What type of mountains are single mountains? Mountains, differences in mountains by height and origin

The entire land surface can be divided into two parts - plains and mountains. Between them there are also transitional forms, for example: hilly surface, elevated plain, plateau, highland, peneplain, plateau. The mountains are very diverse. If a hill has a relative height of more than 200 m, well-defined slopes and a bottom line, it is - mountain. Extensive areas earth's surface, elevated above 500 m above sea level, with sharp fluctuations in heights at close range, are called mountainous countries(Caucasus, Ural, mountains Southern Siberia). Peaks- these are separate mountains that rise noticeably above general level mountainous country (Elbrus in the Caucasus, etc.). In the Sayan Mountains, Transbaikalia, Kazakhstan and the Far East, hills or mountains of a rounded, often conical shape with a flattened or rocky top are called hills, as well as the volcanoes in Kamchatka and Kuril Islands, in the Caucasus and Crimea. A special type of relief that arose as a result of the long-term destruction of a mountainous country - small hills, for example in Central Kazakhstan. It is characterized by randomly scattered hills and small ridges of them various shapes, sometimes with slightly pointed tops and a wide base, a relative height of 50-100 m. They are separated by wide flat basins, often occupied by lakes, or valleys.

Mountain range.

Mountain peak.

Mountain ridge.

As a result of the tireless work of external destructive forces of nature, mountains are eroded, their peaks are smoothed out and lowered. Millions of years will pass, and the mountains will turn into almost a plain (peneplain).

Kar and cirque glacier.

Section of a folded mountainous country after its erosion.

Section of folded block mountains (stepped horst).

Island table-remnant mountains.

Island tectonic mountains.

Typical for the relief of mountainous countries mountain ranges- mountain structures stretched over long distances with a well-defined axis in the form of a single watershed line, along which the highest altitudes are grouped. The mountain range has two slopes, often asymmetrical, oriented in opposite directions, often of different steepness. The line of intersection of the slopes, the top part of the ridge along which the watershed line runs, is called mountain ridge. It can be sharp, round, plateau-shaped, jagged. By pass saddles, that is, wide depressions with gentle slopes, the mountain ridge is divided into individual peaks or groups of them. A series of ridges linearly elongated in one direction, separated by transverse valleys, saddles and bearing different names, is mountain range. A low mountain range with soft, rounded peaks is called mountain ridge. Usually these are the remains of ancient, destroyed mountains, for example the Timansky and Donetsk ridges. If such a weakly dissected rise with a clearly defined sole is approximately equally elongated in length and width, then this mountain range(Putorana mountain range in Siberia, Kilimanjaro in Africa). A short and narrow branch from a mountain range - mountain spur. The area of ​​intersection of two or more mountain ranges is a mountain junction. Usually the mountains here are high and inaccessible - the Ukok and Tabyn-Bogdo-Ola plateaus in Altai, etc. If ridges of the same origin are located in a certain order, for example, in the form of a series of mountain ranges extending linearly (Urals, Caucasus, Alps, Cordillera, Appalachians) , or radiating from a common mountain node (Altai), or bordering a highland (Pamir-Alai), then such a set of ridges is called mountain system. Low-lying edges of mountainous countries, systems or ridges, transitional to adjacent plains with hilly or low-mountain terrain - foothills.

According to their height, mountains are divided into low- from 200 to 700-800 m above sea level with rounded peaks (for example, the mountains of the Middle Urals). There are also low mountains with angular peaks, sharp-angled ridges, steep slopes, deep valleys: spurs of the Tien Shan, ridges of Transcaucasia. Mid-height mountains - with an absolute height of 700-2000 m, slope steepness of 10-25°, depth of dissection of 500-1000 m. They are characterized by smoothed, soft, rounded outlines of the peaks, gentle slopes. They are covered with forests and do not rise above the snow line, such as mountains Southern Urals. But sometimes they have alpine forms - pointed peaks, a narrow jagged ridge. Such mountains are distributed mainly in the North: the Polar Urals, the mountains of the island of Novaya Zemlya, and in some places on Kola Peninsula. High mountains - with an absolute height of more than 2000 m, a depth of dissection of at least 1000 m and with a slope steepness of more than 25°; their ridges are narrow, jagged and rise above the snow line. These are the mountains of the Pamirs, Tien Shan, Greater Caucasus, Himalayas, Cordillera North America, Andes South America etc.

Mountain peaks can be flat (table mountains), have steep or stepped slopes. In such mountains, their flat top is usually composed of a durable layer (limestone, sandstone, traps). Table mountains arise when stratified plains (for example, the Turgai Plateau) are dissected by flowing waters. Domed, pyramidal and pointed tops (peaks) are common. The constantly snow-covered peaks in Altai are called proteins, and bare peaks, above the limits of forest vegetation, - loaches; They are usually dome-shaped. Example - Kitoi char in the Eastern Sayan. In the top parts of the mountains, at the level of the snow line, cup-shaped depressions are formed under the influence of small glaciers, snowfields and frost weathering. This punishment, or circuses. Rear and side walls The kars are steep, often vertical, the bottom is gently concave, occupied by a glacier, firn or lake. As a result of the gradual cutting of the internal walls of the caves into the mountain range, when this occurs simultaneously with different sides, a separate mountain of a special pyramidal, triangular shape appears. This Carling. Example - Ushba in the Caucasus, Matterhorn in the Alps.

