Mineral part of the soil

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In general, land mass consists of 2 parts:
1) Mineral
2) Organic part.
Mineral part of the soil may be formed from erosion of rocks, its dispersing and sometimes full burning of organic remainders. Its organic may be formed from decaying of plant and organic remainders. In each land mass mineral and organic parts are not in equal amount. As usual its mineral part is much than organic part but sometimes organic parts are much than mineral part sin swamps. As we know, because of mineral part of the land is gathered from rocks directly and as mineral part of the land of the rock is dependent either from mineralogical structure or from chemical structure we must get acquainted with “mother rocks" of the basic land comprehensively.
"Eruption rocks" is first from rocks forming land. These rocks are considered as we know frozen liquid magma of rocks. Eruption rocks play very little part in forming of the land, because these rocks are seen in buried conditions under the young geological sediments. But very seldom it is noted that eruption rocks form a land as a mother rocks in mountainous zones. e.g: eruption rocks in the Small Caucasus, Armenia, the Crimea and the Ural form a land. The 2nd group from mother rocks is considered "Metamorphic rocks". These rocks are from those, which were formed under high temperature and pressure. Metamorphic rocks play very small part in forming of a land like eruption rocks, because these rocks self were changed under the influence of foreign factors. At last, 3rd group of rocks are called as "Sediment rocks». These rocks play a big part in land forming. As we know, sediment rocks consist of air and sediment rocks in water environment. It is necessary to note especially that mostly land types have been generated in the inside of territory of the USSR from sediment rocks. The sediment which has great important in land forming is young part of rocks. The 4th circumference sediment is sediment rock. Depending on conditions of generating of rocks of this period they are divided in to two groups:
1. Continental sediments.
2. Sea sediments.
Continental sediments have been spread mostly in our country but sea sediment can be found in the basins of old sea and seashores.
Continental sediments of the 4th period are divided into following groups:
1. Ice sediments.
2. Water- ice sediments
3. Lake- ice sediments.
4. Lake sediments.
5. Alluvial sediments.
6. Lake- alluvial sediments.
7. Proluvial sediments.
8. Eluvial forming.
9. Deluvial forming.
10. Eluvial-deluvial sediments.
11. Eol sediments.
1. Ice sediments: various moraines are related to it. As we know moraine rocks have been brought in the time of motion of the giant glaciers and are deemed to be gathered rocks. If rocks are settled under rocks it is called as “bottom moraines”, and settled in sides it is called as “sine moraines”, and if settled in top it is called as “last moraines”. In general, moraine sediments are very different for its mechanical structure. In most cases moraine sediments are consisted of clayey sandy, sand and stony sediments.
2. Water-ice sediments: These sediments consist of sediments which have been brought with the help of the glacier waters and gathered. For mechanical composition they are stony sediments. In some cases water-ice sediments so gathers that forms of definite relief forms. But in some cases water-ice sometimes form relief in the form of crooked line. Such relief is called "oz". In other cases water-ice sediments are separated in vast area that forms naked, small stony point. This form of relief called is "zandr"
3. Lake-ice sediments: These sediments are found in glacier lakes and at many times they were spread at the slopes of relief. One of main features of these sediments is forming stripy clay.
4. Lake sediments: Such type of sediments is met mostly in lowland and plains. In most cases they settle in pit areas. Their typical signs are absence of stripes in sediments. By its mechanical structure they are very heavy clays.
5. Alluvial sediments: These sediments have been spread in the valleys of river and creeks, and these sediments were formed from sediments that appeared from overflow of rivers and gathering there. By its mechanical structure they are very different and with layers. Thus sometimes layers of sand, clay and stone replace each other.
6. Lake-alluvial sediments: They are mixed with lake and alluvial sediments. They have been spread mostly in lowland regions. By mechanical structure they are sometimes heavy clayey and sandy.
7. Proluval sediments: They are sediments that were brought by temporary floods. They are mostly located in upland and mountains regions. They are by mechanical structure stony, pebbly. Sometimes proluvial sediments forms of definite relief, too. e.g: Coming cone of the rivers that we knew in regions of foothills is an example of it.
8. Eluvial sediments: If it is not carried out by any natural means to another place in the result of erosion of the rocks, such eroded products are called ad eluvial creations. Eluvial creations are different for their structure and appearance. So, eluvial creations in high mountain peaks are in form of naked stones and in hot damp lowland areas such sediments are in form of clay. One of specific feature of eluvial sediments is link of these sediments with rocks. Structure of rock, its color and mineralogical structure are same like in eluvial sediments. Eluvial sediments in Azerbaijan can be met in mother rock of the land of Great and Small Caucasus zone.
9. Deluvial sediments: They are sediments that gathered at result of rain and taking away of eroded items for a short distance. Deluvial sediments are mostly spread in the slopes of the mountains, slopes of the relief foothills. Such sediments are rather fine. By mechanical structure they are in clayey form. As it was mentioned above basic difference in deluvial sediments is presence of national stripes in their structure.
10. Eluvio-deluvial sediments: As we mentioned above in some cases eluvial and deluvial sediments are met in nature in mixed form. In such cases they are called eluvio-deluvial sediments. Mixed forming of sediments depends on conditions of their creation. Relief of the place takes plays big part here especially. e.g. If eluvial sediments remain in the place of erosion depending on sloping place of the place, they can be buried together with deluvial sediments. And namely in such form these rocks are mixed. Eluvio-deluvial sediments are mostly found in foothill zones.
11. Eol sediments: They have been brought by winds with the help of the settled remainders. Eol sediments cover sandy and sand sediments mostly. Such sediments can be found in desert and semi-deserts, and sometimes at seashores. Eol sediments sometimes can be gathered so that they can form relief. "Barkhan" in deserts, sandy hills at seashores are clear examples of that. Many scientists consider loss sediment, which spread in the USSR (Central Asia), as one of eol sediments. So, sediments of IV periods mentioned by us above take part in land forming as mother rocks either at world scales and territory of the USSR. Depending on the variety of the sediments, land cover is different either for its mineralogical structure or its mechanical structure. It was noted that in the result of conducted researches, usually creative lands over moraine has sour reaction, alkali, neutral reactions over gathered lands with deluvial sediments.

