1. Compare the physical and tectonic maps of Russia with the map and explain why Southern Siberia is an alternation of mountain ranges, intermountain hollows, uplands and plateaus. Show them on the map.
The tectonic map shows that the central part of the mountains of Southern Siberia belongs to the Baikal folding region, which began more than 1.5 billion years ago. The Western Sayan Mountains and the Tuva Mountains are formed in the Caledonian folding era, and the extreme west and southeast – in Hercynian. The mountains of South Siberia are a very complex contact of different lithospheric plates, areas of collision and expansion of slabs. But the modern face of the territory was determined by the latest tectonic movements, when in the Neogene-Quaternary period the mountain structures were broken up into blocks, some of which were uplifted and some were lowered. In the areas of subsidence, hollows were laid, on the rising blocks – highlands and plateaus. The orographic
scheme does not show the basins, they are located between the ridges. The most famous and large basins are Minusinsk and Tuva.
2. Try to explain why the differences in the number and composition of the high-altitude belts of the mountains of Southern Siberia are related.
The number and set of high-altitude belts depend, first of all, on the height of the mountain system and on the position in the system of natural zones of the world. The lower altitude belt corresponds to the natural zone surrounding the mountain plains system. Further, the change of the high-altitude belts up the slopes of the mountains is analogous to the movement to the north. The barrier role of the mountains intercepting sediments and the hollow effect is of considerable importance. In the figure, the most diverse is the south of the highest Altai. A relatively simple structure is the high-altitude zonality of the northern Kodar ridge, located in the zone of light coniferous taiga.
3. The mountains of the south of Siberia experienced a “second birth”. How old can the mountains be – young or old? Argument your
answer. The mountains of Southern Siberia are called the reborn mountains. This is a special term for mountain structures that arose as a result of the latest tectonic movements on the site of ancient, almost destroyed mountain areas. For modern regenerated mountains, along with areas of sharply dissected erosion relief, high-elevated flat surfaces-a plateau-are characteristic.
4. Find and show on the map the location of the mountains and hollows. Give an assessment of their geographical location.
Describing and assessing the geographical location of the hollows, indicate between what ranges they are, how they are oriented. For example, the Kuznetsk Basin is located between the Kuznetsk Alatau and the Salair Ridge and stretches from the northwest to the southeast. Describe the minerals, climate and landscapes. So, in the Kuznetsk basin, where the largest in the Kuznetsk coal basin is located, in the conditions of sharply continental climate steppe landscapes with larch-birch forest-steppe areas were formed.
5. How can you explain the extreme diversity of natural landscapes of the belt of the mountains of Southern Siberia?
The variety of landscapes is explained by the variety of conditions in which they were formed: sharp differences in altitudes, climate changes, anthropogenic impact.
6. What minerals are rich in the mountains of Siberia and how are these minerals used?
The mountains of South Siberia are rich in metal minerals, in the intermontane basins there are large reserves of coal. The main mineral deposits are listed in Table 32.
7. Describe the barrier role of the belt of the mountains of Southern Siberia. How does it affect the nature of the surrounding areas?
Of course, the barrier role of the mountains of Southern Siberia is not as pronounced as in the Urals or the Caucasus, because the ranges are not oriented across, but along the direction of the prevailing western winds. Nevertheless, the main air masses are associated with the western air masses, which fall on the western windward slopes of Altai and Kuznetsk Alatau. The climate here is the least continental. The influence of the western circulation also appears on ridges above 2000 m. The climate is most continental and dry in closed intermountain hollows, especially in Tuva.