Gently undulating ridges and elevated interfluves in the steppe Trans-Volga region on the watershed of the Volga and Ural are called cheeses(General Syrt, Chalk Syrt, etc.). In the Tien Shan, highly raised wavy surfaces are called syrts - the remains of ancient leveling surfaces. Occupied by steppes and semi-deserts, they are found at high altitudes - 3500-4000 m.

Mountains are not only characteristic of land. At the bottom of the oceans and seas there are steep slopes stretching from hundreds to several thousand kilometers. rock formations, individual peaks of which sometimes rise above the surface of the sea in the form of islands. On the ocean floor, underwater ridges are blocky, folded-blocky, and volcanic. Seamounts are often larger than mountains on land.

Based on their origin, mountains are divided into tectonic, volcanic and erosional. Tectonic mountains arose as a result of displacement earth's crust In mobile zones of the earth's crust, rock strata are crushed into folds of varying sizes and steepness.

So, mountains or mountain structures are vast territories with a folded and folded-block structure of the earth's crust, raised to several thousand m above sea level. They are characterized by sharp fluctuations in heights. The mountains stretch for many hundreds and thousands of kilometers. Some mountains are elongated in a straight line (Pyrenees, Greater Caucasus), others are elongated in an arcuate manner (Carpathians, Alps, Lesser Caucasus). The highest peaks reach 7-8 thousand meters in height or more (Chomolungma in the Himalayas - 8848 m).

Mountains arise in the process mountain building, when forces acting in the mantle and crust cause tectonic movements, as a result of which the rocks that make up the earth’s crust are uplifted and deformed. This is how it was formed large number hills. They were created by movements that disrupted the structure of the earth's crust and caused dislocation its layers, i.e., disruption of their original occurrence. This is how the face of the earth's surface changes. Rock layers formed at the bottom of seas and lakes or on land in a horizontal or slightly inclined position are removed by these movements from their original position, raised up, lowered down, bent into folds, torn; at the same time, some sections of the earth's crust seem to rear up, tilt, completely overturn, and crawl on top of each other. Thus, in the process of mountain building, mountains arise, which, depending on the nature of the processes that created them, are divided into two main types - folded and faulted.

Based on the time of manifestation, tectonic movements are usually divided into modern, recent and ancient, occurring throughout the entire geological history of the Earth. In our time, only those mountains have survived on Earth, during the emergence and uplift of which the internal forces that created them exceeded the speed of exogenous processes of destruction and demolition ( denudation) rocks leading to leveling of the earth's surface.

In the geological history of the Earth, several eras of mountain building or folding are distinguished. They manifested themselves in the moving belts of the Earth - geosynclinal areas. From the geography course you know in what geological time these folds occurred and what they are called and what arose in these eras mountainous countries. And if you forgot, then take a look at the geochronological table in the textbook, or even better, at the large colorful table on the wall of the school geography office.

Block mountains are formed by sections of the earth's crust that have risen along tectonic faults. They are very massive, with steep slopes and poorly dissected. This horsts, separated grabens. Fold-block mountains - initially formed folded mountains, then destroyed and, under the influence of secondary tectonic processes, broken by cracks, again raised to different heights.

Volcanic mountains composed of products of volcanic eruptions and have a characteristic conical shape. Finally, eroded mountains formed as a result of erosion large region, high above the surrounding area. Surviving denudation and erosion (destruction by water and wind), stronger areas of the once higher surface form isolated hills - remnant mountains.

General concept. A mountain is usually called any pronounced rise, the base, slopes and top of which can be relatively easily distinguished. Free-standing mountains are extremely rare. Most often, mountains are combined into large groups, and their bases closely merge, forming a common skeleton, or the base of the mountains, clearly rising above the neighboring plain regions.

Based on the location of the mountains in the plan, isolated mountains, mountain ranges and mountain ranges are distinguished. The first, that is, free-standing mountains, as already mentioned, are relatively rare and are either volcanoes or the remains of ancient destroyed mountains. The second, i.e. mountain ranges, are the most common type of mountainous areas.

Mountain ranges usually consist not of one, but of many rows of mountains, sometimes located very closely. As an example, we can point to the Main Caucasus Range, along the northern slope of which at least four more or less clearly defined rows of mountains are distinguished. Other mountain ranges have a similar character.

Mountain ranges They are vast mountain uplifts, equally developed in both length and width.

