Minerals and their classification
The lithosphere has the following environmental functions:
1) resource (availability of various types of natural resources necessary for biota and humans);
2) geodynamic (the presence of disturbances in the upper parts of the lithosphere due to endo- and exogenous, natural and artificial processes);
3) geochemical (content chemical elements, necessary for biota and humans, as well as the presence of pollutants);
4) geophysical (presence of physical fields).
When considering each function, environmental consequences or mining, or disturbances of the lithosphere, or the accumulation of chemical elements; The influence of physical fields on living organisms is revealed.
Fuel and energy resources
The main minerals include fuel and energy resources, which are used for energy production and as fuel. Fuel and energy resources include oil, hard and brown coal, gas, shale, and uranium. Each type of fuel raw material has a certain calorific value. Calorific value is the amount of energy released when a unit of fuel is burned. Significant calorific value is produced by oil and gas.
Fuel raw materials are unevenly distributed across the globe. North America and Eurasia have the most significant volumes (87% of the total energy potential is concentrated here). The main types of fuel raw materials include oil, gas, and coal.
Oil is the most important and efficient look fuel raw materials. It is characterized by high caloric content and calorific value, low content of polluting compounds. Oil is easily transported and during the refining process it is obtained wide range products.
Oil fields are unevenly distributed around the globe. 62% of the world's total oil reserves are concentrated in the Arabian Peninsula and the Persian Gulf ; 11% of the world's oil reserves are in North America, 7% in Africa and Russia, 9% in South America Promising oil fields are in the shelf zone of seas and oceans, on the continental slope (600-900 m). Offshore fields currently account for 25% of global oil production. Large oil reserves are found in oil sands, oil shale, and bituminous rocks (contain so-called heavy oil). Develop these reserves in industrial scale So far it hasn't been possible. 32% of the world's energy needs are met by oil.
Natural gas is distributed even more unevenly in the bowels of the Earth. Russia ranks first in the world in terms of gaseous fuel resources (fields in Western Siberia). Significant gas deposits are located in the countries of the Near and Middle East (resources are especially large in Iran, Saudi Arabia, in the waters of the Persian Gulf). Less inventories in the US, North Africa, Venezuela. The shelf zones of the World Ocean are promising.
In the world energy balance the share is natural gas accounts for 17%, in a number of countries (USA, Western Europe, Japan) above. Unlike oil, gas potential is increasing faster than production (about 2 times), in addition, more than half of the shelf area has not yet been explored for gas content, and underwater gas fields account for 15% of global gas production. On land, only 30% of tectonic structures promising for this raw material have been studied. Another reserve of this type of fuel resource is gas conservation.
Coal-bearing basins are distributed unevenly across the globe. Russia and neighboring countries, the USA, China and South Africa account for more than 90% of the extractable coal resources. Poland, Germany, Australia, Great Britain and other countries have large reserves.
Until the 60s, coal dominated the structure of the fuel balance (more than 50%). In the 1980s, due to the use of oil and gas, the share of coal decreased (to 28%). Currently, up to 30% of the world's energy was produced from coal (the reason is the instability of the world market).
The globe is not equally supplied with nuclear raw materials. More than 28% of nuclear raw material resources are in the USA and Canada, 23% in Australia, 14% in South Africa, 7% in Brazil. In other countries, uranium reserves are insignificant. Thorium resources are found in India (almost half of the resources), Australia, Brazil, Malaysia and the USA.
Alternative energy sources
Non-traditional energy resources include solar, wind, tidal, geothermal, and bioconversion energy.
The total amount of solar energy is 20 thousand times higher than the current energy consumption of the world economy. Since the density of solar radiation on the land surface is so low (even in tropical deserts during the day it is 5-6 kWh/m2 per day, in temperate deserts it is 3-4 kWh/m2), it is difficult to master technically. Currently in use solar ovens to obtain low-temperature fuel.
Wind energy has long been used in England, Holland, France and other countries, on a small scale. The total wind energy resources are vast but highly localized. In Denmark and other countries of the European North, wind turbines provide at least 12% of energy. However, the technical difficulties in harnessing wind energy are significant.
Tidal energy is actually used at several tidal power plants: in Russia (Kislogubskaya), in France (the mouth of the Garonne). The difficulty in using energy lies in converting the shock force of the wave into gravitational, thermal and electrical forms of energy.
Bioconversion energy is energy accumulated in biomass. Wood has long been used as a source of fuel. There are experimental developments for producing biogas from waste agriculture, but this process has not yet been developed on an industrial scale. Biogas consists of 60-70% methane (with calorific value- 5000 kcal per 1 m 3), while the process of gas release is continuous, and the resulting residue - sludge - is a good fertilizer.
Geothermal energy – internal energy Earth. The normal temperature gradient of the Earth is 3 o C per 100 m depth, in some places up to 5 o C per 100 m. Geothermal power plants operate in Italy, USA, Japan, Iceland, etc. In California, 7% of energy is obtained from hydrothermal sources. The resources of rocks heated by endogenous heat are 20 times greater than the reserves of fossil fuels.
Oil and gas (extracted)
Belarusian oil and associated gas fields are located in the eastern part of the Pripyat trough.
