Formation of invaded zone during drilling with water- and oil-based mud
Numerical simulation of hydrodynamic processes in oil-saturated reservoir during vertical well drilling was done. Effect of drilling technique and type of drilling mud (water- and oil-based) was investigated. Processes of oil-based mud-filtrate invasion were simulated by three-phase filtration. Effects of hydrodynamic parameters of invaded zone on borehole resistivity measurements were investigated. Determination of parameters and structure of invaded zone under interpretation of electromagnetic loggings reduces uncertainty of constructed geoelectric and hydrodynamic models of reservoirs with different saturating fluid.