非构造成藏的储集与封堵条件

松辽盆地南部非构造圈闭中的储集体大都由各体系域中不同类型砂体构成,主要有低水位体系域中的湖底扇砂体、前积楔状砂体;湖盆扩张体系域中的扇三角洲砂体、水进砂体及河道砂体;高水位体系域中的三角洲前缘砂体、趾部浊积砂体及扇三角洲砂体。这些砂体中除个别外,大部分规模较小、分布局限。虽然这些砂体往往无须构造条件配合就能形成圈闭,但对封堵条件要求较高。根据封堵的层位以及与层序界面的关系大体可将非构造圈闭的封堵型式划分为E-S-H-H型、E-E-S-H型、E-L-S-H型、E-S-B型、E-L-L型、E-E-E型和H-H-H型等7种。其中以E-E-E型、H-H-H型和E-L-S-H型最好,为一类封堵。

RESERVOIRING AND SEALING CONDITIONS OF NON STURCTURE POOLS

Reservoir rocks of non sturcture traps in southern part of Songliao Basin consist of different types of sandbodies in LST,EST and HST such as basin floor fans and progressive wedges in Lower Stand System Tracts(LST),transgressive sands and river channel sandbodies in Expanding System Tracts(EST),delta front,fan delta and fan toe turbidite in High Stand System Tracts(HST).Most of the sands are not large in size and their destribution is limited.These sandbodies can form oil and gas traps without the matching of structural condition,but require high sealing condilion.According to the relatiorship between sealing positions and sequence boundaries,seeling conditions of non structrure formed reservoirs can be classified into 7 types:E S H H,E E S H,E L S H,E S B,E L L,E E E and H H H.Among them,E E E,H H H and E L S H are the most favourite sealling conditions.