As of 2010, about 75 deposits were discovered and explored, the largest of which are Rechitsa, Ostashkovichskoe and Vishanskoe.
Almost all oil deposits of the fields are confined to Devonian sediments (pre-salt terrigenous, sub-salt carbonate, inter-salt, upper salt Devonian strata), and only 2 deposits - to Upper Proterozoic.
Industrial production began in 1965 and over the entire period more than 115 million tons have been produced. Now annual oil production is 1.5 million tons per year (more than 12 million tons of oil per year are needed for the needs of the republic). The maximum annual production was in 1975 - 8 million tons.
Oil shale(not mined)
Oil shale deposits Belarus - Lyubanskoye and Turovskoye, confined to the post-salt Devonian thicker than the Pripyat trough. Low quality - high ash content.
The forecast resources of oil shale in the Pripyat shale-bearing basin to a depth of 600 m are 11 billion tons, including 5.5 billion tons to a depth of 300 m.
Brown coals (not mined)
Deposits brown coals Belarus were found in sediments of different ages: in Carboniferous, Jurassic, Paleogene and Neogene. However, the greatest value so far is precisely Neogene coals.
In the western part of the Pripyat trough, 3 deposits of Neogene age have been identified: Zhitkovichskoye, Brinevskoye and Tonezhskoye. The depth of occurrence is 20-80 m, which makes it possible to mine coal using the open-pit (quarry) method.
Reserves at these 3 fields are more than 100 million tons.
Peat (mined)
Peat deposits in Belarus distributed almost everywhere, the age of this mineral quaternary.
About 9,200 deposits have been identified in Belarus, containing 3 billion tons of peat. About 400 deposits are exploited, 13-15 million tons are extracted annually. Over all the years of development of peat deposits, 1.1 billion tons of peat have been extracted.
Chemical raw materials of Belarus
Potassium salts (mined)
Potassium salts - the main mineral wealth of Belarus, the most important export product.
They lie in the Pripyat trough and are associated with the lower and upper salt strata of the upper Devonian
Main deposits of potassium salt in Belarus– Starobinskoe(reserves 2.7 billion tons) - under development, Petrikovskoye (reserves 1.28 billion tons) and Oktyabrskoye fields (reserves 637.2 million tons).
The total industrial reserves of potassium salts are more than 5 billion tons; according to this indicator, Belarus ranks 3rd in the world after Canada and Russia.
Industrial production of potassium salt began in 1961; now the annual production of potassium salts in Belarus is about 20 million tons, of which more than 8 million tons of potash fertilizers are produced annually.
Rock salt (mined)
Rock salt is one of the most important minerals in Belarus. Its resources dedicated to Devonian salt strata of the Pripyat trough are practically inexhaustible.
Currently, three largest deposits have been explored: Mozyrskoye, Starobinskoye and Davydovskoye. The first two are in use.
Total reserves are about 22 billion tons.
Dolomites (mined)
Dolomite deposits in Belarus are located in the Orsha depression, confined to Devonian sediments.
Explored and developed dolomite deposit - Ruba (Vitebsk region). The average carbonate content is about 94%.
The deposit is developed by open pit mining (Gralevo quarry). Annual production of 3-4 million tons of dolomite. The main products are dolomite flour for liming acidic soils.
The total proven reserves of the field are 755 million tons.
Phosphorites (not mined)
Phosphorite deposits in Belarus are located in the Orsha depression, confined to Upper Cretaceous sediments.
Explored phosphorite deposits – Mstislavskoye (reserves 175 million tons), Lobkovichskoye (reserves 246 million tons).
Metallic minerals of Belarus
Sands (mined)
Glass sands Belarus has been explored (not yet mined) in the Gomel (Loevskoye) and Brest (Gorodnoye) regions. Their total reserves are 15 million m3. Glass sands are suitable for producing window and container glass.
Molding sands Belarus – Zhlobin and Dobrush districts. Total reserves are 100 million tons. About 0.6 million m3 of foundry sands are mined annually.
Sand and gravel mixtures– north and center of Belarus, 136 fields with total reserves of more than 700 million m 3; 82 deposits are exploited, total reserves are 660 million tons. About 3 million m3 of sand and gravel materials are mined annually. They are mainly used for the preparation of concrete and mortars.
Clays (mined)
The deposits are located in the south of Belarus.
More than 210 deposits of fusible clays have been explored (Vitebsk region) with total reserves of about 200 million m 3. More than 110 deposits are being developed, and 2.5-3.5 million m 3 of raw materials are extracted annually.
Refractory clays are found in the south of Belarus (Luninetsky, Loevsky, Stolinsky districts), about 20 deposits.
Chalk and marl (mined)
Deposits of chalk and marls are located mainly in the east of Belarus, and are found in the west of the country. A number of deposits have been explored in areas of their shallow occurrence, mainly in the Krichevsky, Klimovichsky, Kostyukovichsky and Cherikovsky districts of the Mogilev region, Volkovysk and Grodno districts of the Grodno region. Some of them (for example, Krichevskoye) are represented by writing chalk, others (Kommunarskoye) by marl, and others (Kamenka) by marl and writing chalk.
Total reserves are about 270 million tons.
