Coevolution of global brachiopod palaeobiogeography and tectonopalaeogeography during the Carboniferous

The global brachiopod palaeobiogeography of the Mississippian is divided into three realms, six regions, and eight provinces, while that of the Pennsylvanian is divided into three realms, six regions, and nine provinces. On this basis, we examined coevolutionary relationships between brachiopod palaeobiogeography and tectonopalaeogeography using a comparative approach spanning the Carboniferous. The appearance of the Boreal Realm in the Mississippian was closely related to movements of the northern plates into middle–high latitudes. From the Mississippian to the Pennsylvanian, the palaeobiogeography of Australia transitioned from the Tethys Realm to the Gondwana Realm, which is related to the southward movement of eastern Gondwana from middle to high southern latitudes. The transition of the Yukon–Pechora area from the Tethys Realm to the Boreal Realm was associated with the northward movement of Laurussia, whose northern margin entered middle–high northern latitudes then. The formation of the six palaeobiogeographic regions of Mississippian and Pennsylvanian brachiopods was directly related to “continental barriers”, which resulted in the geographical isolation of each region. The barriers resulted from the configurations of Siberia, Gondwana, and Laurussia, which supported the Boreal, Tethys, and Gondwana realms, respectively. During the late Late Devonian–Early Mississippian, the Rheic seaway closed and North America (from Laurussia) joined with South America and Africa (from Gondwana), such that the function of “continental barriers” was strengthened and the differentiation of eastern and western regions of the Tethys Realm became more distinct. In the Barents Ocean tectonic domain during the Pennsylvanian, the brachiopods on the northern margin of the Barents Ocean formed the Verkhoyansk–Taymyr Province, while those on the southern margin formed the Yukon–Pechora Province. The Mongolia–Okhotsk Province was formed by brachiopods of the Mongolia–Okhotsk Ocean tectonic domain. The Northern Margin of the Palaeo-Tethys Ocean Province and the Southern Margin of the Palaeo-Tethys Ocean Province were formed, respectively, by brachiopods on the northern and southern margins of the Palaeo-Tethys Ocean tectonic domain. South China and Southeast Asia were dissociated from the major continental blocks mentioned above, and formed the South China Province.