Structure of erupted and metamorphic rocks.
Mineralogical composition of the rocks has big influence in land forming. These minerals have directly linked to mechanical structure of land while its forming and nutrition items that may appear in land. Therefore, we have to study minerals in these rocks closely, too. Generally minerals have been spread to two groups of erupted and metamorphic rocks.
1. Basic mineral
2. Minor minerals.
Basic mineral specify the kind of rocks.
In spite of less spreading in structure of the rock the minor mineral forms food matters in structure of the land in future. Basic minerals include below mentioned minerals:
1. Quartz.
2. Field spars
3. Field spars
4. Pyroxene and amphibole
5. Olivine
6. Micas
Except quartz all other minerals belong to complicated and sometimes simple silicates.
Minor minerals:
1. Mineral of Apatite and pyrite has been included here. These two minerals as we mentioned are origin for food items in land. Apatite mineral form in the land compound of the salts of phosphoric acid and phosphorus. Pyrite minerals forms sulphuric acid and sulphuric salts.
2. Quartz: This colorless mineral is waterless oxide of silicon acid.
Field spars: These minerals are salts of H2 Al2 Si6 O16 (alimo-silicon) acids. In some cases hydrogen is replaced with potassium in the alimo-silicon acid, then its forms K2 Al2 S16 O16 orthoclase mineral, and if replaced with natrium it becomes N2 Al2 S16 O16 albite.
Field spars: These another chlorine in structure mineral from (the) aluminum and to meet to chlorine and sulphuric salt is met in the structure of these minerals except aluminum. Minerals included in this group:
Leucite, K2 Al2 Si4 O8
Sodalite 3Na2 Al2 S2 O8
Nepheline Na2 Al2 S2 O8
Pyroxene and amphibole: This group includes salts of complex and simple silicates. Most spread minerals are:
Enstatite- Mg Si O3
Diopside- Ca Mg Si2 O6
Wollastant- Ca Si O3
Aucit -Ca (Mg Fe) Si2 O6 + Ca Al2 Si O6
Horimblent- Ca (Mg Fe)3 Si4 O12
Peridot- (Mg Fe)2 SiO4

This group of minerals has been spread to the basic rocks mostly.
Micas: This group of minerals is dived into 2 big groups:
1. Muskovite.
2. Biotite.
Muscovite mineral has open color but biotite has dark blackish color.

