Abstract: It’s difficult to deal with the heterogeneous anisotropic geological conditions in TOUGH2 simulator， therefore，a new algorithm， using anisotropic permeability tensor， was coupled in TOUGH2 simulator. And the direction of rock’s hydraulic conductivity and elements connection parameters for anisotropic medium was added in the TOUGH2’s input file， which can solve the problems of the anisotropic permeability in different regions and the disparity between the main direction of permeability and the axis direction. Through the simulation of the anisotropic media’s influence on the spatial distribution of CO2 gas saturation， it can be found that CO2 migrates faster and further in the principal direction than the other directions， thereby the effectiveness of the algorithm is proved. The study effectively enhances the function of the TOUGH2’s simulator， which can deal with the seepage problems of complex geological conditions and make the simulation result more objective and practical.

Key words: TOUGH2, fluid migration, anisotropy, numerical simulation, permeability