An increased global supply of minerals is essential to meet the needs and expectations of a rapidly rising world population. This implies extraction from greater depths. Autonomous mining systems, developed through su...An increased global supply of minerals is essential to meet the needs and expectations of a rapidly rising world population. This implies extraction from greater depths. Autonomous mining systems, developed through sustained R&D by equipment suppliers, reduce miner exposure to hostile work environments and increase safety. This places increased focus on "ground control" and on rock mechanics to define the depth to which minerals may be extracted economically. Although significant efforts have been made since the end of World War II to apply mechanics to mine design, there have been both technological and organizational obstacles. Rock in situ is a more complex engineering material than is typically encountered in most other engineering disciplines. Mining engineering has relied heavily on empirical procedures in design for thousands of years. These are no longer adequate to address the challenges of the 21st century, as mines venture to increasingly greater depths. The development of the synthetic rock mass (SRM) in 2008 provides researchers with the ability to analyze the deformational behavior of rock masses that are anisotropic and discontinuous-attributes that were described as the defining characteristics of in situ rock by Leopold Mfiller, the president and founder of the International Society for Rock Mechanics (ISRM), in 1966. Recent developments in the numerical modeling of large-scale mining operations (e.g., caving) using the SRM reveal unanticipated deformational behavior of the rock. The application of massive parallelization and cloud computational techniques offers major opportunities: for example, to assess uncertainties in numerical predictions: to establish the mechanics basis for the empirical rules now used in rock engineering and their validity for the prediction of rock mass behavior beyond current experience: and to use the discrete element method (DEM) in the optimization of deep mine design. For the first time, mining-and rock engineering-will have its own mechanics-based Ulaboratory." This promises to be a major tool in future planning for effective mining at depth. The paper concludes with a discussion of an opportunity to demonstrate the application of DEM and SRM procedures as a laboratory, by back-analysis of mining methods used over the 80-year history of the Mount Lvell Copper Mine in Tasmania.展开更多
The coal resources of Nigeria occur mainly within the Benue Trough which includes the Anambra Basin. In the Lower Benue Trough/Anambra Basin, sub-bituminous coals occur within the Maastrichtian Mamu Formation in Enugu...The coal resources of Nigeria occur mainly within the Benue Trough which includes the Anambra Basin. In the Lower Benue Trough/Anambra Basin, sub-bituminous coals occur within the Maastrichtian Mamu Formation in Enugu (Enugu State), Owukpa (Benue State), Okaba (Kogi State) and Ogboyaga (Kogi State). High-volatile bituminous coals occur within the Turonian-Coniacian Awgu Formation in the Middle Benue Trough around Obi/Lafia (Nasarawa State) with outcrop exposures at Jangwa-Shankodi. Organic petrographic results show that huminites dominate the maceral composition of the Anambra Basin coals and have vitrinite reflectance values that range from 0.40% to 0.63 Ro%. In the coals from the Middle Benue Trough, vitrinite macerals predominate the petrographic composition and Ro values range from 0.81% to 1.25%. Based on the petrographic composition and rank evaluation, the sub-bituminous coals in Enugu, Owukpa, Okaba and Ogboyaga (Anambra Basin) are optimum for combustion and electric power generation and sub-optimum for liquefaction, while the high-volatile bituminous coals in the Obi/Lafia area (Middle Benue Trough), apart from being optimum for liquefaction, are the most suitable as raw material for coke making (carbonization) in steel manufacture and as exploration targets for coal-bed methane gas and liquid hydrocarbons.展开更多
Manghan Faulted Sag is an exploratory target area in Kailu Basin. In order to determine its exploration prospect, the effectiveness of its source rocks is evaluated by organic geochemical behavior analysis of the samp...Manghan Faulted Sag is an exploratory target area in Kailu Basin. In order to determine its exploration prospect, the effectiveness of its source rocks is evaluated by organic geochemical behavior analysis of the samples, and their distributions are predicted using trace integration seismic inversion technology. Studies on their organic matter abundance, type and maturity indicate that the source rocks in the Sag have great generating potentials. Furthermore, it is found that, based on the spatial distribution predication, the source rocks in the Sag are well developed. Therefore, the Sag has a promising prospect for exploration.展开更多