II-Level MINERALS.
Minerals were found less developed in this group but they have great importance in structure of soil. Because these will be a source of the food matter in the land in future. This group include minerals of pyrite and apatite. Pyrite mineral creates sulphuric acid and sulphuric salts in soil and apatite mineral forms mostly basic phosphorus compounds in soils.
Process of erosion of rocks.
Each rock depending on geological condition if comes over surface of earth they are subjected to force of foreign forces of nature. Under influence of these foreign forces rocks change their both physical and chemical structure. At result new sediment which does not resemble to the primary rock is formed, too that is called products of "erosion". If rocks change its structure and composition under influence of foreign forces, then this process is called as “erosion process”. Depending on condition of breakage and reasons there 3 types of erosion:
1. Mechanical erosion
2. Chemical erosion
3. Biological erosion
Mechanical erosion: this erosion is a process of transforming to small particles being broken of rock under the physical influence. If mechanical erosion has one feature, it is to increase own surfaces by being eroded in rocks. Basic factors that create mechanical erosion are:
1. Changing of the temperatures.
2. Influence of the frozen waters.
As you know likewise all body rock can increase its volume under influence of the warmth, and in the light period of night a rock will reduce its volume. This process continues for long time in the nature and it has sometimes grown under influence of the temperature, depending on pressing sometimes, so cracks as thin hair form on them.
Forming in rocks of the thin cracks is dependent on their mineralogical structure. Because there is coefficient of swelling of each mineral according to them. Some mineral bring up volume under influence of the temperature, but it will less change a volume of others and being in structure of the rock of different mineral without doubt, shows that the same rock will be able to undergo to mechanical erosion quickly. Under influence of the temperature erosion is often met in dry and moderate climate countries. In the cold, moderate climate countries and Arctic, frozen waters at high upland zones have big influence in mechanical erosion of the rocks. Dampness of the atmosphere and rainfall are filtered waters gradually to deep layer of the rock in the cracks which have formed on rocks filter. In these regions water inside of these rocks gets frozen and turns to ice it widens its volume, so broadens emerged cracks on rocks, too. If rock becomes broken to pieces with the help of this kind of frozen waters, it is called “frost” erosion.
Besides aforementioned factors rocks become eroded with the help of the influence of the winds in the mechanical speed. Sand particles brought by winds gradually polish them. Winds mostly help to erode soft rocks: e.g. limestone. Such kind of erosion is met mostly in desert countries. One of the big factors of the mechanical erosion is influence of the glaciers.
When glaciers move, it shaves rocks gradually and they cause gradual partition of rocks. Mechanical erosion is met mostly in high mountains, Arctic and dry deserts. In some cases mechanical erosion is too strong that rocks occupy big areas.
Chemical erosion: Rocks can be eroded in nature chemically like mechanically, too. These two processes have close links between them. Even to separate them is not right. Because rocks will be eroded at the same time both mechanically and chemically. As it was mentioned above when rocks are eroded mechanically they increase their surface and create suitable conditions for chemical erosion.
It is possible to say so that mechanical erosion of rocks is a process of preparation for chemical erosion. Rocks in chemical erosion deeply change their composition and mineralogical structures. Basic factors creating chemical erosion are: water, carbon dioxide gas and oxygen. Water is counted as basic factors of the chemical erosion. Because with the help of water the influence of the carbon dioxide gas and oxygen increase. Moreover the water self has own direct influence, too. The first influence of water to rocks is its solve ability. Though solubility of rocks in water this process continues so long times in nature that water can wash out some items from rocks. Moreover, water gets into reaction with separate minerals transfers waterless minerals to forms of watered minerals. This influences to its physical structure, too. To be true, water loses its durability and gradually its solubility degree increases, too.
One of factors increasing the degree of solubility is carbon dioxide gas. If there is carbon dioxide gas in structure of the water, its solubility degree will be high. As we know, there is no "clear" water conception in the nature. These waters always are in conditions of saturated with carbon dioxide gas. Solubility degree of the water is very high, for example, all rivers carry out 4 billion kilograms of different salts to big environment sea every year. Frozen water solves not only rocks; it can split even rocks and can create very new various compounds. Ability to be broken to pieces of the water is dependent on its dissociation degree. Water is separated to ions being called HOH in the result of dissociation. Here H ion entering to reaction with bases in the rocks creates new compounds and so it deeply changes the chemical composition of the rock. Dissociation degree of the water is dependent on its temperature. Dissociation degree grows by increase of water temperature, too, e.g.:
0º-1
10º - 1,7
18º - 2,4
34º - 4,5
50º - 8,0
It is possible to come at such conclusion from figures that by increase of temperature ability of water to become broken to pieces increases, too. But chemical erosion of rocks in various climatic zones does not occur adequately, in cold, moderate, short summer seasons the chemical erosion is weak and in hot countries chemical erosion is strong. As we said chemical erosion creates new compounds in the structure of rocks. To make it clear we bring an example of field spar’s chemical erosion.

