Minerals of sedimentary rocks. Types of minerals

On the surface of the Earth, as a result of the action of various exogenous factors, sediments are formed, which are further compacted, undergo various physicochemical changes - diagenesis, and turn into sedimentary rocks. Sedimentary rocks cover about 75% of the surface of the continents with a thin cover. Many of them are minerals, others contain them.

There are three groups of sedimentary rocks:

Clastic rocks resulting from the mechanical destruction of any rocks and the accumulation of the resulting debris;

clayey rocks, which are the product of predominantly chemical destruction of rocks and the accumulation of clay minerals that have arisen in this case;

chemical (chemogenic) and organogenic rocks formed as a result of chemical and biological processes.

When describing sedimentary rocks, as well as igneous rocks, one should pay attention to their mineral composition and structure. The first is a defining feature for chemical and organogenic rocks, as well as clayey ones in their microscopic study. Clastic rocks may contain fragments of any minerals and rocks.

The most important feature characterizing the structure of sedimentary rocks is their layered texture. The formation of layering is associated with the conditions of sediment accumulation. Any change in these conditions causes either a change in the composition of the deposited material or a stop in its supply. In the section, this leads to the appearance of layers separated by bedding surfaces and often differing in composition and structure. The layers are more or less flat bodies, the horizontal dimensions of which are many times greater than their thickness (thickness). The thickness of the layers can reach tens of meters or not exceed fractions of a centimeter. The study of layering provides a great deal of material for understanding the paleogeographic conditions under which the studied sedimentary sequence was formed. For example, in seas at a distance from the coast, under conditions of a relatively calm regime of water movement, parallel, primarily horizontal layering is formed, in coastal-marine conditions - diagonal, in sea and river flows - oblique, etc. An important textural feature of sedimentary rocks is also porosity, which characterizes the degree of their permeability for water, oil, gases, as well as stability under loads. Only relatively large pores are visible to the naked eye; smaller ones are easy to detect by checking the intensity of water absorption by the rock. For example, rocks that have a thin, invisible porosity stick to the tongue.

The structure of sedimentary rocks reflects their origin - clastic rocks consist of fragments of older rocks and minerals, i.e. have a clastic structure; clayey are composed of the smallest grains of predominantly clay minerals invisible to the naked eye - a pelitic structure; chemobiogenic have either a crystalline structure (from clearly visible to cryptocrystalline), or amorphous, or organogenic, isolated in cases where the rock is an accumulation of skeletal parts of organisms or their fragments.

Most sedimentary rocks are the product of weathering and erosion of material from pre-existing rocks. A minor part of precipitation comes from organic material, volcanic ash, meteorites, mineralized waters. There are sediments of terrigenous (Table 1.), sediments of organic, volcanic, magmatic and extraterrestrial origin.

Table 1. Material composing sedimentary rocks

Minerals extracted from sedimentary rocks

Sedimentary rocks are of exceptional practical and theoretical importance. In this respect, no other rocks can compare with them.

Sedimentary rocks are the most important in practical terms: these are minerals, foundations for structures, and soils.

Mankind extracts more than 90% of minerals from sedimentary rocks. Most of them are taken only from sedimentary rocks: oil, gas, coal and other fossil fuels, aluminum, manganese and other ores, cement raw materials, salts, fluxes for metallurgy, sands, clays, fertilizers, etc.

Ores of ferrous and non-ferrous metals. The main metal of modern technology - iron is mined almost entirely (more than 90%) from sedilites, if we take into account the Precambrian ferruginous quartzites, which are currently metamorphic rocks, but retain their original sedimentary material composition. The main ores still remain young Meso-Cenozoic oolitic marine and continental deposits of alluvial, deltaic and coastal-marine types and weathering crust of tropical countries: Cuba, South America, Guinea and other countries of Equatorial Africa, the islands of Indian and Pacific Oceans, Australia. These ores are usually pure, readily available for open pit mining, often ready for the smelting process, and their reserves are colossal. They begin to compete with ferruginous quartzites, or jaspilites, of the Archean and Proterozoic, gigantic, the reserves of which are available on all continents, but they require enrichment. They are also developed in an open way, for example, in the Mikhailovsky and Lebedinsky quarries of the KMA, in Ukraine, in South Australia and other countries. In addition to these two main types, siderite ores of the Proterozoic (Riphean) Bakala (Bashkiria) are important. Other types are lacustrine-swampy (the iron ore plants of Petrozavodsk worked on them under Peter 1), volcanogenic-sedimentary (limonite cascades, etc.), siderite concretions of paralytic coal-bearing strata are secondary.

Manganese ores are 100% mined from sedimentary rocks. The main types of their deposits are shallow marine, confined to sponolites, sands, and clays. These are the giant deposits of Nikopol (Ukraine), Chiatura (Western Georgia), the eastern slope of the Urals (Polunochnoe, Marsyaty, etc.), as well as Laba (Northern Caucasus) and Mangyshlak. The most striking thing is that almost all of them are confined to a narrow time interval - the Oligocene. The second type is volcanic-sedimentary ores of the Paleozoic, mainly Devonian: in the Urals in the Magnitogorsk eugeosynclinal trough, often in jaspers; in Kazakhstan - in the depressions of the Atasu region, etc. Iron-manganese nodules of the oceans - minor ores for manganese. This metal can only be mined along with cobalt, nickel, copper.

