Structures of the late palaeozoic thrust belt in the Chinese South Tian Shan

Aiming to resolve contradictions in tectonic models and to establish a correlation between Chinese and Kyrgyz sectors of the South Tian Shan we carried out stratigraphic and structural studies in Chinese part of the belt along the Bayinbuluk—Kuqa transect. New data indicate that Chinese South Tian Shan is dominated by top-to-the-south structures, which were formed during the latest Carboniferous and Early Permian. Major allochthons of the Devonian carbonates, thrusted on the Gzhelian and Asselian turbidites, are revealed in the northern part of the belt. Imbricated thrust packages and recumbent folds in deeper marine Devonian and Carboniferous rocks are common in the South. Postkinematic granites yield U-Pb ages of 285–275 Ma, which indicate that thrust deformation ceased by the middle of the Early Permian. The same direction of motion and similar age of deformations in Kyrgyz and Chinese sectors of the South Tian Shan prove, that top-to-the-south structures were formed during the same structural episode, which corresponds to the main collisional stage within entire belt.