Pangaea formation of not only the Ural Mountains but also the supercontinent of Laurasia. This was the last step of the formation of Pangaea. Meanwhile, South America had collided with southern Laurentia, closing the Rheic Ocean and forming the southernmost part of the Appalachians and Ouachita Mountains. By this time, Gondwana was positioned near the South Pole and glaciers were forming in Antarctica, India, Australia, southern Africa and South America. The North China block collided with Siberia by the Late Carboniferous, completely closing the Proto-Tethys Ocean. By the early Permian, the Cimmerian plate split from Gondwana and headed towards Laurasia, thus
Mesozoic nearly their present forms, though not their present positions. Laurasia became North America and Eurasia, while Gondwana split into South America, Africa, Australia, Antarctica and the Indian subcontinent, which collided with the Asian plate during the Cenozoic, giving rise to the Himalayas. The Triassic was generally dry, a trend that began in the late Carboniferous, and highly seasonal, especially in the interior of Pangaea. Low sea levels may have also exacerbated temperature extremes. With its high specific heat capacity, water acts as a temperature-stabilizing heat reservoir, and land areas near large bodies of water—especially oceans—experience less variation in temperature. Because