Gypsum (not mined)
The Brinevskoe gypsum deposit is located in the west of the Pripyat trough and is confined to Upper Devonian sediments.
Gypsum reserves are 400 million tons.
Building stone (mined)
Deposits building stone in Belarus Mikashevichi and Sitnitsa (Brest region), Glushkevichi and Nadezhda Quarry (Gomel region).
At the Mikashevichi deposit (the largest), annual stone production is about 3.5 million m 3, crushed stone production - 5.5 million m 3, at the Glushkevichi deposit - 0.1 million m 3 and 0.2 million m 3, respectively.
Lecture 2.1. General information about lithosphere resources
1. Minerals and their classification
2. Fuel and energy resources
3. Alternative energy sources
4. Mineral resources of Belarus.
Resource function
The resource function of the upper horizons of the lithosphere lies in its potential ability to provide the needs of biota (ecosystems) with abiotic resources, including human needs with certain minerals necessary for the existence and development of human civilization. (Korolev, 1996; Trofimov, Ziling, 2000, 2002).
The resource function is basic in the “lithosphere-biota” system, since it is associated not only with the living conditions and evolution of the biota, but also with the very possibility of its existence.
This function determines the role of resources (mineral, organic, and organomineral) for the life and activity of biota both as a biogeocenosis and social structure. The resource function of the lithosphere determines the importance of mineral, organic and its organomineral raw materials, which form the basis for the life activity of biota both as biogeocenoses and anthropogeocenosis (Yasamanov, 2003).
According to V.T. Trofimova et al. (2000), it includes the following aspects:
· resources necessary for the life and activity of biota,
· resources necessary for the life and activities of human society,
· resources, as the geological space necessary for the settlement and existence of biota, including human society.
The first two aspects are related to mineral resources, and the last one is related to the ecological capacity of the geological space within which the life of the organism occurs.
From the standpoint of biocentrism, human needs should not conflict with the needs of the biota as a whole. Among the natural resources on Earth, energy resources come first in terms of their importance for developed countries. At the current level of industrial development in the world, technological energy creates and transforms a huge amount of energy, if we consider the planet as a whole. About 70% of the world's extracted minerals are energy resources. Consequently, we can talk about the commensurability of technogenic energy potential with the energy potential of the Earth of natural origin, especially in urbanized areas.
Lithosphere resources necessary for the life of biota
They are represented by rocks and minerals, which include chemical elements of the biophilic series, vital for the growth and development of organisms, kudurites - mineral substance Kudurov, which is the mineral food of lithophates. and groundwater. Carbon, oxygen, nitrogen, hydrogen, calcium, phosphorus, sulfur, potassium, sodium and a number of other elements are required by organisms in significant quantities, which is why they are called macrobiogenic. Microbiogenic elements for plants are Fe, Mn, Cu, Zn, B, Si, Mo, C1, V, Ca, ensuring the processes of photosynthesis, nitrogen metabolism and metabolic function.
Animals require the same elements, except boron. They obtain some of them using producers in food, and some from mineral compounds and natural waters. In addition, animals (consumers of the first and second orders) additionally require selenium, chromium, nickel, fluorine, iodine, etc. These elements in small quantities are vital for activity
organisms and perform biogeochemical functions.
Some of the listed elements are in a gaseous state in the atmosphere, others are dissolved in the waters of the hydrosphere or are in a bound state in the soil cover and lithosphere. Plants (producers) extract these elements directly from soils during their life processes along with soil and groundwater.
Mineral substances of kudyurs are episodic food of herbivores (first-order consumers) and omnivores (third-order consumers) animals. They eat them with food at least twice a year. Kudyurs are designed to regulate the salt composition of the body. These are mainly minerals of the zeolite group. In addition to zeolites, clay minerals such as bentonites, palygorskites, as well as glauconite and diatomite are stimulants for the growth of plants, animals and fish.
Groundwater is the basis for the existence of biota and determines the direction and speed of biochemical processes of plants and animals.
Mineral resources necessary for the life and activities of human society
These include all existing minerals that are used humanity for production necessary materials and energy. Currently, more than 200 types of minerals are extracted from the subsoil and the annual production of mineral raw materials reaches about 20 billion tons of rock mass per year.
The most important groups of minerals and the main areas of their use are shown in Fig. 4.
rice. 4.
The ecological significance of groundwater is enormous. The main areas of their use and consumption volumes (km/year) are given below.
65. ECOLOGICAL FUNCTIONS OF THE LITHOSPHERE: RESOURCE, GEODYNAMIC, GEOPHYSICAL-GEOCHEMICAL
Even in ancient times, people learned to use for their needs some of the resources of the lithosphere and other shells of the Earth, which was reflected in the names of the historical periods of human development: “Stone Age”, “Bronze Age”, “Iron Age”. More than 200 are in use today various types resources. All natural resources should be clearly distinguished from natural conditions.
Natural resources- these are the bodies and forces of nature, which at a given level of development of productive forces and knowledge can be used to meet the needs of human society in the form of direct participation in material activity.
Under minerals refers to the mineral formations of the earth's crust that can be effectively used in economic activity person. The distribution of minerals in the earth's crust is subject to geological laws. Lithosphere resources include fuel, ore and non-metallic minerals, as well as energy internal heat Earth. Thus, the lithosphere performs one of the most important functions for humanity - resource - supplying humans with almost all types of known resources.
