General information on mining
Mining refers to the actual extraction of valuable minerals or other geologic materials from the earth, usually from an ore body, vein, or (coal) seam. Any material that cannot be grown through agricultural processes, or created artificially in a laboratory or factory, is usually mined.
According to the broadest definition, mining is an industrial process of discovering, extracting and processing of all non-renewable resources . This broad definition of mining includes the extraction of metals such as copper, iron, uranium i.e., precious metals, non-minerals such as diamonds, phosphate, potash and the energy minerals such as coal, petroleum and natural gas.
The term “mining” comprises the recovery of oil and gas from wells; the extraction of metals, non-metallic minerals, coal, peat, oil shale and other hydrocarbons from the earth by different methods. There are two basic types of mining operations to extract mineral ores from the earth: open pitorsurface mining (quarries, opencasts or open pits) and underground mining. The mode of occurrence of the sought-for metallic substance governs to a large degree the type of mining that is practised. The problem of depth also affects the mining method. If the rock containing the metallic substance is at a shallow site and is massive, it may be economically excavated by a pit or quarry-like opening on the surface. Open pit mining involves drilling, blasting the ore and hauling it out of the pit in large trucks or in ore trains to crushers and then to the metallurgical plants.
Value of Mining
Mining activities have been carried out by humans for millenia.
Throughout history, mining products have shaped the course of civilization. Civilization passed from the stone age to bronze age, and has entered the age of iron and coal, the industrial revolution, and now the information age. In the information age we give little thought to the role mining plays in providing the products we take for granted in our daily lives. But cars, telephones, computers and television all begin with mining. So do the roads we drive on, the buildings we work in.
One way to understand the value of mining is to try to visualize a world without minerals, the products of mining. The world without minerals, for example, would be a world without motorized vehicles – cars, trucks, trains, ships, and airplanes – the basic structures of which, as well as the engines, are metal. Buildings would be based on wood, and limited amount of surface containing clay and stones. The large structures that characterize the twenty first century – skyscrapers, bridges, plants – would not exist because they require the products of mining - concrete, cement, stone, glass, and metal. Inside buildings, a world without mining, would mean no electrical appliances or office equipment. Stereos, computers and photocopiers all rely on multiple mining products.
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Coal
Coal has been mined for more than 1,000 years, and large-scale coal mining was developed during the Industrial Revolution and coal provided the main source of primary energy for industry and transportation in the West from the 18th century to the 1950s. Coal remains an important energy source, due to its low cost and abundance when compared to other fuels.
Although coal deposits exist in nearly every region of the world, commercially significant coal resources occur only in Europe, Asia, Australia, and North America. Commercially significant coal deposits originated in sedimentary rock basins, typically sandwiched as layers called beds or seams between layers of sandstone and shale.
When experts develop estimates of the world`s coal supply, they distinguish between coal reservesand resources.
Reservesare coal deposits that can be mined profitably with existing technology – that is, with current equipment and methods.
Resources are an estimate of the world’s total coal deposits, regardless of whether the deposits are commercially accessible. Exploration geologists have found and mapped the world’s most extensive coal beds. At the beginning
of 2001, global coal reserves were estimated at 984.2 billion metric tons, in which 1 metric ton equals 1,016 kg (2,240 lb).These reserves occurred in the following regions by order of importance: the Asia Passific, including Australia,29.7 percent,
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North America, 26.1 percent, Russia and the countries of the former USSR,
23.4 percent, Europe, including the former USSR, 12.4 percent, Africa and the Middle East, 6.2 percent, South and Central America, 2.2 percent.
Coal deposits in the United Kingdom, which led the world in the coal production until the 20th century, extend throughout parts of England, Wales, and southern Scotland. Coalfields in Western Europe underlie the Saar and Rurh valleys in Germany, the Alsace region of France, and areas of Belgium. Coalfields in central Europe extend throughout parts of Poland, The Czech Republic, and Hungary. The most extensive and valuable coalfields in Eastern Europe is the Donets Basin, between the Dnieper and Don rivers (in parts of Russia and Ukraine). Large coal deposits in Russia are being mined in Kuznetsk Basin in southern Siberia. Coal fields underlying northwestern China are among the largest in the world. Mining of these fields began in the 20th century.
What is Environmental & Engineering Geology?
Environmental and Engineering Geology is the application of geological science to engineering and construction of man-made structures, protection of environmental conditions, the public health, safety and welfare.
Environmental & Engineering Geologists apply geologic data, techniques, and principles to the study, characterization and analysis of:
- naturally occurring rock, soil materials, surface and subsurface fluids;
- geologic and hydrologic processes and their interaction with the natural and built environment;
- geologic, seismic and hydrologic hazards that can impact human health and the built environment, man-made impacts to soil, groundwater and surface water resources, and mitigation of such impacts.
Environmental & Engineering Geologists utilize specialized training and experience to provide quantitative information and recommendations. Environmental & Engineering Geologists work with and for public and governmental agencies – use planners, environmental specialists, architects, engineers, and property owners to provide geologic information on which they base decisions. Some of the major activities of Environmental & Engineering Geologists include:
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- Site characterization and analysis of soil and rock materials underlying foundations of all types of structures, transportation infrastructure, power generation and petroleum facilities.
