Productivity Evaluation Of Baobei Block In Baolang Oilfield

With the continuous improvement of oil and gas exploration and development,low-permeability oil and gas resources have become an important object of oil and gas exploration and development in China and even in the world.This paper takes Baolang Oilfield as the research object,and analyzes the effects of starting pressure gradient,stress sensitivity and rapid sensitivity on productivity.Combining experimental data,analytical model and numerical simulation to evaluate the production capacity,the main achievements and understandings are as follows:(1)Based on the laboratory core experiment,the seepage curve was drawn by single-phase oil seepage experiment.The curve was fitted by polynomial equation and exponential equation.The starting pressure gradient range of the experimental rock sample was calculated to be 0.000418?0.004059MPa/cm.The study shows that as the gas permeability of the core increases,the starting pressure gradient shows an exponential decline.(2)Stress sensitivity experiments show that the stress sensitive damage of experimental rock samples is weak.The core water sensitivity test shows that the water sensitivity of the rock sample is moderately weak.(3)Establish and derive a multi-factor productivity evaluation model based on experimental data.Taking the Baobei block as an example,the degree of influence of starting pressure gradient and stress sensitivity on productivity was studied.The results show that the effect of the starting pressure gradient on productivity is greater than the effect of stress sensitivity on capacity.It is recommended to fully consider the impact of the starting pressure gradient when making capacity predictions and developing a development plan.(4)By analyzing the PNN log data,it is found that the GR value of some wells after water injection is increased to some extent than that of the open hole.It is speculated that particle migration may occur in the formation.Then analyze the damage mechanism of particle migration and establish a physical model of particle migration to solve the critical flow velocity of particle migration.Calculate the damage radius of the particle migration according to the critical flow rate,establish a two-phase productivity equation considering the damage radius,and use this equation to calculate the production capacity of the production well and compare it with the actual production at the beginning of the water see.(5)The typical wells were selected for numerical simulation studies to further study the effects of starting pressure gradient and stress sensitivity on productivity in low permeability reservoirs.