Geological time, mountain building and minerals

In the Archean and Proterozoic eras the area of Central Asia lay under the sea. In the Paleozoic, islands began to rise within the Tethys Sea, and in the Caledonian and Hercynian foldings the Kazakh uplands, much of the Tien Shan and the Central Kyzylkum mountains appeared. The Alpine folding in the Neogene period of the Cenozoic raised the Pamir, Kopet Dag and Hindu Kush, and renewed the Tien Shan; mountains are still rising today. Because the Pamir and Tien Shan lie where the Eurasian and Indian lithospheric plates collide, earthquakes are frequent in the region (for example Tashkent in 1966 and Gazli in 1976 and 1984). Central Asia is rich in minerals: hard coal at Karaganda and Ekibastuz, brown coal at Angren in the Ohangaron valley, oil and gas in the Fergana, Karakum, Ustyurt and Kashkadarya areas, copper at Almalyk and Zhezkazgan, phosphorite in the Kyzylkum and Karatau, and marble at Nurota.