External forces that create relief. Lithosphere and man

Change pretty quickly (a small ravine may appear in a few months), larger forms change slowly, eyelids. There are, however, factors (such as, landslides) capable of channeling: Mountains arise, cutsets, the directions of rivers are changed. In the summer of 2007, one of the similar events occurred: the landslide destroyed the unique geographical education-valley of geysers.

The relief is changed under the influence of two types of factors: exogenous and endogenous. Endogenous (internal) factors: the movement of the earth's crust, volcanic eruptions are considered in detail in the relevant sections. Exogenous factors include: destroying wind and water, heat, animal and vegetable world.

Water has a serious impact on the relief. It blurs the breed, forming a ravine, washing off whole hills, itches the rocks, which can then collapse. The rivers can become more complete and pave a new course, and can be ground, and then the land of sushi remainioned. All this is relief changes. In addition, water interacts with substances of rocks, changing their composition and structure, which can lead to changes to the relief.

The wind acts especially actively where there are no thick pigs of plants. The wind blows fine particles of rocks and brings them to other areas, where they are postponed, lingering with water or plants.

Under the action of heat, many breeds are destroyed. That heating, then cooling back, they are constantly expanding and compressed again. This leads to the destruction of connections between the molecules of the substance, the breeds are cracking.

Plants and animals also affect the formation of relief, one is stronger, others are less. Plant roots destroy dense rocks and at the same time strengthened more loose. Microorganisms change the structure of the soil, which can also lead to a change in relief. Animals are enormous on the relief, which build dams on rivers and streams, in particular - beavers.

The main form of relief

1. Plains - flat or hilly land sushi, having a fairly large area. Plains differ in absolute height (above sea level):
2. Lowlands, height does not exceed 200 m.
3. Hills, height from 200 to 500 m.
4. Plateau, height of more than 500 m.
5. The plateau is a specific form of relief having a flat vertex and rippled edges can reach 3 km.

Plains - more stable areas of the earth's surface, there are less likely to have the plane rivers feeling calmer, the relief varies significantly slower.

The mountains - Lands of sushi, rise to a height of more than 500 m, which have a certain vertex and steep slopes.

Mountains can form ridges and highlands. The ridge is a group of mountains, apparently elongated in a certain direction and having a slight drop of heights. Famous mountain ridges.

\u003e\u003e How and why Russian relief changes

§ 14. How and why the relief of Russia changes

A variety of processes affect the formation of relief. They can be combined into two groups: internal (endogenous) and external (exogenous).

Internal processes. Among them, the greatest impact on the formation of modern relief was rendered by the latest (non-stock) movement of the earth's crust, volcanism and earthquake. Thus, under action internal processes form largest, large and medium forms relief.

Nectonic call the movements of the earth's crust that occurred in it in the last 30 million years. They can be vertical and horizontal. On the formation of the relief, vertical movements as a result of which the earth's crust rise and falls (Fig.20).

Fig. 20. The newest tectonic movements.

The speed and height of the vertical neotectonic movements in some areas were very significant. Most of the modern mountains in Russia exist only due to the latest vertical raising, as even young, relatively recently formed the mountains Course over several million years. Caucasian mountains, despite the destructive effects of external forces, were raised to a height from 4,000 to 6000 m. Urals for 200-600 m, Altai - by 1000-2000 m. The largest plains of Russia also experienced a slight rise - from 100 to 200 m. In The places where the globe went down, the depressions of the seas and lakes arose, many lowlands.

In fig. 20 Determine which types of movements prevail in Russia.

The movements of the earth's crust occur now. The big Caucasian ridge continues to rise at a speed of 8-14 mm per year. Mid-Russian elevation is growing slightly slower - about 6 mm per year. And the territory of Tatarstan and the Vladimir region each year is lowered by 4-8 mm.

Along with the slow movements of the earth's crust in the formation of large and medium-sized relief shapes, an earthquake and volcanism play a certain role.

Earthquakes often lead to significant both vertical and horizontal displacements of rocks of rocks, the occurrence of collaps and failures.

When volcanic eruptions, such specific relief forms are formed as volcanic cones, lava covers and lava plateaus.

External processesForming modern relief related to the activities of the seas, flowing waters, glaciers, VEFA. Under their impact, large and small and small form of relief are destroyed.

At the occurrence of the seas, sedimentary breeds are deposited with horizontal layers. Therefore, many seaside parts of the plains, from which the sea retreated relatively recently, have a flat relief. So the Caspian and North West Siberian lowland were formed.

Fluids (rivers, streams, time aqueous streams) blur the ground surface. As a result of their destructive activity, the form of relief is formed, called erosion. These are river valleys, beams, ravines.

Valley large rivers Have a big width. For example, the Ob Valley in the lower current has a width of 160 km. A little less inferior to her Amur - 150 km and Lena - 120 km. River valleys - the traditional place of the settlement of people, maintaining special types of farming ( livestock breeding on floodplain meadows, gardening).

Raisses - a real trouble for agriculture (Fig. 21). Bringing the fields into small sections, they make it difficult to process. Russia has more than 400 thousand large ravines with a total area of \u200b\u200b500 thousand hectares.

Glacier activities.At a quaternary period, several ancient covering surroundings arose due to climate cooling. In some areas - the centers of glaciation - for the Millennium, ice accumulation was accumulated. In Eurasia, these centers were the Torah of Scandinavia, the Polar Urals, Pouotnian Plateau in the north of the medium-grained plateau and the Mount of Byrranga on the Taimyr Peninsula (Fig. 22).