In addition to the resource function, the lithosphere also performs another important function - geodynamic. Geological processes are continuously taking place on Earth. All geological processes are based on different sources energy. The source of internal processes is heat generated during radioactive decay and gravitational differentiation of substances inside the Earth.
Various tectonic movements of the earth's crust are associated with internal processes, creating the main forms of relief - mountains and plains, magmatism, earthquakes. Tectonic movements manifest themselves in slow vertical vibrations of the earth's crust, in the formation of rock folds and tectonic faults. The appearance of the earth's surface is constantly changing under the influence of lithospheric and intraterrestrial processes. We can see only a few of these processes with our own eyes. These, in particular, include such dangerous phenomena as earthquakes and volcanism caused by seismic activity of intraterrestrial processes.
The diversity of the chemical composition and physical and chemical properties of the earth’s crust lies next function lithosphere – geophysical and geochemical. Based on geological and geochemical data to a depth of 16 km, the average chemical composition rocks of the earth's crust: oxygen - 47%, silicon -27.5%, aluminum - 8.6%, iron - 5%, calcium, sodium, magnesium and potassium - 10.5%, all other elements account for about 1.5 %, including titanium - 0.6%, carbon - 0.1%, copper -0.01%, lead - 0.0016%, gold - 0.0000005%. It is obvious that the first eight elements make up almost 99% of the earth's crust. The fulfillment by the lithosphere of this function, no less important than the previous ones, leads to the most effective economic use almost all layers of the lithosphere. In particular, the most valuable in its composition and physicochemical properties is the top thin layer the earth's crust, which has natural fertility and is called soil.
Even in ancient times, people learned to use some of these resources for their needs, which was expressed in the names of historical periods of human development: “Stone Age”, “Bronze Age”, “Iron Age”. More than 200 different types are used today mineral resources. According to the figurative expression of Academician A.E. Fersman (1883-1945), now the entire periodic system of Mendeleev is laid at the feet of humanity.
Minerals are mineral formations of the earth's crust that can be effectively used in the economy; accumulations of minerals form deposits, and in large areas of distribution - pools.
The distribution of minerals in the earth's crust is subject to geological (tectonic) laws (Table 7.4).
Fuel minerals are of sedimentary origin and usually accompany the cover of ancient platforms and their internal and marginal troughs. So the name “pool” reflects their origin quite accurately - “sea pool”.
More than 3.6 thousand are known on the globe. coal basins and deposits, which together occupy 15% of the earth's land area. The bulk of coal resources are in Asia, North America and Europe and are concentrated in the ten largest basins of China, the USA, Russia, India, and Germany.
Oil and gas bearing More than 600 basins have been explored, 450 are being developed. Total number oil fields reach 35 thousand. The main reserves are located in the Northern Hemisphere and are deposits of the Mesozoic. Main part These reserves are also concentrated in a small number of the largest basins of Saudi Arabia, the USA, Russia, and Iran.
Ore minerals are usually confined to the foundations (shields) of ancient platforms, as well as to folded areas. In such areas they often form huge ore (metallogenic) belts, associated by their origin with deep faults in the earth's crust. Geothermal energy resources are especially large in countries and areas with increased seismic and volcanic activity (Iceland, Italy, New Zealand, the Philippines, Mexico, Kamchatka and North Caucasus in Russia, California in the USA).
For economic development, the most advantageous are territorial combinations (clusters) of mineral resources, which facilitate the complex processing of raw materials.
Extraction of mineral resources closed(mine) method is carried out on a global scale in foreign Europe, the European part of Russia, and the USA, where many deposits and basins located in the upper layers of the earth’s crust have already been heavily developed.
If minerals lie at a depth of 20-30 m, it is more profitable to remove them with a bulldozer top layer rock and mine open way. Open way For example, iron ore is mined in the Kursk region and coal in some deposits of Siberia.
In terms of reserves and production of many mineral resources, Russia ranks among the first in the world (gas, coal, oil, iron ore, diamonds).
In table Figure 7.4 shows the relationship between the structure of the earth’s crust, relief and distribution of minerals.
Table 7.4
Mineral deposits depending on the structure and return of a section of the earth's crust and landforms
| Landforms | Structure and age of a section of the earth's crust | Characteristic minerals | Examples |
| Plains | Shields of Archean-Proterozoic platforms | Abundant iron ore deposits | Ukrainian shield, Baltic shield of the Russian platform |
| Plates of ancient platforms, the cover of which was formed in Paleozoic and Mesozoic times | Oil, gas, coal, building materials | West Siberian Lowland, Russian Plain | |
| Mountains | Young fold mountains of alpine age | Polymetallic ores, building materials | Caucasus, Alps |
| Destroyed fold-block mountains of the Mesozoic, Hercynian and Caledonian folds | The richest structures in minerals: ores of ferrous (iron, manganese) and non-ferrous (chrome, copper, nickel, uranium, mercury) metals, placers of gold, platinum, diamonds | Kazakh small hill | |
| Rejuvenated mountains of Mesozoic and Paleozoic folding | Ores of ferrous and non-ferrous metals, primary and placer deposits of gold, platinum and diamonds | Ural, Appalachians, mountains of Central Europe | |
| Continental shoal (shelf) | Edge deflections | Oil, gas | Gulf of Mexico |
| Flooded part of slabs, platforms | Oil, gas | Persian Gulf | |
| Ocean bottom | Abyssal plains | Iron-manganese nodules | Bottom of the North Sea |
Hydrosphere
Hydrosphere(from Greek hydro- water and sphaira- ball) - the water shell of the Earth, which is a collection of oceans, seas and continental water basins - rivers, lakes, swamps, etc., groundwater, glaciers and snow covers.
