Modern glaciation of continents. South America, Africa and Australia. Did you like the material? subscribe to our email newsletter

The most favorable conditions for the existence of glaciers should be sought in the polar regions of the Earth - in the Arctic and Antarctic. And the most favorable of the favorable ones are in the polar regions, which are influenced by oceanic cyclones and receive a lot of snow. The consumption of ice for melting in them is insignificant, and its arrival associated with snowfalls is relatively large. As a result, the glacier feeding limit drops very low, sometimes reaching sea level. Therefore, modern glaciation is confined to polar regions with a fairly humid, cyclonic climate. It is in them that the bulk of glaciers are concentrated, and these glaciers themselves are of the largest size and cover nature.

On the map of Northern polar region, or the Arctic, Greenland with its giant ice sheet, lying at the “junction” of the North Atlantic and the Arctic Ocean, immediately catches the eye. Smaller centers of modern glaciation with their characteristic “island” ice sheets also cling to it. In the west are the islands of Devon, Ellesmere, Baffin Island, Axel Heiberg, in the east are Svalbard (Spitsbergen), Franz Josef Land, New Earth, Severnaya Zemlya, De Long Islands.

The South Polar Region is absolutely dominated by the largest glacier on the planet - the Antarctic Ice Sheet. The glacial complexes of the subantarctic islands - South Shetland, South Orkney, South Georgia, Kerguelen, etc. - gravitate towards it.

As for the moderates and low latitudes, then glaciers can exist in them only in the mountains, especially in mountains that receive a lot of precipitation. Select any large area of ​​mountain glaciation on the world map - and it will probably turn out to be one of the record holders for the amount of snowfall. So are Alaska and British Columbia V North America, Norway, the Alps and Caucasus in Europe, the Himalayas, Karakoram, Pamir-Alai, Tien Shan and Kamchatka in Asia, the Andes in Patagonia and the Southern Alps in New Zealand.

Each of the named areas of modern glaciation is famous in its own way. Thus, the reticulated glaciers of Southeast Alaska and the Patagonian Andes are combined with the picturesque landscapes of the “alpine” highlands and fjord coasts; their “tidal” glaciers, such as the famous Columbia (with an area of ​​1370 square km), are among the largest. The foothill glaciers of Alaska are unique: it is enough to name the largest in temperate latitudes, the Bering glacier (area 5800 square km) and the foothill glacier Malaspina on the southern coast of Alaska (area 2200 square km), included in all textbooks.

The valley glaciers of the Alps - the Great Aletsch, Fernagtferner, Hintereisferner - are much smaller than the Alaskan ones, but they were the first objects of glaciological research. Their study can be considered the first steps in understanding the laws of movement and oscillations of glaciers. But the Himalayas, Karakoram, Pamir and Tien Shan are famous for their huge dendritic glaciers. The most famous of them are Siachen, Biafo, Baltoro, Fedchenko, South Inylchek - each 60-77 km long with colossal pools covering an area of ​​many hundreds of square kilometers.

In Africa, as in the entire equatorial belt of the globe, modern glaciers can exist only on the tops of the most high mountains ny structures. Here, only three mountain ranges rising above 5000 m bear modern glaciers and bear traces of more extensive glaciation in the past.

These are the Pleistocene-Holocene volcanic structures of Kilimanjaro (5895 m) and Kenya (5199 m) on the eastern flank of the East African Rift Zone and the Rwenzori mountain range with Margaret Peak (5109 m) - a horst rise at the intersection of the Edward George and Albert grabens, composed of Precambrian gneisses.

All three named mountain ranges are located near the equator, not far from each other. Therefore, the climatic conditions for the existence of glaciers on them are similar.

A common feature of the climate is the division of the year into two wet and two dry periods, with slight fluctuations in temperature conditions throughout the year.
Dry periods occur in January - February and July - October, and wet periods occur in March - June and November - December.
Wet periods with predominant cloudy weather are periods of predominant accumulation of snow in the glacial zone, and dry periods with little cloudiness are periods of predominant ice ablation. This is reflected in the stratigraphy of the firn strata.