The Assosa region of western Ethiopia hosts newly discovered and potentially highly economic graphite-bearing schist units. Due to its unique physical and chemical properties, graphite is quickly becoming an increasin...The Assosa region of western Ethiopia hosts newly discovered and potentially highly economic graphite-bearing schist units. Due to its unique physical and chemical properties, graphite is quickly becoming an increasingly important economic resource. Graphite occurs over much of the area, and is hosted predominantly by quartz-graphitic schist, quartz-feldspar-mica schist and quartzite. The quartz-graphitic schist covers an area of 37 km2, forming steep valleys and ridges across a 190 km long belt. Graphite is texturally-variable within and across units. Crystal habit varies from highly crystalline to irregular flakes. Flake sizes range from amorphous and crystalline small flake to coarse large flake (〉 150 p.m), with beneficiation of- 70% and yield potential of 〉 95% (froth flotation methods). The license area is already a well-known gold-hosting area, and potentially economic gold deposits occur within the graphite-bearing units. Overall, the site shows excellent geochemical indicators, field observations and historical accounts of high gold content. It is suggested that textural variations may be the product of (1) early in-situ formation during (early- to late-Proterozoic) prograde metamorphism and (2) later vein-type mineralization during retrograde metamorphism. The discovery of graphite in western Ethiopia is the first documented and preliminary studies suggest a high economic potential for the deposits.展开更多
The main achievements in the development of hardly-recoverable resources are currently associated with shale oil and gas. The result of the "shale revolution" was billions of dollars in losses for oil exporters. The...The main achievements in the development of hardly-recoverable resources are currently associated with shale oil and gas. The result of the "shale revolution" was billions of dollars in losses for oil exporters. The question is how this situation w'ill be long-lasting or "shale bubble" will burst. The success of the shale revolution can be not only an economic win or economic defeat of the United States, the question is about reputation as a global political leader and the country's ability to solve the most difficult technological problems. Everything at stake to extend the "shale gas revolution" as it is possible longer, in time to prepare the conditions and technologies for a new energy revolution and to maintain the usual high level of energy consumption. The situation is further complicated by the introduction in the game of OPEC (organization of petroleum exporting countries) causing oil prices dropped below the cost of shale oil. The future of high technology in the production of oil depends on whether exporters and importers to negotiate the best price for oil, to ensure the sustainable development of the world economy.展开更多
Since the discovery of the Tahe oilfield, it has been controversial on whether the main source rock is in the Cambrian or Middle-Upper Ordovician strata. In this paper, it is assumed that the crude oil from the Wells ...Since the discovery of the Tahe oilfield, it has been controversial on whether the main source rock is in the Cambrian or Middle-Upper Ordovician strata. In this paper, it is assumed that the crude oil from the Wells YM 2 and TD 2 was derived from the Middle-Upper Ordovician and Cambrian source rocks, respectively. We analyzed the biomarkers of the crude oil, asphalt-adsorbed hydrocarbon and saturated hydrocarbon in bitumen inclusions from the Lunnan and Hade areas in the North Uplift of the Tarim Basin. Results show that the ratios of tricyclic terpane C2~/C23 in the crude oil, asphalt-adsorbed hydrocarbon and saturated hydrocarbon in bitumen inclusions are less than 1.0, indicating that they might be from Upper Ordovician source rocks; the ratios of C28/(C27+C28+C29) steranes in the saturated hydrocarbon from reservoir bitumen and bitumen inclusions are higher than 25, suggesting that they might come from the Cambrian source rocks, however, the ratios of C28/(C27+C28+C29) steranes in oil from the North Uplift are less than 25, suggesting that they might be sourced from the Upper Ordovician source rocks. These findings demonstrate that the sources of crude oil in the Tarim Basin are complicated. The chemical composition and carbon isotopes of Ordovician reservoired oil in the Tarim Basin indicated that the crude oil in the North Uplift (including the Tahe oilfield) and Tazhong Depression was within mixture areas of crude oil from the Wells YM 2 and TD 2 as the end members of the Cambrian and Middle-Upper Ordovician sourced oils, respectively. This observation suggests that the crude oil in the Ordovician strata is a mixture of oils from the Cambrian and Ordovician source rocks, with increasing contribution from the Cambrian source rocks from the southern slope of the North Uplift to northern slope of the Central Uplift of the Tarim Basin. Considering the lithology and sedimentary facies data, the spatial distribution of the Cambrian, Middle-Lower Ordovician and Upper Ordovician source rocks was reconstructed on the basis of seismic reflection characteristics, and high-quality source rocks were revealed to be mainly located in the slope belt of the basin and were longitudinally developed over the maximum flooding surface during the progressive-regressive cycle. Affected by the transformation of the tectonic framework in the basin, the overlays of source rocks in different regions are different and the distribution of oil and gas was determined by the initial basin sedimentary structure and later reformation process. The northern slope of the Central Uplift-Shuntuo-Gucheng areas would be a recent important target for oil and gas exploration, since they have been near the slope area for a long time.展开更多
