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A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to reduce their environmental impact.
The word quarry can also include the underground quarrying for stone, such as Bath stone.
Types of rock extracted from quarries include:
Stone quarry is an outdated term for mining construction rocks (limestone, marble, granite, sandstone, etc.). There are open types (called quarries, or open-pit mines) and closed types (mines and caves).
For thousands of years, only hand tools had been used in quarries. In the 18th century, the use of drilling and blasting operations was mastered.
The method of removal of stones from their natural bed by using different operations is called quarrying. Methods of quarrying include:
Following steps are used in the blasting process;
Many quarry stones such as marble, granite, limestone, and sandstone are cut into larger slabs and removed from the quarry. The surfaces are polished and finished with varying degrees of sheen or luster. Polished slabs are often cut into tiles or countertops and installed in many kinds of residential and commercial properties. Natural stone quarried from the earth is often considered a luxury and tends to be a highly durable surface, thus highly desirable.
Quarries in level areas with shallow groundwater or which are located close to surface water often have engineering problems with drainage. Generally the water is removed by pumping while the quarry is operational, but for high inflows more complex approaches may be required. For example, the Coquina quarry is excavated to more than 60 feet (18 m) below sea level.
To reduce surface leakage, a moat lined with clay was constructed around the entire quarry. Groundwater entering the pit is pumped up into the moat. As a quarry becomes deeper, water inflows generally increase and it also becomes more expensive to lift the water higher during removal; this can become the limiting factor in quarry depth. Some water-filled quarries are worked from beneath the water, by dredging.
Many people and municipalities consider quarries to be eyesores and require various abatement methods to address problems with noise, dust, and appearance. One of the more effective and famous examples of successful quarry restoration is Butchart Gardens in Victoria, British Columbia, Canada.
A further problem is pollution of roads from trucks leaving the quarries. To control and restrain the pollution of public roads, wheel washing systems are becoming more common.
Many quarries naturally fill with water after abandonment and become lakes. Others are made into landfills.
Water-filled quarries can be very deep, often 50 ft (15 m) or more, and surprisingly cold, so swimming in quarry lakes is generally not recommended. Unexpectedly cold water can cause a swimmer's muscles to suddenly weaken; it can also cause shock and even hypothermia. Though quarry water is often very clear, submerged quarry stones, abandoned equipment, dead animals and strong currents make diving into these quarries extremely dangerous. Several people drown in quarries each year. However, many inactive quarries are converted into safe swimming sites.
Such lakes, even lakes within active quarries, can provide important habitat for animals.
Underground hard-rock mining refers to various underground mining techniques used to excavate "hard" minerals, usually those containing metals, such as ore containing gold, silver, iron, copper, zinc, nickel, tin, and lead. It also involves the same techniques used to excavate ores of gems, such as diamonds and rubies. Soft-rock mining refers to the excavation of softer minerals, such as salt, coal, and oil sands.
Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, is a surface mining technique of extracting rock or minerals from the earth from an open-air pit, sometimes known as a borrow.
Portland Stone or Portland Stone Formation is a limestone formation from the Tithonian stage of the Jurassic period quarried on the Isle of Portland, Dorset, England. The quarries are cut in beds of white-grey limestone separated by chert beds. It has been used extensively as a building stone throughout the British Isles, notably in major public buildings in London such as St Paul's Cathedral and Buckingham Palace. Portland Stone is also exported to many countries—being used for example in the United Nations headquarters building in New York City.
A gravel pit is an open-pit mine for the extraction of gravel. Gravel pits often lie in river valleys where the water table is high, so they may naturally fill with water to form ponds or lakes. Old, abandoned gravel pits are normally used either as nature reserves, or as amenity areas for water sports, landfills and walking. In Germany former gravel or sand pits that have filled up with water are known as Baggersee and popular for recreational use. In addition, many gravel pits in the United Kingdom have been stocked with freshwater fish such as the common carp to create coarse fishing locations. Gravel and sand are mined for concrete, construction aggregate and other industrial mineral uses.
A tunnel boring machine (TBM), also known as a "mole", is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They may also be used for microtunneling. They can be designed to bore through hard rock, wet or dry soil, or sand. Tunnel diameters can range from one metre (3.3 ft) (micro-TBMs) to 17.6 metres (58 ft) to date. Tunnels of less than a metre or so in diameter are typically done using trenchless construction methods or horizontal directional drilling rather than TBMs. TBMs can be designed to excavate non-circular tunnels, including u-shaped, horseshoe, square or rectangular tunnels.
Surface mining, including strip mining, open-pit mining and mountaintop removal mining, is a broad category of mining in which soil and rock overlying the mineral deposit are removed, in contrast to underground mining, in which the overlying rock is left in place, and the mineral is removed through shafts or tunnels.
