Abstract:

Abstract:  Cenozoic deformation is well developed in the basin/range coupling regions on both sides of Tianshan Mountains, where is also a natural laboratory for studying the coupling dynamics of basin and range. Based on the comprehensive analysis of prior data and field measurements, and the analyses by ourselves, we mainly present in this paper the characteristics of Cenozoic deformation in both sides of Tianshan Mountains. It is obvious that the Cenozoic deformation in the south and north sides of Tianshan Mountains are both similar and different. The deformation transferred from the range to the basin, and the initiative time of the deformation in the south side is older than that in the north, and the crustal shortening and its rate in the south are larger than those in the north. The deformation in both sides also shows a segmental similarity in EWdirection, displaying a special deformation pattern of rhombic symmetry. Basement thrust systems are developed in the north side of Bogda Mountain (eastern Tianshan Mountains) and in the southwest side of western Tianshan Mountains. Strikeslip faulting took place not only in the south of the eastern Tianshan Mountains, but also in the north of the western Tianshan Mountains. Series of rows composed of folds and thrust systems grow on both sides of the central Tianshan Mountains. The comprehensive study suggests that the similarity and difference of the deformation resulted from the fardistance effect of the collision between the India and Asia Blocks and convergence afterward, and the earlypreserved relatively rigid prePaleozoic blocks and largescale fault systems within the LatePaleozoic Tianshan orogeny led to the formation of the Cenozoic deformation pattern of rhombic symmetry.

Key words: Key words: Tianshan Mountains; coupling of range and basin; Cenozoic structural deformation; geodynamics