The Quaternary period of the Cenozoic era was marked by large-scale glaciation, which had a huge impact on the development of life on the planet. As the glaciers advanced, the climatic barrier of life was slowly pushed back to the south, and the rugged vegetation of the Cenozoic was also retreating to the south. In the interglacial epochs, it again returned to its original territories. True, in some regions of the world, the return of vegetation back was often blocked by mountain ranges, which predetermined the extinction of many plants of the temperate zone. Some groups of animals, directly or indirectly dependent on certain types of vegetation, also shared their lot.
Many representatives of the animal world managed to adapt to the intensifying cold weather, having acquired thick wool. The Pleistocene era is characterized by the widespread distribution of saber-toothed cats, marsupials and cave lions. In the Pleistocene, the first people appeared, and many large mammals, on the contrary, began to die out. Cold snaps alternated with warming. During the Ice Age, three zones of vegetation were clearly distinguished on the planet: tundra, steppe and taiga. They were located south of the advancing glaciers, in an area 200-320 km wide. Thus, repeated glaciations significantly devastated the flora of the planet, and the return of thermophilic plants from the south to the north was hampered by mountain ranges that acted as barriers to vegetation dispersal.
Nevertheless, in the warmest interglacial epochs of the Quaternary period, deciduous forests were widespread, in which oak, beech, linden, maple, ash, hornbeam, alder, walnut and hawthorn predominated. During large-scale glaciation, water vapor condensed in the form of snow, but the melting of ice and snow produced less water annually than snow fell. The gradual accumulation of ice reserves on land contributed to a decrease in the level of the World Ocean. Therefore, in the Quaternary period, special land bridges arose between continental Europe and the British Isles, Asia and North America, the Amur Region and Sakhalin, as well as between the Indochina Peninsula and the islands of the Sunda Archipelago.
These land bridges were used to exchange animals and plants. At the same time, it was the absence of a connecting link between Asia and Australia that saved the life of cloacal and marsupials, which in the Tertiary period were completely supplanted by placental mammals on other continents of the planet. In the Quaternary period, various groups of mammals met, and in particular, elephants. The largest of them lived in forests and had a height at the shoulders of over 4 m. In the Siberian tundra, the cold-loving mammoth Mammuthus primigenius, covered with thick and long reddish wool, took a dominant position. In one of the ice ages, mammoths probably crossed the ice of the Bering Strait and settled throughout North America. The skeletons of heavy mastodons are often found in this region of the world today.
Prominent representatives of the fauna of that time were large woolly rhinos, which in the era of glaciation lived in the tundra next to mammoths. There was also a resettlement of horses, whose homeland is North America. Moving through Asia and Europe, they gradually settled around the world. It is noteworthy that in North America itself, horses became extinct by the end of the Pleistocene and returned there only with the European conquerors. It is a pity that we were never able to see them, since these animals had an amazing appearance. Today, many fans of the fauna world like to put pictures of animals in photo frames and hang them on their walls. But, of course, it is better to insert photographs of loved ones there.
Numerous subspecies of the wild horse inhabited the savannas of the European continent as early as the beginning of the Quaternary period. Among the ruminant artiodactyls, one can distinguish a huge large-mouthed deer, the distance between the horns of which reached 3 m. Musk oxen, primitive bison and tur, the ancestors of modern domestic bulls, multiplied in large numbers. During the Quaternary period, our planet was also inhabited by numerous predators, among them the huge cave bears Ursus spelaeus, the Machairodus saber-toothed tigers, whose long fangs resembled the crooked Turkish scimitars, and the cave lions Pamhera spelaea. During the glacial stage, the well-known hyenas, wolves, foxes, raccoons and wolverines already lived.

The Holocene epoch of the Quaternary period is the time of the formation of the modern appearance of the fauna and flora of our planet. The variety of living organisms today is noticeably less than in past geological eras. This may have been facilitated by the intense human impact on the environment. The appearance of the first great apes in the Tertiary period ensured their further evolution in the Quaternary period of the Cenozoic. It became possible for the appearance of the ancient ancestors of modern man - Driopithecus and Australopithecus. The next stage in the evolutionary ladder is the emergence of a skilled man, the first representative of the genus Homo, and, finally, the species to which people living now belong - Homo sapiens. From that moment on, a completely new life began on the planet.
In connection with the emergence of modern humans and the development of human civilization during the Quaternary period, it was proposed to call this stage of the Cenozoic era an anthropogen. During the Holocene era, human civilization spread throughout the world. It gradually became the most important global factor that changed the biosphere of our planet. In particular, the emergence of agriculture has destroyed a large number of species of wild plants in order to clear crops and pastures. In many cases, human activities were ill-conceived and destructive to their environment.
Thus, the Quaternary period of the Cenozoic took place with the participation and significant influence of man on the world around him. As the ice melted, the settlement of human civilization took place on the territories liberated from under the glaciers. During this period, mastodons, mammoths, saber-toothed tigers and large-horned deer gradually became extinct. Again, ancient people who were actively engaged in hunting played a significant role in this process. They exterminated the mammoth and woolly rhinoceros in Eurasia, as well as mastodons, horses and sea cows in America. Plowing of land, widespread hunting, burning of forests for pastures and trampling of grass stands by domestic animals have reduced the habitats of many steppe fauna. Human activities contributed to the expansion of desert areas and the emergence of mobile sands.
The division and movement of separate continents, as well as the establishment of climatic zoning, led to the isolation of the representatives of the biosphere by region. The development of life in the Cenozoic provided the biological diversity on Earth that we can observe today. The result of the long evolution of life on our planet was the emergence of Homo sapiens at the end of the Quaternary period of the Cenozoic. With the end of prehistoric times, man began to create his own history. If about 4 thousand years ago about 50 million people lived in the world, then in the first half of the 19th century the number of people on the planet exceeded one billion. It is human activity that largely predetermined the species composition of the biosphere that exists at the present time. Man has also influenced the modern geographic distribution of living organisms on Earth.

This era is subdivided into the Paleogene, Neogene and Anthropogenic periods. There was a division of the Cenozoic era and for two periods - the Tertiary and the Quaternary, of which the Tertiary combined the Paleogene and the Neogene, and the Quaternary corresponded to the Anthropogenic period.

