A three-dimensional precise geological model of ultra-deep carbonate fault-controlled reservoirs based on multi-level simulation

The ultra-deep fault-controlled reservoirs in the SB area of the Tarim Basin exhibit overall oil-bearing characteristics along fault surfaces with significant local differential enrichment. As the dominant reservoir type, these reservoirs demonstrate diverse stratigraphic sequences, irregular morphology, and strong heterogeneity. The limited understanding of the heterogeneity evolution mechanism and production dynamics in fault-controlled reservoirs has significantly constrained the efficient development of hydrocarbon resources. While seismic attribute analysis and inversion technologies are widely applied in reservoir characterization, their resolution remains insufficient for multi-scale heterogeneity characterization in ultra-deep fault-controlled reservoirs (> 8000 m), particularly in accurately reconstructing three-dimensional coupling relationships among fault geometries, dissolution cavities, and fracture networks. This study focuses on two typical fault-controlled reservoir units in the SB area, integrating seismic data, attribute characteristics, and inversion parameters to establish a "layered refinement-equivalent fusion" numerical reservoir modeling approach. The constructed multi-scale three-dimensional geological model systematically reveals three-dimensional spatial configuration patterns of fault structures, microfracture networks, and pore-cavity systems within reservoirs. Research results demonstrate that reservoir units can be classified into fault surfaces, cavernous bodies, and fracture-pore matrices. The cavernous reservoirs exhibit clustered distribution patterns, vertically connected through microfractures to form a networked transport system, collectively demonstrating a "multi-compartment, multi-cluster" spatial configuration. Multiple longitudinal high-permeability zones within cavernous bodies interconnect laterally through microfractures, forming an integrated network transport structure. Furthermore, this study identifies evolutionary patterns of high-permeability zones in cavernous structures under tectonic stress and develops 12 geological models encompassing 2 fault geometry types, 2 petrophysical distribution patterns, and 3 cavity-filling styles. The proposed modeling methodology effectively overcomes technical challenges in multi-scale collaborative modeling spanning millimeter-scale microfracture systems to kilometer-scale macro-fracture systems, significantly enhancing characterization accuracy of spatial distribution patterns and heterogeneous attributes in reservoir units. This breakthrough provides critical theoretical and technical support for efficient development of deep complex fault-controlled reservoirs. • Combined seismic facies, deep learning, and imaging logging with DFN modeling for 3D microfracture characterization. • Established stratification-controlled reservoir models revealing multi-grid multi-cluster configurations through 12 integrated 3D frameworks. • Integrated seismic-logging-core datasets into clustered permeability models enabling zonal heterogeneity analysis for development optimization.