Large mountain ranges are rare. Most often they form separate sections of mountain ranges. An example of a large, highly dissected massif is the Khan Tengri mountain range.

The height of mountains is always measured vertically from the base to the top or from ocean level and also to the top. The height from the bottom to the top is called relative. The height from ocean level to the top is absolute. Absolute height makes it possible to compare the heights of mountains regardless of where they are located. In geography, absolute heights are almost always given.

Depending on their height, mountains are divided into low(below 1 thousand), average(from 1 to 2 thousand. m) And high(above 2 thousand m). When it comes to mountain ranges or mountainous areas, then they usually include: small mountains, middle mountains And highlands. Examples of small mountains are the Timan Ridge, the Salair Ridge, as well as the foothills of many mountainous countries. Examples of middle mountains in the USSR are the Urals, the mountains of Transbaikalia, Sikhote-Alin and many others.

Types of mountains, identified on the basis of their height, are also characterized by relief features. For example, the highlands are characterized by sharp peaks, jagged ridges and deeply incised valleys (Fig. 235, 1). The highlands are also characterized by snowy peaks and glaciers. Mountains of medium height (or medium altitude) usually have rounded and seemingly smoothed shapes of the peaks and soft outlines of the ridges (Fig. 235, 2). The same, only even more smoothed forms are characteristic of small mountains. But here already great value gains relative height. If individual mountains of small mountains do not rise above the total surface above 200 m, then they are no longer called mountains, but hills.

Finally, mountains are also divided according to their origin. This division by origin is especially important for us, because it largely determines the character, structure, and location of the mountains. Depending on the origin (genesis) there are:

1) tectonic mountains,

2) volcanic mountains,

3) mountains are erosive.

We will analyze each of these types of mountains separately. Tectonic mountains, in turn, are divided into folded, folded-block and table-block.

Fold mountains. Let us recall that we call folded mountains those mountains in which folding clearly predominates. Fold mountains are found on all continents and many islands and are perhaps the most common, and fold mountains are the highest in height.

Mountains consisting of one fold (anticline) are relatively very rare. Much more often, mountain ranges consist of many parallel folds. In addition, the folds are usually much shorter in length than the ridges, due to which there may be several folds along the line of one ridge.

The very shape of the fold (in plan) largely determines the elongated shape of the ridges of folded mountains. Indeed, most of the fold mountains have characteristic shape(Urals, Greater Caucasus, Cordillera).

Fold mountains usually consist of a series of parallel mountain ranges. In most cases, mountain ranges are located very close to one another, and, merging at their bases, form a wide and powerful mountain range. Mountain ranges stretch for hundreds and sometimes thousands of kilometers (the Caucasus Range is about 1 thousand. km, Ural over 2 thousand km). Most often, large ridges (in plan) have an arcuate shape and less often a rectilinear one.

Examples of arcuate ridges are the Alps, Carpathians, and Himalayas; examples of rectilinear ones are the Pyrenees, the Main Caucasus Range, the Urals, the southern part of the Andes, etc.

There are often cases when mountain ranges branch and even diverge like a fan. Examples of branching ridges are the mountains of the Pamir-Alai, Southern Urals and many others. Instead of the word branching, many authors use the word virgation. In cases where the branches of the ridges extend under very acute angle or located parallel to each other, the term “on-scene” arrangement of ridges is sometimes used.

Folds that appear on the surface of the Earth, under the influence of weathering, the work of flowing waters, the work of ice and the activity of other agents, immediately begin to collapse. Anticlines, as the most elevated parts of folded mountains, are destroyed first. The rapid destruction of anticlines is partly facilitated by the fracturing characteristic of bends. Therefore, when severe destruction folds, valleys often appear in place of anticlines (anticlinal valleys), and in place of synclines there are mountain ranges. And the steeper the folds, the more intense the destruction of anticlines. As a result, the observed forms of mountains do not always correspond to structural forms, that is, forms determined by anticlines and synclines.

In cases where mountains, chains and ridges arise on the site of the wings of an anticline, the dip of the strata usually occurs only in one direction. The structure of such mountain chains is called monoclinal. The ridges or chains of mountains that arose on the site of the wings of a destroyed anticline are called cuestas, cuesta ridges, or cuesta chains. Asymmetry of slopes is typical for cuestas. The cuesta terrain is wide; distributed on all continents. An example is the northern foothills of the Caucasus.

Mesa Mountains are relatively rare. They arise on the site of lowland countries broken by faults, most often composed of horizontal strata. Elevated areas form mountains, usually table-type. The degree of elevation of areas can be different (from tens of meters to thousands of meters). It is difficult to notice any pattern in the distribution of rises and falls here. A typical example of table-block mountains is part of the Jura Mountains (Table Jura), as well as the Black Forest, Vosges, and some parts of the Armenian Highlands. An example of raising table forms to a lower height is Samara Luka. There are many very high table rises in southern Africa.