Along the map of the population in the atlas, compare the population density in the valleys of the largest rivers Siberia and the surrounding territories.

The thickness of the ice in some of them reached 3000 m. Under the action of its own weight, the glacier rained south, for adjacent territories. Where the glacier was passed, the earth's surface changed greatly. In places he smoothed her. In places, on the contrary, dropped down lowering. The ice grinding the rocks, leaving deep scratches on them. Together with ice moved the accumulation of huge stones (boulders), sand, clay, rubble. This mixture of a variety of rocks received the name of Moraine. In the southern, warmer areas, the glacier melted. Moraine, which he carried with him, was postponed in the form of numerous hills, a variety, flat plains.

Wind activity. The wind forms relief mainly in arid areas and where sands are on the surface. Under its influence, dunes, sandy hills and ridges are formed. They are common on Caspian lowland, in the Kaliningrad region (Curonian Spit).

Fig.22. Borders of ancient glaciation

Questions and tasks

1. What processes affect the formation of land relief at present? Describe them.
2. What kind of ice mills are found in your area?
3. What are the relief forms called erosion? Give examples of erosion relief forms in your area.
4. What are the modern relief about the forming processes are typical for your locality?

Geography of Russia: Nature. Population. Economy. 8 cl. : studies. For 8 cl. general education. institutions / V.P. Dronov, I. I. Barinova, V. Ya. Rum, A. A. Lobzhanidze; Ed. V.P. Dronova. - 10th ed., Stereotype. - M.: Drop, 2009. - 271 p. : Il., cards.

Design of lesson Abstract lesson reference frame presentation lesson accelerative methods interactive technologies Practice Tasks and exercises self-test Workshop, trainings, cases, quests Home tasks Discussion issues Rhetorical questions from students Illustrations Audio, video clips and multimedia Photos, pictures, tables, Schemes of humor, jokes, jokes, Comics Proverbs, sayings, crosswords, quotes Supplements Abstracts Articles Chips for Curious Cheat Sheets Textbooks Basic and Additional Globes Other Terms Improving textbooks and lessons Fixing errors in the textbook Updating fragment in the textbook. Innovation elements in the lesson replacing outdated knowledge new Only for teachers Perfect lessons Calendar Plan for the year Methodical recommendations of the discussion program Integrated lessons

From the very beginning of the discussion of the problem of the formation of the globe, precisely the mountains embarrassed scientists. Because if we assume that first the earth was a fiery, molten ball, then its surface after cooling should remain more or less smooth ... well, it may be slightly rough. And where did the high mountain ranges and the deepest depressions in the oceans come from?

In the 19th century, the predominant idea was the idea that from time to time for some reason, a hot magma from within the attack goes to a stone shell and then the mountains are swept away and the ridges rose. Rise? But why then on the surface so many districts, where the ridges go parallel folds one beetroot? In the swelling, each mining area should have the form of the dome or bubble ... to explain the occurrence of folded mountains by the action of the vertical forces coming from the subsoil, failed. Folds demanded horizontal efforts.

Now take an apple in your hand. Let it be a small, slightly tested apple. Scroll it in your hands. See how the skin wrinkled, it was covered with small folds. And imagine that the apple is the size of the ground. Folding will grow and turn into the high mountain ranges ... What power could be so surviving the land so that it covered with folds?

You know that every red-hot body is compressed when cooled. Maybe this mechanism is suitable for explaining the folded mountains on the globe? Imagine - the molten land cooled and covered with a crust. Cork or bark, like a stone dress, turned out to be "stitched" to a certain size. But the planet is cooled further. And it cools, it is compressed. No wonder that over time, the stone shirt turned out to be great, began to swell, go folds.

Such a process suggested to explain the formation of the surface of the Earth, the French scientist Eli de Bomon. He called his contraction hypothesis from the word "contract", which translated from Latin just indicated - compression. One Swiss geologist tried to calculate what the sizes of the globe were, if smooth out all the folded mountains. It turned out a very impressive value. The radius of our planet would increase almost sixty kilometers!

The new hypothesis acquired many supporters. The most famous scientists supported it. They were deepened and developed separate sections, turning the assumption of the French geologist into a single science on the development, movement and deformation of the earth's crust. In 1860, this science, which became the most important section of the complex of the earth science, was offered to be called geotectonic. We will also come further to call this important section as well.

The hypothesis of contracts or compression of the Earth and wrinkling its bark was particularly strengthened when large "heads" opened in the Alps and Appalach. This term geologists indicate gaps in the occurring rocks, when some of them are as if driven to others. Specialists triumphed, the new hypothesis explained everything!

True, a small question arose: why the folds of the folds were located not all over the entire surface of the earth evenly, as on a wrinkled, having fun apple, but were going to the mountain belt? And why did these belts be located only according to certain parallels and meridians? The question is trifling, but cunning. Because the contract hypothesis could not answer him.

The weathering itself does not lead to the formation of relief forms, but only turns solid rocks into loose and prepares the material for moving. The result of such movement is various forms relief.

Effect of gravity

Under the action of the gravity of the breed, destroyed, move along the surface of the earth from the elevated areas to lower. Stone blocks, crushed stone, sand is often rushed down with steep mountain slopes, generating collaps and screaming.