文摘An increased global supply of minerals is essential to meet the needs and expectations of a rapidly rising world population. This implies extraction from greater depths. Autonomous mining systems, developed through sustained R&D by equipment suppliers, reduce miner exposure to hostile work environments and increase safety. This places increased focus on "ground control" and on rock mechanics to define the depth to which minerals may be extracted economically. Although significant efforts have been made since the end of World War II to apply mechanics to mine design, there have been both technological and organizational obstacles. Rock in situ is a more complex engineering material than is typically encountered in most other engineering disciplines. Mining engineering has relied heavily on empirical procedures in design for thousands of years. These are no longer adequate to address the challenges of the 21st century, as mines venture to increasingly greater depths. The development of the synthetic rock mass (SRM) in 2008 provides researchers with the ability to analyze the deformational behavior of rock masses that are anisotropic and discontinuous-attributes that were described as the defining characteristics of in situ rock by Leopold Mfiller, the president and founder of the International Society for Rock Mechanics (ISRM), in 1966. Recent developments in the numerical modeling of large-scale mining operations (e.g., caving) using the SRM reveal unanticipated deformational behavior of the rock. The application of massive parallelization and cloud computational techniques offers major opportunities: for example, to assess uncertainties in numerical predictions: to establish the mechanics basis for the empirical rules now used in rock engineering and their validity for the prediction of rock mass behavior beyond current experience: and to use the discrete element method (DEM) in the optimization of deep mine design. For the first time, mining-and rock engineering-will have its own mechanics-based Ulaboratory." This promises to be a major tool in future planning for effective mining at depth. The paper concludes with a discussion of an opportunity to demonstrate the application of DEM and SRM procedures as a laboratory, by back-analysis of mining methods used over the 80-year history of the Mount Lvell Copper Mine in Tasmania.
文摘The coal resources of Nigeria occur mainly within the Benue Trough which includes the Anambra Basin. In the Lower Benue Trough/Anambra Basin, sub-bituminous coals occur within the Maastrichtian Mamu Formation in Enugu (Enugu State), Owukpa (Benue State), Okaba (Kogi State) and Ogboyaga (Kogi State). High-volatile bituminous coals occur within the Turonian-Coniacian Awgu Formation in the Middle Benue Trough around Obi/Lafia (Nasarawa State) with outcrop exposures at Jangwa-Shankodi. Organic petrographic results show that huminites dominate the maceral composition of the Anambra Basin coals and have vitrinite reflectance values that range from 0.40% to 0.63 Ro%. In the coals from the Middle Benue Trough, vitrinite macerals predominate the petrographic composition and Ro values range from 0.81% to 1.25%. Based on the petrographic composition and rank evaluation, the sub-bituminous coals in Enugu, Owukpa, Okaba and Ogboyaga (Anambra Basin) are optimum for combustion and electric power generation and sub-optimum for liquefaction, while the high-volatile bituminous coals in the Obi/Lafia area (Middle Benue Trough), apart from being optimum for liquefaction, are the most suitable as raw material for coke making (carbonization) in steel manufacture and as exploration targets for coal-bed methane gas and liquid hydrocarbons.
基金Project (No. 40238059) supported by the National Natural Science Foundation of China
文摘Manghan Faulted Sag is an exploratory target area in Kailu Basin. In order to determine its exploration prospect, the effectiveness of its source rocks is evaluated by organic geochemical behavior analysis of the samples, and their distributions are predicted using trace integration seismic inversion technology. Studies on their organic matter abundance, type and maturity indicate that the source rocks in the Sag have great generating potentials. Furthermore, it is found that, based on the spatial distribution predication, the source rocks in the Sag are well developed. Therefore, the Sag has a promising prospect for exploration.