Much more widespread fold-block mountains. The history of the formation of folded block mountains is quite complex. Let us consider, as an example, the main stages of the development of Altai. First, on the site of modern Altai (at the end of the Paleozoic), a high folded mountainous country arose. Then the mountains gradually collapsed and the country became a hilly plain. During the Tertiary period, this leveled section of the earth's crust, under the influence of the internal forces of the Earth, broke into pieces, with some parts rising and others falling. The result was a complex mountainous country, the ridges of which were located in a variety of directions. Examples of folded-block mountains in the USSR are the Tien Shan, Transbaikalia, Bureinsky Mountains and many others.

Volcanic mountains we are already quite familiar. Let us only note the special nature of the destruction of volcanic mountains under the influence of external agents.

Peaks high volcanoes, like the peaks of other high mountains, are subject to vigorous processes of physical weathering. Here, as in other mountains, under the influence of sharp temperature fluctuations, powerful accumulations of rocks, stones and boulders are formed. Just like in other mountains, “stone streams” descend down the slopes. The only difference is that the “stone flows” descend not only along the outer slopes of the cone, but also along the inner slopes of the crater. On higher volcanic mountains glaciers develop, the destructive work of which is already known to us.

Below the snow line, the main destroyers are rainfall. They cut through potholes and ravines radiating from the edges of the crater along the internal (crater) and external slopes (Fig. 236). These erosion grooves on the outer and inner slopes of the volcano are called Barrancos. At first, the barrancos are numerous and shallow, but then their depth increases. As a result of the growth of the outer and inner barrancos, the crater expands, the volcano gradually lowers and takes the shape of a saucer surrounded by a more or less raised rampart.

As for laccoliths, they first lose their outer cover, consisting of sedimentary rocks. First, this cover is destroyed at the top, then on the slopes; at the base, the remains of the cover, together with deluvial cloaks, last much longer. Laccoliths freed from the cover of uplifted sedimentary rocks are called opened(or prepared) laccoliths.

Erosion mountains. By the name erosion mountains we mean mountains that have arisen mainly as a result of the erosive activity of flowing waters. Such mountains can arise as a result of the dissection of plateaus and flat hills by rivers. An example of such mountains is the many interfluve mountains of the Central Siberian Plateau (Vilyuisky, Tungussky, Ilimsky, etc.). They are characterized by table shapes and box-shaped valleys, and in some cases even canyon-shaped ones. The latter are especially characteristic of a dissected lava plateau.

Much more often, mountains of erosion origin are observed within the middle mountains. But these are no longer independent mountain systems, but parts of mountain ranges that arose as a result of the dissection of these ranges by mountain streams and rivers.

Vertical zonation of landforms in the mountains. Each ridge, each mountain range often differs from each other in its relief forms. It is enough to compare, for example, the shapes of peaks and ridges with the highlands of the middle mountains. The former are distinguished by sharp peaks and jagged ridges, the latter, on the contrary, have soft, calm outlines of both peaks and ridges (Fig. 235).

This striking difference is due to many reasons, but the most important of them is their altitude above sea level or, more precisely, the climatic conditions that exist at various heights. IN mountain zone, located above the snow line, the water is predominantly in a solid state (i.e., in the state of snow and ice). It is clear that there can be no streams or rivers there, and therefore, the erosive activity of flowing waters will be absent. But there are snow and ice there, which carry out tireless and highly peculiar work.

The situation is completely different in the lower zones, where the main agents are flowing waters. It is clear that the forms of relief of high mountains that arise under certain conditions will differ sharply from the forms of mountains that arise under other conditions.

As you rise upward, the physical-geographical conditions do not change immediately, but more or less gradually. It is clear that relief forms, determined by various physical and geographical conditions, will also change gradually. Let us dwell on the relief forms of the three most typical zones: high mountains, middle mountains and low mountains.

Landforms of high mountains. Frosty weathering, the work of snow and ice - here the most important factors, which most affect mountains rising above the snow line. The thin, clear air favors the heating of steep slopes devoid of snow cover. Clouds that temporarily cover the sun lead to rapid cooling. Thus, here at high altitudes, the rocks that make up the mountains are subject to not only daily, but also more frequent temperature fluctuations. The latter creates exclusively favorable conditions for frost weathering, and the presence of steep slopes helps weathering products quickly roll down and expose the surface of rocks for further weathering.

Frost weathering in the mountains is greatly aided by winds, the speed of which, as is known, increases significantly with altitude. Therefore, the winds here are capable of blowing away (and blowing out of cracks) not only small dust particles, but also larger debris.

The variety of rocks that make up the mountains leads to uneven weathering. As a result, areas folded more strong rocks, turn out to be highly elevated above the general level of areas composed of less durable rocks. With further frost weathering, highly elevated areas take the form of sharp peaks, peaks and ridges, which gives the ridges of mountain ranges a jagged shape.

