▎ 摘　　要

Epitaxial graphene supported by transition metals with an interface lattice mismatch exhibits moire superstructures. Though investigations at the atomic scale have been extensively performed, to date most of them focus on substrates with the same symmetry of graphene. Herein, we discuss the general formation mechanisms of graphene moire structures on square lattice supports from a geometric perspective. The analytic forms describing the moire orientation, periodicity, and unit cell size of isotropically strained graphene have been derived using a crossing-stripe construction, yielding results in noticeable accordance with the experimental findings reported in the literature. Besides, we exploit a model assuming an anisotropic deformation of graphene lattice to more accurately describe the atomic configuration of any moire pattern. The discrete occurrence of graphene misorientation angles is also discussed by taking into account the energetics of the system; a general tensile strain favoring an isotropic deformation is discovered.