Relief and Exogenous Processes on the Okinskaya Depression (Eastern Sayan)
The issues of the Okinskaya depression (Eastern Sayan) forming and Geomorphological aspects of the modern development are considered in this article. The characteristic of the main morphological features of the depression is given among which the asymmetry of its sidewalls and linearity and deepness. The main particulars of the depression neotectonics development are marked, which together with relief analysis allow to assign it to the «little» depression of the Baikal type. The structure of the Oka river valley, that occupies the bigger part of the depression, has a series of low and middle altitude terraces, formed during Late Pleistocene and Holocene as a result of runoff regime changing, which is related to influence of tectonics, climate, volcanism and ancient glaciations. The middle scale map of the leading modern exogenous processes and landforms is compiled. The map based on principles and the methods, which were worked out by author and approved on the wide materials about Baikalian type of depressions. The analysis of the map to estimate the rank and the role allows of various relief formation exogenous processes, among which the fluvial, sloping erosional and sloping cryogenic. Frequently, the cryogenic processes accompany of leading processes, which are developed on the flat surfaces with various genesis (terraces above flood-plains, mountain aprons).
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