Geography relief and minerals. Relief and minerals

Studying the relief South America in the 7th grade, so many have most likely heard about the Andes, Patagonia, the Amazonian lowland, etc. Perhaps our article will be of interest not only to school students, but also to those who want to refresh their knowledge about a distant continent. In it we will talk about the main landforms of South America.

Geography of the mainland

On the map, the continent is below North America connected to it by the narrow Isthmus of Panama. Most of it is in the Southern and Western Hemispheres. Its shores are washed by the waters of the Atlantic and Pacific oceans.

The area of ​​South America is the fourth in the world and occupies 17,840,000 km2. 390 million people live on its territory, there are 12 independent and 3 dependent states. The largest of them: Brazil, Argentina, Bolivia, Colombia and Peru. All of them, except French Guiana, belong to the countries Latin America. A huge, though not always positive, role in their development was played by colonists from Spain, France and Portugal.

Landforms on the mainland of South America are very diverse and represent both high mountains, so mid-altitude plateaus and lowlands. From north to south, the continent stretches for 7350 kilometers, covering six climatic zones - from the northern subequatorial to the southern temperate. For the most part, the conditions are hot and very humid, and the temperature does not drop below +5 °C.

The peculiar climate and topography of South America have made it a champion in some areas. So, on the continent is the highest volcano, the world's largest river and the highest waterfall. And due to the large amount of precipitation, the mainland is the wettest on the planet.

Relief of South America

South America was once part of the Gondwana continent along with Antarctica, Australia and Africa. After their separation from each other, it briefly turned into a huge island, until the Isthmus of Panama arose.

The landforms located on the mainland of South America divide it into two large areas: flat-mountainous in the east and mountainous in the west. The average height of the entire territory of the continent is approximately 600 meters.

At the heart of the eastern part of South America is an ancient platform, so the local landscapes are mostly flat. They are represented by the Amazonian, Orinoco and La Plata lowlands, the Patagonian plateau, the Brazilian and Guiana plateaus. In the extreme southeast is the Salinas-Chicas depression - the lowest point on the continent with a height of -42 meters.

To the west are the Andes mountains. These are young geological formations formed during relatively recent (about 50 million years ago) volcanic activity. However, the process of their formation is not over, so volcanic eruptions and earthquakes can be observed now.

uplands

In the relief of South America, there are several elevated areas called highlands and plateaus. One such area (the Central Andean Highlands) is located right in the middle of the Andes. Here, the volcanic plateaus are interspersed with flat flat areas, and the average heights reach 4000 meters.

Landforms in the east are much lower. There is located the vast Brazilian Highlands, covering about 5 million km 2. Its highest point is Mount Bandeira (2890 m), although in most of the territory it rises to a height of 200 to 900 meters. The highlands are flat areas with separate ledges of mountain ranges and plateaus with very steep, almost vertical slopes. Similar is the small Guiana Plateau in the north, which by origin is part of the Brazilian.

lowlands

The low-lying plains cover a significant part of the mainland, and occupy the territory between the mountains and plateaus of South America. They are located in the places of deflections of the foundation platform, which creates excellent conditions for the formation of swamps and rivers with deep valleys (Amazons, La Plata, Orinoco, Parana).

The Amazonian lowland is the largest on the continent and on the entire planet. It stretched in the north of the continent from the foot of the Andes to the coast Atlantic Ocean. In the southeast, it is framed by the Brazilian Plateau.

The area of ​​the Amazonian lowland is 5 million km 2. Here flows the largest river on Earth, the Amazon, along with numerous tributaries. In the west, the relief of the lowland is flat and even; in the east, it is indented by crystalline rocks that come to the surface. The rivers in the eastern part of the Amazon are not as muddy as in the western part, dotted with numerous rapids.

Huge areas of the lowland are swampy and covered with impenetrable jungles of moist equatorial forests. This is one of the least studied regions of the world, inhabited by anacondas, caimans, cougars, tapirs, armadillos, capybaras, maze deer and other unique inhabitants.

Andean Cordillera

By origin, the Andes are part of the North American Cordillera. They run along the entire western coast of the continent, across the territory of seven states, and are the longest mountain system in the world (9,000 km). This is the main watershed of the mainland, in which the Amazon River originates, as well as tributaries of the Orinoco, Paraguay, Parana, etc.

