辫状河三角洲砂体较为发育,物性良好,可作为重要的油气储层。因此,深入分析其沉积特征、建立沉积模式及序列对油气勘探具有重要的指导作用。通过对准噶尔盆地南缘四工河剖面乌拉泊组辫状河三角洲露头进行实测,对各沉积微相沉积特征、岩相及粒度特征进行分析,最终建立该区辫状河三角洲沉积模式及垂向沉积序列。研究表明:四工河剖面沉积主要以辫状河三角洲平原和前缘亚相为主,微相主要为平原分流河道、分流河道间、水下分流河道及河口坝等,辫状河三角洲前缘砂质较为发育,以水下分流河道砂体为主,粒度较细,分选、磨圆均较好,可作为油气良好的储层;岩相识别、划分表明,乌拉泊组辫状河三角洲共发育8种典型的岩相类型,识别出4种典型的岩相及微相组合;辫状河分流河道粒度曲线主要由跳跃总体与悬浮总体组成,且水下分流河道跳跃总体可分为2段,河口坝粒度曲线由多段组成,较为复杂;在对沉积特征、岩相、粒度等研究的基础上,最终建立乌拉泊组辫状河三角洲沉积模式,可为区内油气勘探提供一定的指导。 Braided river delta sand body is more developed, good physical properties, can be used as an important oil and gas reservoirs. Therefore, in-depth analysis of its sedimentary characteristics, the establishment of sedimentary models and sequences of oil and gas exploration has an important guiding role. By measuring the outcrop of braided river delta in the Wulapo Formation of the Sijiang River profile on the southern margin of the Junggar Basin, the sedimentary microfacies sedimentary facies, lithofacies and granulometric characteristics are analyzed. Finally, the depositional pattern of the braided river delta and the vertical Deposition sequence. The results show that the sediments of the Sijiang River are dominated by braided river delta plain and frontier subfacies, and the microfacies are mainly plain distributary channel, distributary channel, underwater distributary channel and estuary dam. The braided river delta front The sand body is more developed, mainly submarine distributary channel sand body, with fine grain size, good sorting and rounding, which can be regarded as a good reservoir for oil and gas. Identification of lithofacies shows that the braided river delta of Wulapo Formation A total of eight typical lithofacies types were identified and four typical lithofacies and microseismic combinations were identified. The grain size curve of the braided river distributary channel was mainly composed of total leaping and total levitation, and the total number of underwater distributary channel leaps could be divided into 2 Based on the study of sedimentary characteristics, lithofacies and grain size, the sedimentary model of braided river delta in Wulapo Formation is finally established, which can provide some guidance for the exploration of oil and gas in the area. .