HE Faqi, LI Junlu, GAO Yilong, et al. Development characteristics and potential of fault-fracture reservoir in southwest margin of Ordos Basin[J]. Petroleum Reservoir Evaluation and Development, 2024, 14(5): 667-677.
DOI:
HE Faqi, LI Junlu, GAO Yilong, et al. Development characteristics and potential of fault-fracture reservoir in southwest margin of Ordos Basin[J]. Petroleum Reservoir Evaluation and Development, 2024, 14(5): 667-677. DOI: 10.13809/j.cnki.cn32-1825/te.2024.05.001.
Development characteristics and potential of fault-fracture reservoir in southwest margin of Ordos Basin
The southwest margin of Ordos Basin has developed faults and fractures to varying scales
significantly enhancing the permeability of tight reservoirs and forming high-quality fault-fracture reservoirs against a backdrop of low permeability reservoir types. However
this also complicates the reservoir's homogeneity and the variability of its capacity
posing challenges for fine characterization of the reservoir's internal structure and for researching capacity control factors. To address these issues
the study employs spatial characterization of the fracture system
fracture classification
and capacity comparative analysis. Further
the development characteristics of the fault-fracture reservoir are defined through joint well-seismic and reservoir research. Key findings from this research include: 1) Establishment of the “binary four zones” model for fault-fracture reservoirs
which divides the reservoir into four distinct zones: the core fracture zone
the induced fracture zone
the micro-fracture transformation zone
and the matrix pore zone. Among these
the core fracture zone is identified as the primary contributor to production yield. 2) It is observed that the longer the fault extension length and the higher the solid drilling structure position
the higher the single well production capacity in the core fracture zone. The induced fracture zone's proximity to the fault correlates with higher production capacity
demonstrating the spatial impact of fault structures on reservoir productivity. 3) The production characteristics of fracture wells are categorized into three stages: ① the fracture system acts as the high yield stage; ② the fracture system serves as the storage stage and plays the role of diversion; ③ the fracture's primarily function in diversion. This research significantly increases the proportion of high-yield wells in the fault-fracture reservoir
providing crucial insights for guiding efficient
ongoing exploration and development activities in the Mesozoic reservoirs on the southwest margin of the basin. This strategic approach enhances understanding and management of fault-fracture reservoirs
optimizing resource extraction and improving operational efficiencies.