It is believed that the water shell of the Earth formed in the early Archean, that is, approximately 3800 million years ago. During this period in the history of the Earth, a temperature was established on our planet at which water could be largely in a liquid state of aggregation.
Water as a substance has unique properties, which include the following:
♦ ability to dissolve many substances;
♦ high heat capacity;
♦ being in a liquid state in the temperature range from 0 to 100 °C;
♦ greater lightness of water in the solid state (ice) than in the liquid state.
Unique properties water allowed it to play an important role in the evolutionary processes occurring in the surface layers of the earth’s crust, in the cycle of matter in nature and to be a condition for the emergence and development of life on Earth. Water begins to fulfill its geological and biological functions in the history of the Earth after the emergence of the hydrosphere.
The hydrosphere consists of surface water and groundwater. Surface water hydrospheres cover 70.8% of the earth's surface. Their total volume reaches 1370.3 million km 3, which is 1/800 of the total volume of the planet, and the mass is estimated at 1.4 x 1018 tons. Surface waters, that is, waters covering land, include the World Ocean and continental water basins and continental ice. World ocean includes all the seas and oceans of the Earth.
Seas and oceans cover 3/4 of the land surface, or 361.1 million km 2. The bulk of surface water is concentrated in the World Ocean - 98%. The world's oceans are conventionally divided into four oceans: the Atlantic, Pacific, Indian and Arctic. It is believed that the current sea level was established about 7,000 years ago. According to geological studies, ocean level fluctuations over the past 200 million years have not exceeded 100 m.
The water in the World Ocean is salty. The average salt content is about 3.5% by weight, or 35 g/l. Their qualitative composition is as follows: the cations are dominated by Na +, Mg 2+, K +, Ca 2+, the anions are Cl-, SO 4 2-, Br -, CO3 2-, F -. It is believed that the salt composition of the World Ocean has remained constant since the Paleozoic era, when life began to develop on land, that is, for approximately 400 million years.
Continental water basins They are rivers, lakes, swamps, and reservoirs. Their waters make up 0.35% of the total mass of surface waters of the hydrosphere. Some continental bodies of water - lakes - contain salt water. These lakes are either of volcanic origin, isolated remnants of ancient seas, or formed in an area of thick deposits of soluble salts. However, continental water bodies are mostly fresh.
Fresh water from open reservoirs also contains soluble salts, but in small quantities. Depending on the content of dissolved salts, fresh water is divided into soft and hard. The less salts dissolved in water, the softer it is. The hardest fresh water contains salts no more than 0.005% by weight, or 0.5 g/l.
Continental ice make up 1.65% of the total mass of surface waters of the hydrosphere; 99% of the ice is found in Antarctica and Greenland. Total weight Snow and ice on Earth is estimated at 0.0004% of the mass of our planet. This is enough to cover the entire surface of the planet with a layer of ice 53 m thick. According to calculations, if this mass melts, the ocean level will rise by 64 m.
The chemical composition of surface waters of the hydrosphere is approximately equal to the average composition sea water. The predominant chemical elements by weight are oxygen (85.8%) and hydrogen (10.7%). Surface waters contain significant amounts of chlorine (1.9%) and sodium (1.1%). There is a significantly higher content of sulfur and bromine than in the earth's crust.
Groundwater of the hydrosphere contain the main supply of fresh water: It is assumed that the total volume of groundwater is approximately 28.5 billion km 3. This is almost 15 times more than in the World Ocean. It is believed that groundwater is the main reservoir that replenishes all surface water bodies. The underground hydrosphere can be divided into five zones.
Cryozone. Ice area. The zone covers the polar regions. Its thickness is estimated to be within 1 km.
Liquid water zone. Covers almost the entire earth's crust.
Vapor water zone limited to a depth of 160 km. It is believed that the water in this zone has a temperature of 450 °C to 700 °C and is under pressure up to 5 GPa 1.
Below, at depths of up to 270 km, is located zone of monomeric water molecules. It covers layers of water with a temperature range from 700 °C to 1000 °C and pressure up to 10 GPa.
Dense water zone supposedly extends to depths of 3000 km and encircles the entire mantle of the Earth. The water temperature in this zone is estimated to range from 1000° to 4000 °C, and the pressure is up to 120 GPa. Water under such conditions is completely ionized.
The Earth's hydrosphere performs important functions: it regulates the temperature of the planet, ensures the circulation of substances, and is integral part biosphere.