Thus, in the firn region of the Lewis Glacier (Kenya), the layered structure of firn was traced over a number of years in boreholes and in a 20-meter crack. Each pack of layers consisted of layers of dense firn with ice layers and layers separating them dirty ice. Each layer of dirty ice corresponds to an ablation period, and each layer of clean ice corresponds to an accumulation period. A similar alternation of clean and contaminated ice was also noted in the section of the firn strata on the Elena glacier (Rwenzori).

The bulk of precipitation feeding the glaciers is brought by the southeast trade wind from the water area Indian Ocean. South-westerly winds bringing moisture from Atlantic Ocean, are of less importance. The main factor in glacier ablation is solar radiation. Its share accounts for about 90%, and turbulent heat exchange only 10% of the total energy consumption for melting and evaporation of ice. In this regard, changes in cloudiness and shading by slopes play a greater role in glacier ablation than fluctuations in temperature conditions.

The modern snow line rises highest on Kilimanjaro - up to 4800 - 5200 m, on Kenya it is at an altitude of 4680-4750 m, and on Rwenzori - at 4570 - 4750 m. The difference in the height of the snow line is apparently associated with less cloudiness and less rainfall in the glacial zone on Kilimanjaro compared to Kenya and Rwenzori.

According to observations on Rwenzori, the maximum precipitation falls below the snow line, at an altitude of 3300 m, where it reaches 2300 mm per year. At the level of the snow line, about 2000 mm falls, and at an altitude of 5000 m, the annual precipitation drops to 1150 mm. Kilimanjaro receives less precipitation than Rwenzori, and its amount decreases more rapidly with altitude. According to observations over 5 years (1945-1949), the average annual precipitation decreased from 1800 mm at an altitude of 2850 m to 180 mm at an altitude of 4300 m and to 70 mm at 5800 m.

Thus, firn areas of glaciers receive very poor nutrition, which does not compensate for the loss of snow and ice due to melting and evaporation. The material balance of glaciers is currently negative and has been negative all the time since the end of the last century. It is reasonable to assume that if climatic conditions do not change, the glaciers of Kilimanjaro, Kenya and Rwenzori will cease to exist over the next century.

Kilimanjaro Glaciers

Kilimanjaro (3°05′ S, 37° 22′ E) is the largest volcanic massif in Africa with a diameter of about 100 km, formed by three merged volcanoes: Mawenzi (5183 m), Shira (4005 m) and Kibo (5895 m). Volcano Kibo is the youngest and highest, and only it has modern glaciers. At the top of Mawenzi, migratory snow patches periodically form.

In the late Pleistocene, a vast caldera more than 3 km in diameter formed at the top of Kibo, and above its flat bottom - a younger cone with an internal crater and a very recent outlet (the volcano was active in the Holocene, but is now in the solfatorium stage). The height of the ridge-shaped shaft surrounding the young crater ranges from 5800 to 5895 m. The outer slopes of the volcano are dissected by radial valleys, along some of them glaciers descend, most of which begin from the shaft surrounding the caldera at the top of the volcano. In the caldera itself, only scattered blocks of dead ice have survived from the once continuous ice cap.

There are a total of 11 glaciers on Kibo, the total area of ​​which, measured on a 1964 map (scale 1:25,000), is about 7 km². The largest glacier, Penka, 2.4 km long, descends along the western slope of the volcano without a clearly defined valley from 5800 to 4580 m. The upper edge of the Penka glacier, like other glaciers of the northwestern group, ends towards the crater with a vertical wall 30-40 m high Over half a century (from 1912 to 1959), the end of the glacier retreated from the terminal moraine with an ice core by about 500 m.

Along the northern side of the caldera, from the Penka glacier to the east and southeast, the Severny slope-type glacier stretches. Both the lower and upper edges of this glacier are sheer ice walls 30-40 m high. On the southern slope of Kibo, 4 glaciers descend steeply from the general area of ​​accumulation, which in the upper reaches is also terminated by a vertical wall of ice that has retreated from the caldera ridge. From this group of glaciers last years The Ratzel glacier became detached. Previously, these glaciers reached a steep cliff on the slope of the volcano and fell from it in avalanches, forming a revived glacier at the foot of the cliff, ending behind the shaft of the terminal moraine. Now they do not reach the cliff, and the power of the revived glacier has stopped. Inside the caldera, scattered blocks of ice 30-60 m thick stand apart from each other, their slopes are cut by deep hollows with pyramidal peaks between them.

