Driving Force Analysis and Development Adjustment Solutions for Reservoirs with Low Relief and Strong Natural EnergyWater Flooding

摘要

T Block in Ecuador has been in the late development stages which encountered the difficulty of controlling water cut and stabilizing oil production after nearly 40 years’ development due to the low relief, active edge bottom water and weak heterogeneity characteristic. Based on the analysis of main driving forces, the paper extracted the characteristic parameters, established typical numerical models to analyze the remaining oil distribution pattern and main control factors, finally put forward the comprehensive adjustment solutions. The research shows that due to the influence of weak heterogeneity and high vertical permeability, the remaining oil tends to distribute on the top of the reservoir because of gravity segregation. And the pay zone thickness and displacement speed are the main factors for remaining oil development effect. Based on the above analysis, the effect of remaining oil production of horizontal wells and vertical wells was compared and demonstrated that horizontal wells have much more advantages over vertical wells in remaining oil development. The study optimized the horizontal well production parameters and put forward the oil field comprehensive adjustment solutions. The proposed horizontal wells in T block achieved 36 days’ water-free oil production period and the initial oil rate is 528.20 m3/day which proved the soundness and efficiency of our method. This paper can provide a theoretic guidance for the development of similar oil fields.