SHELL CANADA <SHC> TO SELL TANKERS TO SOCANAV Shell Canada Ltd said its Shell Canada Products Ltd unit will sell three tankers, effective April one, 1987, to <Socanav Inc>. Terms were not disclosed. Shell also said it will contract exclusively from Socanav normal marine distribution requirements for domestic markets, with some exceptions, for an initial 10-year period. Shell also said its Shell Canadian Tankers Ltd unit will lay off 13 employees and that Socanav will offer jobs to 41 employees. The three Shell vessels are Lakeshell, Eastern Shell and Northern Shell, which range in size from 6,000 to 10,000 tonnes, Shell said. Shell Canada is 72 pct owned by Royal Dutch/Shell Group <RD>.