The collapse of the single ice cap on the top of Kibo apparently began at the end of the last century. In 1889, the ice in the caldera was already divided into several large massifs. By 1957, some of them had completely disappeared, and the rest had significantly decreased in size. The process of collapse and retreat of the glaciers of Mount Kilimanjaro continues.

Glaciers of Kenya

Kenya (0°10′ S, 37°10′ E) is an extinct, heavily eroded volcano with alpine landforms, the second highest in Africa. The vast volcanic massif is crowned by sharp peaks, among which two main ones stand out: Batian, or Kenya (5199 m), and Nelion (5188 m).

In total, in 1978 there were 12 glaciers with a total area of ​​0.7 km². The largest of them, Lewis Glacier, descends along the south-southwestern slope of the volcano from Lenana Peak (4985 m) to an altitude of 4580 m and ends in a small periglacial lake. From 1926, when the size of the glacier was first measured, it continuously retreated until 1974. average speed about 10 m per year.

During this time, it became shorter by 395 m, and its end rose 130 m higher up the slope. The vacated bottom of the valley was occupied by a periglacial lake, which did not exist before 1934. After 1974, the retreat of the glacier stopped, and until 1978 it was stationary. In 1978, it was about 1 km long and 0.3 km² in area. The firn line passed at an altitude of 4750 m.

The second largest glacier - Tyndall - descends to the south from the peak of 4780 m and ends at an altitude of 4500 m. In 1926, the end of the glacier descended into the periglacial lake of the same name, but by 1958 it retreated from it by 130 m horizontally and by 50 m vertically. Subsequently, the retreat of the glacier stopped, and until 1978 the position of its end did not change. The height of the firn line is 4700 m.

The Caesar Glacier retreated by 250 m from 1929 to 1958. The Darwin Glacier, also located on the southern slope, has a very short tongue, but it also retreated by about 80 m. During the period under review, almost all glaciers in Kenya shrank, and only at the end of 70 's, this process slowed down and stopped on some glaciers. Detailed measurements showed that between 1963 and 1978. the total area of ​​glaciers in Kenya decreased by 18%, and from 1926 to 1978 - almost halved - from 1.2 to 0.7 km². Kenya's glaciers, like Kilimanjaro, are little active. The maximum measured speed of ice movement in the middle part of the Lewis Glacier was 4.6 m/year.

Rwenzori Glaciers

Rwenzori (Mountains of the Moon) is a highly dissected mountain range, a horst of Precambrian gneisses among the rocks of the volcanogenic complex, stretching from south-southwest to north-northeast for almost 120 km.

Glaciers are concentrated in the central group of the highest mountains located between 0°20′ and 0°26′ N. w. and 29°51′ and 29°56′ E. In total, there are 37 glaciers on Rwenzori with a total area of ​​about 5 km². The bulk of glaciers are located on the Stanley (Margarita Peak, 5109 m), Speke (4890 m) and Baker (4843 m) mountain ranges.

The central part of the Stanley Massif, surrounded by high peaks, is occupied by a firn field, from which 7 glacial tongues descend in different directions - Margarita, East Stanley, Helena, West Helena, Moebius, West Stanley, Alexandra, and 7 more glaciers exist independently of the main firn field. The glaciated area of ​​the Stanley Massif is about 2 km². The height of the firn line on the Elena glacier is 4560 m.

Above 4650 m, a decrease in accumulation and an increase in ablation was noted due to a decrease in cloudiness and an increase in radiative melting and evaporation. Thus, the net accumulation in 1958 decreased from 1220 mm at an altitude of 4635 m to 860 mm at an altitude of 4920 m. In the stratigraphic section of the firn, an alternation of clean and contaminated layers was observed. The thickest contaminated layers are formed in January - February. Most glaciers are retreating. The West Stanley Glacier has been retreating continuously since 1932, and in just one decade, between 1940 and 1950, it became shorter by 245 m.

The top of the Speke massif is covered with a firn field 2.5 km long and up to 1.2 km wide, from which short blades of glacial tongues extend. According to observations in 1958-1961, the area of ​​the accumulation region was twice the area of ​​the ablation region, and the total glaciation area of ​​the Speke massif was 1.6 km². The firn line ran at an altitude of 4570 m. Between 1950 and 1956. the ends of the glaciers retreated by 60-70 m.

