The subduction model proposes that the proto-South China Sea formed a subduction zone to its east, which subsequently, by the process of slab pull, subducted the proto-South China Sea beneath northwest Borneo. When the Dangerous Grounds collided with the Mesozoic granites of the Schwaner Mountains in Borneo, it brought an end to the subduction. This is due to the less dense Dangerous Grounds not having a big enough density contrast compared to the overlying plate. Therefore, with the end to subduction a suture was formed where the proto-South China Sea ceased subduction and the crustal margins came together. The proposed suture lies beneath Mount Kinabalu in northeast Borneo.