Abstract <p>Regional compression resulting from the Indo-Eurasian collision is the dominating neotectonic process at the Altai territory during the Late Cenozoic. The main relief factor is the release of the Earth’s crust blocks into the upper half-space of the reverse fault zones. The reverse faulting in combination with the right-lateral thrust movements controls planar topography of the mountain ranges. Dome structures prevailed at the beginning of the neotectonic phase in the Middle Cenozoic; they not always are inherited by later block structures. Faults bound the ranges and separate their composing blocks. They include right-lateral and left-lateral strike-slip faults, reverse and oblique-slip faults, normal faults and grabens. Right-lateral strike-slip faults are widespread in the Altai, which structures are angled to the main regional compression axis. Most of them have clearly seen reverse faulting component and are presented in the topography by 200–300 m high steps, linear parts of river valleys, and in places by chains of minor horsts. Reverse and strike-slip faults appear if the breaking movements are perpendicular to the regional compression axis; they form long 500 m and higher cross-regional steps, which are the most typical for the south of the Russian Altai. Normal and pull-apart faults do not form long structures; they fix the local tensile zones oriented at an acute angle to the compression axis and are represented in the topography by short up to 500 m high steps, broken in shape river valleys, and elongated graben-shaped lake basins. Within the Russian Altai there is a turn to the west of the main right-lateral thrust zones of the Mongolian Altai, which have a northwestern extension. This is due to the proximity of the platform area from the north, which does not allow shifting movements and only a small part of the horizontal amplitudes is extinguished by thrusting of the northern face of the Altai to the Biya-Barnaul depression and most of the horizontal displacement is compensated by the counterclockwise turn of the Russian Altai. At the same time, in the westerly end of the shear zones, the reverse-fault movements prevail. The blocks in the northern Altai have a variety of shapes and a transitional zone near the Biya-Barnaul border includes large, loosely fragmented blocks with less than 2000 m altitudes. It represents the linear warp zone separating the Altai from the adjacent stable blocks of Siberia and Kazakhstan. Together with the prevailing right-lateral thrust process in the Russian Altai there are faults and narrow grabens of the extension zones, for example the Teletskoe Lake and north-directed parts of the Katun, Anui and Charysh river valleys.</p>

Tectonic Relief of Russian Altai

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发表日期：

2025年6月26日

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I. Novikov,
G. Rusanov,
A. Agatova,
R. Nepop

摘要

Abstract

Regional compression resulting from the Indo-Eurasian collision is the dominating neotectonic process at the Altai territory during the Late Cenozoic. The main relief factor is the release of the Earth’s crust blocks into the upper half-space of the reverse fault zones. The reverse faulting in combination with the right-lateral thrust movements controls planar topography of the mountain ranges. Dome structures prevailed at the beginning of the neotectonic phase in the Middle Cenozoic; they not always are inherited by later block structures. Faults bound the ranges and separate their composing blocks. They include right-lateral and left-lateral strike-slip faults, reverse and oblique-slip faults, normal faults and grabens. Right-lateral strike-slip faults are widespread in the Altai, which structures are angled to the main regional compression axis. Most of them have clearly seen reverse faulting component and are presented in the topography by 200–300 m high steps, linear parts of river valleys, and in places by chains of minor horsts. Reverse and strike-slip faults appear if the breaking movements are perpendicular to the regional compression axis; they form long 500 m and higher cross-regional steps, which are the most typical for the south of the Russian Altai. Normal and pull-apart faults do not form long structures; they fix the local tensile zones oriented at an acute angle to the compression axis and are represented in the topography by short up to 500 m high steps, broken in shape river valleys, and elongated graben-shaped lake basins. Within the Russian Altai there is a turn to the west of the main right-lateral thrust zones of the Mongolian Altai, which have a northwestern extension. This is due to the proximity of the platform area from the north, which does not allow shifting movements and only a small part of the horizontal amplitudes is extinguished by thrusting of the northern face of the Altai to the Biya-Barnaul depression and most of the horizontal displacement is compensated by the counterclockwise turn of the Russian Altai. At the same time, in the westerly end of the shear zones, the reverse-fault movements prevail. The blocks in the northern Altai have a variety of shapes and a transitional zone near the Biya-Barnaul border includes large, loosely fragmented blocks with less than 2000 m altitudes. It represents the linear warp zone separating the Altai from the adjacent stable blocks of Siberia and Kazakhstan. Together with the prevailing right-lateral thrust process in the Russian Altai there are faults and narrow grabens of the extension zones, for example the Teletskoe Lake and north-directed parts of the Katun, Anui and Charysh river valleys.