In the Paleogene and especially in the Neogene, a new powerful folding and mountain building takes place, which is called the Alpine era. There are several phases of folding, of which the most intense are in the Neogene. During this era, the largest mountainous countries were formed (Atlas, Andalusian mountains, Pyrenees, Apennines, Alps, Carpathians, mountains of the Balkan Peninsula, mountains of Asia Minor, Caucasus, mountains of Iran, Pamir, Himalayas, mountains of Southeast Asia and the Malay archipelago, mountains of Kamchatka and Sakhalin, continued to form Cor-

dealers and Andes of North and South America). In addition, in a number of more ancient mountainous countries, already severely destroyed by this time by denudation, new powerful faults arose, uplifts and subsidences occurred (central Europe, Tien Shan, Altai, etc.). Simultaneously with mountain building, which took place mainly in the northern hemisphere, Australia separated from Asia in the southern hemisphere, a depression of the Red Sea was formed, deep faults dissected East Africa, large faults spread to the northern hemisphere, where the formation of the northern part of the Atlantic Ocean took place, the depression of which acquired outlines close to modern ones. Areas of manifestation of volcanism were close to the existing ones at the present time.

Mountain building, which took place on the outskirts of previously formed platforms, involved these platforms in its movement, in connection with which the outlines of the seas changed greatly. On the territory of the USSR, powerful transgressions covered the south of the Russian Plain, Central Asia, and Western Siberia.

The climate in the Paleogene (before the manifestation of intense mountain building) is warm, humid without sharp fluctuations in temperature over vast areas. In the Neogene, the climate becomes more continental, with sharply defined climatic provinces, but remains generally warmer than modern.

The flora of the Paleogene and Neogene, which was dominated by angiosperms, is very similar to the vegetation of modern tropical and subtropical latitudes, and these plant species spread in the Paleogene all the way to the northern islands of Europe and North America. In the Neogene, the area of moisture-loving forests was greatly reduced; in temperate latitudes, drought-resistant flora and steppe areas appeared.

The fauna of the Paleogene and Neogene is rich and diverse. On land, the dominant position is occupied by various mammals and birds. The marine fauna is becoming very close to modern; marine mammals appear. In the Neogene, with the appearance of steppe spaces, ungulates (antelopes, horses, etc.) quickly begin to evolve. At the same time, the development of anthropoid occurs. The remains of a monkey-man (Pithecanthropus) were found in the Neogene deposits of Java Island, and in China - a man (Sinatropus) who used stone tools and fire.

The deposits of the Paleogene and Neogene are rich in various minerals, among which the deposits of oil, gas and coal are of great importance.

Climate changes, which began in the Neogene, led at the beginning of the Anthropogenic (Quaternary) period to a significant cooling, as a result of which, first in the mountains, and then on the plains, powerful glaciation develops. During the Anthropogenic period, these glaciers either grew strongly, then sharply decreased approximately to the present size. In this regard, it is customary to distinguish between glacial epochs and interglacial epochs. For Eastern European

plains, most researchers indicate four glaciations: Oka, Dnieper, Moscow and Valdai. The boundaries of the two glaciations are shown in Fig. 28.

Significant climate changes have strongly affected the composition of flora and fauna. During the Anthropogenic period, polar and temperate

latitudes are inhabited by animals and plants adapted to the harsh climatic conditions. Instead of the thermophilic flora of the Neogene, forests of the taiga type develop here, and later, tundra flora appears.

During this period, the duration of which is relatively short (1 000 000 years), there were no major changes in the outlines of the seas and continents. Small transgressions and regressions of the sea took place in the coastal strip of the World Ocean in interglacial and postglacial times. The sizes of closed basins (Caspian Sea) changed more significantly. In this regard, deposits of marine origin in the area of modern continents are very limited in distribution. More widespread are continental deposits (glacial, riverine, lacustrine, boggy, etc.).

After the intense manifestation of mountain building that occurred in the Neogene, the movements of the earth's crust in the Anthropogenic period did not stop and continue to the present time, as evidenced by strong earthquakes, volcanism, uplift and subsidence of large blocks of the earth's crust that occur in zones of alpine folding. All these processes, together with the activity of external geological agents, affect the ancient relief of the lithosphere and are reflected in its modern relief.

In general, the Cenozoic era was marked by very important events to date. 1. There was a new - alpine mountain building (see Fig. 27), mountain structures have risen, which are currently the highest mountains of the Earth. 2. Mountainous countries that arose in the Paleozoic and Mesozoic eras. by the beginning of the Cenozoic, they were badly destroyed. In the era of Alpine folding, they experienced repeated movements, were broken by faults, raised to great heights and again turned into mountainous countries with sharp relief forms. 3. There was a further reduction of geosynclines and, due to them, the platforms grew. 4. The uplift of young mountain ranges was accompanied by the uplift of adjacent platform sections, which affected the distribution of land and sea. This was also influenced by faults in the earth's crust that divided the continents. 5. As a result of volcanism, extensive lava plateaus and plains were formed, high volcanic mountains and highlands arose, new deposits of minerals were formed in the bowels of the Earth (currently still hidden under a thick sedimentary cover). 6. The climate has changed dramatically. From warm and monotonous, characteristic of the beginning of the Cenozoic era, it became sharp, with a large number of climatic zones and provinces. 7. Large glaciers have appeared, repeatedly spreading over vast areas of land. 8. The fauna and flora have taken on their modern appearance. 9. A man appeared and began his activity.

In concluding this brief description of the geological history of the Earth, it should be noted its complexity. Without touching on the development of the organic world, let us turn to the issues of the development of the lithosphere and its relief, taking the territory of the USSR as an example.

By the beginning of the Paleozoic era, two rigid masses of the earth's crust were located within this territory: the Russian and Siberian platforms with their most rigid parts, shields. As a result of repeated epochs of folding and mountain building, the yielding zones (geosynclinal belts) located between these platforms, filled with thick strata of deposits, crumpled into folds and turned into mountain structures that adjoined the outskirts of the platforms or connected the platforms with each other. This process can be clearly traced in the history of the Ural-Tyan-Shan geosyncline. At the beginning of the Paleozoic era, thick sediments accumulated near the southern edge of the Siberian platform

and mountain building took place (the Caledonian era of folding), as a result of which mountains arose in the region of the modern Baikal region, in the Sayan Mountains, in the Altai. For the rest of the geosynclinal belt, this epoch was expressed as a preliminary one, since the mountains that emerged here quickly collapsed and were again largely flooded by the sea (Kazakhstan, Western Altai, etc.). On the outskirts of the emerging mountainous countries, in actively sagging areas of the not yet closed parts of the geosyncline, the accumulation of new sediment strata continued, culminating in a new folding and mountain building that developed at the end of the Paleozoic era (the Hercynian era). Vast mountainous countries were formed: the Urals, Tien Shan, the Kazakh mountainous country and mountains on the site of a significant part of the West Siberian lowland. The further history of these mountainous countries is different. Most of them were destroyed by denudation agents, experienced subsidence and are currently under a thick layer of Meso-Cenozoic sediments that compose the sedimentary cover of the West Siberian Lowland. The western marginal part, which has experienced minor uplifts as a result of recent movements, stretches along the edge of the Russian platform in the form of low Ural mountains. Significant areas of an ancient mountainous country, heavily destroyed by agents of denudation, which did not experience significant uplifts and subsidences, are observed in Central Kazakhstan. The southernmost parts of the ancient mountainous country, once already destroyed to a state of shallow hills and later under the influence of powerful mountain-forming movements of the Alpine folding, were broken into boulders and raised to a great height, which led to the formation of the mountainous relief of the Tien Shan.

