Successful exploitation of the fractured-vuggy carbonate reservoirs (FVCR) requires establishing long-term connectivity between the wellbore and vugs where hydrocarbon is stored. Acid fracturing is a common practice to create passageways for such reservoirs. However, the fracture propagation behavior is complex due to the interaction among hydraulic fractures (HFs), natural fractures (NFs), and vugs. Yet, a comprehensive investigation accounting for the geological genesis of FVCRs, fracture propagation behavior analysis, and exploitation strategies has not been conducted so far. To this end, taking the Shunbei oil field, Tarim Basin, China, as an example, this study using the RFPA (Realistic Failure Process Analysis) simulator classifies the possible NF distribution patterns in the Shunbei oil field through forward modeling in the first place. Then, the interaction mechanism among HFs, NFs, and vugs is analyzed from the perspective of damage mechanics. The results indicate that the vugs can be connected either hydraulically or mechanically. Finally, the field scale fracture propagation simulations are performed to examine the effect of engineering parameters and geological properties on the stimulation effectiveness. The exploitation strategies for different geological conditions are proposed based on the field scale simulation.
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