First to delve into the nature of the minerals, we know that a mineral is a natural substance, homogeneous inorganic origin, chemically defined ( within certain limits), has properties and characteristics generally has a crystal structure (crystalline form).
A mineral has an ordered arrangement of atoms of elements that is made, and this results in development flat surfaces called faces. If the mineral has been able to grow without interference can generate geometric features, known as crystals. Mineral
as mineralogy and geology, are chemical elements and compounds formed by inorganic processes, ie they are structures formed by natural processes of inorganic origin, physical properties and chemical composition homogeneous and chemically defined. The science that deals with the study of minerals is called mineralogy.
Training
mineral formation is the result of chemical and physical processes that take place in all geological times and still continue to manifest.
Minerals arise through three main processes:
- magmatic
- metamorphic
- sedimentary
magmatic processes: leads to the formation of minerals by solidification magma. Given the speed with which the cooling of magma occurs, it can be three situations:
If healing occurs at depth, under high pressure, gases and slow cooling magmatic crystallization favor
Sometimes the crystallization of various minerals is not simultaneous, but it happens on a selective and complete as the temperature decreases.
magmas are generally very deep but can sometimes reach the surface, giving rise to greater volcanic activity, in this case the magma solidifies creating a compact rock mass, sometimes grainy.
metamorphic process:
is any structural change, mineralogical and chemistry that occurs in the rocks under the effect of temperature, pressure and fluid circulation.
There are two types of metamorphism: regional and thermal metamorphism.
thermal metamorphism, magmatic intrusions phenomena of metamorphism causes incandescent rocks. The most characteristic minerals in this type of metamorphism are: garnet, sillimanite, cordierite, Vesuvian, spinel, pyroxene, pyrite, etc..
regional metamorphism: develops large areas of the earth's crust subject to subsidence and dislocations. Are three function of depth are: epizone, mesozona and catazona.
- Epizone: between 5,000 and 7,000 m deep. This area shows: talc, albite, epidote, hematite, titanite, and lamellar fibrous minerals.
- Mesozona: between 7,000 and 12,000 m in depth. In this area are: biotite, muscovite, kyanite, placioclasa, epidote, etc..
- Catazona: between 12,000 and 20,000 m in depth. In this area are: orthoclase, biotite, plagioclase, pirosenos, olivine, garnet, graphite.
migmatite: Roca high grade metamorphism.
Sedimentary Process:
Most of the minerals to be found in sedimentary rocks from the mechanical erosion and chemical alteration of existing rocks. These processes occur without the action of high pressures or temperatures.
can be classified taking into account the same criteria used by the sedimentary rocks, thus, we have:
* mechanical deposit minerals are mainly detritus, transported and deposited undergo a process of consolidation or cementation eg limonite ..
* chemical deposit minerals are formed by precipitation of substances found in solution.
mineral deposit * Organic Chemistry and Biochemistry, directly involved in training the action of living organisms.
Conglomerates are sedimentary clasts large (greater than 2mm) and a matrix or cement that encompasses.
Sandstone is a sedimentary rock composed of sand-sized clasts (2 to 0.02 mm) and a matrix or cement that encompasses.
Informational Video
Rocks and Minerals:
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