The given example indicates that the earth's crust, developing according to a general plan from a compliant geosyncline, through a mountain structure to a rigid platform with a flat relief. in different parts it achieves this in different ways. These paths are often clearly reflected in the relief and can explain its diversity.

GEOLOGICAL MAPS AND PROFILES General information about geological maps

Among the maps reflecting natural phenomena, one of the first places is occupied by geological maps created as a result of geological surveys. A geological map gives an idea of the geological structure of an area of the earth's surface and is essentially a vertical projection of outcrops of bedrocks, plotted on a topographic base of a certain scale. Such a map is called a geological map itself, since it is based on the principle of identifying rock strata of different ages.

The geological map is the basis for all other maps compiled in complex geological mapping. The latter provides for the compilation of a number of maps highlighting individual aspects of the geological structure of the region. The marked complex of maps includes: lithological-petrographic, structural-tectonic, hydrogeological, facies-paleogeographic, geomorphological, engineering-geological, various geophysical, mineral resources.

Depending on the scale, all geological maps are divided into overview, regional medium-scale and large-scale.

Overview maps highlight the structure of individual continents and states. The largest scale is 1: 1,000,000. The topographic base is simplified.

Regional maps (small-scale) - display a section of the earth's surface, characterized by the unity of the geological structure (Caucasus, Ural, Donbass, etc.). The scale of the maps is from 1: 1,000,000 to 1: 200,000. The topographic base is simplified.

Medium-scale - detail the geology of a relatively small area. Their scale is from 1: 200,000 to 1: 25,000. The topographic base is simplified.

Large-scale geological maps - compiled for mineral deposits. Scales from 1: 1000 to 1: 500. The topographic base is often compiled on purpose.

Geological work in the field usually begins with reconnaissance routes, which make it possible to get a general idea of the area and identify the features of its individual parts. After reconnaissance, the plan of field work and research is specified, time is allocated and the sequence of routes is outlined. At the same time, the degree of exposure of the area is of great importance, which can be judged with a sufficient degree of reliability from aerial photographs.

The most complete ones - reference outcrops (sections) or wells with continuous coring (samples of rocks obtained from wells during drilling) - are subjected to the first study. Intermediate outcrops, in which only parts of the main section are exposed, are explored later.

Simultaneously with the description of natural and artificial sections, the altitude and planar binding of the marked (reference) layers and horizons, which are important for the mutual coordination of marking (reference) layers and horizons, is carried out. Depending on the scale of the survey, the binding can be instrumental or visual. When describing the stratigraphic sequence of layers in the sections, their thickness and occurrence elements are necessarily measured. As a result, a summary section (column) is drawn up.

Comparison of sections and tracing throughout the area of the region of the identified stratigraphic units make it possible

to get an idea of their structure (forms of occurrence) and facies changes. Binding the outputs of these layers to the earth's surface allows you to draw on the topographic map the contours of the age boundaries of bedrock (pre-Quaternary) rocks - to create a geological map.

Geological maps proper

The method of drawing up a geological map depends on the scale of the survey, exposure and mainly on the geological structure of the area. With a horizontal, inclined and folded bedding, it is different.

The horizontal occurrence is characterized by a close value of the absolute heights of the top or bottom of the layer. Depending on the depth of dissection of the mapped terrain, when lying horizontally on the surface, either only the upper layer (with shallow dissection) or deeper layers (with deep dissection) will be exposed. The horizontal bedding of the layers is easily determined by the coincidence or almost parallel arrangement of the outlets of the mapped layer and the contours of the topographic base (Fig. 29).

If the layers are removed from their original horizontal position and have acquired an inclination to one side, then their occurrence is called monoclinal (one-inclined). To determine the position of monoclinal layers in space, the method of finding the lines of strike and fall of layers is used. A straight line, which is obtained when a monoclinal bed is crossed by a horizontal plane, is called a strike line (Fig. 30). The dip line is located perpendicular to the strike line, directed towards the greatest inclination of the layer. Determination of the occurrence elements, orientation of the lines of strike and fall along the cardinal points is carried out using a mountain compass.

As mentioned above, with a horizontal occurrence, the lines of the layer outlets will coincide with the contours of the topographic map or be parallel to them. With vertical bedding, the terrain relief will not affect the configuration of the lines of intersection of the layer with a plane, since all strike lines are projected in this case on a plane in one line, which will be straight with a straight vertical layer and a curve with a curved vertical surface.

In addition to the two extreme cases of the image on the projection plane of horizontally and vertically lying layers, there can be an infinite number of options for projections of obliquely lying layers, and their configuration will be in direct proportion to the angle of incidence and the terrain. With a highly dissected topography and a gentle dip of layers, the outcropping of the formation will have a more complex contour than with a steep bedding of layers and a slight

boom dismemberment of the relief. The direction of falling of inclined layers on geological maps is determined by their age sequence. The slope will always be towards the location of the younger deposits (Fig. 31).

The folded forms of bedding of the layers significantly complicate the drawing of the geological map. Outputs of the selected age divisions are arranged in stripes, closed by rounded or elliptical contours. Layers of the same age within the fold are always located symmetrically with respect to the central (axial) part of it, which does not have a paired outlet. When reading geological maps depicting a folded structure, first of all, it is necessary to determine the age ratios of layers in order to establish the position of symmetrically located strips of ancient and young layers in relation to the central non-paired stripe. The position of the latter determines the presence of the axial part of the anticline or syncline. In the core of the anticline, older layers always emerge, bordered by outcrops of layers of younger deposits. In contrast, the syncline core contains younger layers surrounded by older ones (Fig. 32).

