Abstract: Current schemes of removing near-surface effects on seismic data processing are mainly static corrections or wave-equation datuming (WED).In the presence of rough topography or strong lateral velocity variations in the near surface，the WED scheme is the only option available.However，the traditional procedure of WED requires to downward continue the sources and receivers in different domains，respectively.So the author has presented a new datuming method based on global wavefield continuation (WEDD).In this paper，the WEDD are compared with the traditional datuming methods firstly in theory，and then their advantages，disadvantages and the applicable scope are discussed.

Key words: single domain, wave-equation, datuming, double square root operator, static corrections