Chrome ores, on the contrary, are mined mainly from igneous rocks, and sedimentary rocks account for only 7%. All other components of ferrous metallurgy - fluxes - lowering the melting point (limestones), coke (coking coals), molding sands - are extracted entirely from sedimentary rocks.

Ores of non-ferrous and light metals are 100-50% mined from sedimentary rocks. Aluminum is completely smelted from bauxites, as is magnesium ores from magnesites of sedimentary genesis. The main type of bauxite deposits are modern or Meso-Cenozoic lateritic weathering crusts that develop in the tropical humid belt of the Earth. Other types are redeposited lateritic weathering crusts of near (colluvium, alluvium, karst strips) or somewhat more distant (coastal lagoon and other calm zone) weathering. The largest such deposits are the Lower Carboniferous Tikhvin, Middle Devonian Krasnaya Shapochka, Cheremukhovskoye and other deposits that make up the North Ural bauxite region (SUBR), North American (Apkansas and others), Hungarian and others.

Magnesium is extracted mainly from magnesites and partly from dolomites of sedimentary genesis. The largest in Russia and the world are the Riphean Satka deposits in Bashkiria of a metasomatic, obviously catagenetic, genesis after primary dolomites. The thickness of the magnesite bodies reaches many tens of meters, and the thickness of the thickness is 400 m.

Titanium ores are 80% sedimentary, placer (rutile, ilmenite, titanomagnetites, etc.), consisting of residual minerals mobilized from igneous rocks.

Copper ores are 72% sedimentary - cuprous sandstones, clays, shales, limestones, volcanic-sedimentary rocks. For the most part, they are associated with red-colored arid formations of the Devonian, Permian, and other ages. Nickel ores are 76% sedimentary, mainly weathering crusts of ultrabasic rocks, lead-zinc ore is 50% volcanic-sedimentary, hydrothermal-sedimentary, and tin - cassiterite placers - 50% sedimentary.

Ores of "small" and rare elements are l00-75% sedimentary: 100% zircon-hafnium (placers of zircons, rutiles, etc.), 80% cobalt, 80% rare earth (monazite and other placers) and 75 % tantalum-niobium, also largely placer.

Sedimentary minerals most characteristic of platforms, as there is a platform cover. Mostly these are non-metallic minerals and combustibles, the leading role among which is played by gas, oil, coal, oil shale. They were formed from the remains of plants and animals accumulated in the coastal parts of the shallow seas and in the lacustrine-marsh conditions of the dry land. These plentiful organic remains could accumulate only in sufficiently moist and warm conditions favorable for luxuriant development. In hot dry conditions in shallow seas and coastal lagoons, salts accumulated, which were used as raw materials in.

Mining

There are several ways mining. Firstly, it is an open method in which rocks are mined in quarries. It is economically more profitable, as it contributes to obtaining a cheaper product. However, an abandoned quarry can lead to the formation of a wide network. The mine method of coal mining is expensive, therefore it is more expensive. The cheapest way to extract oil is by flowing, when oil rises through the well under oil gases. The pumping method of extraction is also common. There are also special ways of extracting minerals. They are called geotechnical. With their help, ore is mined from the bowels of the Earth. This is done by pumping hot water, solutions into the formations containing the necessary mineral. Other wells pump out the resulting solution and separate the valuable component.

The need for minerals is constantly growing, the extraction of mineral raw materials is increasing, but minerals are exhaustible Natural resources Therefore, it is necessary to use them more economically and fully.

There are several ways to do this:

• reduction of losses of minerals during their extraction;
• more complete extraction of all useful components from the rock;
• integrated use of minerals;
• search for new, more promising deposits.

Thus, the main direction of the use of minerals in the coming years should not be an increase in the volume of their extraction, but a more rational use.

In modern exploration of minerals, it is necessary to use not only the latest technology and sensitive instruments, but also a scientific forecast for the search for deposits, which helps to purposefully, on a scientific basis, conduct exploration of the subsoil. Thanks to such methods, diamond deposits in Yakutia were first scientifically predicted and then discovered. A scientific forecast is based on knowledge of the connections and conditions for the formation of minerals.

Brief description of the main minerals

The hardest of all minerals. Its composition is pure carbon. Occurs in placers and as inclusions in rocks. Diamonds are colorless, but there are also dyed in different colors. A cut diamond is called a diamond. Its weight is usually measured in carats (1 carat = 0.2 g). The largest diamond was found in the South: it weighed over 3,000 carats. Most diamonds are mined in Africa (98% of the production in the capitalist world). In Russia large deposits diamonds are located in Yakutia. Clear crystals are used to make precious stones. Until 1430, diamonds were considered common gemstones. The trendsetter for them was the Frenchwoman Agnes Sorel. Opaque diamonds, due to their hardness, are used in industry for cutting and engraving, as well as for grinding glass and stone.

Soft malleable metal yellow color, heavy, does not oxidize in air. In nature, it is found mainly in its pure form (nuggets). The largest nugget, weighing 69.7 kg, was found in Australia.

Gold is also found in the form of a placer - this is the result of weathering and erosion of the deposit, when grains of gold are released and carried away to form placers. Gold is used in the manufacture of precision instruments and various ornaments. In Russia, gold lies on and in. Abroad - in Canada, South Africa,. Since gold is found in nature in small quantities and its extraction is associated with high costs, it is considered a precious metal.

