海塔盆地优质储层发育特征及控制因素分析

凝灰质砂岩是海塔盆地主要油气储集岩层,凝灰质含量随地层变老而增多,储层物性非均质性强,大量薄片等储层微观分析结果表明,凝灰质砂岩成分和结构成熟度较低,储层储集空间主要为溶蚀成因的次生孔隙,且次生孔隙比例随地层变老而增加.本文提出孔隙成因法,并根据该方法确定凝灰质砂岩优质储层物性下限的孔隙度为10％,渗透率为0.1×10...

Development character and dominant factor of high-quality reservoir in Hailar-Tamtsag Basin

Tuffaceous sandstone is the main hydrocarbon reservoir rocks in the Hailar Tamtsag Basin，tuffaceous content increased with strata to be older，and the reservoir has higher heterogeneity.By micro analysis of many thin sections，the study shows that the reservoirs compositional maturity and texture maturity is lower，and the main reservoir space is secondary vugularsolution porosity.The proportion of secondary porosity increased with strata to be older.In this paper，the method of porosity genesis is proposed and the lower limit of high quality reservoir is identified，porosity of tuffaceous sandstone is 10％，permeability is 0.1×10-3μm2，the proportion of secondary porosity is 30％.Delta front subfacies is the formation foundation of tuffaceous sandstone.Disslution of organic acids and leaching of meteoric water are the formation of the main factors of high quality reservoir.