Quantitative Prediction Of Reservoir Fracture Of Funing Group In Bian-Min-Yang Region

On the basis of core fracture description, hydraulic cracking calculation and sound speed experiment, the relationship between crustal stress and parameters of tectonic fracture was confirmed using mathematics, mechanics and geology method. This dissertation analyzed the distribution of crustal stress and tectonic fracture of Funing Group in Biandong, Minqiao and Yangjiaba region.42 wells core fracture statistics shows that Funing Group of BMY mainly developed high angle fractures and vertical fractures with trend of nearly WE and NEE, NWW. Macrofractures mainly distributed in 0.2-0.6mm. The fracture linear density is small and changed greatly interwell. Most of the tectonic fractures were wholly filled with calcite and the rest of them were filled with asphalt and slime. Tectonic fractures appear in several forms such as tension fracture, shear fracture and tension-shear fracture. The structural evolution analysis shows the Late Funing Period is the important fracture period.The quantitative relationship between crustal stress and parameters of tectonic fracture is the key to the reservoir fracture prediction. On the basis of strain energy, surface energy in rock and fracturing mechanics theory, the relationship was confirmed using the represent element volume and flat seepage model. The Coulomb-Mohr principle was applied to the examination of shear fracture, while Griffith principle was taken as the examination of tension fracture.Diplog and structure map were used to core orientation. Penetrating fluid method and sound speed experiment were used to confirm the value and orientation of the current crustal stress. The stress distribution of BMY area was confirmed by ancient and current stress field numerical simulation. The comparison between simulation and hydraulic cracking data shows that crustal stress numerical simulation is accurate. The high position of BMY area is the current crustal stress low-value area. The relationship between crustal stress and formation depth is linear. Faults for the control of stress have a significant role. Stress concentration occurred near the fault zone in the paleo stress field while the current stress distribution reverse. Biandong, Minqiao and Yangjiaba have the unified direction of stress. The minimum principal stress is nearly north-south. The crustal stress simulation data were imported to fracture parameters model, and the predicted parameters were verified by the core fracture statistical data. The result shows that, the central area of Biandong, m35 block of south Minqiao and the south fault upcast of Yangjiaba were the intensive fracture areas in which the fracture porosity and permeability are highest. Tectonic fractures of BMY area have the following characteristics: The high value areas of tensile stress in the paleo-stress field are the fracture-intensive areas; Fractures in high part have greater aperture and better poroperm characteristics; The dominant fracture strike decides the current east-west and vertical component of permeability are significantly higher than the north-south component.