Citizendia
Your Ad Here

Cutting of laterite brickstones, Angadipuram, India
Cutting of laterite brickstones, Angadipuram, India

Laterite (from the Latin word "later" meaning brick or tile) is a surface formation in hot and wet tropical areas which is enriched in iron and aluminium and develops by intensive and long lasting weathering of the underlying parent rock. Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26 WikipediaNaming Weathering is the decomposition of earth rocks, Soils and their Minerals through direct contact with the planet's Atmosphere. Parent rock refers to the original rock from which something else was formed Nearly all kinds of rocks can be deeply decomposed by the action of high rainfall and elevated temperatures. The percolating rain water causes dissolution of primary rock minerals and decrease of easily soluble elements as sodium, potassium, calcium, magnesium and silicon. A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific Sodium (ˈsoʊdiəm is an element which has the symbol Na( Latin natrium, from Arabic natrun) atomic number 11 atomic mass 22 Potassium (pəˈtæsiəm is a Chemical element. It has the symbol K (kalium from qalīy Atomic number 19 and Atomic mass 39 Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 Magnesium (mægˈniːziəm is a Chemical element with the symbol Mg, Atomic number 12 Atomic weight 24 Silicon (ˈsɪlɪkən or /ˈsɪlɪkɒn/ silicium is the Chemical element that has the symbol Si and Atomic number 14 This gives rise to a residual concentration of more insoluble elements predominantly iron and aluminium. Laterites consist mainly of the minerals kaolinite, goethite, hematite and gibbsite which form in the course of weathering. Kaolinite is a Clay mineral with the chemical composition Al 2 Si 2 O 5( OH)4 Goethite, named after the German Polymath Johann Wolfgang von Goethe, is an iron bearing oxide mineral found in soil and other low temperature environments Hematite, also spelt hæmatite, is the Mineral form of Iron(III oxide (Fe2O3 one of several Iron oxides Gibbsite, Al(OH3 is one of the mineral forms of Aluminium hydroxide. Moreover, many laterites contain quartz as relatively stable relic mineral from the parent rock. Quartz (from German) is the most abundant Mineral in the Earth 's Continental crust (although Feldspar is more common in The iron oxides goethite and hematite cause the red-brown color of laterites. Altogether there are sixteen known Iron Oxides and oxyhydroxides Goethite, named after the German Polymath Johann Wolfgang von Goethe, is an iron bearing oxide mineral found in soil and other low temperature environments Hematite, also spelt hæmatite, is the Mineral form of Iron(III oxide (Fe2O3 one of several Iron oxides

Cretaceous laterite exposed in Makhtesh Gadol, Israel.
Cretaceous laterite exposed in Makhtesh Gadol, Israel. The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of Makhtesh Gadol (המכתש הגדול lit The Big Crater) is a Makhtesh, a geological erosional landform of Israel's Negev For a topic outline on this subject see List of basic Israel topics.

Laterite covers have mostly a thickness of a few meters but occasionally they can be much thicker. Their formation is favoured by a slight relief which prevents erosion of the surface cover. Topography ( topo-, "place" and graphia, "writing" is the study of Earth 's Surface features or those of Planets Laterites occurring in non-tropical areas are products of former geological epochs. Lateritic soils form the uppermost part of the laterite cover; in soil science specific names (oxisol, latosol, ferallitic soil) are given for them. Soil science is the study of Soil as a Natural resource on the surface of the Earth including soil formation, classification and mapping Oxisols are an order in USDA soil taxonomy, best known for their occurrence in Tropical Rain forest, 15-25 degrees north and south of the Equator

In geosciences only those weathering products are defined as laterite, which are geochemically - mineralogically most strongly altered. Earth science (also known as geoscience, the geosciences or the Earth Sciences) is an all-embracing term for the Sciences related to the planet They must be distinguished from less altered saprolite which has often a similar appearance and is also very widespread in tropical areas. Saprolite (from Greek σαπρος =putrid + lite is the name for a chemically weathered rock Both formations can be classified as residual rocks.

