基于岩相约束的致密砂岩储层分类评价OACSTPCD

Aiming at the issues of poor physical properties,complex microscopic pore structure and heterogeneity of tight sandstone res-ervoirs in the east Ⅱ area of Sulige gasfield,the reservoir characteristics of the study area are studied based on lithofacies,and the reser-voirs are comprehensively classified and evaluated in combination with macroscopic structure and microscopic characteristics.The re-sults show that there are six lithofacies types in the lower submember of He 8 member in the study area,that is,block bedding conglom-erate facies,block bedding medium coarse sandstone facies,cross-bedding medium coarse sandstone facies,parallel bedding fine sand-stone facies,wavy bedding/block bedding silty fine sandstone facies and horizontal bedding/block bedding mudstone facies.Among them,the physical properties,pore throat size and connectivity of the cross-bedding medium coarse sandstone facies and the block bed-ding medium coarse sandstone facies are relatively good,and their heterogeneity is weak.The comprehensive classification evaluation criteria of the reservoirs are established based on the characterization parameters of lithofacies,pore structure and their heterogeneity,and the reservoirs in the target layer are divided into five types.Based on the classification evaluation results of single well reservoirs,four reservoir development modes are summarized,including progressively varying type,thick layer alternating type,thin layer frequent alternating type and thick-thin layer alternating type.