Direct impact on temperature regulation The hydrosphere provides the surface layers of the Earth due to one of the important properties of water - high heat capacity. For this reason, surface waters accumulate solar energy, and then it is slowly released into the surrounding space. The equalization of temperature on the Earth's surface occurs solely due to the water cycle. In addition, snow and ice are very reflective
ability: it exceeds the average for the earth's surface by 30%, Therefore, at the poles, the difference between absorbed and emitted energy is always negative, that is, the energy absorbed by the surface is less than emitted. This is how the thermoregulation of the planet occurs.
Security circulation of substances- another important function of the hydrosphere.
The hydrosphere is in constant interaction with the atmosphere, the earth's crust and the biosphere. The water of the hydrosphere dissolves air in itself, concentrating oxygen, which is subsequently used by aquatic living organisms. Carbon dioxide in the air, which is formed mainly as a result of the respiration of living organisms, fuel combustion and volcanic eruptions, has high solubility in water and accumulates in the hydrosphere. The hydrosphere also dissolves heavy inert gases - xenon and krypton, the content of which in water is higher than in air.
The waters of the hydrosphere, evaporating, enter the atmosphere and fall in the form of precipitation, which penetrates rocks, destroying them. This is how water participates in processes weathering rocks. Rock fragments are carried by flowing waters into rivers, and then into seas and oceans or into closed continental reservoirs and are gradually deposited at the bottom. These deposits later turn into sedimentary rocks.
It is believed that the main cations of sea water - cations of sodium, magnesium, potassium, calcium - were formed as a result of weathering of rocks and the subsequent removal of weathering products by rivers into the sea. The most important anions of seawater - the anions of chlorine, bromine, fluorine, sulfate ion and carbonate ion - probably originate from the atmosphere and are associated with volcanic activity.
Some of the soluble salts are systematically removed from the hydrosphere through their precipitation. For example, when carbonate ions dissolved in water interact with calcium and magnesium cations, insoluble salts are formed, which sink to the bottom in the form of carbonate sedimentary rocks. In the precipitation of certain salts big role played by organisms inhabiting the hydrosphere. They extract individual cations and anions from seawater, concentrating them in their skeletons and shells in the form of carbonates, silicates, phosphates and other compounds. After the death of organisms, their hard shells accumulate on the seabed and form thick layers of limestone, phosphorites and various siliceous rocks. The overwhelming majority of sedimentary rocks and such valuable minerals as oil, coal, bauxite, various salts, etc., were formed in past geological periods in various reservoirs of the hydrosphere. It has been established that even the most ancient rocks, the absolute age of which reaches about 1.8 billion years, represent highly altered sediments formed in an aquatic environment. Water is also used in the process of photosynthesis, which produces organic matter and oxygen.
Life on Earth began in the hydrosphere approximately 3500 million years ago. The evolution of organisms continued exclusively in the aquatic environment until the beginning of the Paleozoic era, when approximately 400 million years ago the gradual migration of animal and plant organisms to land began. In this regard, the hydrosphere is considered a component of the biosphere (biosphere - sphere of life, area of habitat of living organisms).
Living organisms are distributed extremely unevenly in the hydrosphere. The number and diversity of living organisms in separate areas surface water is determined by many reasons, including a complex of factors external environment: temperature, water salinity, light, pressure. With increasing depth, the limiting effect of illumination and pressure increases: the amount of incoming light decreases sharply, and the pressure, on the contrary, becomes very high. Thus, the seas and oceans are inhabited mainly by littoral zones, that is, zones no deeper than 200 m, most warmed by the sun's rays.
Characterizing the functions of the hydrosphere on our planet, V.I. Vernadsky noted: “Water determines and creates the entire biosphere. It creates the main features of the earth’s crust, right down to the magma shell.”
Atmosphere
Atmosphere(from Greek atmos- steam, evaporation and sphaira- ball) - the shell of the Earth consisting of air.
Included air includes a number of gases and particles of solid and liquid impurities suspended in them - aerosols. The mass of the atmosphere is estimated at 5.157 x 10 15 tons. The air column exerts pressure on the Earth's surface: the average atmospheric pressure at sea level is 1013.25 hPa, or 760 mm Hg. Art. The pressure is 760 mmHg. Art. equated to an off-system unit of pressure - 1 atmosphere (1 atm.). The average air temperature at the Earth's surface is 15 °C, with temperatures varying from approximately 57 °C in subtropical deserts to 89 °C in Antarctica.
The atmosphere is heterogeneous. The following layers of the atmosphere are distinguished: troposphere, stratosphere, mesosphere, thermosphere And exosphere, which differ in the characteristics of temperature distribution, air density and some other parameters. The parts of the atmosphere occupying an intermediate position between these layers are called tropopause, stratopause And mesopause.
Troposphere - the lower layer of the atmosphere with a height of 8-10 km in polar latitudes and up to 16-18 km in the tropics. The troposphere is characterized by a drop in air temperature with height - with every kilometer removed from the Earth's surface, the temperature decreases by approximately 6°C. Air density decreases rapidly. About 80% of the total mass of the atmosphere is concentrated in the troposphere.
