Abstract: In this paper,a new solution to the near-surface problem-the datum correcting method based on the global wavefield continuation is presented.According to the mutual exchange principle of the earthquake theory and the observed surface settlement concept,the treatment of shotpoint and geophone station will be combined during the datum correcting process.The global continuation of the single wavefield will be achieved by the double square root operator in shotpoint-offset domain.At last,the wavefield vale of the target depth is extracted and the reference surface is redefined.The trial calculated results show that the datum correction based on global wavefield continuation is effective.

Key words: near-surface problem, wave-equation, datum correction, double square root operator, observed surface settlement