The Andes is the second highest mountain system. Its highest point is Mount Aconcagua in Argentina (6960.8 m). By relief and others natural features distinguish between the Northern, Central and Southern Andes. In general, mountains consist of numerous meridional ridges parallel to each other, between which there are depressions, plateaus or plateaus. On some massifs there are permanent snows and glaciers.

Islands and coasts

In the north, the outlines of the mainland are mostly simple, coastline not much cut. It does not form bays deeply protruding into the land and peninsulas strongly elongated into the sea. The shores are mostly smooth, and only in the Venezuelan region there is an accumulation of small islands.

To the south, the situation is changing. The mainland gradually narrows, and its shores are dotted with bays, bays and lagoons. Along the coast of Chile and Argentina, many islands adjoin South America. Only in the composition of the Tierra del Fuego archipelago there are more than 40 thousand of them.

Not all of them are inhabited, for example, the Falkland Islands. But many have fjords, glacier-covered mountains, gorges and a huge variety of animals. That is why most of the southern coastal areas are included in national parks and are even protected by UNESCO.

Minerals

Geological structure and the diversity of the relief of South America were reflected in its natural resources. The continent is especially rich in minerals; at least half of the periodic table can be found in its bowels.

The Andes mountain ranges contain iron, silver, copper, tin, polymetallic ores, as well as antimony, lead, gold, saltpeter, iodine, platinum and precious stones. Colombia is considered the leader in the extraction of emeralds, Chile occupies the first world positions in the extraction of copper and molybdenum, Bolivia is famous for its tin reserves.

The troughs surrounding the Andes contain deposits of oil, coal and natural gas. Oil is also rich in the ocean floor near the mainland and the vast plains in the east. In the Amazonian lowland alone, proven oil reserves are about 9,000 million tons.

A powerful source of minerals is the Brazilian Highlands, located entirely in Brazil. On the territory of the country there are large deposits of diamonds, zirconium, tantalum, mica, tungsten, is the world leader in the extraction of niobium.

On the territory of Argentina - the second largest country on the continent, there are deposits of marble, granite, sulfur, brown coal, beryllium, uranium, tungsten, copper, natural gas and oil.

Conclusion

The relief of South America combines ancient geological formations and very young and active forms. Due to this, the landscapes of the continent are represented by mountains and volcanoes, plateaus and plateaus, lowlands and depressions. There are glaciers, fjords, deep river valleys, high waterfalls, canyons and gorges. Such a variety of relief was also reflected in the nature of the continent, making many of its objects a real treasure of the planet.

It's all the bumps earth's surface, which is formed due to the interaction of internal and external forces Earth.

Landforms are distinguished by size, structure, origin, etc. There are convex (positive) and concave (negative) relief forms.

This diversity is primarily due to large sizes territory and the complex geological history of this territory. The largest plains: East European (Russian),. They are located on and have a two-tiered structure. The West Siberian Plain is located on the West Siberian Plate. It is often called the lowland, because. half of its territory has a height of less than 100 meters and only at the edges of its height reaches 150 - 200 m.

Divide East European and West Siberian Plain, low mountains (the highest peak of these mountains is Mount Narodnaya 1895 m). These are ancient, strongly destroyed and slightly renewed in the Neogene folded-block mountains.

Of great importance in western Yakutia, potash and table salts in, mica in Eastern Siberia, as well as graphite in the Urals, Eastern Siberia and the Far East.

The country has significant reserves of peat, oil shale, building sands, limestone, chalk and gypsum.
According to the reserves of many minerals Russian Federation occupies leading positions in the world, so 1st place in terms of reserves and iron ore, 3rd place in explored coal reserves, etc. and develops its economy almost entirely on its own mineral resources. Despite this, it must be remembered that the minerals accumulated over the long history of the Earth's development are exhaustible and non-renewable. Their careful, rational use is necessary. To do this, new technologies are being developed that ensure minimal losses during mining and processing, it is necessary to extract from the ore as much as possible all the useful components that are in it. In addition, the search and development of new deposits.