Under the action of gravity arise landslides and villages. They carry huge masses of rocks. The landslides are sliding masses of rocks down the slope. They are formed along the shores of the reservoirs, on the slopes of hills and mountains after heavy rains or melting of snow. The upper loose layer of rocks becomes harder when saturated with water and slides along the lower, non-water layer. Storm rains and rapid melting of snow are also caused in the mountains in the mountains. They are moving down the slope with the devastating force, bringing everything on their path. The landslides and satieces lead to accidents and death of people.

Activity of fluid water

The most important relief converter is moving water that performs greater destructive and creative work. Rivers cut through wide river valleys on the plains, deep canyons and gorges in the mountains. Small water streams create an arms-beef relief on the plains.

Fluid sub statements not only create deepening on the surface, but also capture the fragments of rocks, tolerate them and postpone them in depressions or and their own valleys. So from river nansions along rivers Flat plains are formed

Karst

In those areas where easily soluble rock breeds (limestone, gypsum, chalk, stone salt) occur, are surprising, surprisingly natural phenomena. Rivers and streams, dissolving rock rocks, disappear from the surface and rushed into the depths of the earth's depths. The phenomena associated with the dissolution of rocks with surface and are called karst. The dissolution of rocks leads to the formation of karst forms of relief: caves, abuse, mines, funnels, sometimes filled with water. Beautiful stalactites (multi-meter lime "icicles") and stalagmites ("columns" from limeths) form bizarre sculptures in the caves.

Wind activity

On open unplaced spaces, the wind moves the gigantic clusters of sandy or clay particles, creating the eolone form of relief (Eola God is the patron of wind in ancient Greek mythology). Most of the sandy are covered with sandy hills. Sometimes they reach a height of 100 meters. From above, Barhahan has a kind of sickle.

Moving at high speed, sand particles and rubble handle stone blocks like sandpaper. This process is faster at the surface of the Earth, where the sand is greater.

As a result of wind activity, dense deposits from dust particles can accumulate.
Such homogeneous porous breeds of grayish-yellow colors are called lass.

Glacier activities

Human activity

A large role in changing the relief is played by a man. Especially changed its plain activity. People have long settled on the plains, they build houses and roads, fall asleep the ravines, build a mound. A person changes the relief when mining: digging huge careers, hills are embanked - dumps of empty breed.

The scale of human activity can be comparable to natural processes. For example, rivers produce their valleys, bringing rocks, and a person builds comparable channels.

Relief forms created by man are called anthropogenic. Anthropogenic change of relief occurs with modern technology and quite a quick pace.

Moving water and wind perform a huge devastating work, which is called (from the Latin word Erosio corrosion). Erosion land is a natural process. However, it is enhanced as a result economic activity People: slips of slopes, cutting down forests, non-harmonious grazing of livestock, road gasket. Only over the past hundred years of erosion has undergone a third part of all world-treated lands. The greatest these processes were reached in large agricultural districts of Russia, China and the United States.

Formation of land relief

Features of land relief

The answer was left the guest

As a result of the turbulent development of economic activity, all the increasing impact of a person on relief occurs.

The person began to interfere in the life of the earth's crust, being a powerful relief-forming factor. On the earth's surface there were technogenic form of relief: shafts, recesses, hillocks, careers, pitfalls, mounds, hotcase, etc. There are cases of burning earth crust under large cities and reservoirs, the latter in mountainous areas led to an increase in natural seismicity. Examples of such artificial earthquakes that were caused by filling with water of catlovin large reservoirs, are available in California, USA, on the Industan Peninsula. Such a type of earthquakes was well studied in Tajikistan on the example of the Nucker reservoir. Sometimes earthquakes can be caused by pumping or downloading wastewater with harmful impurities
deep underground, as well as intensive oil and gas production on large
deposses (USA, California, Mexico).

The greatest impact on the earth's surface and subsoil has mountainous
production, especially with the open method of mining. how
already noted above, while the method is withdrawn by significant areas
land, pollution occurs ambient Various
taxicants (especially heavy metals). Local burning of the earth's crust
in the areas of coal mining are known in the Silesian district of Poland, in the UK,
USA, Japan and others. A man geochemically modifies the composition of the earth's crust, mining in
huge number of lead, chrome, manganese, copper, cadmium, molybdenum, etc.

Anthropogenic changes in the earth's surface are also associated with construction
large hydraulic structures. The total impact of the weight of the dam, as well as the leaching processes lead to a significant sediment of their bases to form cracks (at the base of the dam of the Sayan-Shushenskaya HPP, cracks are noted with a length of up to 20 m). Most of the Perm region is 7 mm annually, since the bowl of the Kama reservoir with a huge force presses on the earth's bark. The maximum values \u200b\u200band velocities of the surfactant drawdown caused by the filling of reservoirs are significantly less than in oil and gas production, large groundwater pumping. For comparison, the Japanese cities of Tokyo and Osaka due to pumping
groundwater and seals of loose breeds for last years dropped on 4 m
(at the annual precipitation speed up to 50 cm).

The ecological state of the subsoil is determined primarily by the strength and nature of the impact on them of human activity. In the current period, the scale of anthropogenic impact on earthly subsoil is huge. Only in one year dozens of thousands of mining enterprises of the world are extracted and processed more than 150 billion m. Throat, billions of tons of cubic meters of groundwater are pumped out, the waste mountains accumulate.

