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The three dimensional(3D)enhanced extended finite element method(EXFEM)is developed to model the hydraulic fracture in heterogeneous and layered rocks.The positions of fracture surface and front are explicitly tracked and the fluid pressure can be applied on the fracture surface by introducing the level set function in the fracture element.At the same time,the average stress field at fracture front can be effectively evaluated and used to decide the fracture propagation direction.Another side,by integrated with cohesive zone method,EXFEM can conveniently model the discontinuity zone like contact,joint and fault in the rocks.To show the applicability and accuracy of EXFEM,the fracture branching,multi-fracture and fracture propagation in the layered stratum are simulated.The hydraulic fracture can propagate,deflect,arrest or penetrate the discontinuity zone in the simulations.The dependence of fracture path on the layer interface properties is studied.