Minerals are valuable formations that occur inside and partially above the earth's crust, their physical and Chemical properties, as well as the composition are valued for the possibility of using in various spheres of human life. Fossils can be both solid and liquid, and gaseous.

Accumulations of fossil resources are called deposits - in these zones they are presented in large quantities in the form of placers, veins, layers, stocks. Russian PI is a colossal set of valuable metals, ores, combustible materials and others. Many of them are concentrated on the territory of the Russian Federation in greater numbers than anywhere else.

general information

Russia, having the most large area in comparison with other countries, it occupies a leading position in the extraction of the most important minerals. The total number of deposits is more than 200,000, and this number is constantly increasing as methods for finding new deposits are improved. The cost of the estimated resources is more than 30 trillion. dollars. The amount of natural gas and coal beats the records of most other countries: they represent 32% and 30%, respectively, of the total world reserves.

Relation between relief and minerals of the Russian Federation

The territory of Russia is extremely complex and diverse due to its large extent from west to east and from south to north. Huge territories unite different terrain, rich in the full spectrum of PI:

• in the European and central region;
• mountains in the south, east and northeast, as well as a unique Ural Range, crossing the country;
• northern slope with waters flowing into the seas of the Arctic Ocean.

”, “minerals”. They are considered in the physical and geographical characteristics of any region.

Definition 1

Geological structure - this is the structure of the site earth's crust, features of the occurrence of rock layers, their mineralogical composition, origin.

When studying the geological structure of the continents, the concepts of "platform", "folded area" are encountered.

Definition 2

Platform is a large, relatively immobile area of ​​the earth's crust.

Platforms underlie every continent. In the relief, the platforms correspond to plains.

Definition 3

Fold area - a mobile section of the earth's crust, where active mountain-building processes (earthquakes, volcanic eruptions) take place.

In the relief, folded areas are represented by mountain systems.

Definition 4

Relief is a set of irregularities in the earth's surface.

Definition 5

Minerals - this is the wealth of the earth's interior, which can be used by man to meet his needs.

Ready-made works on a similar topic

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• abstract Geological structure and relief of Africa 260 rub.
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Features of the geological structure of Africa

About $180 million years ago, the territory of Africa was integral part ancient supercontinent Gondwana. When Gondwana split, the African lithospheric plate separated. At the heart of the modern territory of Africa lies a part of this plate, namely the ancient (Precambrian) African-Arabian platform .

In most of the territory, active mountain building stopped as early as $1000 - $500 million years ago. Later, the rigid core of the mainland did not experience folded processes.

The lower part of the platform, that is, its foundation, is made up of crystalline rocks - basalts and granites having igneous and metamorphic origin. They are very ancient in age. Due to weathering, continental sedimentary deposits accumulated on the basement, and marine sedimentary deposits accumulated in depressions. Over millions of years, they formed a powerful sedimentary cover on the platform. It should be noted that the sedimentary cover covers the foundation unevenly, because the platform experienced several slow ups and downs over a long period of time. In those areas where a long process of uplift took place, the ancient crystalline rocks of the basement appeared on the surface, thus forming shields.

Definition 6

The shield is the place where the crystalline foundation of the platform comes out to the surface.

On other parts of the platform, the processes of subsidence and flooding by the waters of the ancient seas took place. In these places, the foundation was covered by a huge thickness of marine sedimentary deposits, and slabs formed in such areas of the platform. Millions of years later, the platform in its northwestern and southern parts was “completed” with parts of the ocean floor, while its sedimentary rocks were crumpled into folds and formed folded areas (area Atlas and Cape mountains ). More than $60 million years ago, the African-Arabian platform began to rise intensively. This rise was accompanied by giant faults in the earth's crust. During these faults, the largest system on land was formed East African faults (rifts) . It stretches for $4,000$ km from the Isthmus of Suez along the bottom of the Red Sea and overland to the Zambezi River. The width of the rifts in some places reaches up to $120$ km. The above faults, like a knife, cut through the African-Arabian platform. Along them there are earthquakes, manifestations of volcanism.

Relief of Africa

The relief of Africa is dominated by flat areas. This is due to the fact that almost the entire continent is based on a platform. A feature of the African plains is the predominance of high plains:

• hills,
• plateau,
• plateaus.

