We measured differential cross sections and d~-y angular correlations for the scattering of 10 MeV deuterons on Mg, Mg, Si, and Si. The data were analyzed in terms of coupled channels in a 0+-2+ coupling scheme on the basis of a symmetric rigid rotator model and in the framework of the distorted wave Born approximation.The correlation data of Mg show a remarkable prolateoblate sensitivity. They can be described also in the distorted wave Born approximation, but only in the prior interaction form. For Si multistep processes can be indicated. The results are consistent with a prolate nuclear shape of ' Si.NUCLEAR REACTIONS " Mg 2 Si(d,d'y), Ed --10 MeV; measured inplane d~-y correlations. ' Mg ' Si deduced prolate-oblate nuclear shape, restriction of optical model parameters. Coupled channels and 0%'BA analyses, enriched targets.