Platinum(from Spanish plata - silver) - a precious metal from white to gray-steel color. Differs in infusibility, resistance to chemical influences and electrical conductivity. It is mined mainly in placers. It is used for the manufacture of chemical glassware, in electrical engineering, jewelry and dentistry. In Russia, platinum is mined in the Urals and Eastern Siberia. Abroad - in South Africa.

Gems(gems) - mineral bodies that have the beauty of color, brilliance, hardness, transparency. They are divided into two groups: stones for cutting and ornamental. The first group includes diamond, ruby, sapphire, emerald, amethyst, aquamarine. To the second group - malachite, jasper, rock crystal. All gemstones, as a rule, are of igneous origin. However, pearls, amber, coral are minerals of organic origin. Precious stones are used in jewelry and for technical purposes.

tuffs- rocks of various origins. Calcareous tuff is a porous rock formed as a result of precipitation of calcium carbonate from springs. This tuff is used to produce cement and lime. Volcanic tuff - cemented. Tuffs are used as a building material. Has different colors.

micas- rocks that have the ability to split into the thinnest layers with a smooth surface; found as impurities in sedimentary rocks. Various micas are used as a good electrical insulator, for the manufacture of windows in metallurgical furnaces, in the electrical and radio industries. In Russia, micas are mined in Eastern Siberia, c. Industrial development of mica deposits is carried out in Ukraine, in the USA, .

Marble- a crystalline rock formed as a result of limestone metamorphism. He happens various colors. Marble is used as a building material for wall cladding, in architecture and sculpture. In Russia, there are many of its deposits in the Urals and the Caucasus. Abroad, marble quarried in is the most famous.

Asbestos(Greek inextinguishable) - a group of fibrous fireproof rocks that split into soft fibers of a greenish-yellow or almost white color. It lies in the form of veins (a vein is a mineral body that fills a crack in the earth's crust, usually has a plate-like shape, going vertically to great depths. The length of the veins reaches two or more kilometers), among igneous and sedimentary rocks. It is used for the manufacture of special fabrics (fire insulation), tarpaulins, fire-resistant roofing materials, as well as thermal insulation materials. In Russia, asbestos is mined in the Urals, in, abroad - in other countries.

Asphalt(resin) - a fragile resinous rock of brown or black color, which is a mixture of hydrocarbons. Asphalt melts easily, burns with a smoky flame, is a product of the transformation of certain types of oil, from which some of the substances have evaporated. Asphalt often penetrates sandstones, limestones, marl. It is used as a building material for road surfacing, in the electrical engineering and rubber industry, for the preparation of varnishes and mixtures for waterproofing. The main asphalt deposits in Russia are the Ukhta region, abroad - in, in France,.

Apatity- minerals rich in phosphoric salts, green, gray and other colors; found among various igneous rocks, sometimes forming large accumulations. Apatites are mainly used for the production of phosphate fertilizers, they are also used in the ceramics industry. In Russia, the largest deposits of apatite are located in, on. Abroad they are mined in the Republic of South Africa.

Phosphorites- sedimentary rocks rich in phosphorus compounds, which form grains in the rock or hold together various minerals into a dense rock. Phosphorites are dark grey. They are used, like apatites, to obtain phosphate fertilizers. In Russia, phosphorite deposits are common in Moscow and Kirov regions. Abroad, they are mined in the USA (Peninsula Florida) and.

aluminum ores- minerals and rocks used to produce aluminium. The main aluminum ores are bauxites, nephelines and alunites.

bauxites(the name came from the Bo area in southern France) - sedimentary rocks of red or brown color. 1/3 of their world reserves lie in the north, and the country is one of the leading states in their production. In Russia, bauxites are mined in. The main component of bauxite is aluminum oxide.

Alunites(the name comes from the word alun - alum (fr.) - minerals, which include aluminum, potassium and other inclusions. Alunite ore can be a raw material for obtaining not only aluminum, but also potash fertilizers and sulfuric acid. There are deposits of alunites in the USA , China, Ukraine, and other countries.

Nephelines(the name comes from the Greek "nephele", which means cloud) - minerals of complex composition, gray or green, containing a significant amount of aluminum. They are part of the igneous rocks. In Russia, nephelines are mined in and in Eastern Siberia. The aluminum obtained from these ores is a soft metal, gives strong alloys, is widely used, as well as in the manufacture of household goods.

Iron ores- natural mineral accumulations containing iron. They are diverse in terms of mineralogical composition, the amount of iron in them, and various impurities. Impurities can be valuable ( manganese chromium, cobalt, nickel) and harmful (sulfur, phosphorus, arsenic). The main ones are brown iron ore, red iron ore, magnetic iron ore.

brown iron ore, or limonite, is a mixture of several minerals containing iron with an admixture of clay substances. It has a brown, yellow-brown or black color. It occurs most often in sedimentary rocks. If the ores of brown iron ore - one of the most common iron ores - have an iron content of at least 30%, then they are considered industrial. The main deposits are in Russia (Ural, Lipetsk), in Ukraine (), France (Lorraine), on.

Hematite, or hematite, is a red-brown to black mineral containing up to 65% iron.