The Vittorio Glacier is the largest on Rwenzori. Its width exceeds its length, and three short tongue, which over the past half century have been slowly retreating, like all the other glaciers of the Speke massif.

There are 6 small glaciers on the Baker Massif with a total area of ​​0.67 km². They do not have a common firn pool, but exist independently. These glaciers were first visited in 1906. At that time, the East and Middle Baker glaciers and the Moore Glacier shared a common firn basin, but by 1963 they separated, and now the Moore Glacier lies entirely below the firn line. While maintaining unchanged climatic conditions it was supposed to disappear in 20-30 years. We don’t know what the state of the glacier is now, but several smaller glaciers that were observed at the beginning of the 20th century have disappeared.

Six small cirque glaciers with a total area of ​​0.26 km² are located on the Jesse massif. They all retreat. In the south of the massif from the city of Yolanda, several steep glacial tongues descended from the common firn basin in 1931. By 1959, this glacial massif had broken up into several parts, which continued to degrade in 1966.

In the southern part of Rwenzori, the summit of Luigi di Savoia (4626 m) was covered with a thin layer of ice in 1906. In 1932, at the source of the river. Kurugata, 5 small glaciers with signs of retreat were discovered. None of them ate firn fields. In 1960, the glaciated area of ​​this mountain decreased to 4 hectares.

Three isolated glaciers with a total area of ​​0.08 km² have been preserved in the northern part of the Rwenzori massif, on the city of Emin.

In the late Paleozoic, along with areas of warm tropical climate, there were also polar zones. The widespread development of continental glaciers in the late Paleozoic (middle, late Carboniferous) has been reliably established in southern Africa, Australia, India, South America, and Antarctica. Moreover, by the characteristic strokes, grooves, scratches that glaciers leave on rocks during their movement, by the peculiarities of the location of moraine deposits, it is possible to restore the direction of movement of Late Paleozoic glaciers. It is believed that there were several glaciation centers where glaciers originated and from where they began their movement.

In some cases, it seems as if the centers of glaciation were located outside the modern continents. So in South Africa, near the city of Durban, the ice moved from the direction of the modern Indian Ocean. This speaks in favor of the existence of a single supercontinent Gondwana in the late Paleozoic. In this case, the center of glaciation could be located in Antarctica, immediately adjacent to southern Africa. True, there are other opinions. French geologist Fourmarier believes, for example, that the hypothetical center of glaciation, from where glaciers advanced onto the area of ​​the city of Durban, is currently separated from Africa by a deep fault and hidden under the waters of the Indian Ocean.

The glaciation of the late Paleozoic was enormous. Judging by the thickness of the accumulated moraines (up to 300-600 meters), it can be assumed that the central regions of Gondwana in the Carboniferous were covered with an ice shell, the thickness of which could reach 5-6 km. Periodically, glaciers partially melted. In such periods, interlayers of ribbon clays appear in the strata of chaotic moraine deposits. Many scientists see the reasons for the Late Paleozoic glaciation in a different location of the poles (the south pole, for example, was located in southern Africa), in a different circulation of air masses and in the relatively high hypsometric position of Gondwana above sea level (it is known that the higher we rise, the colder it becomes; On average, per 1000 meters of ascent, the temperature drops by 3-5°C).

Basically, the tropics then passed along the northern and northeastern shores of the sublatitudinal Tethys Ocean, covering modern areas of Europe, partially Central Asia, western North America, northern Africa, northern and western South America. The dots in the figure show areas of glaciation. They were located in the center of Gondwana. The area of ​​Late Paleozoic glaciation was unusually large. This raised doubts about the possibility of the existence of such grandiose glaciers. Some scientists even believe that there would not be enough water on Earth to form such huge glacial masses. They do not reject the existence of glaciers, but it is assumed that their sizes were much more modest. One thing is certain: in the late Paleozoic there was a clearly defined climatic zonation. The polar climate zones gave way to a temperate climate zone, which in turn turned into a tropical zone.