Orthoclase 1) K2 Al2 Si6 O16 + 2 H2 O + CO2 =
= H2 Al2 Si2 O8 • H2O + K2 CO3 + 4Si O2

Apartite 2) Ca Al 2 Si O8 + 2H 2 O + CO2 =
= H2 Al2 Si2 O8 • H2O + Ca CO3

Albite 3) Na2 Al2 Si6 O16 + H2O + CO2 =
= H2 Al2 Si2 O8 • Na2 CO3 + 4Si O2

Sodium
It is possible to come to such conclusion from reactions that we wrote above that if alimo-silicates gets eroded under water influence it can create new compounds: Free quartz forms CO2, sodium Na2 CO3, potash K2 CO3 and kaolin H2 Al2 Si2 O8 .H2O.
At result of chemical erosion kaolin forming process of field spars is called kaolinization process. SiO2 which have been formed in the reaction depending on condition of generation, sometimes have been solved and washed out by waters and sometimes settled in the form of waterless quartz and it procreates the basic part of the soil in future. But Kaolin matter is quite simple for composition. But under very high temperature and high dampness (tropical countries) only) kaolin matter becomes broken to pieces:
Fe (OH)2
Al (OH) 2
Any rock becomes broken to pieces to simple chemical salts, hydrates and oxides in the result of chemical erosion, e.g.: Ca CO3, Na2 CO3, Fe OH2, Al OH2, K2 CO3, Si O2 and so on. As we mentioned above one of the factors of chemical erosion is oxygen that forms an air. This factor can turn mineral being in structure of the rocks to another mineral by oxidizing them. To make it clear we can show an example of turning of magnet mineral to hematite mineral in the result of oxidizing of magnet mineral.
4Fe3 O4 + O2 = 6Fe2 O3 hematite
Because hematite mineral is very unstable it turns to iron hydrate under influence of the water.
Fe2 O3 + 3H2 O = 2Fe (OH)3 iron hydrate.
One more example is oxidizing of pyrite mineral.
Fe Si2 + O + H2 O =
Iron acid = Fe SO4 + H2s SO4 sulphate acid
Salt of FeSO4 which have been formed here turns to iron hydrate and then it is turned to the iron oxide.
But sulphate acid gets into reaction with bases of minerals and creates various sulphate salts. It turns out that rock forms new compounds in the result of chemical erosion under influence of the very different processes becoming broken to pieces. Generally, as rocks are various because of its structure they form in the process of erosion different erosion products. If basic rocks become eroded and basic rocks have spread the most clays, calcium carbonate, magnesium carbonate, iron hydrates in their erosion products. But these form SiO2 compounds from products. In contrary if acid rocks become eroded (like facet) the sand sediments can be found in SiO2 besides above mentioned compounds.
It is necessary to note especially that composition of the eroded product generally is dependent on stage of the erosion process. Products of erosion in the 1st stage (step) of the process of erosion are very rough. Mineral and rock crumbs are most weakly eroded in structure of it. Another instance: salts of calcium, magnet, and carbonate. But compounds of iron aluminum take very little place. If process of erosion continues till end in the rock, to be true at last stage contrarily very weak eroded mineral particles are found in the composition of erosion products and new chemical compounds are met very often. So it can be assumed that the structure of eroded products is dependent on age of that rock. Young rocks are eroded weakly and old rocks are eroded deeper. In view of that erosion products can be divided in 4 groups generally. Products of erosion concerning to the first group are those that one can find incompletely eroded or weak eroded mineral particles in composition of these products. The second group is called products of passage to erosion. One can find free quartz and clay in its structure. Third group of eroded products is called those products of final erosion. Both rock parts and mineral particles are eroded till the end and non-crystalloid silicate, hydrate, aluminum and iron hydrate can be found in the structure of these products. Fourth group of erosion products include carbonate, sulphate and phosphate salts. Erosion products of 1st and 2nd group have no such significant role in land forming process.




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