Research on Modeling of Fault-controlled Reservoirs in the 4th Condensate Gas Reservoir of SHB Oilfield

The reservoir of the SHB oilfield is faultcontrolled and constitutes a fault-controlled carbonate reservoir. The distribution of the reservoir is affected by the fault system, cave combination, and variations in cavity filling materials, which significantly influences oil and gas accumulation and development. Challenges such as deep burial depth, low seismic resolution, and complex logging interpretation make the fine delineation and modeling of the fault-controlled reservoir more demanding compared to traditional layer-controlled carbonate reservoirs. Therefore, the utilization of 3D seismic attributes for accurately delineating the distribution of faults and cavities becomes particularly crucial. This study centers on the SHB43X block as a typical unit of a fault-controlled reservoir. The spatial structural characteristics of the reservoir’s fault-controlled units within this block are analyzed based on seismic data, seismic attributes, and inversion data. Subsequently, a refined layer-by-layer reservoir model is established through multilevel unit equivalent fusion to construct a geological model of the fault-controlled body. Based on the pattern division under different stress backgrounds, the scale of the reservoir, the angular breccia belt, the fracture belt, and the chaotic body are determined to establish a framework model of the fault surface. For reservoir development within the fault surface along the principal stress direction, it is influenced by strike-slip fault belts. Small faults pass through dissolution to form a series of longitudinal angular breccia belts, which are more developed at cave contact positions. A grid cluster model of the fault surface is established. Guided by reservoir development pattern maps in different stress sections, a hierarchical modeling approach is adopted to gradually create cross-sectional models. The detailed description of fault-controlled reservoirs will enhance the understanding of non-uniformity and its control within faulted body units and production dynamics of oil reservoirs. This will assist in the efficient development of oil and gas resources in faulted body units and provide technical support for similar oil and gas reservoir development in SHB.