Tectonic faults on a geological map are depicted by lines that break geological boundaries. The image of displacements of age boundaries in plan and the configuration of the lines of breaks depend on the type of structure, the angles of incidence of the layers, the angle of inclination of the ejector and other reasons.

Geological mapping of igneous rocks takes into account the relationship of the latter with the host strata. Inter-

The ratios of intrusions are presented in different ways when studying intrusive rocks that have penetrated into the sedimentary strata of the earth's crust and are exposed as a result of denudation processes and igneous rocks formed on the earth's surface as a result of volcanic processes. Geological maps show the contour of the outcropping of magmatic bodies and indicate their age and geological composition with the help of indices.

When compiling geological maps, established conventional symbols of three types are used: color; indexes (alphabetic and numeric); dashed.

Colored legend identifies the age of the rocks, and when depicting intrusion outcrops, their composition. Indices - determine the age of the identified units and sometimes their origin (indices of intrusions and effusions). Dashed symbols can replace colors or, when applied to a colored background, indicate the composition of rocks. The standards of color conventions for the subdivision of the geochronological scale were proposed by the Russian geologist A.P. Karpinsky and approved in 1881 by the II International Geological Congress.

In the geochronological scale, two types of subdivisions are used. Some correspond to the time interval of the allocated unit, others - thicker than the rocks formed at this time. Accordingly, the era is parallelized with the group, the period with the system, the era with the department, the century with the tier, and time with the zone.

Color coding standards are adopted for period systems.

Anthropogenous period, system - light gray color

Neogene "" -yellow

Paleogene "" -orange

Cretaceous "" -green

Jurassic "" -blue

Triassic "" -violet

Perm "" - brown-red

Coal "" -gray

Devonian "" -brown

Silurian "" - olive light

Ordovician "" - olive dark

Cambrian "" - pink

Outcrops of rocks of the Archean (AR) and Proterozoic (PR) ages are indicated by different shades of red (large-scale maps of the sites of the indicated age are colored with the colors and strokes adopted for igneous rocks and formations). More fractional subdivisions of the geochronological scale (divisions, tiers, etc.) are painted over with tones of the main color of the period (system), and the density of tone weakens from ancient to young subdivisions.

When compiling a geological map on a scale larger than 1: 100,000, the standard color scale may not be enough. In this case, symbols are added in the form of specks, stripes and others, but in the colors adopted for this period (system).

Igneous rocks are indicated in bright colors with indices corresponding to the name of the rocks. Acidic and intermediate rocks are indicated in red, alkaline rocks in orange, basic rocks in green, and ultrabasic rocks in purple.

The effusive rocks on the maps of the old edition were marked with different colors with indices, put down in accordance with the composition of the rocks. Sour effusive materials were colored orange, basic ones - green. On the maps of the latest editions, effusive rocks are painted over with a color showing their age, with the addition of indices and strokes that determine the composition of the rocks.

The system (period) index is used as the basis for the letter and numerical designation of sedimentary, igneous and metamorphic rocks in the geochronological scale and on the geological map. To it, when designating a department, a number is added corresponding to the lower, middle, upper departments (eras), or when dividing into two parts - lower and upper. When a department (epoch) is subdivided into tiers (centuries), letter designations are added to the index of the department (epoch), consisting of the first letter of the tier name and the first consonant letter in this name. The above can be illustrated by the example of the Cretaceous system (period) index: the system (period) index - (K), the indexes of the divisions (epochs) - (K 1) and (K 2), the index of one of the tiers (centuries) - Valanginian - TO 1 v. Parts

tiers are indicated in Arabic numerals, put down at the bottom right at the index - TO 1 v 1 .

On detailed geological maps, in the upper right, above the index of the period (system), indices are sometimes put down, denoting the facies composition of rocks: T- marine sediments, J- lake, h- coal-bearing, f- flysch *.

In addition to age, it is often necessary to identify local subdivisions that correspond to certain stages of the geological development of a given area. In this case, the rocks are divided into series, formations, subformations, horizons. Whenever possible, local divisions are linked to a generally accepted age scale. Local subdivision indices are formed from two lowercase Latin letters (the first letter of the name and the nearest consonant). Letters are written to the right of the group, system or department index. For example: J 1 bg- Lower Jurassic section, Begitinskaya suite.

For a subdivision that covers two adjacent departments or systems, the index is formed by connecting them with a + (plus) sign or a dash - (hyphen). The + sign is placed if two neighboring subdivisions are combined, represented in their full development J + K; the dash (hyphen) is used in all other cases. The J-K index indicates the presence of the Cretaceous and Jurassic contact in the distinguished unit without determining their more precise age boundaries.

On geological maps, in the case of replacing color designations with dashed ones, the latter are selected arbitrarily. When depicting the composition of rocks, dashed symbols have a certain standard.

A geological section is an image of the sequence of bedding and the structure of layers of the surface parts of the earth's crust in a vertical section. When constructing a section with any occurrence of layers, its horizontal scale must correspond to the scale of the map. The choice of vertical scale depends on the thickness of the layers. The thinnest layer at the selected scale should not be less than 1 mm. Ideally, the vertical scale should be equal to the horizontal scale. In this case, there will be no distortions in the angles of incidence and powers on the profile.

When the layers are inclined and folded, it is necessary to take into account the direction of the profile section in relation to the strike line of the inclined and folded layers; to eliminate distortion of the angles, an amendment must be introduced calculated according to special tables.

With the horizontal bedding of the layers, the section will be the most complete, the line of which passes through the highest and lowest points of the relief. To build a horizontal section

* Flysch - powerful, uniform and rhythmic in structure sedimentary masses of shallow marine sediments.

layers on the geological map, the intersection of geological boundaries with the profile line on the map should be transferred to the profile of the terrain and the resulting points should be connected with horizontal lines.

When constructing a geological section with an inclined bedding of layers, it must be remembered that a section built in the direction of the fall, with equal vertical and horizontal scales, will always have the true angle of inclination of the layers and thickness. In the case when the cut is in the direction of strike, the layers are in a horizontal position.

When constructing a profile section on a geological map, reflecting the folded bedding of layers, as well as with horizontal and inclined bedding, first of all, a topographic profile is built on the scale adopted for vertical constructions. Outputs of geological boundaries and angles of incidence on the wings of the folds are plotted on the topographic profile. Then a geological section is drawn taking into account the position of the axial surfaces of the folds in the plan.