A person extracts minerals, as a result of which careers are formed, builds buildings, the channels, makes the mound and fall asleep the ravines. In the process of urbanization, relief of the territory of the territory is subjected to transformations in accordance with the needs of the development of cities.

The impact of a person on relief today also affects the unintentional creation of unwanted surface forms, as well as in direct or indirect effects on natural geomorphological processes, accelerating or slowing them. Thus, in agricultural activities, a person often causes and accelerates the harmful processes, such as water (including irrigation), wind and pasture erosion, secondary salinization, wiping, strengthening thermal circuit processes in polar regions, etc. Especially threatening agriculture on huge areas accelerated water and wind erosion of the soil.

To reduce the degree of manifestation of these processes, it should be opposed to targeted activities.

It has a person influence and endogenous processes. For example, explosive work using huge power charges are accompanied, especially in mountainous areas, artificially caused by moving in the earth's crust (earthquakes) and various races. Depending on the modifications of the forms of the earth's surface occurs (especially in highly developed economic regions and countries) and the root restructuring of the geomorphological foundation of many natural landscapes.

A person can convert the terrestrial surface directly (making a mound, pulling out the pit) or affecting the natural processes of relief formation - accelerating or (less often) slowing them. Relief form created by man are called anthropogenic (from Greek. A'ntro-POS is a man and -Ge'-Nes - cake, born).

Direct impact of man on relief

The man began to interfere with the life of the earth's crust, being a powerful relief formation factor. On the earth's surface there were technogenic form of relief: shafts, recesses, hillocks, careers, pitfalls, mounds, hotcocks, etc. There are cases of incubation of the earth's crust under major cities and reservoirs, the latter in the mountainous areas led to an increase in natural seismicity. Examples of such artificial earthquakes that were caused by filling with water of catlovin large reservoirs, are available in California, USA, on the Industan Peninsula. Such a type of earthquakes was well studied in Tajikistan on the example of the Nucker reservoir. Sometimes earthquakes can be called out or downloading waste waters with harmful impurities deep underground, as well as intensive oil and gas production at large fields (USA, California, Mexico). Self with machines and machines technical means Creates new relief forms: as denudation - careers, shafts, recesses, channels and drainage networks, terraced and cut slopes, reduced hills and small mountains (eg, when developing minerals), surface drawdowns (over mining and when pumping groundwater It is accumulative - embankments, dams, mounds, dumps, hotcases, covered ravines, beams and small valleys or depressions. At the same time, it can artificially direct the activities of natural geomorphological processes to create a convenient relief, for example. Correction of the part of the low-almunicate coasts, creating arts. Lagoon and their filling not only by technical dumping of soil, but also with the help of natural accumulation of nanos in lagoon (Polders in the Netherlands). Mountain production has the greatest impact on the earth's surface and subsoil, especially with the open mining method. As noted above, in this case, significant land areas are withdrawn, environmental pollution by various toxins (especially heavy metals) occurs. Local burning of the earth's crust in the areas of coal mining are known in the Silesian district of Poland, in the UK, in the USA, Japan, etc. Man geochemically changed the land of the earth's crust, mining in a huge amount of lead, chrome, manganese, copper, cadmium, molybdenum, etc.

Anthropogenic changes in the earth's surface are also associated with large hydrotechnical structures. By 1988, more than 360 dams were built all over the world (150 - 300 m high), 37 of them in our country. 37.Summary effects of dams, as well as leaching processes lead to a significant sediment of their bases to form cracks (at the base of the Sayano dam Shushenskaya HPP marked cracks up to 20 m long). Most of the Perm region is 7 mm annually, since the bowl of the Kama reservoir with a huge force presses on the earth's bark. The maximum values \u200b\u200bof the accuracy rate of the earth's surface, caused by the filling of reservoirs, is significantly less than when oil and gas production, large pumping of groundwater.

For comparison, we indicate that the Japanese cities of Tokyo and Osaka due to the pumping of groundwater and sealing loose rocks in recent years dropped by 4 m (at the annual precipitation speed up to 50 cm). Thus, only detailed studies of the relationships of natural and anthropogenic relief processes will help eliminate the unwanted consequences of the impact of man's economic activity on the earth's surface.

Indirect human influence on relief

Previously, it became felt in agricultural areas. Foresting and disintegration of the slopes, especially wrong, topped down, created conditions for the rapid growth of ravines. Construction of buildings and engineering structures, creating additional loads on the slopes, contributes to the occurrence or enhancement of landslides.

Reservoirs are created in natural downstream relief. But water, creating a free surface at the new level, begins the recycling of the banks of the reservoirs. Output erosion, plane flip, landslides are activated. At the same time, the Basis of erosion in the rivers flowing into the reservoir increases, allyuvia accumulates in their rivers. Below the reservoir dam is often enhanced erosion, since the aqueous stream is less loaded by the nanos, a significant part of which is postponed in the standing water reservoir. Less than dozens of years will pass before they come into line with the reservoir and the shape of the slopes of its shores, the new water flow regime and the form of their bed.

An indirect anthropogenic effect on the relief formation is intentional or unplanned change in the conditions of morphogenesis, strengthening or slowing the natural processes of deanitation and accumulation during farms, activities; As a result, reinforced soil erosion occurs, anthropogenic oral formation or acceleration of growth rates in length and depth, changing the relief of the surface of the marshes as a result of their drainage, enhancement of deflation and the revitalization of the dynamics of the accumulative sandy eolog forms of relief due to the non-harmonious grazing of livestock and road Degresses. Specific forms of micro and mesoralfes arise as a result of military management. Action (trenches and trenches, reorganize, shafts, bomb funnels, etc.).

