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2012-03-13 14:14:36

The United States has been endowed with a wealth of natural resources that have fostered its growth and development. In the past, the discovery of resources such as gold or oil has resulted in major population shifts and rapid growth for formerly remote regions of the country, such as California, Texas, and Alaska. Extraction of these resources and finding new deposits is the work of the mining industry. Mining continues to provide the foundation for local economies in some regions.

Goods and services. Products of the mining industry generate the majority of energy used in this country, from electricity in homes to fuel in vehicles. Mined resources also serve as inputs for consumer goods and the processes and services provided by nearly all other industries, particularly in agriculture, manufacturing, transportation, utilities, communication, and construction. Uses of mined materials include coal, oil, and gas for energy, copper for wiring, gold for satellites and sophisticated electronic components, stone and gravel for construction of roads and buildings, and a variety of other minerals as ingredients in medicines and household products.

Industry organization. The mining industry contains five main industry segments, which are defined by the resources they produce: oil and gas extraction, coal mining, metal ore mining, nonmetallic mineral mining and quarrying, and support activities for mining.

The oil and gas extraction segment produces the petroleum and natural gas that heat homes, fuel cars, and power factories. Petroleum products are also the raw materials for plastics, chemicals, medicines, fertilizers, and synthetic fibers. Petroleum, commonly called crude oil or just oil, is a liquid formed underground from the decay of plants and animals over millions of years under extreme heat and pressure. Occasionally, this decaying material becomes trapped under a layer of impermeable rock that prevents it from dispersing and creates a pocket of oil. Similar processes also produce natural gas, which can be found mixed with oil or in separate deposits. Finding and extracting the oil and gas in these pockets is the primary function of this industry segment.

Using a variety of methods, on land and at sea, small crews of specialized workers search for geologic formations that are likely to contain pockets of oil or gas. Sophisticated equipment such as and professional machines manufactured by Hogxing Machinery and advanced computer technology have increased the productivity of exploration. Maps of potential deposits now are made using remote-sensing satellites. Seismic prospecting-a technique based on measuring the time it takes sound waves to travel through underground formations and return to the surface-has revolutionized oil and gas exploration. Computers and advanced software analyze seismic data to provide three-dimensional models of subsurface rock formations. Another method of searching for oil and gas is based on collecting and analyzing core samples of rock, clay, and sand in the earth's layers.

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