Compilation of profile sections crossing the territory with outcrops of intersecting intrusions requires solving problems that are not considered in the program of this book. In the general case, when the section passes through an intrusion, it should be shown as a body that interrupts the bedding of layers in the same way as in case of faults.

Engineering-geological maps

Geotechnical maps reflect the geotechnical conditions of the mapped area and provide a comprehensive natural assessment required for construction. The task of engineering geology is to determine the geological features of the study area in order to establish its suitability for the construction and operation of engineering structures.

Geological structure influences site selection, layout, structure and construction methods.

The geotechnical map, together with profile sections, stratigraphic columns and a comprehensive characterization of soils, is the main document obtained as a result of geotechnical surveys. General overview, special overview, schematic and detailed maps are usually distinguished among engineering-geological maps for various purposes. General overview maps are used for the design of various types of construction and are drawn up on a small scale (1: 200,000 and smaller). The remaining categories of karg are used for the design of a specific type of engineering structures and are compiled on a scale that meets the requirements of construction.

When engineering and geological surveys and drawing up a map, the nature of the relief, the geological structure

tour, composition of rocks, hydrogeological conditions and dynamics of modern processes. Information about the relief is necessary for selecting a construction site, assessing the volume of earthworks, laying access roads and other design data. The geological structure gives an idea of the occurrence of bedrocks and the position of their roof in relation to the modern hydrographic network. The composition of rocks (soil conditions) is subject to especially careful study and is depicted on the map in accordance with the established geological and petrographic classification.

The study of water content is essential. On the maps, conventional signs indicate the depth of groundwater, water abundance, head, chemical characteristics. In some cases (on large-scale maps), the groundwater surface is depicted by isolines. The dynamics of modern geological processes is reflected on large-scale maps by conventional signs and boundaries that outline the areas on which certain processes develop (landslides, karst, permafrost, subsidence of rocks, various forms of erosion, etc.). The qualitative and quantitative assessment of dynamic processes is marked on the maps, the intensity of the development of the process is indicated.

When preparing an engineering-geological map, it is essential to select colors and conventional signs that determine its clarity and ease of reading.

Tectonic maps

Structural elements of various scales, categories and ages are depicted on tectonic maps.

Drawing up tectonic maps is one of the most important and active methods of studying and analyzing the development of the structures of the earth's crust. Depending on the size of the territory on which the map is drawn up, scale and symbols, it is customary to distinguish between general (summary) and regional tectonic maps. In addition, so-called structural maps are drawn up to display the morphology of tectonic structures. General tectonic maps depict large-scale structural elements, which are the main structures of the earth's crust. Symbols (legend) used in the preparation of such maps are common to the entire surface of the Earth and can be used in any of its regions. Regional maps reflect the structure of a particular area of the earth's crust; the conventions adopted for it may be of little use for using them when drawing up a map of another area.

The relief of the surface of a particular structure, depicted on a tectonic map, is transmitted using isolines (contour lines) connecting points with equal values of occurrence marks, calculated from the level of the World Ocean.

The starting point for general tectonic mapping is to establish the age of folding of the main structures,

the time of formation of the geosyncline, i.e., in time

endings geosynclinal and early platform stages of development of the study area. The moment of transformation of the geosynclinal folded system into a platform is a natural boundary in the development of the earth's crust.

Within Europe and neighboring parts of other continents, territories are distinguished that have survived the following main folding epochs, the age of which is determined by the time of completion of the geosynclinal stage of development: Precambrian (Archean and Proterozoic), Baikal, Caledonian, Hercynian and Alpine. Larger subdivisions (cycles) in the development of the earth's crust, uniting many eras and periods (stages) of folding, are called megachrons. In the history of the formation of the earth's crust, several megachrons can be distinguished, but the most studied is the last one, which received the name neog ey. In this new, last, megachron, a radical restructuring of the earth's crust and the formation of its modern structure took place. The age of these structures is reflected on tectonic maps with special indices and colors.

On the tectonic maps of the territory of the USSR, blue is adopted for the Baikal folding (Proterozoic), purple for the Caledonian, brown for the Hercynian (Variscian), and yellow for the Alpine. Older megachrons are shown in shades of red.

When depicting different zones of geosynclinal areas - eugeosynclines and myogeosynclines, shades of colors are used that determine the age of a particular folded structure and an alphabetic index is put. For example, the eugeosyn-clinal zone of the Caledonian folding is denoted by the index - еС. Structural floors in folded structures are also distinguished with the help of the tone density of the accepted age color, while the lower structural floors are painted over with a more intense shade. Letter indices are supplemented with numbers. K 1, for example, denotes the lower level of the Karelian folding (Proterozoic), C 2 - the middle level of the Caledonian folding, A 3 - the upper structural level of the Alpine folding, etc. There are alphabetic and numeric designations for more fractional subdivisions - sublevels. For example, A 2 1 is the upper sublevel of the lower structural level of alpine folding.

Marginal deflections are indicated by a banded horizontal coloration of the color of the upper structural level of the given folding. In the case of overlapping the edge deflection by the platform cover, translucent shading is used under the paint of the platform cover. Internal intermontane depressions, which develop simultaneously with the marginal troughs, are indicated by the color of the upper structural floor with a speck of molasse *. The middle arrays are painted over

* Molasses - clastic rocks filling deep depressions of geosynclinal zones v the main eras of mountain building.

are formed by the color of folding, which turned them into rigid blocks (for example, the Hercynian massifs among the structures of alpine folding in the Caucasus, etc.).

With the introduction into the legend of general tectonic maps of designations of eu- and myogeosynclines, structural levels and internal depressions, with appropriate detail of the contours, these maps raise their accuracy to the level of regional maps.

Within the platform structures, on general tectonic maps, areas of outcrops to the surface of the folded basement (shields) and slabs are distinguished, on the area of which the basement is covered by a sedimentary cover. On the shields and exposed vaults of the anteclises, the folded basement is dismembered, respectively, with the epochs of folding, with the allocation of structural floors. On the territory of the slabs, the surface of the folded foundation is depicted using isohypsum and stepped coloring, shading the areas of subsidence and uplifts. (Submerged areas are lighter than raised areas.) The age of the platforms is emphasized on tectonic maps in a certain color, which differs from the folded areas in a paler tone. To designate the sedimentary cover of the platforms, the following color tones are adopted: the sedimentary cover of the ancient platforms is indicated by a brownish-pink color, the Epicaledonian ones are purple-green, and the Hercynian ones are brownish-gray.