Stratosphere located at altitudes on average from 10-15 km to 50-55 km from the Earth's surface. The stratosphere is characterized by an increase in temperature with height. The increase in temperature occurs due to the absorption of short-wave radiation from the Sun, primarily UV (ultraviolet) rays, by the ozone located in this layer of the atmosphere. At the same time, in the lower part of the stratosphere to a level of about 20 km, the temperature changes little with altitude and may even decrease slightly. Higher up, the temperature begins to increase - slowly at first, but from a level of 34-36 km much faster. In the upper part of the stratosphere at an altitude of 50-55 km, the temperature reaches 260-270 K.
Mesosphere- a layer of the atmosphere located at altitudes of 55-85 km. In the mesosphere, the air temperature decreases with increasing altitude - from approximately 270 K at the lower boundary to 200 K at the upper boundary.
Thermosphere extends at altitudes from approximately 85 km to 250 km from the Earth's surface and is characterized by a rapid increase in air temperature, reaching 800-1200 K at an altitude of 250 km. The increase in temperature occurs due to the absorption of corpuscular and X-ray radiation from the Sun by this layer of the atmosphere; This is where meteors slow down and burn up. Thus, the thermosphere serves as the Earth's protective layer.
Above the troposphere is exosphere, the upper limit of which is arbitrary and is marked at an altitude of approximately 1000 km above the Earth’s surface. From the exosphere atmospheric gases dissipate into outer space. This is how a gradual transition from the atmosphere to interplanetary space occurs.
Atmospheric air near the Earth's surface it consists of various gases, mainly nitrogen (78.1% by volume) and oxygen (20.9% by volume). Air also contains the following gases in small quantities: argon, carbon dioxide, helium, ozone, radon, water vapor. In addition, air may contain various variable components: nitrogen oxides, ammonia, etc.
In addition to gases, air contains atmospheric aerosol, which is very small solid and liquid particles suspended in the air. Aerosol is formed during the life of organisms, human economic activity, volcanic eruptions, the rise of dust from the surface of the planet and from cosmic dust falling into the upper layers of the atmosphere.
The composition of atmospheric air up to a height of about 100 km is generally constant in time and homogeneous in different areas Earth. At the same time, the content of variable gaseous components and aerosols is not the same. Above 100-110 km, partial decomposition of oxygen, carbon dioxide and water molecules occurs. At an altitude of about 1000 km, light gases - helium and hydrogen - begin to predominate, and even higher the Earth's atmosphere gradually turns into interplanetary gas.
water vapor- important component air. It enters the atmosphere through evaporation from the surface, water and moist soil, as well as through transpiration by plants. The relative content of water vapor in the air varies at the earth's surface from 2.6% in the tropics to 0.2% in polar latitudes. With distance from the Earth's surface, the amount of water vapor in the atmospheric air quickly falls, and already at an altitude of 1.5-2 km it decreases by half. In the troposphere, due to a decrease in temperature, water vapor condenses. When water vapor condenses, clouds form, from which precipitation falls in the form of rain, snow, and hail. The amount of precipitation that fell on the Earth is equal to the amount that evaporated from the surface. Lands of water. Excess water vapor over the oceans is transported to the continents by air currents. The amount of water vapor transported in the atmosphere from the ocean to the continents is equal to the volume of river runoff flowing into the oceans.
Ozone concentrated 90% in the stratosphere, the rest of it is in the troposphere. Ozone absorbs UV radiation from the Sun, which negatively affects living organisms. Areas with low levels of ozone in the atmosphere are called ozone holes.
The greatest variations in the thickness of the ozone layer are observed at high latitudes, so the likelihood of ozone holes occurring in areas close to the poles is higher than near the equator.
Carbon dioxide enters the atmosphere in significant quantities. It is constantly released as a result of the respiration of organisms, combustion, volcanic eruptions and other processes occurring on Earth. However, the content of carbon dioxide in the air is low, since most of it is dissolved in the waters of the hydrosphere. However, it is noted that over the past 200 years, the content of carbon dioxide in the atmosphere has increased by 35%. The reason for such a significant increase is active human economic activity.
The main source of heat for the atmosphere is the Earth's surface. Atmospheric air transmits the sun's rays to the earth's surface quite well. Solar radiation reaching the Earth is partially absorbed by the atmosphere - mainly by water vapor and ozone, but the overwhelming majority reaches the earth's surface.
The total solar radiation reaching the Earth's surface is partially reflected from it. The magnitude of reflection depends on the reflectivity of a particular area of the earth's surface, the so-called albedo. The average albedo of the Earth is about 30%, while the difference between the albedo value is from 7-9% for black soil to 90% for freshly fallen snow. When heated, the earth's surface releases heat rays into the atmosphere and heats its lower layers. In addition to the main source of thermal energy of the atmosphere - the heat of the earth's surface; heat enters the atmosphere as a result of condensation of water vapor, as well as by absorption of direct solar radiation.
Uneven heating of the atmosphere in different regions of the Earth causes unequal pressure distribution, which leads to the movement of air masses along the Earth's surface. Air masses move from areas with high pressure in an area of low pressure. This movement of air masses is called by the wind. Under certain conditions, wind speed can be very high, up to 30 m/s or more (more than 30 m/s is already hurricane).
The state of the lower layer of the atmosphere in a given place and at a given time is called weather. Weather is characterized by air temperature, precipitation, wind strength and direction, cloudiness, air humidity and atmospheric pressure. Weather is determined by atmospheric circulation conditions and geographical location terrain. It is most stable in the tropics and most variable in the middle and high latitudes. The nature of the weather and its seasonal dynamics depend on climate in this territory.
