The Uralian orogen (
sensu stricto) occurred between three Palaeozoic continents,
Baltica,
Kazakhstania, and
Siberia. In the late Precambrian, the northeast margin of Baltica was deformed in the
Timanide and
Cadomide orogenies or the assembly of the
Pannotia supercontinent. The break-up of this supercontinent opened the Palaeo-Uralian Ocean, in which a number of unidentified continental fragments
rifted from Baltica. As Baltica collided with Laurentia to form Laurussia,
island arcs and other
microcontinents were
accreted to Baltica in the Late Devonian-Early Carboniferous. In the Ordovician-Silurian, Kazakhstania formed separately when
subduction-driven growth accreted crust to a series of small, late Precambrian microcontinents. In the early Late Carboniferous, Kazakhstania began to collide with Laurussia as the Palaeo-Uralian ocean subducted beneath the margins of the latter. The northern continuation of the Ural mountains, the Pay-Khoy-Novaya Zemlya foldbelt, is the result of the collision between Laurussia and Siberia in the Early Jurassic. The southern continuation of the Ural mountains, the southern
Tian-Shan mountains, formed in the late Palaeozoic with the closure of the Turkestanian Ocean, an Ordovician-Carboniferous southern branch of the Palaeo-Uralian Ocean. Tian-Shan remained a stable
platform until the Alpine-Himalayan orogeny in the Pliocene-Quaternary. ==See also==