Improved methods of processing seismic data which comprise amplitude data assembled in the offset-time domain in which primary reflection signals and noise overlap are provided for. The methods include the step of enhancing the separation between primary reflection signals and coherent noise by transforming the assembled data from the offset-time domain to the time-slowness domain. More specifically, the assembled amplitude data are transformed from the offset-time domain to the time-slowness domain using a Radon transformation according to an index j of the slowness set and a sampling variable .DELTA.p; wherein.times..times..mu..times..times..times..times..DELTA..times..times- . ##EQU00001## .DELTA.p is from about 0.5 to about 4.0 .mu.sec/m, p.sub.max is a predetermined maximum slowness, and p.sub.min is a predetermined minimum slowness. Alternately, an offset weighting factor x.sup.n is applied to the assembled amplitude data, wherein 0