It occurs in various rocks in the form of crystals and thin plates. Sometimes it forms clusters in the form of hard or earthy masses of bright red color. The main deposits of red iron ore are in Russia (KMA), Ukraine (Krivoy Rog), USA, Brazil, Kazakhstan, Canada, Sweden.

Magnetic iron ore, or magnetite, is a black mineral containing 50-60% iron. It is high quality iron ore. Composed of iron and oxygen, highly magnetic. It occurs in the form of crystals, inclusions and solid masses. The main deposits are in Russia (Urals, KMA, Siberia), Ukraine (Krivoy Rog), Sweden and the USA.

manganese ores- mineral compounds containing manganese, the main property of which is to impart malleability and hardness to steel and cast iron. Modern metallurgy is unthinkable without manganese: a special alloy is smelted - ferromanganese, containing up to 80% manganese, which is used to smelt high-quality steel. In addition, manganese is necessary for the growth and development of animals, it is a microfertilizer. The main ore deposits are located in Ukraine (Nikolskoye), India, Brazil and the Republic of South Africa.

Tin ores- Numerous minerals containing tin. Tin ores with a tin content of 1-2% or more are being developed. These ores require enrichment - an increase in the valuable component and the separation of waste rock, therefore, ores with a tin content increased to 55% are used for smelting. Tin does not oxidize, which has led to its widespread use in the canning industry. In Russia, tin ores occur in Eastern Siberia and on, and abroad they are mined in Indonesia, on the peninsula.

Nickel ores- mineral compounds containing nickel. It does not oxidize in air. The addition of nickel to steels greatly increases their elasticity. Pure nickel is used in mechanical engineering. In Russia, it is mined on the Kola Peninsula, in the Urals, in Eastern Siberia; abroad - in Canada, on, in Brazil.

Uranium-radium ores- mineral accumulations containing uranium. Radium is a product of the radioactive decay of uranium. The content of radium in uranium ores is negligible - up to 300 mg per 1 ton of ore. are of great importance, since the fission of the nuclei of each gram of uranium can give 2 million times more energy than burning 1 gram of fuel, so they are used as fuel in nuclear power plants to generate cheap electricity. Uranium-radium ores are mined in Russia, the USA, China, Canada, Congo, and other countries of the world.

Most of all chemical elements, including very valuable ones, are dispersed in rocks. Only a very small part of them is concentrated in mineral deposits. But although the content of elements in rocks is low, their total amount in the bowels of the earth is grandiose.

All minerals according to the conditions of their formation are divided into deep and surface. Deep deposits are called endogenous(from the Greek words "edo" - inside, "geos" - origin), and superficial - exogenous(Greek "echo" - outside).

Deep, or endogenous, deposits are formed as a result of the introduction into the earth's crust of hot underground melts, or magmas, and their solidification. Magma penetrates through cracks into rocks. At the same time, only an insignificant part of the magma in volcanoes reaches the Earth's surface, forming lava flows and accumulations of volcanic ash. Most of the magma does not reach the earth's surface and solidifies at depth, forming deep crystalline igneous rocks, such as granite. Igneous rocks frozen at depth and on the surface of the Earth are widely used as natural stone building materials.

Due to the difference in the physical and chemical properties of the elements, in the process of cooling magmatic melts in the bowels of the Earth, they are separated and accumulations of some chemical elements are formed.

When the so-called basic magmas, containing no more than 50% silicon oxide in their composition, cool down, the process of separation of substances in them proceeds similarly to iron smelting in blast furnaces. At the same time, in accumulations of magma solidifying at depth, light rocks float up, and heavy minerals sink to the bottom of the magma reservoir. These heavy minerals form ore igneous deposits. The most significant of them are deposits iron and titanium, chromium and platinum, copper and nickel. Close to them in their origin and deposits diamonds in kimberlite pipes Siberia and South Africa, but for their formation, in addition to high temperature, enormous pressure is needed.

Valuable minerals separate completely differently when so-called acid magmas containing more than 50% silicon oxide solidify. These magmas contain an increased content of various gases, including water vapor. Gases dissolve many chemical compounds, especially metallic ones, and prevent them from precipitating on early stages cooling of magma. Therefore, conditions for their concentration are created in the latest remains of magmatic melts that have not had time to completely solidify. Part of these residual magma melts, saturated with hot gases and valuable elements dissolved in them, penetrates through cracks into rocks and, cooling down, forms the so-called pegmatite veins . They consist of quartz and feldspar, and sometimes contain accumulations mica, precious stones (topaz, aquamarine, etc.), beryllium and lithium minerals, tin, tungsten, uranium.

Magmatic gases with valuable compounds dissolved in them not only accumulate in residual magma chambers, but can also seep through already solidified walls. So they penetrate into the surrounding cooling magma chamber of the rock. In this case, chemical reactions can occur between the filtered hot gases and the surrounding rock. Especially rapidly they flow between hot magmatic gases and calcareous rocks. In the course of such reactions along the periphery of massifs of cooling igneous rocks, in the zone of their contact with limestones, the so-called skarns . They are made up of minerals lime, silicon and aluminum. In addition, minerals often accumulate in skarns. iron, copper, lead, zinc, tungsten, boron.