The geomorphological risk is a person (its public, economic and social institutions), carried out on the border of the stability of a natural or natural-anthropogenic geomorphological system. This action (conscious or unconscious) is undertaken in conditions of uncertainty, which in a particular situation leads to one or another risk form. Risk is generated by the presence and feeling of danger - in this case coming from a geomorphological object (geomorphological danger. The risk is associated with the active actions and functioning of the danger entity - humans. In environmental geomorphology, a system of principles of methods for identifying and mapping hazardous geomorphological processes and objects are being developed, forecast Their development, methods of warning, protection and management of dangerous processes in order to reduce the degree and cost of risk.

An unfavorable natural phenomena creating an ecological and geomorphological hazard and bearing catastrophic character, in the mountains are such exogomorphological processes, such as snow avalanches, villages, landslides, ribs, etc. In most, these processes and phenomena are inevitable, difficult to be projected or practically impassable in advance. At the same time, spontaneous destructive processes and phenomena, being in nature natural, often turn out to be technogenic (anthropogenic) predefined. For example, the reduction of forests in the mountains due to the energy crisis over the past 10-15 years was the reason for the intensification of the processes of formation of lands and landslides within the South-Eastern Caucasus. Selene streams - mudigan and mud characteristic of all high-rise belts of this region: high-mountain parts of PP pools. Gondalchary, Jimya, Babachai, Gusarchay. Their foci in the pools r. Gondalchary, Jimya, Ataha, Tuga, Shabranchai, Takhthaderphea is confined to the zones of anthropogenic impact on the geosystems of these regions.

Intensive development of high-mountain meadows, which has been occurring in recent years, leads to a sharp strengthening of fluivinal-glycal and gravitational processes. It is an increase in the lowest frequency snowdowed Lavin, landslide formation, melting and movement of mountain glaciers on the tops of Shahdaha, Basadyuzi, etc. Avalanche processes are observed in the highland and median belts of the Grand Caucasus, where they are confined to steep slopes of the ridges and their vertices (GG. Tufan, Basadyuzi, Shahdag, Gyzylkaya, Babadag). They often occur in large quantities, which cause significant damage to the au pair, putting the mountain roads, bridges, buildings, etc. Engineering and geomorphological structures.

It is known that the northeastern part of the Big Caucasus is a model area of \u200b\u200bintensive development of various types of landslide processes. They are most developed in medium and lowlands, where there is an intensive destruction of the slopes of river valleys, beams, ravines, as well as landslide displacements intensively destroy the slopes of the ridges. The landslides are observed in areas of both wet and with a relatively arid-dry climate and cause great harm to the auxiliary of this region (especially in the Gudialate rivers basins, Hilgilty, Ataha et al.).

In the region under study on the development of landslide and other gravitational and deanitation processes big influence provide intense modern non-stocks and active on modern stage Development of disjunctive dislocations to which the main environmentally hazardous exodine processes are timed. The widespread extension of high-naughty hydroflinal plateau with steep slopes creates favorable conditions for the development of landslide processes. Large landslides - streams are confined to the slopes of such a skill-syncline plateau, like Affordzhinsky, Hezinskoye, Bugo, Gyzykain, Girdagskoye, etc. (Budagov, 1977).

Currently, such a question is set - the management of risk generated by dangerous natural and technogenic phenomena (Seliversts, 1994; Grigoriev, Kondratyev, 1998, etc.). Environmentally dangerous phenomena, as a rule, arise suddenly. Studies of their emergence and development, conducted recently within the eastern part of the Greater Caucasus, allowed to identify some important factors - indicators that allow you to predict the further course of the development of these processes. They are connected not so much with natural or anthropogenic factors as with their simultaneous influence and activities of the population in places subject to these phenomena.

In our opinion, to predict the development of exogenous processes in order to track modern fluctuations in areas of their distribution in such hard-to-reach mountain regions, as a large Caucasus, remote sensing methods are most effective. They increase the objectivity of the geographical forecast, improve the quality of the material obtained for detailed analysis, allowing to judge the nature and strength of exogenous processes in the near future.

Man and terrestrial surface relief have a comprehensive impact on each other. Since ancient times, the relief determined different kinds Human activity, the nature of settlements, migrations depended on it. Currently, despite the technical progress, the relief continues to have a different impact on man and its activities. The features of the laying and construction of various engineering structures, mining of minerals depend on the relief and geological structure of the territory. The environmental role of modern relief and relief-forming processes is large. For example, the distribution and migration of pollutants is associated with the relief. Great importance Have dangerous and unfavorable geomorphological processes. Some of which cause significant harm to human and objects of its economic activity.

It is necessary to pay attention to the other side of the question - an anthropogenic factor in relief formation.

A person can convert the terrestrial surface directly (making a mound, pulling out the pit) or affecting the natural processes of relief formation - accelerating or (less often) slowing them. Relief forms created by man are called anthropogenic.

The direct impact of a person on the relief is mostly manifested in the areas of mineral development. Underground mining is accompanied by a removal of the surface large number Empty breed and the formation of dumps that usually have a conical shape - tercosov (Lat.; literally - earth cones). Numerous groundcons create a characteristic landscape of coal mining areas.

