Study On Fracturing Parameters Optimization Design Of Bei 14 Block In Hailaer Oilfield

At present,fracturing is the main measure for high production and stable production in Hailar Oilfield,and multiple fracturing of old wells will be the main measures for stable production in the future.Since most of the wells in this block have been subjected to fracturing,along with long-term injection and production,the ground stress of the block has been greatly different from the original ground stress,which has created great difficulties for the follow-up fracturing design.Therefore,the distribution of the current stress field in this block is revealed,and the direction of crack extension of the new fractured well is obtained.Combined with the optimization of fracture parameters in fractured wells,higher recovery factors can be achieved.Ground stress is the key factor in determining the position and orientation of hydraulic fracture initiation.The dynamic changes of fracturing process and injection and production will induce the deflection of the stress field,which may cause the rear fracturing fractures to turn.In order to better predict the extension direction of the fracturing fractures,the magnitude and direction of the original geostress of the Bei 14 block in Hailaer were tested by indoor viscous remanence,anisotropy of wave velocity,acoustic emission and differential strain experiments.The triaxial stress test was used to test the rock mechanics parameters of the block.Then,the three-dimensional geological model of the Bei 14 block is built by using finite element numerical simulation software.A three-dimensional model of the ground stress field based on the coupling of stress field and seepage field is established based on the experimental results of rock mechanics parameters.According to the distribution of the original ground stress,the inversion model of the ground stress is established.Since the block uses multiple layers of fracturing,a fracture pressure inversion method based on the fracturing construction curve is established to analyze the sensitivity of the fracture pressure,and the fracture layer location of the synthetic fracturing fracture is determined by combining the physical properties of each small layer.From the analysis results,it can be seen that the small layer with high porosity has a low rupture pressure and is prone to fractures.Many wells in the study area have undergone multiple fracturing,and the knowledge of the stress field before each fracturing of each well is the basis for studying the trend and shape of fractures.According to the original geostress direction simulated by the three-dimensional geological model and the fracturing time sequence around the well pattern,the distribution law of fracturing fractures around the well pattern in this area was obtained,and the distribution characteristics of fractures in each small layer were obtained.Through numerical simulation,the in-situ stress field distribution of each small layer in the Block 14 is determined.Based on the daily oil production and cumulative oil production,the influence of formation permeability,fracturing fracture length,and conductivity on productivity was analyzed.The optimal fracture length and diversion capacity for different formation permeability in bei 14 block of Hailarbei are obtained.Through the simulation of the remaining oil distribution after20 years,we can see that this optimized scheme has a good recovery rate,which has a very good guiding significance for the new well fracturing and the repeated fracturing of old wells in bei 14 block of Hailarbei.