Outcrops to the surface of intrusive massifs are depicted in the same way as on geological maps, within the limits of their modern erosional section. Intrusions are subdivided according to their belonging to certain stages of tectogenesis (early orogenic, late orogenic and anorogenic). The age of the intrusions is indicated by indices, the composition - by the color and icons adopted for geological maps.

Large faults are depicted on general tectonic maps by solid and dashed red lines. In addition, tectonic maps show zones of intensive development of metamorphism and centers of modern and ancient volcanism.

Symbols have been developed in great detail to denote folded and ruptured faults displayed on tectonic maps, as well as to denote boundaries and lines dividing structures of various orders and ages.

The Cenozoic era is the last one known today. This is a new period of life on Earth, which began 67 million years ago and continues to this day.

In the Cenozoic, the sea transgressions stopped, the water level rose and stabilized. The modern mountain systems and relief were formed. Animals and plants have acquired modern features and have spread everywhere on all continents.

The Cenozoic era is divided into the following periods:

Paleogene;
neogene;
anthropogenic.

Geological changes

At the beginning of the Paleogene period, the Cenozoic folding began, that is, the formation of new mountain systems, landscapes, and reliefs. Tectonic processes took place intensively within the Pacific Ocean and the Mediterranean Sea.

Mountain systems of Cenozoic folding:

Andes (in South America);
Alps (Europe);
Caucasus Mountains;
Carpathians;
Middle Ridge (Asia);
Partially Himalayas;
Mountains of the Cordillera.

Due to the global movements of vertical and horizontal lithospheric plates, they have acquired a form corresponding to the current continents and oceans.

Cenozoic climate

The weather conditions were favorable, the warm climate with periodic rains promoted the development of life on Earth. Compared to today's average annual rates, the temperature of those times was 9 degrees higher. In hot climates, crocodiles, lizards, turtles adapted to life, which were protected from the scorching sun by developed outer covers.

At the end of the Paleogene period, a gradual decrease in temperature was observed, due to a decrease in the concentration of carbon dioxide in the atmospheric air, an increase in the land area due to a drop in sea level. This led to glaciation in Antarctica, starting from the mountain peaks, gradually the entire territory was covered with ice.

Fauna of the Cenozoic era

At the beginning of the era, cloacal, marsupials and the first placental mammals were ubiquitous. They could easily adapt to changes in the external environment and quickly took over the water and air as well.

Bony fishes have settled in the seas and rivers, birds have expanded their habitat. New species of foraminifera, molluscs, and echinoderms have formed.

The development of life in the Cenozoic era was not a monotonous process, jumps in temperature, periods of severe frost led to the extinction of many species. For example, mammoths that lived during the glaciation period could not survive to our times.

Paleogene

In the Cenozoic era, insects made a significant leap in evolution. While mastering new areas, they experienced a number of adaptive changes:

We got a variety of colors, sizes and body shapes;
got modified limbs;
species with complete and incomplete metamorphosis appeared.

Mammals of enormous size lived on land. For example, the hornless rhinoceros is indricotherium. They reached a height of about 5m and a length of 8m. They are herbivores with massive three-toed limbs, a long neck and a small head - the largest mammals ever to live on land.

At the beginning of the Cenozoic era, insectivores split into two groups and evolved in two different directions. One group began to lead a predatory lifestyle and became the ancestor of modern predators. The other part ate plants and gave rise to hoofed animals.

Life in the Cenozoic in South America and Australia had its own characteristics. These continents were the first to separate from the continent of Gondwana, so the evolution here went differently. For a long time, the mainland was inhabited by primitive mammals: marsupials and monotremes.

Neogene

In the Neogene period, the first humanoid apes appeared. After a cold snap and a decrease in forests, some became extinct, and some adapted to life in open areas. Soon, primates evolved into primitive humans. This is how it began anthropogenic period.

The development of the human race was rapid. People begin to use tools for food, create primitive weapons for protection from predators, build huts, grow plants, tame animals.

The Neogene period of the Cenozoic was favorable for the development of oceanic animals. Cephalopods - cuttlefish, octopuses, which have survived to this day, began to multiply especially quickly. The remains of oysters and scallops were found among bivalve molluscs. Small crustaceans and echinoderms and sea urchins were found everywhere.

The flora of the Cenozoic era

In the Cenozoic, the dominant place among plants was taken by angiosperms, the number of species of which significantly increased in the Paleogene and Neogene periods. The distribution of angiosperms was of great importance in the evolution of mammals. Primates might not have appeared at all, since flowering plants are the main food for them: fruits, berries.

Conifers developed, but their numbers decreased significantly. The hot climate contributed to the spread of plants in the northern regions. Even beyond the Arctic Circle, there were plants from the Magnolia and Beech families.

On the territory of Europe and Asia, camphor cinnamon, figs, plane trees and other plants grew. In the middle of the era, the climate changes, cold weather sets in, displacing plants to the south. The center of Europe, with a warm and humid environment, has become a great place for deciduous forests. Representatives of plants from the Beech family (chestnuts, oaks) and Birch trees (hornbeam, alder, hazel) grew here. Closer to the north, coniferous forests with pines and yews grew.

After the establishment of stable climatic zones, with lower temperatures and periodically changing seasons, the flora has undergone significant changes. Evergreen tropical plants have been replaced by species with falling leaves. The family Zlakovye stood out as a separate group among monocotyledons.

Huge territories were occupied by steppe and forest-steppe zones, the number of forests was sharply reduced, and herbaceous plants developed mainly.

Cenozoic or cenozoic era- the last at the moment era of the geological history of the Earth. The Cenozoic era continues today. It began 66 million years ago, immediately after, as a result of which all dinosaurs disappeared. It is not known when the new era will come. In order for the Cenozoic era to be replaced by a new era, significant changes must occur in the geological conditions of the planet. In order not to get confused in eras and periods, use for clarity.

Cenozoic periods

The Cenozoic is divided into three periods and seven eras (divisions).

1. or the Paleogene period. It lasted from 66 million years ago to 23 million years ago. It is divided into three eras: Paleocene, Eocene, Oligocene.

2. or Neogene period. It lasted from 23 to 2.5 million years ago. It is divided into two eras: Miocene and Pliocene.

3. or Anthropogen. It began 2.5 million years ago and continues to this day. It is divided into two eras: Pleistocene and Holocene.

