Coal mining in Appalachia may bring to mind the archetypal soot-covered miner working deep underground. But in the last 30 years, a big percentage of coal mining has been done under the sun.
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Compared with underground mining, the advantages of surface mining mainly include the following points. (1) Large mine production capacity. ... The load capacity of surface use trucks is continuously increasing and electric wheel trucks are widely used in surface mines. Steep slope railway transportation system (the slope is 40–50%) has …
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Underground mining of steep seams in India. rsingh1_2@yahoo Thick Seam Mining and Strata Mechanics Department 2 ... However, parameters like: depth cover, surface/sub-surface constraints, multi seam mining, steepness, contiguity and thickness of the seam are becoming more important with changing geo-mining conditions of the …
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Many recent examples have shown that rockfalls can occur in underground steep coal mines. The stratigraphic circumstances, block formation mechanism, and …
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This study investigates the transition from surface to underground mining at the Sepon Gold mine. The stability of surface slopes is assessed prior to commencing underground operations. Stope mining is adopted based on ore body characteristics and geological features. Finite element numerical analysis, employing the Generalized …
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To solve this difficult technological problem that predicts the surface subsidence that induced by deep mining of large steep deposit. Through understanding engineering geological characteristics and mining conditions for a certain mining area, the three-dimensional simulation model of deep mining with a high degree similarity in …
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Learn about different types of surface mining methods, such as strip mining, contour mining, and area mining, with examples and diagrams. Find out how to select the best …
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This movement and deformation characteristic of overburden strata can provide theoretical basis for the similar mining condition. Key words: fault; steep-inclined coal seam; numerical simulation; overburden distortion 1 Introduction In the underground mining process, the deformation of overburden strata caused by mining activity and …
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Aiming at the practice of the uniting of surface mining and underground mining and the interaction, the thin plate model of mined slope was established with the influence analysis of underground mining to slope, distortion and stress distribution law studied. ... Zhou Wei, etc. Research on key influence factors of end-slope stability for …
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The excavating process in open pit mines result in cone-shaped volume in which the bench area becomes progressively smaller as the pit deepens with the walls formed by cascading benches (Fig. 2.1a). The flat surface of the bench remaining on the pit wall is called the berm (Fig. 2.1b). The berms create safe zones in case of rocks spalling …
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Underground mining activities and rainfall have potential important influence on the initiation and reactivation of the slope deformations, especially on the steep rock slope. In this paper, using the discrete element method (UDEC), numerical simulation was carried out to investigate deformation features and the failure mechanism of the …
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This is too steep an angle for rubber-tyred vehicles to climb and too flat for a gravity assist rock flow. ... Equipment for Underground Mining. ... Standard on Fire Protection for Self-propelled and Mobile Surface Mining Equipment. NFPA 121. Quincy, MA: NFPA. —. 1996b. Flammable and Combustible Liquids Code. NFPA 30.
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Mining Operations. Data obtained from the Mine Safety and Health Administration (MSHA) indicated a total of 889 underground (6.0%) and 13,982 surface (94.0%) mining operations. Employees. A total of 55,617 employees, or 57,222 full-time equivalent (FTE) employees, were reported to MSHA as working at underground …
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The stratigraphic circumstances in underground steep coal mines are unique compared with surface mining. First, blocks are formed in the coal wall of SDCSs, and the height difference between the upper and lower ends of a working face is over 70 m (Fig. 2 (a)).Second, the position where the block detaches from the coal wall is highly …
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Table 2 summarises angle values for several cases studied at the coalfields of northwestern Spain. Fig. 4, Fig. 5 summarise the results of the case described in Rodrı́guez and Toraño [9] in which the subsidence produced by the extraction of a 3.00–3.50 m thick near-vertical seam (75°), using the sublevel caving method, is analysed. The height of …
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The endwalls of surface mines will suffer double disturbance of surface mining and underground mining, with the coal mined by the latter. And it will influence …
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Such deposits can be extracted by either surface or underground mining depending on which the methods turn out to be more favorable economically; ... It is employed on many ore deposits and partially for mining coal from dipping and steep deposits. In this case the quarry is deepened gradually and its ultimate depth may be as …
