The Kanayama unit of the Mesozoic Mino-Tamba accretionary complex in eastern southwest Japan is a thick milange unit composed mainly of abundant muddy matrix and variously sized clasts of chert, hemipelagic siliceous mudstone, and sandstone. Two episodes of deformation formed the milange fabrics: the first involved fragmentation of sandstone layers in response to mud injections; the second involved layer-parallel, noncoaxial shear that resulted in the mixing of pelagic to terrigenous clasts and the formation of S-C-like asymmetric fabrics with scaly foliation. The S-C fabrics exhibit a predominantly sinistral shear sense in plan view. After fold and tilt corrections, the restored slip motion inferred from the S-C fabrics indicates a bulk top-to-the-south shear. Combining the unit's terminal fossil age and radiometric age with a regional plate reconstruction model, these data suggest that the Kanayama milange formed along a dicollement during oblique subduction of the Izanagi plate in the Early Cretaceous.