Dimension stone is natural stone or rock that has been selected and finished to specific sizes or shapes. Color, texture and pattern, and surface finish of the stone are also normal requirements. Another important selection criterion is durability: the time measure of the ability of dimension stone to endure and to maintain its essential and distinctive characteristics of strength, resistance to decay, and appearance.
Drilling and blasting is the controlled use of explosives and other methods such as gas pressure blasting pyrotechnics, to break rock for excavation. It is practiced most often in mining, quarrying and civil engineering such as dam, tunnel or road construction. The result of rock blasting is often known as a rock cut.
Construction aggregate, or simply aggregate, is a broad category of coarse- to medium-grained particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are the most mined materials in the world. Aggregates are a component of composite materials such as concrete and asphalt; the aggregate serves as reinforcement to add strength to the overall composite material. Due to the relatively high hydraulic conductivity value as compared to most soils, aggregates are widely used in drainage applications such as foundation and French drains, septic drain fields, retaining wall drains, and roadside edge drains. Aggregates are also used as base material under foundations, roads, and railroads. In other words, aggregates are used as a stable foundation or road/rail base with predictable, uniform properties, or as a low-cost extender that binds with more expensive cement or asphalt to form concrete. Although most kinds of aggregate require a form of binding agent, there are types of self-binding aggregate which do not require any form of binding agent.
A drifter drill, sometimes called a rock drill, is a tool used in mining and civil engineering to drill into rock. Rock drills are used for making holes for placing dynamite or other explosives in rock blasting, and holes for plug and feather quarrying.
The following outline is provided as an overview of and topical guide to mining:
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass.
Stoping is the process of extracting the desired ore or other mineral from an underground mine, leaving behind an open space known as a stope. Stoping is used when the country rock is sufficiently strong not to collapse into the stope, although in most cases artificial support is also provided.
Decomposed granite is a kind of granite rock that is weathered to the point that the parent material readily fractures into smaller pieces of weaker rock. Further weathering yields material that easily crumbles into mixtures of gravel-sized particles known as grus that further may break down to produce a mixture of clay and silica sand or silt particles. Different specific granite types have differing propensities to weather, and so differing likelihoods of producing decomposed granite. It has practical uses that include its incorporation into roadway and driveway paving materials, residential gardening materials in arid environments, as well as various types of walkways and heavy-use paths in parks. Different colors of decomposed granite are available, deriving from the natural range of granite colors from different quarry sources, and admixture of other natural and synthetic materials can extend the range of decomposed granite properties.
Digging, also referred to as excavation, is the process of using some implement such as claws, hands, manual tools or heavy equipment, to remove material from a solid surface, usually soil, sand or rock on the surface of Earth. Digging is actually the combination of two processes, the first being the breaking or cutting of the surface, and the second being the removal and relocation of the material found there. In a simple digging situation, this may be accomplished in a single motion, with the digging implement being used to break the surface and immediately fling the material away from the hole or other structure being dug.
The geology of Maine is part of the broader geology of New England and eastern North America.
The geology of Virginia began to form 1.8 billion years ago and potentially even earlier. The oldest rocks in the state were metamorphosed during the Grenville orogeny, a mountain building event beginning 1.2 billion years ago in the Proterozoic, which obscured older rocks. Throughout the Proterozoic and Paleozoic, Virginia experienced igneous intrusions, carbonate and sandstone deposition, and a series of other mountain building events which defined the terrain of the inland parts of the state. The closing of the Iapetus Ocean, to form the supercontinent Pangaea added additional small landmasses, some of which are now hidden beneath thick Atlantic Coastal Plain sediments. The region subsequently experienced the rifting open of the Atlantic Ocean in the Mesozoic, the development of the Coastal Plain, isolated volcanism and a series of marine transgressions that flooded much of the area. Virginia has extensive coal, deposits of oil and natural gas, as well as deposits of other minerals and metals, including vermiculite, kyanite and uranium.
The Schevenhütte quarry is a former slate quarry in Stolberg-Schevenhütte. Unique Schevenhütte natural stone was quarried here presumably from the Middle Ages until 2008. In the 20th century until it was closed down, the quarry was called "Kaspar Müller I Quarry". It is located on the northern edge of the Eifel at the southern end of Schevenhütte. Geologically, it is part of the outermost foothills of the Venn saddle, where very old rocks from the latest Ordovician period are exposed. These rocks are the oldest in North Rhine-Westphalia. As a special feature, the so-called "Schevenhütter Schichten" dip very straight in the quarry area and were thus worth mining. "Schevenhütter Naturstein" was quarried mainly in two varieties, a greenish and a red variety. Basically, the stone from the middle and upper Wehebach layers was roughly processed and sold on site. The "Schevenhütter Schiefer" was used in a variety of ways throughout the region, including as ornamental and rough building material, but also as walking slabs and as gravestones.
S.K Duggal "Building Materials" (2003) 3rd revised edition Quarries