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Surface coal mining in the steep terrain of the central Appalachian coalfields involves removing parts or all of mountaintops to expose buried seams of coal and disposing the excess in adjacent valleys. Learn more about surface coal mining. 1. …
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mining, a form of surface mining used in steep landscapes, is now the dominant form of coal extraction12,13 and land cover ... 1995, 2005, 2011. In some cases underground mines occur deep below mountaintop mines. However, the geomorphic impact from deep mines on the surface is much more localized49 and relatively small …
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Hazard classification and stability analysis of high and steep slopes under different working conditions are studied using the Shizhuyuan non-ferrous metal mine …
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The impact of surface mining on surface runoff was reviewed in articles published from 2009 to 2020 indexed in Science Direct, Scopus, Web of Science, and Scielo databases. Measurement methods, quantities, influencing factors and trends of surface runoff in mining areas are presented and research gaps, challenges, and …
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DOI: 10.1016/S1365-1609(00)00046-0 Corpus ID: 129646198; Probabilistic analysis of subsidence-induced strains at the surface above steep seam mining @article{Torao2000ProbabilisticAO, title={Probabilistic analysis of subsidence-induced strains at the surface above steep seam mining}, author={Javier Tora{~n}o and Rafael …
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•Ore body is steep ... Surface subsidence in the case of shallow mines. Rock-bursts underground, ... Underground Mining Methods Flow Chart (modified from Brown, 2003)
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These down dip operations are susceptible to water inflow, both from underground and surface sources, requiring pumping and/or other control measures. 2. ... The restrictions imposed by steep-dip mining substantially reduce production and recovery as compared to flat-seam mining. Creative mining methods have been evaluated to …
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Coal is produced in Appalachia via both surface and underground mining. Mining methods have changed and advanced over nearly two centuries, improving worker safety and environmental performance. ... thereby creating a near-vertical highwall above the mine "bench," and a steep outslope of material that had been cast down the …
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With steep slopes of the surface and steeply dipping deposits, the systems of the second group (deepening systems) are employed. When working deposits with complicated topographic and geological conditions of bedding, systems of both groups can be used in a quarry. ... Gogolewska A (2011) Surface and underground mining …
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The coordination between end-slope underground mining and surface coal mining is mainly composed of underground mining time, working face moving and shifting time, new roadway excavating time and surface mining-and-dumping advancing speed, as shown in Fig. 2.In order to minimize the mutual interaction between UMM and surface …
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The hazard must result from some AML-related feature(s) such as steep or unstable banks, hidden underwater ledges, or rocks or debris on the bottom. ... is surface burning. UMF Underground Mine Fire. Any AML-related continuous smoke, haze, heat, or venting of hazardous gases from underground mine coal combustion posing a danger to public …
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DOI: 10.1016/J.PROEPS.2011.09.002 Corpus ID: 129848533; Study on Stability of Surface Mine Slope Influenced by Underground Mining below the Endwall Slope @article{Peng2011StudyOS, title={Study on Stability of Surface Mine Slope Influenced by Underground Mining below the Endwall Slope}, author={Hongge Peng and Qingxiang …
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Stope design is a core discipline within mining engineering. This study analyzes the current state-of-the-art of stope design through a survey addressed to mining industry professionals.
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A large number of geological disasters such as collapse, landslide and debris flow occur in Southwest China, and coal mining is replacing natural forces as the main factor leading to disasters. The most significant external feature of mining slopes in the mountainous areas of Southwest China is that the terrain is high and steep. In this …
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Coal mining - Underground mining: In underground coal mining, the working environment is completely enclosed by the geologic medium, which consists of the coal seam and the overlying and underlying strata. …
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Surface subsidence can also result from underground mining, which can be significant depending on mine size, orebody shape, mining excavation method and mine …
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Surface coal mining in the steep terrain of the central Appalachian coalfields includes: mountaintop removal, contour, area, highwall, and; auger mining. Operations are concentrated in: ... In some cases underground mining also produces enough spoil to require the construction of valley fills.
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Many examples have shown that rockfalls can occur in underground coal mines. The presence of rockfalls in the long walls of a steeply dipping coal seam …
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