Kazakhstania, also known as the Kazakhstan Block, is a small geological region in the interior of Asia. It consists of the area north and east of the Aral Sea, south of the Siberian craton and west of the Altai Mountains and Lake Balkhash. Politically, it comprises most of Kazakhstan and has a total area of around 1.3 million km². The Junggar basin in Xinjiang, China is also part of Kazakhstania, though sometimes referred to as the Junggar Block.
It is believed that present-day Kazakhstania is chiefly a mélange of early Paleozoic volcanic island arcs and some small continental terranes. These were joined together during the Ordovician to form what was at the time an isolated continent of its own. During the Carboniferous and Permian, Siberia collided with Kazakhstania to form the Altai Mountains, later Baltica collided in the Ural orogeny, creating the basis for most of present-day Eurasia.
Kazakhstania is mainly flat: only in the east near Karaganda are there mountains and these only rise to 1,565 metres (5,130 feet) in the Tarbagatay Range. Although most of Kazakhstania is arid and practically no water flows from the region to the oceans, there is extensive grazing of cattle, sheep and camels on the grasslands which cover most of the region today. Kazakhstania was too dry for extensive glaciation during the Quaternary. Kazakhstania contains as much as a quarter of the world's proven uranium reserves and is also one of the world's major source of lead, zinc, and antimony ores. On the southern boundary in the Turan Depression are large deposits of natural gas.
- Map of the Kazakhstan Block and surrounding areas
- Ordovician-Permian paleogeography of Central Eurasia