In cases where the rocks are homogeneous, the pointed peaks eventually round out and become flat. On their surface, as a result of the same frost weathering, entire “seas” of rocks and stones accumulate. On slopes, and especially on steep ones, the products of frost weathering slide down in huge “rock flows”, forming colossal screes; Screes below the snow line are washed away by flowing waters. Talus that descends into glacier feeding areas and onto the edges of glaciers is carried away by glaciers. This is how the steep slopes of high mountains are unloaded from frost weathering products.

In high mountains, in addition to frost weathering, as already mentioned, snow and ice carry out enormous destructive work.

We have already talked enough about what forms of relief arise as a result of glacial and steam-forming activity. These forms will be dominant within the highlands. Above the modern snow line, sharp peaks, peaks and jagged ridges with cirques and glacial cirques usually catch the eye. Near the snow line there are glacial valleys with moraines and cirques. Even lower are traces of ancient glaciers and pits, at the bottom of which there are lakes or swamps or simply a drainage funnel.

Highland landforms were first studied in the Alps. Hence, all high mountains with sharp peaks, peaks, sharp jagged ridges, ravines, snow and glaciers began to be called mountains alpine type. Along with this, all the forms characteristic of high mountains, often in geographical literature called alpine forms.

Landforms of low and middle mountains. Let us now turn to the lower sections of the mountains, which, based on their heights and dominant forms, can be classified as small and medium mountains. There are no longer eternal snows or glaciers here.

Sometimes, however, there may be traces of ancient glaciations, more or less modified by the work of flowing waters and other agents. These are usually dilapidated troughs, carts and circuses, along the bottom of which there are lakes and rivers. In some places, remnants of moraines, smoothed rocks and typical glacial boulders have been preserved.

In mountains of medium altitude, frost weathering is much less pronounced, occurring only during the cold periods of the year. True, chemical and organic weathering occurs more intensely here, but the area of ​​distribution of this weathering is much smaller. This happens because the slopes of the mountains we characterize are more sloping, due to which weathering products often remain in place and delay further weathering. In the same areas where rocks come to the surface, they quickly weather and take on various, sometimes very characteristic, shapes.

If above the snow line the main destroyers were frost weathering, snow and ice, then here the main destroyers are flowing waters.

Mountains are generally characterized by a large number of rivers and all kinds of watercourses. Even in desert countries, mountains are always rich in water, because the amount of precipitation usually increases with height. The Tien Shan and Pamir-Alai mountains in Central Asia, from where such powerful rivers as the Syr-Darya and Amu-Darya receive their food, can be very indicative in this regard.

Mountain rivers are distinguished by a large slope of their channels, rapid current, an abundance of rapids, cascades and waterfalls, which determines their enormous destructive power. Finally, it should be noted that mountain rivers, fed by meltwater from snow and glaciers, in summer time Every day there is a large rise in water levels, which also increases their destructive power. All this taken together leads to the fact that the mountain slopes are cut through by a large number of transverse valleys. The latter often have the character of gorges. Depending on the strength of the rocks composing their slopes, gorges can be very deep and narrow. But, no matter how strong the rocks are, the steep slopes of the gorges are still gradually destroyed, become sloping and the gorges turn into ordinary wide valleys.

If the height of the mountains does not exceed the height of the snow line, then all the most important work in destroying the mountains is done by rivers. The upper reaches of mountain streams, cutting into the slopes, reach watershed ridges. Here they meet the headwaters of rivers on the opposite slope, and their valleys little by little unite and cut the mountain ranges into pieces. As the rivers continue to flow, the mountain ranges break up into separate mountains, which in turn fall apart. Thus, in place of mountain ranges, as a result of the work of flowing waters alone, hilly countries can appear. The lower the mountains become, the more sedimentary their slopes become, and the rivers flowing from the slopes can no longer have the same destructive force. Nevertheless, the rivers continue their work. They deposit destruction products at the bottom of valleys, fill basins and erode slopes. Ultimately, the mountains can be destroyed to the ground, and in their place a leveled, slightly hilly surface will remain. Only rare preserved, isolated mountains still remind one of the mountainous country that was once here. These remaining isolated mountains are called outliers mountains, or witness mountains(Fig. 237 a, b, c). The leveled, slightly hilly surface that remains in place of the mountains is called peneplain, or simply a leveled surface.

If areas of low and medium mountains find themselves in dry climate conditions (in deserts and semi-deserts), then wind becomes of great importance in the formation of small forms. The wind, as already mentioned, helps weathering, carrying away particles of the resulting loose rocks. In addition, in desert countries the wind often carries sand. Under the impact of grains of sand, resistant rocks are polished, while less resistant rocks are destroyed.

The process of destruction of mountains occurs so quickly that if the mountains ceased to experience uplift, then they would all be destroyed to the ground within one or two geological periods. But this does not happen, because under the influence of the internal forces of the Earth, the growth of mountains (uplift) usually continues very for a long time. So, for example, if the Ural Mountains, which arose as a high mountainous country at the end of the Paleozoic era, had not experienced further uplifts, they would have disappeared long ago. But thanks to repeated uplifts, despite continuous destruction, these mountains continue to exist.

