Paleo-Tethys Ocean

In the first scenario, mantle plumes caused the opening of the Atlantic and the break-up of Pangaea and the closure of the Tethyan domain was one of the consequences of this process; in the other scenario, the longitudinal forces that closed the Tethyan domain were transmitted latitudinally in what is today the Mediterranean region, resulting in the initial opening of the Atlantic.

[5] The Paleo-Tethys Ocean began to form when back-arc spreading separated the European Hunic terranes from Gondwana in the late Ordovician, to begin moving toward Euramerica (also known as the Old Red Sandstone Continent) in the north.

[6][7] In the Early Devonian, the eastern part of Paleo-Tethys opened up, when the Asiatic Hunic terranes, including the North and South China microcontinents, moved northward.

[7][8] These events caused Proto-Tethys Ocean to shrink until the Late Carboniferous, when the Chinese blocks collided with Siberia.

[7] In the Early Carboniferous however, a subduction zone developed south of the European Hunic terranes consuming Paleo-Tethys oceanic crust.

Location of the Paleo-Tethys Ocean circa ~250 million years ago
Location of the Paleo-Tethys Ocean circa 380 million years ago [ 1 ]
Image of Paleo-Tethys Ocean, before the Cimmerian Plate moved north, which made the ocean close, the Paleo-Tethys Ocean closed off about 180 mya. ~290 mya ( Early Permian ).
The Cimmerian plate starts to move northward, closing the Paleo-Tethys Ocean, while the Tethys Ocean begins to open from the south. ~249 mya (Permian-Triassic boundary).