Tethys Ocean
In the early Permian, the Neo-Tethys Ocean opened behind the Cimmerian terranes (Sibumasu, Qiantang, Lhasa) and, in the late Carboniferous, the Palaeo-Tethys Ocean closed in front. The eastern branch of the Palaeo-Tethys Ocean, however, remained opened while Siberia was added to Laurussia and Gondwana collided with Laurasia.