When mountains are destroyed, two cases are possible. The first case: the rise of mountains proceeds more slowly than their destruction. Under these conditions, the height cannot increase, but can only decrease. When the uplift of mountains occurs faster than destruction, then the mountains rise.

To understand the character of each mountain we study, it is necessary to pay attention to special attention for the following points:

1. For folded mountains - the time of formation of the first folds and the time of formation of the last folds. For blocky ones - the state of a given mountainous country before the onset of faults and the time of the first and last movements of layers of the earth's crust along cracks.

2. The state of the mountains at the beginning of the Ice Age and during the glaciation period.

3. The state and life of mountains in post-glacial times.

The first, in addition to the age of the mountains, gives us an idea of ​​the main large forms and location of the ridges themselves. In addition, here we learn about the nature of rocks and the way they are deposited, which is of great importance in the further formation of mountains.

The second, i.e., the state of the mountains at the beginning of the Ice Age and during the glaciation period, is especially important for those mountains that were subject to glaciation. Glaciers, depending on their nature (continental ice, valley glaciers, etc.), can greatly change even large forms of mountain relief.

The state of the mountains in post-glacial times largely determines the nature of the details of the forms. Climate is of greatest importance in this case. For example, in cold climates, frost weathering and the work of snow and ice can occur at all altitudes. Therefore, here not only high mountains, but also mountains of medium height have alpine shapes (Anadyrsky, Koryaksky ridges, etc.).

By age, mountains are distinguished between young and ancient. However, one should distinguish between the geological and geomorphological ages of mountains. Geological age is the time of the first formation of a folded structure. Geomorphological age is the time of the last formation of mountainous relief. In nature there are mountains that formed as folded structures in the Caledonian era, but their relief was formed in Quaternary time under the influence of new orogenic movements. Geomorphologically ancient mountains have been subject to destruction for a long time. In relief, they most often appear as peneplains, or outlier mountains. The relief forms of ancient mountains are soft, with gentle slopes.

The slopes in conditions are quite humid climate covered with a thick cloak of deluvial-elluvial formations. The river valleys are well developed. Young mountains have a great height, a highly dissected surface, and a large range of heights. Valleys often have the character of gorges and gorges. They usually develop modern glaciers. The relief of young mountains is characterized by sharp, steep shapes. An example of such mountains is the Caucasus Mountains.

Mountains- strongly dissected parts of land, significantly, by 500 meters or more, elevated above the adjacent plains.

Main sign, by which mountains are classified, is the height of the mountains. So, according to the height of the mountains there are:

Lowlands (low mountains)– mountain heights up to 800 meters above sea level.

Features of low mountains:

The tops of the mountains are round, flat,

· The slopes are gentle, not steep, covered with forest,

· Characteristically, there are river valleys between the mountains.

Examples: Northern Urals, spurs of the Tien Shan, some ridges of Transcaucasia, Khibiny Mountains on the Kola Peninsula, individual mountains of Central Europe.

Medium mountains (medium or mid-altitude mountains)– the height of these mountains is from 800 to 3000 meters above sea level.

Features of the middle mountains: Medium-altitude mountains are characterized by altitudinal zonation, i.e. change of landscape with change in altitude.

Examples of medium mountains: Mountains of the Middle Urals, Polar Urals, mountains of the island of Novaya Zemlya, mountains of Siberia and Far East, mountains of the Apennine and Iberian Peninsulas, Scandinavian mountains in northern Europe, Appalachians in North America, etc.

Highlands (high mountains)– the height of these mountains is more than 3000 meters above sea level. These are young mountains, the relief of which is intensively formed under the influence of external and internal processes.

Features of the highlands:

· Mountain slopes are steep, high,

· The peaks of the mountains are sharp, peak-shaped, and have a specific name - “Carlings”,

The mountain ridges are narrow, jagged,

· Characterized by altitudinal zones from forests at the foot of the mountains to icy deserts on the peaks.

Examples of highlands: Pamir, Tien Shan, Caucasus, Himalayas, Cordillera, Andes, Alps, Karakorum, Rocky Mountains, etc.

Next sign The way mountains are classified is their origin. So, according to the origin of mountains, there are tectonic, volcanic and erosional (denudation):

Tectonic mountains are formed as a result of the collision of moving parts of the earth's crust - lithospheric plates. This collision causes folds to form on the surface of the earth. This is how they arise fold mountains. When interacting with air, water and under the influence of glaciers, the rock layers that form folded mountains lose their plasticity, which leads to the formation of cracks and faults. Currently, folded mountains have been preserved in their original form only in certain parts of the young mountains - the Himalayas, formed during the era of Alpine folding.