With open mining of minerals, it is possible to first create significant dumps of opening - rocks that occur above the layer, which contains minerals; The development of the productive layer is by digging extensive slides - careersThe relief of which is very complex, it is determined by the geological structure (plots with a minor content of minerals can remain intact), the need to protect the walls of the career from the collapse, create a relief, convenient for the entrance of the transport (Fig. 59).

Significant changes in relief are produced during transport, industrial and civil construction. The facilities are leveling platforms, mounds and excavations are created for roads.

Agriculture has a direct impact on the relief predominantly in the mountainous areas of the tropics. The terracement of the slopes to create horizontal sites is widespread here.

The indirect influence of a person on the relief has previously become felt in agricultural areas. Foresting and disintegration of the slopes, especially wrong, topped down, created conditions for the rapid growth of ravines. Construction of buildings and engineering structures, creating additional loads on the slopes, contributes to the occurrence or enhancement of landslides.

In the areas of underground mining, extensive soil drawders may be observed, as collaborated in the workers and galleys.

Reservoirs are created in natural downstream relief. But water, creating a free surface at the new level, begins the recycling of the banks of the reservoirs. Output erosion, plane flip, landslides are activated. At the same time, the Basis of erosion in the rivers flowing into the reservoir increases, allyuvia accumulates in their rivers. Below the reservoir dam is often enhanced erosion, since the aqueous stream is less loaded by the nanos, a significant part of which is postponed in the standing water reservoir.

Less than dozens of years will pass before they come into line with the reservoir and the shape of the slopes of its shores, the new water flow regime and the form of their bed.

The impact of man is experiencing not only exogenous, but also endogenous processes. Large reservoirs are a mass of water with colossal weight: each cubic kilometer of water has a weight of 1 billion tons, and, for example, a fraternal reservoir contains more than 169 km3 water. Under the severity of water, the earth's bark begins, and the probability of earthquakes increases in seismic districts.

The geomorphological risk is a person (its public, economic and social institutions), carried out on the border of the stability of a natural or natural-anthropogenic geomorphological system. This action (conscious or unconscious) is undertaken in conditions of uncertainty, which in a particular situation leads to one or another risk form. Risk is generated by the presence and feeling of danger - in this case coming from a geomorphological object (geomorphological danger. The risk is associated with the active actions and functioning of the danger entity - humans. In environmental geomorphology, a system of principles of methods for identifying and mapping hazardous geomorphological processes and objects are being developed, forecast Their development, methods of warning, protection and management of dangerous processes in order to reduce the degree and cost of risk.

PrevNext

See more:

Slides and text of this presentation

Slide 1.

Development of relief form Teacher Geography: Kildashova O.V.

Slide 2.

Objectives:
Introduce students with the influence of external and internal factors on the formation of relief. Show continuity relief development. Consider the types of natural phenomena, causes. Talk about the influence of a person on the relief of the lesson: 1. Organizational moment. Greeting. Message themes and objectives of the lesson.4. Record the topic of the lesson in the notebook.5. Work on a new topic. Check homework: Let's remember the definition of minerals and how are they classified? What are the mineral resource bases?

Slide 3.

The relief is constantly changing under the action of exogenous (external) and endogenous (internal) factors. Let's draw a scheme in notebooks with explanations:
Relief
Endogenous (internal factors)
Exogenous (external factors)

Slide 4.

Endogenous processes are called non-stock or newest. (They can manifest themselves in the mountains and on the plains).
Endogenous factory on folded areas on platforms (occurrence of mountains, mountains - volcanoes, rabes, horses, intergraded)

Slide 5.

In the mountains, the most active movements of the earth's crust. In the Caucasus, movements occur at a speed of 5 - 8 cm per year, in the young mountains, where the globe is plastic, movements are accompanied by the formation of folds. On the platforms the latest movements are manifested in the age-old slow oscillations of the earth's crust, some areas are slowly raised, and others are lowered, the speed is about 1 cm per year.

Slide 6.

Exogenous processes are processes occurring under the influence of fluid (rivers, glaciers and villages), permafrost and wind

Slide 7.

Exogenous processes are processes occurring under the influence of flowing water (rivers, glaciers and villages), permafrost and wind.
Exogenous factors
Olyonenianenim, Zandrovy Plains, Baranja Libi, Lakes.
fluid wary valleys, ravines, hollows.
Veteroolem molds (vegans, dunes).
human

Slide 8.

Man is also a powerful relief force. With mining, huge careers are formed. Dumps of the empty breed talk about the useful mining of minerals - it is an area. Careers and groundcocks create (lunar) career landscape. Louds are built roads, dams, tunnels, and other economic objects that change the relief and leading often to the formation of landslides, collaps and other natural phenomena in the lithosphere are earthquakes and volcanism, sat (mud streams), collaps. Consider natural phenomena, write to the definition notebook.

Slide 9.

Earthquakes are a manifestation of the latest tectonic movements of the earth's crust.

Slide 10.

The villages are mud streams carrying with a huge speed from the mountains, have great devastating consequences.

Slide 11.

The landslides are the displacement of the masses of rocks down the slope under the action of gravity

Slide 12.

Fixing the material studied:
What factors affect the relief changes? What form of relief form endogenous processes? What processes are attributed to exogenous factors? What is the setels, landslides, earthquake?

Slide 13.

