified in the braided river reservoir of Zao Ⅰ and Zao Ⅱoil-containing intervals in Faulted Block Guan 104. Flow unit I is characterized by medium-high porosity and permeability reservoir, mainly distributed in mid-channel bar and the core of braided channels. Flow unit Ⅱ is characterized by medium porosity and medium to low permeability reservoir,mainly distributed in braided channels. Flow unit Ⅲ is characterized by medium to low porosity and low permeability reservoir,mainly distributed in the margin of channels and overbank. Flow unit Ⅳ is in fact non-reservoir with extremely low permeability. Lastly the distribution model of flow units of the study area was made through the analysis of seepage barrier and seepage variation. The study is very important to optimize the oilfield development adjustment plan.