Features of the Tien Shan newest orogen morphostructure

Abstract

Research subject. The concept of morphostructure implies the presence of a relationship between the relief forms of segments of the Earth’s crust and their structural and material content. This article describes the geological ensembles of the Tien Shan orogen, the tectonic structure and modern relief of which differ in their parameters from the general morphostructural plan and which, therefore, belong to the category of morphostructural anomalies. Materials and methods. The data presented in the article were obtained in the course of field structural-geological and morphostructural study of key segments of the Tien Shan orogen, as well as an analysis of materials from previous research, including the results of geophysical sounding of the Earth’s crust and geodesical monitoring of relative modern movements of reference points on the surface.Results. The article demonstrates that, against the background of the general linear-wave morphostructure of the Tien Shan orogen, there are areas whose relief and tectonic structure do not agree with the general tectonic plan of the mountain. Wi thin the considered region, different types of morphostructural anomalies are identified and described, reflecting the speci fics of the evolution and geotectonic position of individual volumes of upper-crust rock complexes: zones of concentrated deformation and tectonic joining; centrally symmetric structures formed on the site of paleoatolls; neotectonic protrusions of the granite basement; trans-regional zone of the Talaso-Ferghana Fault and other structures. Conclusion. The formation of morphostructural anomalies is associated with the presence of non-trivial geodynamic environments operating against the background of the tectonic regime common to the Tien Shan. The modern morphostructure of the Tien Shan is the result of interference between various geodynamic regimes and settings: a regime common to the entire territory of the orogen and particular regimes that manifest themselves sporadically and are reflected in the modern relief.