# everything about >>mining



## احمد عباس الخطيب (3 سبتمبر 2009)

*Mining*
is the extraction of *valuable* *mineral*s or other geological materials from the earth, usually (but not always) from an *ore* body, *vein*, or (*coal*) seam. Materials commonly recovered by mining include *bauxite*, *coal*, *copper*, *diamond*s, *iron*, *gold*, *lead*, *manganese*, *magnesium*, *nickel*, *phosphate*, *platinum*, *rock salt*, *silver*, *tin*, *titanium*, *uranium*, and *zinc*. Other highly useful materials that are mined include *clay*, *sand*, *cinder*, *gravel*, *granite*, and *limestone*. Any material that cannot be grown from agricultural processes must be mined. Mining in a wider sense can also include extraction of *petroleum* and *natural ga*
.​*History*

*The oldest known mine in the archaeological record is the "Lion Cave" in Swaziland. At this site, which has a radiocarbon age of 43,000 years, paleolithic humans mined for the iron-containing mineral hematite, which they presumably ground to produce the red pigment ochre.*

Sites of a similar age where *Neandertal*s may have mined *flint* for weapons and tools have been found in *Hungary*​_Another early mining operation was the *turquoise* mine operated by the *ancient Egyptians* at Wady Maghareh on the *Sinai Peninsula*. Turquoise was also mined in *pre-Columbian* America in the Cerillos Mining District in *New Mexico*, where a mass of rock 200 feet (60 m) in depth and 300 feet (90 m) in width was removed with stone tools; the mine dump covers 20 acres (81,000 m²).

Black *gun powder* in *mining* was first time used in a shift Bartolomej in mines under the town *Banská ?tiavnica*, *Slovakia* in 1627. There is 12000 kilometers of tunnels under this small town drived for a 1000 years.
Mining techniques
Mining techniques can be divided into two basic excavation types:​__Surface *mining*_ 
is a type of *mining* used to extract deposits of *mineral* resources that are close to the surface. In most forms of surface *mining*, heavy equipment, such as *earthmover*s, first remove the overburden (the soil and rock above the deposit). Next, huge machines such as *drag line excavator*s extract the *mineral*. Surface *mining* generally leaves large devastated areas called *spoil bank*s unless the land is *recovered* and it has a huge negative effect on the local *ecosystem* and *the environment*. There are four main forms of surface *mining*.
Types of surface mining​*Strip Mining*

*Strip mining* is the practice of *mining* a seam of mineral *ore* by first removing all of the soil and rock that lies on top of it (the *overburden*). It is similar to open-pit *mining* in many regards. Strip *mining* is also used to extract the oil-impregnated sand in the *Athabasca Tar Sands*.
Strip mining is only practical when the ore body to be excavated is relatively near the surface. Since colossal quantities of material often need to be removed, the excavating machinery used in strip mining is often among the largest such equipment ever constructed; *drag line excavator*s and *bucket-wheel excavator*s are common examples.
There are two forms of strip mining - area strip mining, which is used on fairly flat terrain, to extract deposits over a large area. Contour strip mining, usually used in hilly terrain, involves cutting terraces in mountainsides following the contour of the land.​*Open-pit mining*

*Open-pit mining* refers to a method of extracting *rock* or *minerals* from the earth by their removal from an open pit or *borrow*. The term is used to differentiate this form of *mining* from extractive methods that require tunneling into the earth. Open-pit mines are used when deposits of commercially useful *minerals* or *rock* are found near the surface; that is, where the _overburden_ (surface material covering the valuable deposit) is relatively thin or the material of interest is structurally unsuitable for tunneling (as would be the case for *sand*, *cinder*, and *gravel*). Where *minerals* occur deep below the surface—where the overburden is thick or the *mineral* occurs as veins in hard *rock*— underground *mining* methods are used to extract the valued material. Open-pit mines are typically enlarged until the *mineral* reserve is exhausted.​*Mountaintop removal*

*Mountaintop removal* (MTR) is a relatively new form of *coal* *mining* that involves the mass restructuring of earth in order to reach *sediment* as deep as 1,000 feet below the surface. *Mountaintop removal* requires that the targeted land be first *clear-cut* and then leveled by *dynamite*. The *debris* created is typically scraped into a _valley fill_ - a practice that has twice been ruled illegal by a *federal judge* in accordance with the *Clean Water Act*.​*Dredging*

*Dredging* is a method often used to bring up underwater mineral deposits. Although dredging is usually employed to clear or enlarge *waterway*s for boats, it can also recover significant amounts of underwater minerals relatively efficiently and cheaply.
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## احمد عباس الخطيب (3 سبتمبر 2009)

Open-pit mining
*Open-pit mining* refers to a method of extracting *rock* or *minerals* from the earth by their removal from an open *pit* or *borrow*. The term is used to differentiate this form of *mining* from extractive methods that require tunneling into the earth. Open-*pit* mines are used when deposits of commercially useful *minerals* or *rock* are found near the surface; that is, where the _overburden_ (surface material covering the valuable deposit) is relatively thin or the material of interest is structurally unsuitable for tunneling (as would be the case for sand, cinder, and gravel). Where *minerals* occur deep below the surface—where the overburden is thick or the *mineral* occurs as veins in hard *rock*— underground *mining* methods are used to extract the valued material. Open-*pit* mines are typically enlarged until the *mineral* reserve is exhausted.

