As one of the main reservoirs types in the Sichuan Basin, the granular shoal reservoirs of the Feixianguan Formation have great potential for oil and gas exploration. Therefore, it is very important to study the sedimentary evolution characteristics and the distribution of shoal deposits of the Feixianguan Formation. In this paper, the sequence stratigraphy, sedimentary characteristics and distribution characteristics of the granular shoal deposits of the southwestern section of the Kaijiang–Liangping Trough in the Sichuan Basin were investigated, through core observations, thin section analysis, and field profiles measurement and sampling, combined with well-logging data and interpretations of two and three-dimensional seismic data of the local area. According to the identification marks, three sequence boundaries (SB1, SB2, and SB3) and two third-order sequences (SQ1 and SQ2) were identified, and a transgressive systems tract (TST) and highstand systems tract (HST) were distinguished in each third-order sequence. The analysis of the Feixianguan Formation sedimentary facies indicated that this formation developed in a carbonate platform setting. In the depositional period of SQ1, the study area inherited the sedimentary pattern of the Changxing Formation and developed carbonate platform depositions. During the SQ1-HST stage, the platform margin shoals and the intra-platform shoals in the study area were relatively well developed. During the SQ2-TST period, oolitic shoals were developed in the region, but their thicknesses were smaller than those of SQ1-HST. In addition, the distribution pattern of sedimentary facies was similar to that of SQ1-HST. The platform marginal zone was relatively narrow at that time, whereas the open platform was more widely distributed, and the distribution areas of platform margin shoals and intra-platform oolitic shoals were relatively limited. During the depositional period of SQ2-TST, the sea level dropped to the lowest level of the studied interval, and limited and evaporation platform facies developed in the study area. Based on previous studies, the influence of different factors on the deposition of the shoals in the Feixianguan Formation were evaluated. The results showed that under the influence of sea level, basement faults, and hydrodynamic conditions, the platform margin area in the study area was more favorable to the development of granular shoals, and the growth model of the granular shoals was “accretion before migration”.

飞仙关组颗粒浅滩储层是四川盆地的主要储层类型之一，具有很大的油气勘探潜力。因此，研究飞仙关组的沉积演化特征和浅滩沉积物的分布具有十分重要的意义。本文通过岩心观测，薄层分析和现场剖面测量与采样，研究了四川盆地开江—梁坪海槽西南段颗粒状浅滩沉积物的层序地层，沉积特征和分布特征，结合测井数据和对当地二维和三维地震数据的解释。根据识别标记，三个序列边界（SB1，SB2，和SB3）和两个三阶序列（SQ1和SQ2）被识别，并且在每个三阶序列中都区分了海侵系统域（TST）和高位系统域（HST）。对飞仙关组沉积相的分析表明，该组在碳酸盐台地环境中发育。在SQ1的沉积期，研究区继承了长兴组的沉积模式，并发育了碳酸盐台地沉积物。在SQ1-HST阶段，研究区的平台边缘浅滩和平台内浅滩相对较发达。在SQ2-TST时期，该地区发育了浅滩，但其厚度小于SQ1-HST。另外，沉积相的分布模式与SQ1-HST相似。当时平台边缘带相对较窄，而开放平台分布较广，平台边缘浅滩和平台内鲕粒浅滩的分布区域相对有限。在SQ2-TST沉积期间，海平面下降到研究区间的最低水平，研究区域内发育了有限的蒸发平台相。在以往研究的基础上，评价了不同因素对飞仙关组浅滩沉积的影响。结果表明，在海平面，基底断层和水动力条件的影响下，研究区平台边缘区更有利于颗粒浅滩的发育，颗粒浅滩的生长模型为“运移前增生”。 。