文摘The Assosa region of western Ethiopia hosts newly discovered and potentially highly economic graphite-bearing schist units. Due to its unique physical and chemical properties, graphite is quickly becoming an increasingly important economic resource. Graphite occurs over much of the area, and is hosted predominantly by quartz-graphitic schist, quartz-feldspar-mica schist and quartzite. The quartz-graphitic schist covers an area of 37 km2, forming steep valleys and ridges across a 190 km long belt. Graphite is texturally-variable within and across units. Crystal habit varies from highly crystalline to irregular flakes. Flake sizes range from amorphous and crystalline small flake to coarse large flake (〉 150 p.m), with beneficiation of- 70% and yield potential of 〉 95% (froth flotation methods). The license area is already a well-known gold-hosting area, and potentially economic gold deposits occur within the graphite-bearing units. Overall, the site shows excellent geochemical indicators, field observations and historical accounts of high gold content. It is suggested that textural variations may be the product of (1) early in-situ formation during (early- to late-Proterozoic) prograde metamorphism and (2) later vein-type mineralization during retrograde metamorphism. The discovery of graphite in western Ethiopia is the first documented and preliminary studies suggest a high economic potential for the deposits.
文摘The main achievements in the development of hardly-recoverable resources are currently associated with shale oil and gas. The result of the "shale revolution" was billions of dollars in losses for oil exporters. The question is how this situation w'ill be long-lasting or "shale bubble" will burst. The success of the shale revolution can be not only an economic win or economic defeat of the United States, the question is about reputation as a global political leader and the country's ability to solve the most difficult technological problems. Everything at stake to extend the "shale gas revolution" as it is possible longer, in time to prepare the conditions and technologies for a new energy revolution and to maintain the usual high level of energy consumption. The situation is further complicated by the introduction in the game of OPEC (organization of petroleum exporting countries) causing oil prices dropped below the cost of shale oil. The future of high technology in the production of oil depends on whether exporters and importers to negotiate the best price for oil, to ensure the sustainable development of the world economy.
基金supported by the National Natural Science Foundation of China(Grant Nos.41230312,41322016,41625009)the Key Project of China National Program for Fundamental Research and Development(Grant No. 2012CB214800)
文摘Since the discovery of the Tahe oilfield, it has been controversial on whether the main source rock is in the Cambrian or Middle-Upper Ordovician strata. In this paper, it is assumed that the crude oil from the Wells YM 2 and TD 2 was derived from the Middle-Upper Ordovician and Cambrian source rocks, respectively. We analyzed the biomarkers of the crude oil, asphalt-adsorbed hydrocarbon and saturated hydrocarbon in bitumen inclusions from the Lunnan and Hade areas in the North Uplift of the Tarim Basin. Results show that the ratios of tricyclic terpane C2~/C23 in the crude oil, asphalt-adsorbed hydrocarbon and saturated hydrocarbon in bitumen inclusions are less than 1.0, indicating that they might be from Upper Ordovician source rocks; the ratios of C28/(C27+C28+C29) steranes in the saturated hydrocarbon from reservoir bitumen and bitumen inclusions are higher than 25, suggesting that they might come from the Cambrian source rocks, however, the ratios of C28/(C27+C28+C29) steranes in oil from the North Uplift are less than 25, suggesting that they might be sourced from the Upper Ordovician source rocks. These findings demonstrate that the sources of crude oil in the Tarim Basin are complicated. The chemical composition and carbon isotopes of Ordovician reservoired oil in the Tarim Basin indicated that the crude oil in the North Uplift (including the Tahe oilfield) and Tazhong Depression was within mixture areas of crude oil from the Wells YM 2 and TD 2 as the end members of the Cambrian and Middle-Upper Ordovician sourced oils, respectively. This observation suggests that the crude oil in the Ordovician strata is a mixture of oils from the Cambrian and Ordovician source rocks, with increasing contribution from the Cambrian source rocks from the southern slope of the North Uplift to northern slope of the Central Uplift of the Tarim Basin. Considering the lithology and sedimentary facies data, the spatial distribution of the Cambrian, Middle-Lower Ordovician and Upper Ordovician source rocks was reconstructed on the basis of seismic reflection characteristics, and high-quality source rocks were revealed to be mainly located in the slope belt of the basin and were longitudinally developed over the maximum flooding surface during the progressive-regressive cycle. Affected by the transformation of the tectonic framework in the basin, the overlays of source rocks in different regions are different and the distribution of oil and gas was determined by the initial basin sedimentary structure and later reformation process. The northern slope of the Central Uplift-Shuntuo-Gucheng areas would be a recent important target for oil and gas exploration, since they have been near the slope area for a long time.