This can be explained by the general uplift of the entire territory of Africa in the Cenozoic. The lowlands extend only in narrow strips, mainly along the sea coasts.

The largest plains are located in the northern and western parts mainland. Their surface is very heterogeneous. At the same time, the alternation of highlands with lowlands and plateaus is characteristic of Africa. In places where the crystalline rocks of the foundation rise to the surface, Ahaggar and Tibesti highlands , with a height of more than $3000$ m. Among the high plateaus (up to $1000$ m) lies the marshy depression of the Congo. The Kalahari Basin is also surrounded on all sides by plateaus and plateaus.

A relatively small area in Africa is occupied by mountains. Has the highest scores East African plateau . On it are extinct volcanoes Kenya ($5199$ m) and kilimanjaro ($5895$ m) is the highest point in Africa.

These volcanic mountains are confined to the East African Rift Zone. Ethiopian highlands with numerous extinct volcanoes, it is uplifted by $2,000-3,000 m. In the northwestern part of the mainland rise atlas mountains (or the Atlas Mountains), formed at the junction of two lithospheric plates, in a place where the earth's crust was crumpled into folds. In the south of the mainland, low and flat-topped cape mountains . They look like cups turned upside down (hence the name). dragon mountains - higher, from the coast in giant ledges they descend to the hinterland of the mainland.

Minerals

The bowels of Africa are rich in a variety of minerals, their placement is closely related to the geological structure of the mainland. Deposits of ore minerals are confined to the ancient foundation of the platform. In particular, this applies to gold and ores such as:

• iron,
• copper,
• zinc,
• tin,
• chrome.

The largest deposits are concentrated in the south and east of Africa, in places where the basement is shallow. In particular, there are significant deposits gold and copper , in terms of the number of their reserves, Africa ranks first and second in the world, respectively. The bowels of the mainland are rich and uranium ores . Africa is famous for its deposits diamonds - Valuable gems.

Remark 1

They are used not only for the manufacture of expensive and exquisite jewelry, but also as materials unsurpassed in their hardness. Half of the world's diamonds are mined in Africa.

Their deposits are found on the southwestern coast and in the center of the mainland. Deposits of non-metallic minerals occur in sedimentary rocks, which cover the low areas of the platform with a thick cover. Such breeds in Africa include:

• coal,
• natural gas,
• oil,
• phosphorites and others.

There are huge deposits in the north of the Sahara and on the shelf of the Gulf of Guinea. The developed deposits of phosphorites, widely used in the production of fertilizers, are located in the north of the mainland. There are also ore minerals in the sedimentary strata, which were formed as a result of weathering processes of igneous and metamorphic rocks. For example, in southern and western regions Africa known deposits iron, copper, manganese ores and gold that are of sedimentary origin.

On the East European Plain, where the Leningrad region is located, mountain-building processes ended in the most ancient geological eras. Such areas of the earth's crust are called platforms. The basis for the East European Plain is the Russian platform, the foundation of which is composed of ancient crystalline rocks– diabases, gneisses, granites, diorites. Northwest of the Priozersk-Vyborg line, these crystalline rocks come to the surface. To the south, on crystalline rocks, lies a stratum of sedimentary rocks deposited in the seas that covered this territory for many millions of years. In the south and east of the region, the foundation is located at a considerable depth (800-1000 m). Sedimentary rocks on the territory of our region are represented by blue clays of the Cambrian age, occurring on granites; above are sands and sandstones, then limestones, as well as marls and dolomites of the Ordovician, Devonian and Carboniferous periods (it should be noted that this, of course, is only a simplified diagram of the geological structure).

A new period in sedimentation and relief formation in our region is associated with the activity of continental ice and melt waters during the ice age, and later with the activity of the sea, flowing waters, wind, and also people. The region has experienced several ice ages, which alternated with interglacial epochs. The last glaciation ended only 12 thousand years ago. The thickness of the glacier reached 2 km; ice with such a mass acquires the properties of plasticity, i.e. begins to flow, moving masses of loose material - moraine, tearing off huge pieces of underlying rocks along the way and dragging them over long distances. Thus, granite boulders can sometimes be found at a distance of many hundreds of kilometers from the places of natural occurrence of granites. Deposits of water flows and reservoirs that existed inside and on the surface of the glacier remained in the form of elongated ridges - Ozov and round hills Kamov. The glacial relief is characterized by a disorderly accumulation of hills composed of sand, rubble, boulders, which alternate with depressions, often occupied by lakes and swamps. Such a relief is especially characteristic of the Karelian Isthmus, the picturesque features of which are associated with the last glaciation.