But not all magmatic gases react at depth with rocks. Most of them, due to high pressure, rush through the cracks and pores of rocks up to the surface of the Earth. At the same time, the mineralized vapors are gradually cooled, liquefied and turned into hot mineral water - hydrotherms . They continue to climb porous permeable rocks. With further cooling of hot mineral waters, compounds of valuable and other elements dissolved in them precipitate. Filling the cracks of rocks, they form veins of minerals. Part of the fluid elements reacts with the minerals of the rocks and is deposited, forming mineral deposits that replace these rocks. Such deposits formed by deposits of hot mineral waters in the bowels of the Earth are called hydrothermal . Large amounts of ores are associated with this very important group of endogenous mineral deposits. copper, lead, zinc, tin, tungsten and other valuable items.

Exogenous deposits formed under the influence of geological processes near the surface of the Earth. They are formed during long-term changes in rocks as they move from the interior to the surface of the Earth. Such slow or sudden catastrophic uplifts of individual sections of the earth's crust have occurred in all geological epochs and continue to this day. At the surface of the Earth, rocks under the influence of temperature fluctuations and water flows are mechanically destroyed into small and tiny fragments. Under the influence of water, oxygen and carbon dioxide, they decompose chemically, changing their composition. The products of such destruction are carried away by water flows into the rivers and, settling on their bottom, form well-known river deposits. gravel, sand and clay. At the same time, some chemically resistant, non-oxidizing, solid and heavy minerals accumulate in the lower bottom part of river sediments, forming placers . Placers can concentrate only heavy minerals with a specific gravity of more than 3. Therefore, it is in the form of placers that deposits are known. gold, platinum, pewter, wolframite etc.

A significant part of the mineral mass in river water in the form of silt or in a dissolved state is carried out into the seas and oceans. The scale of such a removal is enormous. Thus, the Volga carries 25.5 million tons of material suspended in water into the Caspian Sea, the Amu Darya into the Aral Sea - 215 million tons, the Amazon into the Atlantic Ocean - about 1000 million tons. In the oceans and seas, minerals precipitate and accumulate on the bottom. These minerals come from the continents, under the influence of gravity, as a result of the chemical action of salty sea water, or in connection with life marine organisms. This is how thick layers are created rocks of sedimentary origin , among which are layers of sedimentary minerals. In addition to such well-known sedimentary rocks as sands, clays, limestones, ore deposits are common iron, manganese, aluminum, phosphorites, coal and oil.

On the surface of the Earth, mineral deposits are also formed as a result of the dissolution and removal of a part of the substance by groundwater, and sparingly soluble valuable mineral compounds accumulate in the remainder. For example, in a rock consisting of calcium and aluminum compounds, calcium minerals can dissolve and be removed with water, and compounds will accumulate in the residue. aluminum - bauxites - valuable ore for the production of this metal. Such deposits are called residual. Among them, in addition to bauxites, deposits are known iron ore, nickel ore, phosphorus compounds .

Part of the solute may again be deposited underground from groundwater as it penetrates through permeable rocks. The resulting deposits are called infiltration . Among infiltration known deposits nickel, copper, gold, uranium.

If rocks and mineral deposits enclosed among them sink into the depths of the Earth, they are affected by the pressure of the strata lying on them and the internal heat of the Earth. Under their influence, rocks and minerals change, are transformed into metamorphic , such as gneiss or schist. In this case, metamorphic mineral deposits may arise (“metamorphosis” - change). These include both pre-existing, but subjected to intensive changes in the body, and arose again due to metamorphism. These include, for example, deposits marble, roofing slates, mica, graphite, garnets.

One of the most valuable sources of energy for the world industry at the present time are the solid Mankind is unlikely to be able to do without them. Among other things, the brilliant Dmitry Ivanovich Mendeleev said: “You can also heat with banknotes.” The scientist meant that it would be more useful to use these resources for the synthesis of the substances required by man.

Modern science constantly confirms his correctness. Oddly enough, but in many respects we owe to the ancient flora the riches that lie deep underground. It was the ancient ferns and trees that formed over time many useful resources. By the way, what minerals were formed from ancient plants? Well, let's find out!

General characteristics of fuel types

All of these fuels contain huge amounts of carbon. All of them were formed from plant remains, which had been affected for millions of years. high blood pressure and high temperature. Some ancient plant fuels are well over 650 million years old. Approximately 80% of these fossils were formed during the Tertiary period. It is to these times that we owe the fact that mineral resources still provide us with everything we need.

The main feature of their formation should be considered the fact that at that time there was still little oxygen on the planet, which now oxidizes organic matter very quickly, but there is a lot of carbon and compounds based on it. Sedimentary rocks quickly conserved huge masses of substances in the thickness of the earth.

In order for you to better navigate this issue, we have prepared a table. Minerals are far from randomly located in the bowels of the earth.

However, among some scientists, the theory of the abiogenic origin of many fossil fuels is popular, which explains their occurrence by a combination of various factors that led to the appearance of complex carbon compounds from simple inorganic substances.

This point of view also has its right to life, but most scientists are still sure that the vast majority of deposits have exactly biological nature occurrence. Well, what minerals were formed from ancient plants? We will talk about this now.

Importance for industry and people

As we have already said, many of these substances are a real storehouse for the modern chemical industry. The same coal contains many compounds, which in other cases can be obtained only as a result of complex and expensive synthesis. For example, humic acids, which are not so common in nature and are quite difficult for artificial synthesis, are massively obtained from cheap and widespread brown coal.