In Kamchatka, in a small area of ​​the valley of the river of the same name, there is a giant mammoth cemetery. Tusks, skulls, individual parts and entire skeletons are exposed in an almost continuous strip in the river cliff and, washed away by water, are carried downstream. Hundreds of giant northern elephants met their death here. Beyond this central section In the Kamchatka valley, mammoth bones are rare. The massive death of herbivorous giants here was caused by the rapid cooling. The Kamchatka Valley is surrounded on all sides by chains of volcanoes and mountain ranges. The cooling first led to the formation of glaciers in the mountains. Gradually, the area of ​​glaciation expanded, and the glaciers themselves, descending lower and lower into the intermountain valley, eventually closed it on all sides with an ice barrier. There was a small piece of land left in the river valley that was not captured by ice. Mammoths from all over the Kamchatka Valley moved here. Even though glaciers never covered this small piece of land, the animals could no longer survive. The trouble was not only that the pasture area was insufficient for such a huge herd. The cause of the disaster was nearby glaciers, which sharply lowered the temperature of the area.

The mammoth cemetery in Kamchatka is not the only example of the catastrophic impact of climate change on vegetation and animal world during the great glaciations.

Now large glaciers exist only on high ridges and in the polar regions. Thus, on the Antarctic continent the thickness of the ice sheet reaches 4500 m, in Greenland - 3300 m. The thickness of the tongues of large glaciers in the Caucasus is 100 m, in the Tien Shan and Pamir - 560-600 m, and in the Fedchenko glacier - about 1000 m.

The ice cover 10,000-20,000 years ago occupied huge spaces of our planet. Much of Europe and North America was covered in ice. Descending from the Scandinavian mountains, the glacier reached Volgograd and Kyiv, covering the territory of Poland and England (Fig. 6).

Glaciation in the Quaternary period was not a single major cooling, but consisted of a series of glacial and interglacial eras, each of which in turn was divided into several stages. The figure shows how the ice sheet of the Valdai glaciation retreated (degraded) on the Russian Plain. We see that the gradual decrease in the area of ​​the glacial shell was accompanied at times by its growth. It is obvious that this, in turn, was a consequence of temperature fluctuations with a periodicity of about 1000 years.

However, even shorter-term fluctuations in the average annual temperature on the Earth's surface are also known. Thus, since the beginning of this century, the Arctic has become noticeably warmer. This was expressed, in particular, in a decrease in ocean ice cover, an increase in navigation time, etc. But since 1940, cooling began again, continuing to the present day.

Can we classify the glaciation periods of our planet as catastrophic phenomena? Absolutely yes. On the scale of geological time, they occurred almost instantly.

The ice moving from the north caused a gigantic movement of peoples from north to south, as well as a radical change in their way of life. Climate change was one of the most important factors, on the one hand, rapid development, on the other hand, the extinction of individual tribes. Suffice it to say that the area of ​​the globe suitable for human habitation was 30 million km 2 less than at present.

What caused such a sharp cold snap on our planet, and can we expect a new outbreak of cold in the future?

It has been established that the sharp cooling that intensified in the north of our planet about a million years ago, i.e. at the beginning of the Quaternary period, was not the only one in the history of the Earth. In Africa, South America, India and Australia, glacial deposits have been discovered in sediments formed 300 million years ago (during the Carboniferous period). Even more ancient traces of glacial activity are also known - the Riphean glaciation 600-700 million years ago. The most ancient glacial formations are over a billion years old.

It has been noted that all the great glaciations of our planet coincided with the largest mountain-building epochs, when the relief earth's surface was the most contrasting. The area of ​​the seas has decreased. Under these conditions, climate fluctuations became more severe.

Analyzing the plant communities that existed on our planet in the last 30-50 million years, scientists noticed that the climate on our planet was gradually deteriorating - a slow cooling was occurring. It is associated with increasing mountain building, and primarily with an increase in the absolute height of the relief on the Antarctic continent. Mountains up to 2000 m high that arose in Antarctica, i.e. directly to South Pole The lands became the first source of formation of ice sheets. It has now been established that glaciation of Antarctica began more than 30 million years ago. The emergence of a glacier in Antarctica greatly increased the reflectivity on this continent, which in turn led to a decrease in temperature. Gradually, the glacier of Antarctica grew both in area and in thickness, and its influence on the thermal regime of the Earth increased. The temperature of the ice slowly dropped. The Antarctic continent has become the largest cold accumulator on our planet. Thanks to sea ​​currents and atmospheric circulation, the cold from the Antarctic continent spread throughout the planet and the cooling on Earth gradually intensified.

