【摘要】 东海海域西湖凹陷A区受限于海上平台开发模式，存在地层埋深大、钻井稀疏、地震资料分辨率低等瓶颈问题，传统测井与地震解释方法难以实现储层展布与内部结构的精细刻画。提出了少井条件下微古地貌约束的储层构型精细表征方法，精细刻画单砂体级次的储层构型分布。采用印模法并结合差异压实校正，精细恢复了研究区微古地貌；根据微古地貌与沉积耦合关系，结合-90°相位地震剖面与测井解释，刻画了辫流带的平面展布；依据辫流带及内部构型单元规模参数的经验公式、钻井平台附近局部相对密集的井网数据，估算辫流带心滩指数（横截面上心滩个数）、心滩规模与几何形态，完成平台附近的心滩精细刻画，以此为依据逐步外推，阐明了全区范围内心滩的分布规律。新钻水平井平均砂体吻合率89.6%，辫状河道与心滩的吻合率均超过87%，预测的辫流带与实钻数据高度吻合，同时，辫流带内部心滩分布规律对井轨迹调整具有指导意义。该方法可为钻井较少的海上油田中—深部储层预测提供借鉴。更多还原

【Abstract】 In Area A of the Xihu Sag in the East China Sea, offshore platform development is constrained by challenges such as deep burial of strata, sparse drilling, and low seismic resolution. These limitations hinder the precise characterization of reservoir distribution and internal structures using conventional welllogging and seismic interpretation methods. Therefore, this study proposed an innovative characterization method for fine-scale reservoir architecture with limited wells, which was constrained by micropaleogeomorphology, to delineate single sand body architectures in detail. First, the study employed the impression method combined with differential compaction correction to refine the reconstruction of micro-paleogeomorphology in the study area. Then, based on the coupling relationship between micro-paleogeomorphology and sedimentation, the braided zone’s planar distribution was characterized using-90° phase seismic profiles and well-log interpretation. Subsequently, using empirical formulas for the scale parameters of braided zones and internal architectural elements, along with relatively dense well data near drilling platforms, the study estimated the mid-channel bar index(number of mid-channel bars in cross-sections) and the scale and geometry of mid-channel bars, enabling their detailed characterization near platforms. This characterization was then gradually extrapolated to clarify the distribution pattern of mid-channel bars across the entire study area. The newly drilled horizontal wells exhibit an average sand-body matching rate of 89. 6%, with matching rates for braided channels and mid-channel bars both exceeding 87%. The predicted braided zones show a high degree of consistency with the actual drilling results. Moreover, the distribution patterns of mid-channel bars within the braided zones provide effective guidance for optimizing well trajectory design. This method provides valuable insights for offshore oil fields with limited drilling data, particularly for predicting medium-to deep-buried reservoirs.更多还原