In order to investigated the nature of the seismic velocity distribution beneath western Canada, a set of seismograms recorded between 14¿ and 40¿ of epicentral distance has been deconvolved by a simple scheme. The source functions required for the deconvolutions have been obtained from seismograms between 30¿ and 40¿. The deconvolved seismograms clearly indicate the presence of multiple arrivals, whose differential travel times and relative amplitudes changes drastically from one group of records to another. On the basis of the relative amplitude and differential travel time patterns, the seismograms have been divided into five groups.