Zaysan fold system

Zaysan folded system - a large geotectonic structure that arose in the Hercynian era of folding , on the territory of the East Kazakhstan region , between the Genghis-Tarbagatai and Altai-Sayan folding systems. Consists of linear structural and formation zones (from southwest to northeast): Akulba ^{[ specify ]} - Shygys Altai, Rudny Altai , Irtysh crushing zone , Kalba Range , Shar, Zharma-Sauyr. Kerensky and Sharsky anticlinoria are composed of strongly metamorphosed Precambrian deposits. The cores of the Aleyskaya, Sinyushinskaya, and Revnyushinskaya anticlines consist of metamorphosed albite and dot-chlorite and quartz-albite-chlorite schists of the Lower Paleozoic . In places there are rocks of Ordovician and Silurian . Volcanic rocks of the Devonian are widespread in the areas of Akulba ^{[ specify ]} -Shygys-Altai synclinorium and Rudny Altai , and the zones of the Kalba ridge , the Irtysh collapse zone, the Shara, and Zharma-Sauyra are composed mainly of volcanic-terrigenous deposits. Late Paleozoic superimposed troughs compose coal-bearing strata, sometimes with porphyrites . In the era of Hercynian folding, intrusive magmatism was developed. Deposits of polymetals (Ridder-Sokolovskoe, Tishinskoe, Leninogorskoe), iron (Markakolskoye), gold, limestone, etc. are confined to the folded system.