Homework:
§ 8 p.49-56

Such plains are characterized by a complex relief, the forms of which were formed during the destruction of heights and transitioning materials of their destruction. The nature of the relief of the surface of the Earth is closely associated with these tectonic structures, and with the composition of rocks that form them.

The activities of human society for many millennia its existence had a huge impact on the development of natural geological and relief-forming processes. In the second case, anthropogenic-determined relief occurs.

For the first time, anthropogenic form of relief originated when the hunting tribes began to dig a pits for catching animals, the cave pt. There are intermediate forms A. R.- Harmful, but inevitable: careers, groundcone, etc. A. P. It is the component of anthropogenic, or cultural, landscape.

The surface lowering is noted at 10-18 m with a diameter of several kilometers. The anthropogenic formations of the relief include here the channels of the channels and the ditches deployed during irrigation and land reclamation. Issues of study I. proper regulation The processes caused by the human production activities are paying great attention in our country.

As already noted above, as a result of diverse economic activities, anthropogenic deposits arise. This term is investing the concept of the genesis of deposits, in contrast to the age concept of "anthropogenic", i.e. quaternary deposits. As complexes are allocated deposition of bulk, worn, artificial reservoirs, artificially created and artificially transformed in natural occurrence.

Anthropogenic relief forms

And from that moment on, an important role in the transformation of the face of the Earth plays the activity of man, which, sometimes, leads to unexpected results. The relief is also unequal - these are different morphostructures. The plain territories of different types with small amplitudes of the relief are characteristic of platforms. On large spaces, the same layers of rocks are taken offen, and this causes the appearance of a homogeneous relief.

On the plains, endogenous processes are manifested in the form of weak vertical tectonic motion. A variety of their relief is associated with surface processes. The relief of mountain countries meets orogenic belts. Different types of mountain relief depend on rocks that make them up, from the height of the mountains, from the modern features of the nature of the area and from geological history.

The mountains arose in such places of the earth's surface, which were subjected to intense tectonic raising. There are 2 weathered forms: the chemical, at which the mechanical is decomposed, at which it crumbs into pieces. As a result of cooling, deep in the depths of the Earth, molten magma, volcanic rocks are formed.

Often in rocks meet multi-layer horizontal simplifies and cracks. Over time, they rise to the surface of the Earth, where pressure is much lower. The stone is expanding as pressure decreases, and everything is cracked in it, respectively. For example, water that frozen in a crack expands, spreading its edges.

This process is called frosty crushing.

Water, flowing across the surface or absorbed into the rock, lines chemicals into it. For example, water oxygen enters the reaction with iron, which is contained in the breed. River erosion is a combination of chemical and mechanical processes. Water not only moves rocks, and even huge boulders, but, as we have seen, dissolves their chemical components.

Formation of land relief

Sea (about what kind of sea can read in this article) constantly and tirelessly worries over the alteration of the coastline. In some places, something is increasing, and in others - something cuts. Gravity with landslides makes sliding down the slope of solid rocks, changing the terrain. As a result of weathelation, fragments of rocks are formed, which constitute the bulk of the mass of the landslide. Moving landslides sometimes slowly, but sometimes, they rush at a speed of 100 m / s and more.

As a result of the gathering of avalante (stone, snow or those and others), similar disasters occur. A large landslide can lead to significant relief changes.

Also-old climatic oscillations also led to significant changes in the earth relief. In ice polar hats, during the last glacial periodThere were huge masses of water. Northern cap extended far to the south North America and the European continent.

The glacier, as it moves, captures, in the so-called accumulation area, a plurality of rocky fragments. There are not only stones, but also water in the form of snow, which turns into ice and forms the body of the glacier. By passing the border of the snow cover on the slope of the mountain, the glacier shifts into the ablation zone, that is, gradually melting and blur.

The place in which the glacier finally melts and turns into a conventional river, is often denoted by the final moraine. Those places that have completed their existence have long disappeared glaciers can be found in such a Morane. The main line of the ice flow falls out of the side valley, which is laid.

Internal (endogenous) is the processes inside the Earth, in the mantle, the core, which manifest themselves on the surface of the Earth as destructive and creative. In mining countries with a complex relief, individual ridges, mountain arrays and different intermediate decreases are distinguished. Processes on the earth's surface, which affect the main form of relief formed by internal, that is, endogenous processes, are also closely related to geological structures.

Another interesting thing:

Impact of man on relief and geological processes

The modern impact of a person on the relief is very diverse and covers more than 70% of sushi.

It is manifested mainly in the deliberate creation of artificial form of relief as a result of economic activities. For example: when developing minerals - mines, careers, mining, dumps, embankments; in industry - landfills, artificial sumps of wastewater, etc.; In agriculture - terracing of the slopes, irrigation and drying channels, ponds and reservoirs, etc. The person fundamentally modifies those or other form of relief, which ultimately leads to the formation of anthropogenic landscapes, which in many areas prevail over natural.

The impact of a person on the relief affects the unintentional creation of various, as a rule, unwanted surface forms, as well as in direct or indirect effects on natural geomorphological processes, accelerating or slowing them. For example, in agricultural activities, a person often causes and accelerates harmful processes, such as water (including irrigation), wind and pasture erosion, secondary salinization, wiping, strengthening thermal processes in polar regions, etc. Especially threatening agriculture on huge areas Accelerated water and wind erosion of the soil. To reduce the degree of manifestation of these processes, they must be opposed to targeted activities - technical amelioration.