Open-pit mines that produce *building material*s are commonly referred to as *quarries*. People in some English-speaking countries are not likely to make a distinction between an open-pit mine and other types of open-cast mines, such as *quarries*, *borrows*, *placers*, and *strip mines*.
When they are no longer productive for extraction of material, open-pit mines are sometimes converted to *landfill*s for disposal of solid wastes. However, some form of water control is usually required to keep the mine pit from becoming a *lake*.


Materials typically extracted from open-pit mines include:
_Clay_ 
_Coal_ 
_Coquina_ 
_Gravel_ and _stone_ (stone refers to bedrock, while gravel is unconsolidated material, as found in _glacial_ or _fluvial_ deposits) 
_Granite_ 
_Gritstone_ 
_Gypsum_ 
_Limestone_ 
_Marble_ 
_Metal ores_: such as _copper_, _iron_, _gold_, and _molybdenum_ 
_Sand_ 
_Sandstone_​*2_ Sub-surface mining*

_Sub-*surface mining* or underground mining_ refers to a group of techniques used for the extraction of valuable *minerals* or other geological materials from the earth. In contrast to the other main type of *excavation*, *surface mining*, sub-*surface mining* requires equipment and/or manpower to operate under the surface of the earth.​*Types of sub-surface mining*


_Drift mining_​
_Slope mining_​
_Shaft mining_​
_Hard rock mining_​
_Borehole mining_​
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## احمد عباس الخطيب (3 سبتمبر 2009)

Extractive metallurgy
The science of *extractive metallurgy* is the study of beneficiation and extraction of valuable metals and minerals from their ores. Although *extractive metallurgy* is all encompassing, *mineral processing* or mineral dressing is often the term used for the study of processing coal, industrial minerals and precious stones, as these are not metals.

Environmental effects
Modern mining companies in many countries are required to follow strict environmental and reclamation codes, ensuring the area mined is returned to its original state, or an even better environmental state than before mining took place. Past mining methods have had, and methods used in countries with lax environmental regulations continue to have, devastating environmental and public health effects. The result can be unnaturally high concentrations of some chemical elements over a significantly wider area of surface. Combined with the effects of water and the new 'channels' created for water to travel through, collect in, and contact with these chemicals, a situation is created where mass-scale contamination can occur.


Mining industry


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## احمد عباس الخطيب (3 سبتمبر 2009)

Extractive metallurgy
The science of *extractive metallurgy* is the study of beneficiation and extraction of valuable metals and minerals from their ores. Although *extractive metallurgy* is all encompassing, *mineral processing* or mineral dressing is often the term used for the study of processing coal, industrial minerals and precious stones, as these are not metals.

Environmental effects

Modern mining companies in many countries are required to follow strict environmental and reclamation codes, ensuring the area mined is returned to its original state, or an even better environmental state than before mining took place. Past mining methods have had, and methods used in countries with lax environmental regulations continue to have, devastating environmental and public health effects. The result can be unnaturally high concentrations of some chemical elements over a significantly wider area of surface. Combined with the effects of water and the new 'channels' created for water to travel through, collect in, and contact with these chemicals, a situation is created where mass-scale contamination can occur

Mining industry

While exploration and mining can sometimes be conducted by individual entrepreneurs or small business, most modern-day mines are large enterprises requiring large amounts of capital to establish. Consequently, the industry is dominated by large, often multinational, mostly publicly-listed companies.


Mine Planning Software
One of the most dramatic changes in the mining industry has been the role that sophisticated three dimensional 3-D mine planning software packages have had. Initially relatively simple tasks - like rendering graphic images of drill holes - meant that it became more easy for surveyors, geologists, mine planners, mining engineers and other technical staff to manipulate and visualize data. However, in recent years the range of integrated mine planning tools have meant that massively complex models can be built to optimize the extraction and processing of mineral resources.



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## طارق البخاري (4 سبتمبر 2009)

بسم الله والحمد لله والصلاة والسلام على رسول الله

بارك الله فيك على هذا الجمع الطيب المبارك-بإذن الله-.


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## geoghada (21 يونيو 2010)

الله يبارك فيك..... تسلم


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## geoghada (21 يونيو 2010)

شكرا جزيلا أخي العزيز... كنت في أمس الحاجة لمثل هذه المحاضرة... جزاك الله عنا خيراً


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## احمد عباس الخطيب (21 أغسطس 2010)

شكرا على مروركم الكريم


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