Geological history of Earth with highly seasonal rainfall patterns. Deserts seem to have been widespread on Pangaea. The Mesozoic extended roughly from . After the vigorous convergent plate mountain-building of the late Paleozoic, Mesozoic tectonic deformation was comparatively mild. Nevertheless, the era featured the dramatic rifting of the supercontinent Pangaea. Pangaea gradually split into a northern continent, Laurasia, and a southern continent, Gondwana. This created the passive continental margin that characterizes most of the Atlantic coastline (such as along the U.S. East Coast) today. The Triassic Period extends from about 252.17 ± 0.06 to 201.3 ± 0.2 Ma. During the Triassic, almost all the
South China (continent) Ocean. By the Late Carboniferous (300 million years ago), while North China collided with Siberia and Kazakhstania, completely closing the Proto-Tethys Ocean, South China became an independent continent. For much of the Permian Period, South China remained in the tropical latitudes. And also, while most of the giant lycopods of the Carboniferous disappeared, giant lycopods remained in South China, since its isolation from the now formed Pangaea. Cimmeria, a microcontinent that consisted of today's Tibet, Iran, Turkey, and parts of Southeast Asia rifted away from Gondwana (just as North and South China did earlier), and was heading towards Laurasia. Paleo-Tethys