Under, climate the most frequently repeated weather features for a given area that persist over a long period of time are understood. These are characteristics averaged over 100 years - temperature, pressure, precipitation, etc. The concept of climate (from Greek, klima- tilt) arose back in Ancient Greece. Even then it was understood that weather conditions depended on the angle at which the sun's rays hit the Earth's surface. The leading condition for establishing a certain climate in a given territory is the amount of energy per unit area. It depends on the total solar radiation falling on the earth's surface and on the albedo of this surface. Thus, in the region of the equator and at the poles, the temperature changes little throughout the year, and in subtropical regions and mid-latitudes the annual temperature range can reach 65 °C. The main climate-forming processes are heat exchange, moisture exchange and atmospheric circulation. All these processes have one source of energy - the Sun.
The atmosphere is an essential condition for all forms of life. Highest value The following gases included in the air are essential for the life of organisms: oxygen, nitrogen, water vapor, carbon dioxide, ozone. Oxygen is necessary for respiration for the vast majority of living organisms. Nitrogen, absorbed from the air by some microorganisms, is necessary for the mineral nutrition of plants. Water vapor, condensing and falling out as precipitation, is the source of water on land. Carbon dioxide is the starting material for the process of photosynthesis. Ozone absorbs hard UV radiation harmful to organisms.
It is believed that the modern atmosphere is of secondary origin: it was formed after the completion of the formation of the planet about 4.5 billion years ago from gases released by the solid shells of the Earth. During the geological history of the Earth, the atmosphere, under the influence of various factors, has undergone significant changes in its composition.
The development of the atmosphere depends on the geological and geochemical processes occurring on Earth. After the emergence of life on our planet, that is, approximately 3.5 billion years ago, living organisms began to have a significant influence on the development of the atmosphere. A significant part of the gases - nitrogen, carbon dioxide, water vapor - arose as a result of volcanic eruptions. Oxygen appeared about 2 billion years ago as a result of the activity of photosynthetic organisms, which originally arose in surface waters ocean.
Recently, there have been noticeable changes in the atmosphere associated with active human economic activity. Thus, according to observations, over the past 200 years there has been a significant increase in the concentration of greenhouse gases: the content of carbon dioxide has increased by 1.35 times, methane - by 2.5 times. The content of many other variable components in the air has increased significantly.
The ongoing changes in the state of the atmosphere - increased concentrations of greenhouse gases, ozone holes, air pollution - represent global environmental problems modernity.
65. ECOLOGICAL FUNCTIONS OF THE LITHOSPHERE: RESOURCE, GEODYNAMIC, GEOPHYSICAL-GEOCHEMICAL
Even in ancient times, people learned to use for their needs some of the resources of the lithosphere and other shells of the Earth, which was reflected in the names of the historical periods of human development: “Stone Age”, “Bronze Age”, “Iron Age”. There are more than 200 different types of resources in use these days. All natural resources should be clearly distinguished from natural conditions.
Natural resources- these are the bodies and forces of nature, which at a given level of development of productive forces and knowledge can be used to meet the needs of human society in the form of direct participation in material activity.
Under minerals refers to the mineral formations of the earth's crust that can be effectively used in human economic activity. The distribution of minerals in the earth's crust is subject to geological laws. The resources of the lithosphere include fuel, ore and non-metallic minerals, as well as the energy of the Earth's internal heat. Thus, the lithosphere performs one of the most important functions for humanity - resource - supplying humans with almost all types of known resources.
In addition to the resource function, the lithosphere also performs another important function - geodynamic. Geological processes are continuously taking place on Earth. All geological processes are based on different energy sources. The source of internal processes is heat generated during radioactive decay and gravitational differentiation of substances inside the Earth.
Various tectonic movements of the earth's crust are associated with internal processes, creating the main forms of relief - mountains and plains, magmatism, earthquakes. Tectonic movements manifest themselves in slow vertical vibrations of the earth's crust, in the formation of rock folds and tectonic faults. The appearance of the earth's surface is constantly changing under the influence of lithospheric and intraterrestrial processes. We can see only a few of these processes with our own eyes. These, in particular, include such dangerous phenomena as earthquakes and volcanism caused by seismic activity of intraterrestrial processes.
The diversity of the chemical composition and physical and chemical properties of the earth’s crust is the next function of the lithosphere – geophysical and geochemical. Based on geological and geochemical data to a depth of 16 km, the average chemical composition of the earth's crust rocks was calculated: oxygen - 47%, silicon -27.5%, aluminum - 8.6%, iron - 5%, calcium, sodium, magnesium and potassium - 10 .5%, all other elements account for about 1.5%, including titanium - 0.6%, carbon - 0.1%, copper -0.01%, lead - 0.0016%, gold - 0 .0000005%. It is obvious that the first eight elements make up almost 99% of the earth's crust. The fulfillment by the lithosphere of this function, no less important than the previous ones, leads to the most effective economic use of almost all layers of the lithosphere. In particular, the most valuable in its composition and physical and chemical properties is the upper thin layer of the earth’s crust, which has natural fertility and is called soil.