Mountain-forming processes, which led, in particular, to the growth of mountains in Antarctica, are a necessary, but not yet sufficient condition for the occurrence of glaciation. The average heights of mountains are currently no lower, and perhaps even higher, than they were during the glaciation that occurred at the beginning of the Quaternary period, but now the area of ​​glaciers is relatively small. Obviously, some additional reason is necessary that directly causes the sharp cold snap.

There are many hypotheses about this. Before dwelling on some of them, it should be emphasized that any significant decrease in temperature is not required for the occurrence of major glaciation of the planet. Calculations show that the overall average annual decrease in temperature on Earth by 2-4 ° C will cause the spontaneous development of glaciers, which in turn will lower the temperature on Earth. As a result, the glacial shell will cover a significant part of the Earth's area.

What determines the decrease in the average temperature of the Earth?

It has been suggested that the cause is a change in the amount of heat received from the Sun. Above we talked about the 11-year periodicity of solar radiation. There may be longer periods. In this case, cold snaps may be associated with minimum solar radiation. An increase or decrease in temperature on Earth occurs even with a constant amount of energy coming from the Sun, and is also determined by the composition of the atmosphere.

In 1909, S. Arrhenius first emphasized the enormous role carbon dioxide as a temperature regulator of surface layers of air. Carbon dioxide passes freely Sun rays to the earth's surface, but absorbs most of the earth's thermal radiation. It is a colossal screen that prevents the cooling of our planet. Currently, the carbon dioxide content in the atmosphere does not exceed 0.03%. If this figure is halved, then average annual temperatures in temperate zones will decrease by 4-5 ° C, which could lead to the onset of an ice age.

The study of modern and ancient volcanic activity allowed volcanologist I.V. Melekestsev associated the cooling and the glaciation that causes it with an increase in the intensity of volcanism. It is well known that volcanism significantly affects the earth's atmosphere, changing its gas composition, temperature, and also polluting it with finely divided volcanic ash material. Huge masses of ash, measured in billions of tons, are ejected by volcanoes into the upper atmosphere and then carried by jet streams throughout the globe. A few days after the Bezymyanny volcano erupted in 1956, its ashes were discovered in the upper troposphere over London. Ash material released during the 1963 eruption of Mount Agung on the island of Bali (Indonesia) was found at an altitude of about 20 km above North America and Australia. Pollution of the atmosphere by volcanic ash causes a significant decrease in its transparency and, consequently, a weakening of solar radiation by 10-20% against the norm. In addition, ash particles serve as condensation nuclei, contributing to large cloud development. Increasing cloudiness, in turn, significantly reduces the amount of solar radiation. According to Brooks' calculations, an increase in cloudiness from 50 (typical for the present) to 60% would lead to a decrease in average annual temperature by globe at 2° C.

Ancient metamorphosed moraines are called tillites. The relationship of tillites with other rocks, the presence in their composition of boulders with glacial shading or pebbles bearing traces of characteristic glacial processing, unsorting and other features make it possible to distinguish them from sedimentary rocks and identify them even in the most ancient strata. Currently, tillites are found in Archean deposits of North America and Africa (Congo River basin), in Proterozoic China (Nantou Formation), Africa, Australia, the European part of Russia and Siberia (Yenisei Ridge). Proterozoic moraines are perfectly preserved. They are overflowing with streaked boulders and pebbles and, despite intense metamorphism, have an extremely characteristic appearance. In the Paleozoic, glaciations were very widespread in the territory of the modern tropics. Upper Paleozoic tillites are known in South America, Africa, India and Australia. From these glaciations, in addition to well-preserved moraines, other traces of glacial activity remained - ribbon clays, sheep's foreheads polished by ancient glaciers, etc.

There are no known major glacial epochs in the Mesozoic. Glaciations reached a large scale only in the Quaternary period, when a general cooling of the climate occurred. At this time, one of the centers of glaciation was on the Scandinavian Peninsula, from where glaciers spread throughout Europe. Another major center was in the Alps. Alpine glaciers extended far into the surrounding plains. In Asia, the Himalayas and others mountain systems were covered by glaciations comparable to those of the Alps. In Africa, glaciers descended from the volcanoes of Kenya and Kilimanjaro much lower than at present. In South America, huge glaciers descended from the Andes into the tropical plains. The moraines deposited by them stretch along the ridge. In North America, glaciers descended from three centers - Labrador, Keewatin and Cordillera - well south of the Great Lakes, but the northern tip of the continent was not subject to glaciation.

