英东一号构造储层特征及采收率分析

Reservoir characteristic and recovery efficiency analysis of No.1 Yingdong structure

针对英东一号构造储层开展大量的室内实验,利用最新钻井岩心开展岩心粒度、压汞、薄片鉴定、X衍射、等方法对英东一号构造主力油层油砂山组储层岩性、物性、孔隙结构特征进行了分析,结果表明该区储层黏土含量高、水敏矿物发育、储层岩石胶结以孔隙胶结为主、分选性好、孔隙以原生粒间孔为主、储层属中高孔、中渗砂岩储层。室内岩心润湿性和驱油效率实验分析表明,英东油田油砂山组油藏为强亲水油藏,有利于水驱开发。从注气提高采收率效果进行了评价分析。英东地区由于储层跨度大,油气交错分布,气源充足,气油比高,因此注气具有很大优势。水驱后气水交替能一定程度上防止干气较快突破,对中高渗组和低渗组岩心水驱后气水交替比直接干气驱采收率分别提高了23%和10%.明确油田储层微观孔隙结构特征、明确注气提高采收率的方法对英东油田今后开发方案的制定有重要意义。

According to No. 1 Yingdong Structure, to carry out a large number of indoor experiments. U sing the latest drilling cores for granularity, mercury injection, thin section identification, Xray diffrac tion, etc, this paper analyzes Youshashan formation which are major reservoirs in No. 1 Yingdong Struc ture by core observation, thin section authentication, rock intrusive and physical property analysis. The result show that high clay and development of water sensitivity minerals, pore cementation is major rock cementation with good sorting and primary porosity is major pore in this reservoir. In this area, reservoir has mediumhigh porosity and medium permeability sandstone. Rock wettability and interior oil dis placement efficiency experiment show that Youshashan formation which are major reservoirs in No. 1 Yingdong Structure is strong water wet reservoir, in favor of water flooding development because reservoir has long span. Based on the analysis of oil recovery by gas injection effect is evaluated, oil and gas stag gered distribution, gas source is enough, gas oil ratio is high, so gas injection has better advantage. Af ter water drive, gas alternating water could prevent dry gas disappear rapidly in some way. After core water drive of low permeability formation and high permeability formation, recovery efficiency of gas al ternating water had raised 23% and 10% respectively and it is higher than dry gas drive.