A person affects both endogenous processes. For example, explosive work using huge power charges are accompanied mainly in mountainous areas, artificially caused by moving in the earth's crust (earthquakes), creating various shaped and sizes. Depending on the modifications of the forms of the earth's surface (especially in highly developed countries), a root restructuring of the geomorphological basis of many natural landscapes occurs.

Concept of atmosphere, weather and climate

Atmosphere (from Greek aTMOS - Par I. sphaira - Ball) - the air outer sheath of the Earth, associated with the power of gravity. The composition, structure and physical processes of the atmosphere serve as a subject of study of meteorology. Conditionally, the height of 3000 km is accepted for the upper limit of the atmosphere. Pure and dry air at sea level is a mechanical mixture of gases: nitrogen - 78.09%, oxygen - 20.95, argon - 0.93, carbon dioxide - 0.03%. The content of other gases (helium, escort, hydrogen, ozone, etc.) is very small - less than 0.1%. There is a water vapor in the atmosphere, the amount of which changes both in space and in time. A "ozone screen" plays a major role in the development of land landscapes, which absorbs a significant part of ultraviolet radiation. Carbon dioxide content (CO2) in the atmosphere is small. True, its amount increased over the past hundred years from 0.29 to 0.33%.

In addition to gases, water vapor, aerosol impurities (dust, smoke, microorganisms) are present in the atmosphere, serving the condensation cores needed to form clouds and fogs. By the nature of the temperature change, the atmosphere is divided into the troposphere, the stratosphere, the mesosphere, thermosphere and the exosphere. The spheres are separated by transition layers - pauses. The most active layer is the troposphere. It occurs in the mixing of air, the formation of clouds, precipitation and other physical processes and phenomena. The troposphere is in continuous interaction with other spheres of geographic shell and constantly experiencing the influence of the Sun. The value of the atmosphere for the formation of landscapes is huge. It not only absorbs the destructive for all living ultraviolet radiation of the Sun, but also creates favorable thermal conditions - the climates of the Earth.

The state of the atmosphere in a particular area of \u200b\u200bthe earth's surface is expressed weatherman and climate.

The physical condition of the atmosphere of the area at a certain point in time is called weatherman. It is characterized by a complex of meteorological elements and phenomena: air temperature, humidity, pressure, wind, cloudiness, precipitation, etc. It represents the external manifestation of radiation and circulation conditions, the effect on them of the underlying surface.

Climate -statistical mode of atmospheric conditions (weather conditions), characteristic of each place of the land. the main role In climate formation belongs solar radiation - The source of origin of all atmospheric processes.

The effect of an inhomogeneous landscape surface complicates the circulation of the atmosphere, increases the variety of climates on the globe. There are several climate classifications distinguished by one or several leading features, conditions of origin. In generalized form on the globe number seven climatic belts: Equatorial, subequatorial, tropical, subtropical, moderate, subogenous and polar. They allocate the corresponding climate zones characterized by their characteristics of the weather. For example, among the climates of a moderate belt distinguish between continental, moderate, ocean moderate, etc.

The daily and annual temperature of the air temperature in the surface layer affect the latitude of the locality, the nature of the underlying surface and its physical properties.

The atmosphere puts pressure on the earth's surface. A very complex pressure distribution is observed on the earth's surface, determined using the isobar (lines connecting points with the same pressure). The system of closed isobar with reduced pressure in the center is called cyclone and with high pressure in the center - anticyclone.

The main reason for changing the pressure is the movement of air, its outflow from one place and the influx to another. This movement is associated with the different character of the underlying surface, its various heating.

Important weather and climate characteristics - precipitation,dropping in the form of rain, snow, hail, cereals, morosi. The amount of them is measured by the thickness of the water layer in mm, and the character depends on the conditions of education.

Climate and landscape

The climate affects the formation of the appearance of the landscape, depending on his belonging to one or another climatic region. In addition, it directly affects directly or indirectly on the landscape resource, many geomorphological, geochemical, biophysical and other processes occurring inside the landscape and determining its dynamics. The impact of the climate on the landscape is manifested in three directions: global, zonal and provincial.

The processes of moisture and heat exchange between the ocean and land are determined macroclimat Continents and planets in general. Climatic factors determine the system of natural (landscaped) zones on the earth's surface. The degree of participation of one or another component of the landscape in the formation zonal climate (mesoclimate) Depends on the type of landscape. In the literature, it is often possible to meet expressions: steppe, taiga, deserted and other climates, characterized by the devices due to the zonal features of landscapes.

Inside a specific area of \u200b\u200bthe landscape is formed microclimate.It is interpreted as weather mode of a small area of \u200b\u200bthe landscape - facies, for which a homogeneous underlying surface is characteristic. Microclimate, depending on the size of the foundations, covers the area from several tens of square meters to several square kilometers.

A person has a huge impact on the macro, meso and microclimate. For example: cutting down forests, construction of giant enterprises, burning fossil fuels, the disintegration of huge areas lead to a change in the balance of solar radiation and the chemical composition of the atmosphere.

The following modern changes in landscapes are the greatest impact on the climate: the growth of urban and urban areas, the construction of artificial reservoirs, the creation of anthropogenic agricultural landscapes, pollution of the oceans. Ocean pollution disrupts heat, moisture and gas exchange between the atmosphere, oceans and continents. Moreover, all these changes often have consequences that are difficult to anticipate, since the system of direct and inverse ties in the atmosphere is so complex.