With repeated movements of the earth's crust, hardened folds of rock are broken into large blocks, which, under the influence of tectonic forces, rise or fall. This is how they arise fold-block mountains. This type of mountains is typical for old (ancient) mountains. An example is the Altai mountains. The emergence of these mountains occurred during the Baikal and Caledonian eras of mountain building; in the Hercynian and Mesozoic eras they were subject to repeated movements of the earth's crust. The type of folded block mountains was finally adopted during the Alpine folding.

Volcanic mountains formed during volcanic eruptions. They are located, as a rule, along fault lines in the earth's crust or at the boundaries of lithospheric plates.

Volcanic there are mountains two types:

Volcanic cones. These mountains acquired their cone-shaped appearance as a result of the eruption of magma through long cylindrical vents. This type of mountain is widespread throughout the world. These are Fuji in Japan, Mount Mayon in the Philippines, Popocatepetl in Mexico, Misti in Peru, Shasta in California, etc.
Shield volcanoes. Formed by repeated outpouring of lava. They differ from volcanic cones in their asymmetrical shape and small size.

In areas of the globe where active volcanic activity occurs, entire chains of volcanoes can form. The most famous is the chain of Hawaiian Islands of volcanic origin, more than 1600 km long. These islands are the tops of underwater volcanoes, the height of which from the surface ocean floor more than 5500 meters.

Erosion (denudation) mountains.

Erosion mountains arose as a result of the intensive dissection of stratified plains, plateaus and plateaus by flowing waters. Most mountains of this type are characterized by a table shape and the presence of box-shaped and sometimes canyon-type valleys between them. The last type of valley occurs most often when a lava plateau is dismembered.

Examples of erosional (denudation) mountains are the mountains of the Central Siberian Plateau (Vilyuisky, Tungussky, Ilimsky, etc.). Most often, erosion mountains can be found not in the form of separate mountain systems, but within mountain ranges, where they are formed by the dissection of rock layers by mountain rivers.

Mountains occupy about 24% of all land. The most mountains are in Asia - 64%, the least in Africa - 3%. 10% of the world's population lives in the mountains. And it is in the mountains that most rivers on our planet originate.

Characteristics of mountains

By geographical location mountains are united into different communities that must be distinguished.

. Mountain belts- the largest formations, often stretching across several continents. For example, the Alpine-Himalayan belt passes through Europe and Asia or the Andean-Cordilleran belt, stretching through North and South America.
. Mountain system- groups of mountains and ranges similar in structure and age. For example, the Ural Mountains.

. Mountain ranges- a group of mountains stretched in a line (Sangre de Cristo in the USA).

. Mountain groups- also a group of mountains, but not stretched out in a line, but simply located nearby. For example, the Bear Pau Mountains in Montana.

. Single mountains- unrelated to others, often of volcanic origin (Table Mountain in South Africa).

Natural mountain areas

Natural areas in the mountains they are arranged in layers and change depending on the height. At the foothills there is most often a zone of meadows (in the highlands) and forests (in the middle and low mountains). The higher you go, the harsher the climate becomes.

The change of zones is influenced by climate, altitude, mountain topography and their geographical location. For example, the continental mountains do not have a belt of forests. From the base to the summit, the natural areas vary from deserts to grasslands.

Types of mountains

There are several classifications of mountains according to various criteria: structure, shape, origin, age, geographical location. Let's look at the most basic types:

1. By age old and young mountains are distinguished.

Old are called mountain systems whose age is estimated at hundreds of millions of years. Internal processes they have become quiet, and the external ones (wind, water) continue to destroy, gradually comparing them with the plains. The old mountains include the Ural, Scandinavian, and Khibiny mountains (on the Kola Peninsula).

2. Height There are low mountains, middle mountains and high mountains.

Low mountains (up to 800 m) - with rounded or flat tops and gentle slopes. There are many rivers in such mountains. Examples: Northern Urals, Khibiny Mountains, spurs of the Tien Shan.

Average mountains (800-3000 m). They are characterized by a change in landscape depending on the height. These are the Polar Urals, the Appalachians, the mountains of the Far East.

High mountains (over 3000 m). These are mostly young mountains with steep slopes and sharp peaks. Natural areas change from forests to icy deserts. Examples: Pamirs, Caucasus, Andes, Himalayas, Alps, Rocky Mountains.

3. By origin There are volcanic (Fujiyama), tectonic (Altai mountains) and denudation, or erosion (Vilyuisky, Ilimsky).

4. According to the shape of the top mountains can be peak-shaped (Communism Peak, Kazbek), plateau-shaped and table-shaped (Amba in Ethiopia or Monument Valley in the USA), domed (Ayu-Dag, Mashuk).

Climate in the mountains

The mountain climate has a number of characteristic features, which appear with height.

Decrease in temperature - the higher it is, the colder it is. It is no coincidence that the peaks of the highest mountains are covered with glaciers.

Decreases atmospheric pressure. For example, at the top of Everest the pressure is two times lower than at sea level. This is why water boils faster in the mountains - at 86-90ºC.