Life in the Cenozoic

Life in the new era has changed dramatically after the mass extinction. The Cretaceous-Paleogene extinction literally changed the face of the animal kingdom beyond recognition. If in the Mesozoic the rulers of the Earth were giant dinosaur lizards, then in the Cenozoic mammals took their place. After the catastrophe that occurred 66 million years ago, many animals became extinct. The greatest survival rate was found in warm-blooded mammals. They associate this with the fact that as a result of a global cooling due to a giant meteorite hitting the ground, all cold-blooded people who depend on the ambient temperature simply froze.

Warm-blooded, which are able to maintain the temperature of the body, were able to survive the catastrophe, and when all the consequences of the impact of the meteorite on the ground passed, they found themselves in a completely new world. All dinosaurs that occupied the main life niches became extinct completely. Only lizards, snakes, crocodiles and other small animals remained from the reptiles. This gave warm-blooded people endless freedom for development. For 66 million years, warm-blooded animals have received a gigantic variety. In addition, small reptiles, fish, marine animals, birds, insects, and plants also received a great variety. Also, at the end of the Cenozoic, an absolutely new form of life appeared, which changed the entire appearance and way of planet Earth - Homo sapiens.

Cenozoic era documentary:

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Quaternary period (anthropogen)

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Quaternary period (anthropogen) originates from 2.6 million liters. n. and continues to this day. During the time that this time period lasts, three main things have happened:

the planet entered a new ice age, during which sharp cold snaps alternated with warming;
the continents assumed their final present outlines, the modern relief was formed;
Homo sapiens appeared on the planet.

Anthropogen subdivisions, geological changes, climate

Almost the entire length of the anthropogen is occupied by the Pleistocene division, which, according to international stratigraphic standards, is usually divided into the Gelazian, Calabrian, Middle and Upper stages, and the Holocene, which originates a little more than 11 thousand years ago. n. and continuing to this day.

Basically, the continents in their present form were formed long before the beginning of the Quaternary period, but it was during this period of time that many young mountain ranges acquired their present appearance. The coastline of the continents took on the current outlines, and due to the alternately advancing and retreating glaciers, the extreme northern continental archipelagos were formed, such as the Canadian, Spitsbergen Islands, Iceland, Novaya Zemlya, etc. 100 meters.

Retreating, the giant anthropogenic glaciers left a trail of deep moraines in their wake. During the periods of maximum glaciation, the total area of glaciers exceeded the current ones by more than three times. Thus, it can be said that large parts of North America, Europe and present-day Russia were buried under ice strata.

It is worth saying that the current ice age is not the first in the history of the earth. For several billion years, the first historical ice age lasted, beginning with 1.5 billion years. n. in the early Proterozoic. After prolonged heat, a 270-million-year cold snap hit the planet again. It happened 900 million liters. n. in the late Proterozoic. Then another significant icing took place, lasting over 230 million liters. n. in the Paleozoic (460 - 230 million years ago). And now the planet is experiencing another cold snap, the beginning of which is usually attributed to 65 million years ago. It gradually gained strength and it is not yet known whether the Cenozoic global ice age survived its apogee of low temperatures.

Rice. 1 - Anthropogen (Quaternary)

During the current ice age, there has been a great many warming and cooling, and according to scientists, in this period of time the Earth is experiencing a warming stage. According to their calculations, the last cold snap was replaced by a warming from 15 to 10 thousand years ago. During the strongest glaciations of the Pleistocene, the line of glaciers dropped from 1500 to 1700 km south of the present line.

Anthropogen climate was subject to repeated fluctuations. In those times when glaciers were advancing, climatic zones narrowed and retreated closer to the equator, and, conversely, during periods of warming and massive melting of glaciers, the temperate zone spread to the northernmost continental margins and, as a result, other climatic zones also widened.

Quaternary sedimentation

On Quaternary sedimentation the rapid variability of lithological components and genesis left its mark. Sediments in the Quaternary period accumulated everywhere, but due to the complex structure of the sections, it is rather difficult to distinguish them. The accumulation rate of anthropogenous sediments was too high, but due to the lack of pressure, the sediments still have a rather loose structure. The bedding conditions are also atypical. If sequential bedding is considered typical, then the term "leaning" to lower and older deposits is more appropriate here. Continental deposits, such as glacial, aquatic, and aeolian, are more characteristic of continental zones. For the seas, volcanic, organogenic, trigenous, and chemogenic sediments are more typical.

Quaternary animals

Among invertebrates in the Pleistocene of the Quaternary period, all kinds of snails and other land mollusks developed extraordinarily. The underwater world was in many ways similar to the previous Neogene. The world of insects also began to acquire a resemblance to the present, but the world of mammals was subject to the most interesting metamorphoses.

Since the beginning of the anthropogen, varieties of elephants have become widespread. At the beginning of the Pleistocene, they inhabited vast territories of the Eurasian continent. Some of their species reached a height of 4 m at the withers. Increasingly, species of elephants covered with long hair began to appear in the northern parts of the continents. By the middle of the Pleistocene, mammoths were already the most common and most widespread representatives of the northern tundra latitudes. Having migrated across the ice of the Bering Strait in one of the next segments of the cold snap to Alaska, mammoths have multiplied throughout the entire part of the North American continent. Mammoths are believed to have evolved from the trogontery elephants, on the border of the Neogene and Pleistocene, widespread in the steppe latitudes.

In the southern latitudes of both North America and Eurasia, other species of elephants were widespread. Among others, the giant mastodons stood out. What is characteristic, these representatives of elephants on the territory of the Eurasian continent completely died out by the end of the Pleistocene, while on the American continent they safely survived all stages of the glaciation of the Earth.

Among other giants of the Quaternary period, rhinos also stood out. Their woolly varieties inhabited the tundra-steppe of the Early and Middle Anthropogen, along with mammoths.

Were numerous Quaternary animals from the category of horses. Tellingly, the ancient descendant of horses came from the North American part of Pangea. After the split of the continent and the cessation of the migration of animals between the American and Eurasian segments, the equines became completely extinct on the North American continent, and only those species that managed to migrate to the Eurasian continent evolved. Subsequently, they reappeared in America only thanks to man.

Along with equines, which inhabited the European-Asian savannas in large numbers, hippos were also active during periods of anthropogenic warming. Their remains have been found in large numbers on the islands of Great Britain. There were also numerous artiodactyl species of deer, the most common of which was the Irish big-horned deer. In span, its horns sometimes reached up to 3 meters.

In the Quaternary period, the first goats appeared, among which the mountain varieties were the most numerous. The first rounds appeared, the progenitors of domestic bulls. Huge pastures of all kinds of roe deer, bison, musk oxen grazed on the steppe expanses; the first varieties of camel appeared to the south.