In principle, economic geography will tell you about all this. Minerals play a crucial role in shaping the normal production economy of any country.

It should be remembered that the full use of many plant resources is possible only if a person is well aware of the nuances of their formation. First, we will consider the coals we have already mentioned more than once, since the process of their formation is very interesting. Coals, like other major minerals of plant origin, were formed by various plants in the process of their death.

Characteristics of the formation of humus coals

A very long time ago, when giant dinosaurs still roamed the Earth, beautiful lush forests grew in vast expanses. The conditions for their growth and development were ideal: there is a lot of organic matter in the soil, and carbon dioxide prevails in the atmosphere. However, these same conditions contributed to the fact that the plants died off very rapidly. Their parts fell to the ground, where they quickly decomposed, since they were not protected in any way from the oxidizing action of air.

The combination of all these factors led to a very rapid decomposition of cellulose. Giant masses of vegetation turned into a real "cocktail" of humic substances, diluted with small amounts of resins, waxes and paraffins. However, all this mass was quickly decomposed by microorganisms, and therefore there was no particularly rapid accumulation of organic matter at that time. The main mineral reserves appeared somewhat later.

So how was coal formed directly?

In the manner described above, dry peat was formed, which is still sufficient on the surface of our planet at the present time. As a rule, no further metamorphoses occurred to him, since most often he was covered with a layer of sand and earth, reliably preserving organic matter from the effects of oxygen and microorganisms. Such a mass was extremely plastic, and therefore there was no further separation or mixing.

Since there was very little undecomposed organic matter in the peat thickness, there were no further decay processes. Thus, the temperature in the thickness of the layers always remained at the same level.

pressure and time...

However, over time, the layers gradually compacted due to caking. Gradually, humic acids were converted into humites, resins underwent a decarboxylation process, and only waxes remained unchanged for thousands of years. This is how brown humus coals were formed. There are especially many of them in the Krasnoyarsk Territory. These are the region's most abundant minerals (and an important source of income, of course).

Under the influence of a whole range of environmental factors, their gradual metamorphosis took place, as a result of which hard humus coals were obtained. The main role in this process belongs to high pressure and no less high temperature. Under these conditions, humic acids began to rapidly decompose, resins and waxes underwent natural polymerization.

All this led to the synthesis of infusible, completely insoluble compounds. It is thanks to them that this grade of coal has survived to this day. It lies at relatively shallow depths, and therefore, given slightly different physical and chemical properties, it would inevitably be washed out. And what minerals were formed from ancient plants, in addition to the humus coal described above?

About the process of formation of mixed type coals

It should be noted that in nature the process of formation of pure humus compounds proceeded extremely rarely. Much more often there was a mixed process. Scientists suggest that he went in several directions at once. As a rule, all this happened at the bottom of ancient reservoirs, on the site of which mineral deposits are now located.

Humic substances were gradually brought there with rainwater and slowly, over the course of centuries, settled on the bottom. Plankton, which actively developed with such an abundance of organic matter, gradually mixed with all this mass. But things could have been completely different.

After powerful hurricanes and heavy rains hit the land, a huge amount of humic substances and various mineral compounds fell into the water bodies. At first, it was heavy minerals that settled at the bottom, and humic acids acted on them as powerful oxidizing agents. Gradually, all this mass was subjected to polymerization. Since there was very little oxygen at the bottom of the reservoirs, the substances eventually came under the influence of the dehydration process. This is how coal of mixed composition was formed.

These minerals of Russia are extremely common in the Eastern part of our country.

On the chemical composition of coals

In general, their composition is not particularly diverse: carbon, hydrogen, oxygen, nitrogen and sulfur. The difference is only in the mass fraction of all these substances, since it is precisely by their percentage that one can confidently determine not only the type of fossil fuel, but even the region of its origin and extraction. In order for you to have at least an approximate idea of ​​\u200b\u200bthis issue, we will analyze the composition of the average brown humus coal.

Classification of substances that make up coals

The most typical substances that are part of any of its varieties are called coal formers. Here is their complete list:

• Oddly enough, squirrels. During the hydrolysis of coal, scientists noticed that the resulting mixture contains a certain amount of amino acids. The presence of these substances in the thickness of the layers of fossil fuels is explained quite simply: these are protozoa preserved in ancient times, as well as the remains of more highly developed organisms. In any case, many mineral deposits often boast a collection worthy of a paleontological museum.
• Of course, cellulose. This complex carbohydrate, which is the main building material of any vegetable form of life, makes up a considerable weight part of both coals and oil shale (we will talk about them below).
• Waxes, which we have repeatedly mentioned. They are esters of some carboxylic acids and aliphatic alcohols.
• resins. This is a very complex mixture of all the same carboxylic acids, as well as saponifiable and non-saponifiable substances. Under certain specific conditions, they are easily decarboxylated and rapidly polymerized. They are a kind of “link” for coal, as they hold its components together during the primary compression process.

It is the almost identical composition of all fossil fuels that speaks of their vegetable and partially animal origin. Advocates of the abiotic occurrence of the same oil fail to find sufficiently convincing arguments with which to refute these factual data. In any case, any map of minerals (organic) will show that their deposits are mainly located in the places of ancient seas rich in organic matter.

Basic information about coal mining

The characteristics and methods of this process fully depend on the depth of the formations. If this does not exceed one hundred meters, then an open, quarry method of development is possible. It often happens that with an increase in the depth of the cut, the shaft method becomes more economically feasible.