Within the territory of Leningrad region there are elevations.

Veps upland is located in the east of the region (the highest absolute height is 291 m in the region of the Gapselga ridge) and is part of the Valdai Upland.

Lembolovskie the heights are located in the central part of the Karelian Isthmus and represent a typical example of glacial relief - numerous moraine hills separated by a dense river network and shallow lakes; the highest absolute height is 205 m. A hilly-kame relief is widespread around this hill, most pronounced in the Kavgolovo and Toksovo regions.

Izhora Upland located south of the Gulf of Finland; its surface is flat, so sometimes you can find the name Izhora plateau. The Izhora Upland is composed of calcareous rocks - limestones, marls and dolomites; the highest point is 168 m. In the north, the elevation is limited by a steep ledge, which is called

Baltic-Ladoga Glint(Glint is translated from Swedish and means "ledge"), up to 60 m high. This is the coast of the ancient sea, which, forming picturesque canyon-shaped valleys, is cut through by the rivers Tosna, Sablinka, Mga, etc. Its length from west to east from the city Tallinn is approximately 400 km.

A significant part of the region's area is occupied by lowlands and lowland plains. On the southern coast of the Gulf of Finland is located seaside lowland. From the south, it is bounded by a glint and consists of several terraces corresponding to different levels of near-glacial reservoirs in different periods. Wind-blown sandstones meet here. dunes; their relative height is 10-30 m, and the width in some places is more than 10 km.

Along the southern shore of Lake Ladoga stretches Ladoga lowland, which is part of a vast lake basin, with lake terraces and sand dunes, alternating with marshy depressions and deep valleys of rivers flowing to the lake.

Most of the territory located south of the Izhora Upland and west of the Veps Upland is occupied by the outskirts Priilmenskaya lowland; flat, heavily swampy areas predominate here, as well as moraine and sandy hills and hollows with lakes. In the valley of the Neva river is Prineva lowland.

There are mineral deposits on the territory of the region. In the area of ​​the city of Kingisepp, they mine phosphate rock used for the production of fertilizers. In the east of the region, not far from the city of Boksitogorsk, there is a deposit bauxite- raw materials for the production of aluminum. In the west, near the city of Slantsy, mining is carried out oil shale, which are used as fuels, lubricating oils and chemical raw materials (for the production of plastics, medicines, etc.). On the Karelian Isthmus near Vyborg and near Priozersk, beautiful and durable crystalline rocks are mined - granites, gneisses, gabbro, quartzites, used for decorative finishing of buildings, facing embankments, making pedestals for monuments and the monuments themselves. Thanks to them, St. Petersburg acquired its "strict, slender appearance." Recall that both the Alexander Column and the columns of St. Isaac's Cathedral are made of granite. Clays, sands and limestones are mined in the pre-glint lowlands, on the Izhora Upland, on the hilly plains in the south and east. Blue Cambrian clays are used for the production of bricks, ceramic products, as well as in the production of porcelain (now also widely used in medicine and perfumery). Limestones, formed from the remains of the marine fauna of the ancient seas of the Ordovician period, are used in construction. Near the village of Pudost on the Izhora Upland there is a unique deposit " Pudozh stone " - limestone dissolved by underground waters and then carried out and redeposited by springs. When mined, it is so soft that it can be cut with a knife, but after a while it hardens and becomes very strong. Now it is used only for restoration work. Statues near the Rostral columns, the columns of the Kazan Cathedral were made of this stone, and it was also widely used in the restoration of the palace of Paul I in Gatchina. Dolomites(a type of limestone) are used as a raw material for the production of cement. In the south of the region, in the Oredezh River basin, sands- construction, molding, glass (deposits of quartz glass sands are mainly located in the Luga River basin). In addition, the following are mined in the Leningrad Region: peat- more than 2 thousand deposits, mainly in the east of the region - used as fuel, bedding for livestock, fertilizer, sapropels(silts, which are unique additives to soils to increase fertility, which are mined in 125 lakes) , mineral paints, mineral waters.