Also, along with herbivores, a detachment of predators also developed. For example, a variety of bears could be found both in snow-covered areas of northern latitudes and in tundra forests. Many of them lived to the south, going down to the steppe strip of temperate latitudes. Many of them, inhabiting the caves of the glacial Pleistocene, could not survive in the cold conditions of the Arctic at that time, but, one way or another, many of their species have survived safely to this day.

There were numerous in the northern regions such deadly anthropogenous predators(Fig. 2), like saber-toothed tigers, and cave lions, which were much more massive and larger and more dangerous than their modern relatives. Often these dangerous predators became the themes of the works of ancient rock artists.

Rice. 2 - Predators of the Quaternary period

Also among others fauna of the Quaternary period also represented various other species, such as hyenas, wolves, foxes, raccoons, wolverines, etc. There was also a large number of rodents such as lemmings, ground squirrels, beavers of various species, up to the giant Trognotherium cuvieri.

The kingdom of birds was also very diverse, among which both flying and flightless species stood out.

By the end of the Pleistocene, many species of mammals that had previously inhabited the tundra steppe became extinct. To such Quaternary mammals can be attributed:

on the territory of South America - the armadillo teticurus, the giant saber-toothed cat smilodon, hoofed macrouchenias, sloths of megatherium, etc .;
on the territory of North America - the last representatives of tyrant birds or fororakos - Waller's titanis, many representatives of ungulates, such as American horses, camels, steppe bakers, deer, bulls and pronghorns;
on the territory of the tundra-steppes of Eurasia, Alaska and Canada - mammoths, woolly rhinos, big-horned deer, cave lions and bears.

In the Holocene, such avian flightless species as dodo and apyornis died out, and a giant seal-like stellar cow disappeared from the depths of the sea.

Anthropogenous plants

The Pleistocene climate with constant alternation of glacial and interglacial gaps had an adverse effect on anthropogen plants that grew in northern continental latitudes. The climatic life barrier with the onset of cold snaps was sometimes forced to shift to the line of 40 ° N. sh., and in some places even lower. Over the past two and a half million years, vegetation has been forced to alternately retreat to the above latitudes, then grow again up to the shores of the Arctic Ocean. As a result of the cold snap, many thermophilic plants, which have been descending since the Triassic times, were doomed to extinction. With the disappearance of many varieties of grasses, shrubs and other plants, the extinction of many species of anthropogenous animals is also associated. Therefore, one should not place all the blame for the extinction of such species as the mammoth, entirely on the shoulders of ancient people.

In the glacial epochs of the Quaternary period, to the south of the tip of the glaciers, three bands of vegetation took on existence - tundra, steppe and taiga. The tundra was covered with mosses and lichens; dwarf birches, polar willows, and Alpine silverlings began to grow to the south. For the tundra, azaleas, stone-breakers, chippings, etc. were also typical. The steppe zone was full of all kinds of grasses and low shrubs. But closer to the south, in some places, there were woods, consisting of willow and birch forests. Anthropogenic taiga forests were composed mainly of pines and spruces, which, closer to the south, mixed with birches, aspens and other deciduous deciduous trees.

During the interglacial epochs, the composition of the flora of the Quaternary period changed significantly. Driven to the south by glaciers, thickets of flowers and shrubs such as lilies, rhododendrons and roses returned to their places. But little by little, as the Holocene approached, the interglacial vegetation became increasingly scarce due to constant forced migrations. Many walnut and yew trees, which formed huge forest tracts earlier, have become rare now. In the warmest intervals of interglacials, the Central European territory was completely covered with deciduous forests, consisting of oak, beech, lime, maple, hornbeam, ash, hawthorn and some walnut trees.

In places where interglacial plant migrations were not hindered by mountain ranges and seas, specimens of ancient vegetation from the Triassic period have nevertheless been preserved. For example, in North America, where migrations were not difficult as in the case of the mountain ranges of Europe, as well as the Mediterranean Sea, magnolias, liliodendrons, taxodiums and Weymouth pines (Pinus strobus) still grow in some areas.

Much to the south, the vegetation did not undergo any definite differences from the previous Neogene period.

The ancestors of modern people appeared at the end of the Neogene 5 million years ago. n. They were descended from one of the branches of hominids australopithecines, and their remains were found only on the African continent, which gives reason to say that the ancestral home of all mankind is precisely Africa. The warm climate and lush vegetation of these places contributed to the increasing evolutionary development of the Australopithecus, until, finally, the first of them at the turn of the Quaternary period did not master the primitive types of tools. The next branch of the development of a skilled man (Homo habilis) was archanthropus, the direct ancestors of modern people, who in the second half of the Pleistocene began to actively settle across all continents. One of the most famous branches of the Archantropus are pithecanthropus, the remains of which archaeologists find almost everywhere. In the region of 400-350 thousand liters. n. the first transitional forms of ancient people began to appear from archanthropus to paleoanthropus, which include neanderthals who later became extinct, unable to withstand competition from Cro-Magnons... Although, according to some scientists, these two species simply mixed with each other. Further, paleoanthropes developed into neoanthropines, which were no longer different from modern people. It happened in the region of 40-35 thousand liters. n. In particular, the Cro-Magnons were the first representatives of the neoanthropes.

Rice. 3 - Formation of man during the anthropogenous period

Gradually, people mastered more and more complex tools. 13 thousand liters n. bows and arrows appeared, after which people learned how to burn pots and acquired the first objects made of ceramics. They began to engage in agriculture, cattle breeding. 5 thousand liters n. the first items of bronze and copper appeared, and somewhere between 3 and 2.5 thousand years. n. the era of iron began.

Since that time, the improvement of tools of labor has gone much faster, in the Middle Ages the development of science and technology began, which have now reached a level that allowed people to develop such sciences as genetics and genetic engineering.

Quaternary minerals

Quaternary deposits contain many different fossils. Placer deposits within mountain ranges and zones of tectonic activity are rich in gold, diamonds, cassiterite, ilmenite, etc. loam, clay, pebble, sandstone, limestone. There are also numerous accumulations of brown coal, there are deposits of natural gas, diatomites, salts, leguminous iron ores, sapropels, etc. You can also find deposits of sulfur and manganese in volcanic regions. Peat sedimentary accumulations are numerous and ubiquitous.

The layers of the Quaternary period contain a huge amount of fresh groundwater, some thermal springs originate in their depths, and in our time, various medicinal muds formed in the anthropogen are intensively used.