On the territory of our country, the level of the deepest mine is approximately 1200 meters. Any map of Russia's minerals will show that most of them are in Siberia. This region is deservedly considered a real pantry, a granary of nature.

Other important substances

It should be noted that accumulations of substances of great industrial value are often found in coal seams. These include some valuable geological rocks (marble, for example), huge amounts of methane, as well as rare, trace elements. For example, some varieties of brown coal contain a lot of germanium, without which the modern radio-electronic industry is unthinkable, since it is on its basis that many types of semiconductors are created.

in modern industry

Long gone are the days when this type of mineral was used exclusively as a fuel. As we have already noted, some rare chemical elements are extracted from it, coal serves as a raw material for the production of many types of plastics. It has been known since the Second World War that artificial gasoline can be made from it.

It was these minerals in Russia that largely ensured the intensive growth of industry after the revolution. They also help keep the economy at a consistently high level.

oil shale

It is a solid vegetable origin from the group of solid caustobioliths. The main feature of slates, which provided them with such a high popularity in last years, is the resin included in their composition. It is obtained by distillation. Its value lies in the fact that in terms of its physical and chemical properties it is very close to oil, but at the same time the cost of its production is much lower than the oil field.

Differential Composition

The main difference between shale and all the same coal is that it contains more minerals. Its organic part is kerogen. Only in the highest quality shale does its share reach 70%, while in all other cases the organic content does not exceed 30%. Kerogen is the fossil remains of the oldest unicellular algae.

That part of them that has not lost traces of its cellular structure over the centuries is thallomoalginite. Accordingly, completely degraded are called colloalginite. In addition, in shales it is quite often possible to find even parts higher plants that have been on our planet since time immemorial.

Here are some minerals formed from ancient plants. We hope that from this article you have received all the information you were interested in.

As a child, I dreamed of becoming a geologist. I wanted to know everything about the riches of the geosphere. It seemed that it was in the depths of the earth's crust that all the secrets of the universe were hidden. Unfortunately, this profession has bypassed me. But the childish curiosity still lingers.

The concept of "Minerals"

PI is the natural wealth of the Earth, which people extract from the depths of the earth's crust or from its surface. These include oil, sand, gas, etc.

The earth's crust is formed by rocks that are made up of minerals. Minerals are natural bodies that are made up of atoms and molecules. These include quartz, salt, diamond and others.

Mineral classification

Igneous rocks are brought to the surface of the earth's crust along with magma. Such minerals and rocks differ in density. These include: iron, copper and other ores.

Sedimentary rocks are found on the surface of the earth. They were formed in the process of long-term accumulation of elements or as a result of the destruction of mountains. These include, for example, limestone, sandstone, crushed stone.

Organic sedimentary rocks are formed from the remains of plants and animals accumulated over many years. These include: shell rock, oil, etc.

According to the physical state, PI is distinguished:

• solid (gold);
• liquid (mercury);
• gaseous (hydrogen sulfide).

Depending on the use and composition of PIs, they are divided into ore and non-metallic (construction and combustible).

The use of oil in everyday life

I have always wondered what gives us such a discussed mineral as oil. It turns out that most of the household items consists of it. For example, in my apartment there is a TV, a toothbrush, a computer and a printer, plastic bags, synthetic clothes... All these items are made of plastic and contain “ black gold».

When refining oil, it is divided into many fractions. From these parts, at various stages of processing, fuel, cosmetic items, plastics, etc. are obtained.

Minerals are not limitless! We must protect our planet from the unreasonable use of natural resources!

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Since I live in a region rich in coal deposits, I could not help but be interested in the question of how coal was formed. The information that I found turned out to be very interesting, so I’ll tell you not only about what are minerals, but also describe in detail the process of formation of coal.

What does the term "minerals" mean?

This term refers to those that are of value to humans. minerals and rocks. According to the nature of origin, it is customary to distinguish the following types of these resources:

• sedimentary- this group includes fossil fuels, such as coal and oil;
• igneous- represent this group of metals;
• metamorphic such as marble or limestone.

What is hard coal

Almost until the 70s of the last century, this type of fuel had the status of the most common energy carrier, however, was later replaced by other species. Despite this, it is in great demand, primarily in metallurgy, as the main resource for the production of pig iron. Like most other types of energy carriers, it is a modified substance of organic nature - remains of ancient plants. This process took place over millions of years through the influence of various factors.

How coal was formed

Most of the extracted resource by its formation refers to 300-350 million years ago when huge masses of organic matter accumulated in the absence of oxygen. This process can be described as follows:

• formed at the beginning peat layer, usually in wetlands;
• over time, the layer increased, which means that increased pressure on the bottom;
• enormous pressure pushed out oxygen, which eventually led to the formation compressed peat- coal.

As a rule, the greater the depth peat layers, the higher the pressure, and hence the higher the quality of the coal seam. There are the following main types of this fossil:

• brown- for its formation, a layer of sediment up to a kilometer was needed;
• stone- in this case, the original substance experienced a pressure of 3 kilometers of sediment;
• anthracite- pressure over 7 kilometers of sediment.

However, this does not mean that high-quality fuel lies at great depths, on the contrary, tectonic processes caused the rise of a valuable resource to the surface, which made its extraction available.

