  We study resolutions of singularities of orbit closures in quiver
representations. We consider certain resolutions of singularities which have
already been constructed by Reineke, and we determine under which conditions
they are crepant. More specifically, we deal with quivers of type A3, An, D4.
Then, as an application of the results we have found, we construct several Fano
and Calabi-Yau varieties as orbital degeneracy loci.