- Evaluation of geologic hazards such as landslides, active faults and earthquakes, subsidence, collapsible soils, expansive bedrock, cavernous rock (karst), and liquefaction.
- Assessment, development, and protection of surface water and groundwater resources, investigation of contaminated soil, groundwater and surface water.
- Assessment and mitigation of radon, asbestos, and other naturally occurring
hazardous substances.
- Evaluation of geologic conditions (including ground water) affecting residential, commercial, and industrial land use and development.
- Construction geology including slope stability, dewatering, subdrainage.
- Characterization and assessment of geology, hydrology and potential
environmental impacts related to the geologic and hydrologic environment for environmental impact reports.
- and many others.
What is a computer?
A computer is a machine with an intricate network of electronic circuits that operate switches or magnetize tiny metal cores. The switches, like the cores, are capable of being in one or two possible states, that is, on or "Off; magnetized or demagnetized. The machine is capable of storing and manipulating numbers, letters, and characters (symbols).
The basic idea of a computer is that we can make the machine do what we want by inputting signals that turn certain switches on and turn others off, or magnetize or do not magnetize the cores.
The basic job of computers is processing of information. For this reason computers can be defined as devices which accept information in the form of instructions, called a program, and characters, called data. They perform mathematical and / or logical operations on the information, and then supply results of these operations. The program, or part of it, which tells the computers what to do, and the data, which provide the information needed to solve the problem, are kept inside the computer in a place called memory.
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It is considered that computers have many remarkable powers. However, most computers, whether large or small, have three basic capabilities.
First, computers have circuits for performing arithmetic operations, such as: addition, subtraction, division, multiplication, and exponentiation.
Second, computers have a means of communicating with the user. After' all, if we couldn’t feed information in and get results back, these machines wouldn’t be of much use. Some of the most common methods of inputting information are to use terminals, diskettes, disks, and magnetic tapes. The computer’s input device (a disk drive or tape drive) reads the information into the computer. For outputting information two common devices used are: a printer, printing the new information on paper, and a cathode- ray-tube display, which shows the results on a TV-like screen.
Third, computers have circuits which can make decisions. The kinds of decisions which computer circuits can make are not of the type: “Who would win the war between two countries?” or “Who is the richest person in the world?” Unfortunately, the computer can only decide three things, namely: Is one number less than another? Are two numbers equal? and, Is one number greater than another?
Application of computers
At present a great deal of the work force of most countries is engaged in creating, processing, storing, communicating, and just working with information. Computers have become commonplace in homes, offices, stores, schools, research institutes, plants.
The use of computers in business, industry, and communication services is widespread today. Computer-controlled robots are able to improve the quality of manufactured products and to increase the productivity of industry. Computers can control the work of power stations, plants, and docks. They help in making different decisions and in management of economy.
The work of banks depend upon computer terminals for millions of daily operations. Without these terminals, records of deposits and withdrawals would be difficult to maintain, and it would be impossible to make inquiries about the current status of customer accounts.
Computers form a part of many military systems including communication and fire control. They are applied for automatic piloting and automatic navigation. Space exploration depends on computers for guidance and research.
Computers find application in astronomy and upper atmosphere research. Weather forecasting, library information services can benefit from computers too.
It is interesting to note that computers are widely used in medicine. They became valuable medical diagnostic tools. Computers are used for optical scanning and image processing, ranging from pattern recognition to image processing. Technicians can operate computer tomography scanners, which combine x-rays with computer technology to give sectional views of the body of patients. The views then can be combined into a single image shown on the screen.
It should be noticed that learning on a computer can be fun. Students spend more time with computer-aided instruction performing the assigned task, as compared with conventional classroom.
At last air traffic control is impossible without computer application. It fully depends upon computer-generated information.
Many other uses of computers that we cannot imagine at present will become commonplace in the transition from an industrial to post-industrial, or information, society.
Computers in Our Life
Computer addicts are the minority of computer users but there is no doubt that more and more young people are computer literate. Computer studies is a subject in many schools and many young people have personal computers. About one in three hundred computer owners spend almost all their time using computers.
Ninety six per cent of them are males of all ages. All of them spend an average of twenty hours per week on home computers. The majority of the adults also use computers at work. All the computer addicts are very intelligent. They have been interested in science and technology from a very early age, and they are usually very shy people who like being alone.
Usage of computers gives them confidence. They love debugging and solving problems, developing programs and love learning programming languages. They learnt to communicate with other users through computer networks and the people they met in school and work think of them as of computer experts. A few spend their time "hacking" and one addict left a message on a computer of Buckingham House.
A survey in a school showed that fewer girls are interested in computers because girls are less likely to have a computer. Even if they have one, they use them less frequently than boys. Possibly it is because we think of computers as something to do with maths and science, which are traditionally "male" subjects. Possibly it is because most of the computer teachers are men, who give the girls less attention. Possibly parents think it is less important for girls to have computer skills.
Some parents worry about computer games because they think their children won't be able to communicate with real people in the real world. But parents do not need to worry. According to research computer addicts usually do well after they have left school.
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