Of particular note is another very valuable mineral. Our region has huge reserves fresh water very good environmental quality. This circumstance is extremely important in the light of the ever worsening environmental situation on the globe and the associated shortage of fresh water in many regions of the world.

Climate

The climate of the region is characterized as transitional from continental to maritime, while continentality increases from the west of the region to the east and northeast: the average annual air temperature in St. Petersburg is +4.1◦С, in the western part of the Leningrad region +4.5◦С , in the north of the Karelian Isthmus +3◦, and in the north-east of the region +2.2◦С.

From the west, from the side of the Atlantic Ocean, humid sea air of temperate latitudes enters the territory of the region. In winter it is warm, causing thaws and sleet. In summer, the arrival of this air causes rain and cool weather.

The entire territory of our region is located in the zone of excessive moisture. The average annual amount of precipitation, which is 550-650 mm, is 200-250 mm more than the amount of evaporating moisture. This contributes to the waterlogging of the soil. Relative humidity is always high (from 60% in summer to 85% in winter).

A very important feature of the circulation of air masses in our region is the emergence, movement and evolution of large-scale eddies - cyclones and anticyclones, as well as the formation of atmospheric fronts due to the contact of air masses with different meteorological characteristics.

from the west, from Baltic Sea, air masses bring us rains, fogs, as well as surge waves that sometimes raise the water level in the Neva to catastrophic levels. Cyclones crossing the Baltic Sea from the southwest to the northeast form a special kind of long wave. Its height is small - 30-40 cm, and the length is comparable to the length of the sea. Swelling of water occurs in the throat of a narrow bay. The advance of the wave is almost always accompanied by a westerly wind, bringing a series of cyclones. Then the flood is inevitable. If we take into account the full flow of the Neva, then one can imagine how many troubles the movement of a huge mass of water at a speed of 100 km per hour can bring. It is estimated that during the catastrophic flood of 1924, 27 cubic kilometers of water moved eastward in 6 hours of water level rise. This amount of Don takes out in the Sea of ​​Azov for a year and a half. Sometimes floods can occur with light winds and even during calm. This means that somewhere in the vastness of the Baltic a long wave passed.

Since the birth of our city, there has been a struggle with the water element - coastal areas were washed, embankments were raised, the banks of the Neva were strengthened. The Bypass Canal was built specifically for the purpose of diverting water during floods, although the canal did not fulfill its role, because during its construction the nature of the floods in the Neva was not yet very well studied. Currently, a dam is being built to block the Neva Bay between the village of Gorskaya on the Karelian Isthmus and Lomonosov. A ring freeway will pass along the dam, which should have a positive impact on the city's ecology.

High cloudiness (total 75 sunny days per year!), high humidity, moderately warm winters and cool summers are all signs of a maritime climate.

Winter according to the classical scheme is usually snowy, in the first half it is moderately cold, with thaws, and in the second half the weather becomes more frosty. The average monthly temperature in St. Petersburg drops from -4◦С in December to -7◦С in January-February (from -8◦С to -11◦С in the east of the region). Anomalies in the weather should be noted (associated, it is believed, with the general warming of the climate on the globe) recent years- deviations in one direction or another of the average temperatures of summer or winter; but unusual winters and summers have been noted in past years. Unusually cold, for example, was the blockade winter of 1941-1942. – the average temperature for January was -18.7◦С (12◦ lower than usual); in 1924 the average January temperature was only -1.3°C, and the Neva did not freeze.

Spring begins in mid to late March; it develops slowly, the weather is quite stable and the number of days with precipitation is small. Often, Arctic air masses invade the region, and cold snaps are associated with them, sometimes in the form of frosts.

The arrival of summer in our region is marked by the onset of "white nights"; this phenomenon is associated with the latitudinal position of our region. Summers are moderately warm, although in recent decades, abnormally hot weather has been observed in some years.

At the beginning of autumn there is a short favorable period of calm and even warm weather, which is called "Indian summer". From October, the temperature drops rapidly, cyclones intensify, cloudy, cool, windy weather with drizzling rain and fog prevails, which persists into November.