The glacier from the Scandinavian center crossed the waters of the modern North Sea and connected with the local glaciers of Great Britain, covered the entire North German Lowland, where its movement was stopped by the heights of the Harz and Giant Mountains, on the northern slopes of which Norwegian boulders rise to a height of 580 m. On the Russian Plain, the glacier descended to 50° N. w. two powerful languages ​​along the valleys of the Dnieper and Don. Like modern sheet glaciers, the Scandinavian glacier moved in a thick layer, crushing and twisting the underlying rocks, pushing them on top of each other. Judging by the height of the distribution of exotic boulders left by the glacier in the Giant Mountains, the thickness of its ice on the Scandinavian Peninsula was at least 2 thousand m. On the southern coast of the Baltic Sea it reached 1000 m. In the Moscow region, the thickness of the ice is believed to have exceeded 1000 m. The glacier advanced three times, leaving a cover of bottom moraine - boulder loams and sandy loams with boulders from Scandinavian, Finnish and local rocks.

The time of the most ancient Quaternary glaciation was established in the Alps and named after the river. Mindel by Mindel century. Subsequently, the time of the first Quaternary glaciation in the Russian Plain was also called Mindelian. This glaciation covered the entire Northern Europe, Caucasus and other mountainous regions. In Europe, the Mindel glaciation extended to the Carpathians. In Russia, the glacier reached the city of Mozyr on the river. Pripyat, middle reaches of the river. Oka and further to Solikamsk. Not all geologists, however, share the opinion about the presence of the Mindel glaciation in Russia, pointing to the absence of traces of cooling, which affected changes in fauna and flora. In the south of Russia, remains of southern animals (elephants, rhinoceroses, horses, bison, etc.) and heat-loving plants are characteristic of this time.

After the retreat of the Mindel (Likhvinsky) glacier, the climate warmed significantly and many heat-loving plants (hornbeam, boxwood, rhododendron along with pine, spruce, etc.) and animals (hippos, elephants, elasmotherium, camels, rhinoceroses, bison, horses and others) penetrated far on North. This era was called the Mindelris interglacial, since in the Alps it separated the Mindelian glaciation from the next Risian.

The Ris glaciation was the largest. Ice covered all of Northern Europe and extended south of London and Berlin. In Spain, France and Italy, glaciers from the mountains descended deep into the lowlands. In Ukraine, the glacier descended along the Don and Dnieper valleys south of Kyiv, Kharkov and Voronezh. Asia also underwent significant glaciation: glaciers covered the Northern Urals, Northern Tien Shan, Pamir, Altai, Sayan, Verkhoyansk and other ranges of Siberia. In the central part of Yakutia, powerful immobile masses of firn accumulated. Glaciers penetrated to the north of the West Siberian Lowland, advancing from the Urals, Novaya Zemlya and Yenisei. The Rissky, or Dnieper, glacier retreated very quickly, leaving behind no final moraine (only the bottom one). But the cooling that accompanied this glaciation affected the flora and fauna. In Europe, many cold-loving animals penetrated far to the south - musk ox, mammoth, woolly rhinoceros, reindeer, etc.

The Riss glaciation gave way to a very short interglacial (Risswürm, or Mikulin). The interglacial fauna contains some heat-loving forms (saiga, wild horse, jerboa, etc.).

The last advance of the glacier (Vistula glaciation) spread only to the North German Lowland and the north of the European part of Russia. Two maxima of this glaciation are noted: during the first, the ice peak reached Smolensk and Kostroma (Kalinin glaciation), during the second - to Vilnius and Ostashkov (Valdai, or Ostashkovo, glaciation). Both maxima are usually compared with the Würm glaciation in the Alps. During the retreat, the glaciers of this glaciation left concentric ridges of terminal moraines, numerous eskers, kamas, drumlins, glacial lakes and other characteristic forms of moraine landscape, widespread in the northern and northwestern regions of the European part of Russia.