Intensity increases solar radiation. In the mountains sunlight contains more ultraviolet radiation.

The amount of precipitation is increasing.

High mountain ranges trap precipitation and influence the movement of cyclones. Therefore, the climate on different slopes of the same mountain may differ. On the windward side there is a lot of moisture and sun, on the leeward side it is always dry and cool. A striking example is the Alps, where on one side of the slopes there are subtropics, and on the other, a temperate climate prevails.

The highest mountains in the world

(Click on the picture to enlarge the diagram in full size)

There are seven highest peaks in the world that all climbers dream of conquering. Those who succeed become honorary members of the Seven Peaks Club. These are mountains such as:

. Chomolungma, or Everest (8848 m). Located on the border of Nepal and Tibet. Belongs to the Himalaya mountain system. It has the shape of a triangular pyramid. The first conquest of the mountain took place in 1953.

. Aconcagua(6962 m). This highest mountain V southern hemisphere, located in Argentina. Belongs to the Andes mountain system. The first ascent took place in 1897.

. McKinley- the highest peak in North America (6168 m). Located in Alaska. First conquered in 1913. It was considered the highest point in Russia until Alaska was sold to America.

. Kilimanjaro- the highest point in Africa (5891.8 m). Located in Tanzania. First conquered in 1889. This is the only mountain where all types of Earth's belts are represented.

. Elbrus- the highest peak in Europe and Russia (5642 m). Located in the Caucasus. The first ascent took place in 1829.

. Vinson Massif- the highest mountain in Antarctica (4897 m). Part of the Ellsworth Mountains system. First conquered in 1966.

. Mont Blanc- the highest point in Europe (many attribute Elbrus to Asia). Height - 4810 m. Located on the border of France and Italy, it belongs to the Alps mountain system. The first ascent in 1786, and a century later, in 1886, Theodore Roosevelt conquered the top of Mont Blanc.

. Pyramid of Carstens- the highest mountain in Australia and Oceania (4884 m). Located on an island New Guinea. The first conquest was in 1962.

- (̃Ωραι). Daughters of Zeus and Themis, guarding the gates of heaven, goddesses of the changing seasons. There were three of them: Eunomia, Eirene and Dick. (Source: “A Brief Dictionary of Mythology and Antiquities.” M. Korsch. Saint Petersburg, published by A. S. Suvorin, 1894.) MOUNTAINS... ... Encyclopedia of Mythology

MOUNTAINS- (lat. Horae). Three daughters of Zeus and Themis, goddess of time, order and correctness, beauty and courtesy. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. MOUNTAINS in Greek. mythology of the goddess of the seasons. Dictionary of foreign... ... Dictionary of foreign words of the Russian language

MOUNTAINS- MOUNTAINS, 1) the same as mountainous countries, mountain systems; vast areas of the earth's surface with sharp fluctuations in elevation, significantly elevated above the surrounding plains. They sometimes stretch for several thousand km and have a complex configuration. Consist of... ... Modern encyclopedia

MOUNTAINS- 1) the same as mountainous countries, mountain systems, vast areas of the earth’s surface, elevated several thousand meters above sea level and characterized by sharp fluctuations in altitude. The relief of mountains is formed as a result of complex deformations of the earth’s crust,... ...

MOUNTAINS- part of the earth's surface raised above sea level. m. and adjacent plains, is characterized by significant and often sharp fluctuations in elevation over a short distance. G., bending linearly or arcuately, stretches for tens, hundreds and many... ... Geological encyclopedia

mountains- white-breasted (Wanderer); majestic (Wanderer); high-topped (Gogol); giant mountains (Golen. Kutuzov); densely hairy (Hoffman); dormant (Balmont); drowsy (Shmelev); siliceous (Ryleev, Khomyakov); curly (Wanderer); curly (Wanderer);… … Dictionary of epithets

mountains- Mountains, like lakes, were of great importance to the Celts, being considered cult centers. For example, in the mountainous regions of Gaul, a number of deities associated with mountains and hills were especially revered. The Celtic sky god was also associated with mountains... Celtic mythology. Encyclopedia

MOUNTAINS- see Ory... Big Encyclopedic Dictionary

mountains- Part of the earth's surface, significantly raised above the surrounding plain and forming mountain ranges, chains, massifs, plateaus. → Fig. 219 Syn.: mountainous country... Dictionary of Geography

mountains- a set of closely located individual mountains, mountain ranges, mountain spurs, ridges, highlands, as well as the canyons, valleys, depressions separating them, occupying certain territory, more or less clearly separated from the surrounding plains. By… … Geographical encyclopedia

Books

• Mountains, N. A. Gvozdetsky, Yu N. Golubchikov. The publication "Mountains" provides a comprehensive physical and geographical description of all mountain systems in the world. Provides information about the relief, geological structure, climate, waters, glaciers, permafrost,…