Hydraulic fracturing technology is one of the most popular and efficient reservoir stimulation techniques in oil and gas industry since it allows significant increase of the hydrocarbon production rate. A possible advancement of this technology involves consequent pumping of several immiscible fluids laden with solid particles (proppant) into a fracture. This technique has a potential for better control of the proppant placement and, thus, a better control of the fracture shape. The major result of the present work is a mathematical model and a computational code for investigation of a flow of two immiscible slurries inside an expanding fracture. (C) 2012 Canadian Society for Chemical Engineering