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What do gold and coal have in common? It would seem that gold is an expensive metal from which beautiful jewelry is made. A sign of luxury and elegance. And coal is a hard mineral, black and dirty. It is used as a fuel. But there is one common concept that unites these two objects - both of thembelong to minerals. Now I will explain everything in detail.

Useful Finds

What can be found in the bowels of our earth? Sometimes almost on the very surface, and sometimes very deep, natural minerals and rocks are hidden from our eyes. They are attributed to minerals. They are widely used by people in various fields of activity. May differ in properties and states. There are:

• gaseous(inert gases and natural combustibles);
• solid(peat, salt, ores, coal);
• in liquid state(mineral waters and oil).

Since ancient times, people have extract and use minerals. The first attempts to extract them originated with the ancient Egyptians. Over the centuries, more and more new types of minerals have been explored, and since the 18th century, their extraction has significantly gained momentum, new deposits have been discovered. This was facilitated by the development of the world of modern technologies.

One of methods how minerals are mined open, in quarries. As a result, ravines are formed. Coal is mined in the mines, the depth can reach up to 1200 m. Oil is obtained gushing and pumping method.

Not all natural resources exist in unlimited quantities. There are those that are renewed, and there are those that can end in our nature at a certain moment (for example, coal, oil). Therefore, it is necessary to choose the right approaches to the process of extracting natural minerals and use modern technologies in the search for places of origin.

The oldest metal

The oldest metal considered gold. It is quite rare, and therefore the price is high. The largest deposits of gold are in South Africa, the United States, as well as in China, Peru and Australia. Mined his washing, amalgamation and cyanidation methods. There are also large deposits of gold in Russia. The period of the "Gold Rush" is known in history. When Alaska was sold by Russia to America and large deposits of this precious metal were discovered in it.

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At one time, I read the fairy tales of P. P. Bazhov. They opened the beauty for me Ural Mountains rich in minerals, and especially gems. I also wanted to have my own malachite box. Later I learned about the Ural village of Murzinka, a world-famous deposit of semi-precious stones.

The term minerals

Organic and mineral formations located in the earth's crust are called minerals. Physical Properties and chemical composition allow a person to use minerals for their needs, that is, to benefit. Minerals form three groups: metallic (iron, copper, tin), combustible (peat and coal, oil and gas), non-metallic (salt, clay, apatite).

Non-metallic minerals also include minerals of the gem group. These are rare and therefore very expensive stones.

The Russian land is rich in gems; 27 types of valuable stones lie in its depths. Most of the deposits are located in the Urals.

Ural - pantry of minerals

is a treasure trove of minerals. And if the periodic table has almost 120 elements, then 50 of them are mined in the Urals. This is where most of the useful elements that are so necessary for the life of our country. The most important of them are:

• ore, since most of both ferrous and non-ferrous metals are mined from it. Most of all ore reserves are located in the Urals;
• oil and gold also mined in the Urals. Their reserves are not so great (20% of all sources of this raw material in the country), but they are still not depleted. Moreover, scientists are finding new deposits of these minerals;
• rhinestone. Many local businesses are busy processing it.

Precious and colored stones are a special group of rare and valuable minerals. is rightfully proud of its bright green emeralds and golden topazes, red-green alexandrites and soft lilac amethysts.

The products of local lapidaries are famous all over the world. Yes, the village Murzinka became famous for its gem mines: amethyst and tourmaline, beryl and blue topaz, which brought Murzinka worldwide fame. A unique find was found here - topaz blue color, called "Victory", weighing more than 43 kilograms! Now this unique mineral is in the State Protection of Russia. And the Ural alexandrites are recognized as the best in the world! This is the rarest mineral. Therefore, its search, extraction and transportation are under the strictest control. Alexandrite is famous for changes his usual green color(under artificial lighting) to purple-pink. And of course, the visiting card of the Ural gems - malachite.

A lot of malachite was found in copper mines. There was a time when its production amounted to several thousand pounds a year! A huge piece of malachite weighing 250 tons was found in 1835.

Here they are Ural gems that brought world fame to the Urals and Russia!

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I am from Kuzbass, and, in my opinion, it sounds proud. My region specializes in mining. All the men in my family were and continue to be engaged in their booty. Until recently, I only knew about coal, because Kuzbass - the coal capital. My acquaintance with a variety of minerals began a year ago, after my husband changed his job and, in addition to coal, began to extract other minerals. He brought home the most beautiful specimens, and at that moment I decided to get acquainted with the minerals in more detail.

Definition of minerals

Minerals are rocks, as well as minerals, which find their application in national economy . From my own experience, I would like to note that the most beautiful of minerals are minerals.

There are types of minerals:

• gas, this group includes methane, helium and gases;
• liquid– mineral waters, oil;
• solid, the most large group and it includes coal, salt, granite, ores, marble.

How minerals are mined

There are two methods of mining. Open and closed. Open pit mining, from where, by the way, my husband brings interesting specimens.

In a closed way, coal is mined in mines. This is very dangerous view mining, but in our region closed mining is the most common.

The most beautiful minerals that I have met

Granite. Hard, dense rock, used in construction.

Quartz. Has a very diverse color scheme from white to black. It is used in optics, radio equipment, electronic devices.

Copper. Ductile metal, used in electrical engineering, in the production of pipes, in jewelry alloys.