储层泥浆侵入深度预测方法研究

泥浆侵入半径的确定尚缺乏严格的验证标准.以油水两相渗流理论和离子扩散方程为基础,结合储集层特点,研究了不同储层参数下泥浆滤液对地层的侵入特性.数值模拟侵入时间选取10 d和20 d.数值模拟结果表明,侵入半径在渗透率不变的情况下随孔隙度的增大而减小,在孔隙度不变的情况下随渗透率的增大而增大;当渗透率和孔隙度都发生变化时,泥浆侵入半径一般随孔隙度的增加呈幂函数增加.依据这种关系对测井资料约束处理,得到的泥浆侵入半径较客观地反映了地层的真实情况.

Research of Mud Invasion Depth Prediction Method in Reservoir

The determination of exact invasion radius of mud is prerequisite to correct the electric log data of low resistivity hydrocarbon reservoir. However, the rigorous verification criterion is deficient in ascertaining invasion radius of mud. On the basis of the oil-water two-phase flow theory and the ion diffusion equation, studied is the formation invasion characteristic of mud filtrate with different reservoir properties. In numerical simulation, the given mud invasion time is 10 days and 20 days. The simulation result shows that the radius decreases with the increase of porosity when permeability does not ses. According to the relationship mentioned above, the mud invasion radius obtained from electric log data processing may comparatively reflect the true formation.