准噶尔盆地腹部侏罗系砂体成因类型与储集性能

准噶尔盆地腹部侏罗系沉积砂体成因类型多样,其中三角洲前缘亚相中的水下分流河道砂体是主要的储集体.不同的成因砂体其叠置关系不同,三工河组二二段(J1s2^2)砂体为拼合板式结构,其他层系砂体结构类型主要为迷宫武结构;各成因砂体对砂岩物性的控制作用主要体现在砂岩的粒级上,粗粒径砂体其物性往往较好,但在不同深度上其控制的影响程度有差异,中浅层河口坝和水下分流河道砂体物性均较优,中深层水下分流河道物性优于河口坝砂体,超深层成因砂体之间物性差异变小.

On Genetic Type and Reservoir Quality of Jurassic Sands in Hinterland of Junggar Basin

There exist many types of genetic sandbodies of Jurassic in hinterland of Junggar basin, in which submerged distributary channel sandbody in delta front subfacies is the major reservoir. The different kinds of genetic sandbody show the different superimposed structures. The sandbody of J1S22 is of split planar texture, while the rest sequence sandbodies are dominated by labyrinth-like ones. The size grade of each genetic sandbody mainly controls the sandstone physical properties. The coarse-grained sandbody shows better property, depending on the depth. The petrophysical property of channel mouth bar in moderate-shallow depth are good as that of submerged distributary channel sandbody; however, that of submerged distributary channel sandbody in deep-intermediate depth is better than that of the mouth bar sandbody; and that of super-deep sandbody shows little variation.