Using the strong field approximation method combined with the time window function, the two-dimensional (2D) momentum spectra of hydrogen atoms for above-threshold ionization by a few-cycle intense laser field were calculated and compared with the results obtained by the Coulomb-Volkov approximation combined with the time window function. It is found that the fanlike structures in the 2D momentum spectra are formed as a result of the interplay of intracycle and intercycle interferences under the action of a long-range Coulomb potential. In addition, the 2D momentum spectra of hydrogen atoms under different pulse durations were calculated by solving the time-dependent Schr dinger equation and it is found that some special fringe structures appear in the 2D momentum spectra beyond the intracycle and intercycle interference fringes. These structures are formed by the rescattered electron wave packets.