The ability of reflection seismic data to uniquely determine the subsurface velocity has been uncertain. This paper uses a tomographic approach to study the resolution of typical seismic survey configurations. The analysis is first carried out in the spatial Fourier domain for the case of a single horizontal reflector. It is found that for a ratio of maximum offset to layer depth of one, the lateral resolution is very low for velocity and interface depth variations of wavelengths of approximately two-and-a-half times the layer thickness. The resolution improves with an increase in the ratio of maximum offset to layer depth. The results of the analysis in the Fourier domain are confirmed by results from a least-squares tomographic algorithm. It is found that regularization of the tomography by adding damping terms suppresses the spurious oscillations resulting from the areas of low resolution at the expense of loss of resolution at the shorter spatial wave-lengths. Analysis of the single layer response for 3-D survey geometry shows that a 3-D acquisition with multiazimuthal coverage has the potential to significantly improve velocity determination.