Laterites can be as well soft and friable as firm and physically resistant. Indurated varieties are sometimes cut into blocks and used as brickstones for house-building—the term derives from Latin later = brickstone. A brick is a block of Ceramic material used in Masonry construction laid using mortar. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. Khmer temples were often constructed of laterite, but by the 12th century Khmer architects had become skilled and confident in the use of sandstone as the main building material. The Kingdom of Cambodia ( formerly known as Kampuchea (, transliterated: Preăh Réachéanachâkr Kâmpŭchea) is a country in South East Sandstone is a Sedimentary rock composed mainly of Sand -size Mineral or rock grains. Most of the visible areas at Angkor Wat are of sandstone blocks, with laterite used for the outer wall and for hidden structural parts that have survived for over 1000 years. Angkor Wat (or Angkor Vat) (អង្គរវត្ត is a Temple complex at Angkor, Cambodia, built for King Suryavarman II Hardened laterite varieties are also applied for the construction of simple roads (laterite pistes). Nowadays solid lateritic gravel is readily put in aquaria where it favors the growth of tropical plants.

Lateritization is economically most important for the formation of lateritic ore deposits. An ore is a volume of rock containing components or Minerals in a mode of occurrence that renders it valuable for mining Bauxite which is an aluminium-rich laterite variety can form from various parent rocks if the drainage is most intensive thus leading to a very strong leaching of silica and equivalent enrichment of aluminium hydroxides above all gibbsite. Bauxite is the most important Aluminium Ore. It consists largely of the minerals Gibbsite Al(OH3 Boehmite γ-AlO(OH and

Lateritization of ultramafic igneous rocks (serpentinite, dunite, or peridotite containing about 0,2 - 0,3% nickel) often results in a considerable nickel concentration. Ultramafic (also referred to as ultrabasic) rocks are igneous and meta -igneous rocks with very low Silica content (less than 45% generally Igneous rocks (etymology from Latin ignis, fire are rocks formed by solidification of cooled Magma (molten rock Serpentinite is a rock composed of one or more Serpentine Minerals Minerals in this group are formed by serpentinization a hydration and metamorphic Dunite (ˈduːnaɪt or /ˈdʌnaɪt/ is an igneous, Plutonic rock, of Ultramafic composition with coarse-grained or Phaneritic A peridotite is a dense coarse-grained Igneous rock, consisting mostly of the minerals Olivine and Pyroxene. Nickel (ˈnɪkəl is a metallic Chemical element with the symbol Ni and Atomic number 28 Two kinds of lateritic nickel ore have to be distinguished: A very iron-rich nickel limonite or nickel oxide ore at the surface contains 1-2% Ni bound in goethite which is highly enriched due to very strong leaching of magnesium and silica. Limonite is an ore consisting in a mixture of hydrated Iron(III oxide-hydroxide of varying composition Beneath this zone nickel silicate ore can be formed, frequently containing > 2% Ni that is incorporated in silicate minerals primarily serpentine. The silicate minerals make up the largest and most important class of rock-forming Minerals They are classified based on the structure of their silicate Ion group The serpentine group describes a group of common rock-forming hydrous Magnesium Iron phyllosilicate (()3 Minerals they In pockets and fissures of the serpentinite rock green garnierite can be present in minor quantities, but with high nickel contents - mostly 20-40%. Garnierite is the name for a green nickel ore which is found in pockets and fissures of weathered ultramafic rocks ( Serpentinite, Dunite, Peridotite It is bound in newly formed phyllosilicate minerals. The silicate minerals make up the largest and most important class of rock-forming Minerals They are classified based on the structure of their silicate Ion group All the nickel in the silicate zone is leached downwards (absolute nickel concentration) from the overlying goethite zone. Absence of this zone is due to erosion.

See also

References

External links

Dictionary

laterite

-noun

  1. A red hard or gravel-like soil or subsoil formed in the tropics that has been leached of soluble minerals leaving insoluble iron and aluminium oxides and hydroxides; used to make bricks and roads.
© 2009 citizendia.org; parts available under the terms of GNU Free Documentation License, from http://en.wikipedia.org
 Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic