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Two distinct styles of continental collision are observed in nature, i.e. lithospheric-scale subduction versus crustal-scale underthrusting. The former refers to a collision scenario where the lower plate subducts below the lithospheric mantle of the overriding plate, whereas the latter is characterized by the underthrusting of the subducting plate beneath the crust of the overriding plate. Systematic numerical models were constructed to study the dynamics of these two different collision modes. The model results indicate that low convergence rate and cold overriding plate contribute to the lithospheric-scale subduction, which incorporates limited shortening of the overriding lithosphere during collision. In contrast, the crustal-scale underthrusting requires relatively high convergence rate and hot/weak overriding plate, in which the thickened lithospheric mantle of the over-riding plate is progressively delaminated from the overlying crust and is replaced by the sub-horizontally underthrusted plate. The model results were systematically compared with four ongoing collisional orogens along the Alpine-Himalayan belt, i.e. the central-western Alps, the East Anatolian plateau, the Zagros-Iranian plateau, and the southern Tibetan plateau. It indicates that the lithospheric-scale subduction is widely observed and generally consistent with the natural orogens, for example, the Alps, Anatolia, and Zagros. On the other hand, the crustal-scale underthrusting is reconciled with the India-Asia collision zone, with respect to the geodynamic conditions, crustal-lithospheric structure, as well as the uplift history.