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Machine learning (ML) is increasingly being leveraged by the mining industry to understand how rock properties vary at a mine site. In previously published work, the rock type, granodiorite, was predicted with high accuracy by the random forest (RF) ML method at the Erdenet copper mine in Mongolia. As a result of the optimistic results (86% overall success rate), this paper extended the research to determine if ML would be successful in modeling rock domains. Rock domains are groups of rocks that occur together. There were two additional goals. One was to determine if the variograms could predict or help understand how ML methods would perform on the data. The second was to determine if 2D modeling would perform well given the disseminated nature of the deposit. ML methods, multilayer perceptron (MLP), k-nearest neighborhood (KNN) and RF, were applied to model six rock domains, D0–D5, in 2D and 3D. Modeling performance was poor in 2D. Prediction performance accuracy was high in 3D for the domains D1 (92–94%), D2 (94–96%) and D4 (85–98%). Note that the domains D1 and D2 together constituted about 80% of the samples. Conclusions drawn in this paper are based on the results of 3D modeling since 2D modeling performance was poor. Prediction performance appeared to depend on two factors. It was better for a domain when the domain was not a minuscule proportion of the sample. It was also better for domains whose indicator semi-variogram (ISV) range was high. For example, though D4 only contributed 15% of the samples, the range was high. MLP did not perform as well as KNN and RF, with RF performing the best. The hyperparameters of KNN and RF suggested that performance was best when only a small number of samples were used to make a prediction. One overall summary conclusion is that the two most important domains, D1 and D2, could be predicted with high accuracy using ML. The second summary conclusion is that semi-variograms can provide insight into ML performance. [ABSTRACT FROM AUTHOR]

The gabbro quarry at Szarvaskő Tardos is located in the western part of Bükk Mountain, part of the North Central Mountains, in the valley of the Eger stream, 2.5 km from Szarvaskő village. The rock material of the quarry was known earlier as Western Bükk diabase, however, according to the current nomenclature the gabbro is referred as Tardos Gabbro Formation and Szarvaskő Basalt Formation. The basic magmatic rock formations are results of the undersea magmatic activity during the Jurassic period, Callovian stage. The total length of the pit wall in the gabbro quarry at Szarvaskő Tardos is 679 m in two mining operations levels. Volume of gabbro blocks is generally between 0.5-1.0 m3, sometimes 2-3 m3, and occasionally 8-10 m3. The gabbro is dark grey in colour with greenish shade, dense, grained, hard and brittle fracturing. The paper describes the exploratory mining geology research of the quarry, the mineral composition of the gabbro together with its physical properties and utilization possibilities. The high quality gabbro of the quarry was utilized as crushed stone products for road construction and as construction blocks. The paper calls the attention to the need of more detailed, complex exploratory mining geology research for future utilization. [ABSTRACT FROM AUTHOR]

With depleted coal resources or deteriorating mining geological conditions, some coal mines have been abandoned in the Fengfeng mining district, China. Water that accumulates in an abandoned underground mine (goaf water) may be a hazard to neighboring mines and impact the groundwater environment. Groundwater samples at three abandoned mines (Yi, Er and Quantou mines) in the Fengfeng mining district and the underlying Ordovician limestone aquifer were collected to characterize their chemical and isotopic compositions and identify the sources of the mine water. The water was HCO3·SO4-Ca·Mg type in Er mine and the auxiliary shaft of Yi mine, and HCO3·SO4-Na type in the main shaft of Quantou mine. The isotopic compositions (δD and δ18O) of water in the three abandoned mines were close to that of Ordovician limestone groundwater. Faults in the abandoned mines were developmental, possibly facilitating inflows of groundwater from the underlying Ordovician limestone aquifers into the coal mines. Although the Sr2+ concentrations differed considerably, the ratios of Sr2+/Ca2+ and 87Sr/86Sr and the 34S content of SO42− were similar for all three mine waters and Ordovician limestone groundwater, indicating that a close hydraulic connection may exist. Geochemical and isotopic indicators suggest that (1) the mine waters may originate mainly from the Ordovician limestone groundwater inflows, and (2) the upward hydraulic gradient in the limestone aquifer may prevent its contamination by the overlying abandoned mine water. The results of this study could be useful for water resources management in this area and other similar mining areas. [ABSTRACT FROM AUTHOR]

Advances in tracking technology enable the gathering of spatio-temporal data in the form of trajectories, which when analysed can convey useful knowledge. In particular, discovering groups of moving objects is a valuable means for a wide class of problems related to mobility. The task of group mining has been investigated by considering mostly the spatial closeness and similarity of the trajectories, while little attention has been paid to the relationships between the trajectories and time-changing nature of the trajectories. The relationships may provide evidence of interactions between the moving objects. The time-changing nature may provide evidence of dynamics of the movements. Therefore, interactions and dynamics can be sources of information to be considered in order to discover new forms of groups.  Motivated by this, we introduce the concept of crews and propose a method to discover crews. A crew gathers moving objects with similar interactions and similar dynamics. The proposed method relies on i) new movement parameters, which explicitly consider interactions and dynamics, and ii) a distance-free clustering algorithm, which groups objects based on the similarity of the movement parameters. We conduct extensive experiments, which include a quantitative evaluation of the quality of the crews and comparison with alternative solutions. [ABSTRACT FROM AUTHOR]

This paper presents all the rock mechanics studies carried out at an underground metal mine in Kadapa, Andhra Pradesh. The rock mechanics investigations in this mine include optimization of pillar dimensions by numerical modelling, the feasibility of hangwall lode mining at shallow depth, support design for deeper levels, instrumentation to monitor the strata for an experimental hangwall stope. The main aim is to improve extraction ratio and the mine safety levels from these rock mechanics studies to develop a mine. The effect on the linear advance in both footwall lode and hangwall lode is studied, monitored and found that there is almost 25% increase in total cost per round of blast due to difficult geo-mining conditions and affecting total cost per tonne of ore extracted from hangwall in contrast to footwall lode development and safety aspects. A critical case study with techno-economic cost analysis in view of their geo-mining conditions has been discussed. [ABSTRACT FROM AUTHOR]

With increasing coal mining intensity, the number, length and depth of coal mine roadways is increasing drastically, the traditional drill-&-blast method and comprehensive mechanized driving method, and corresponding support methods are incapable of controlling the surrounding rock stability gradually. Hard rock TBMs (Full-face tunnel boring machine) have significant advantages in terms of fast advance rates, high support capacity, being favorable to environmental protection and low construction costs. Meanwhile some modern mines are possible target for TBM application. TBMs have been successfully used for some roadway and inclined shaft construction. Therefore, it can be foreseeable that the TBM tunnelling method will be the first choice and preferred future method for deep rock roadway construction in coal mines. However, because of the complicated construction environments, many technical challenges are encountered during TBM tunnelling in deep roadway including the presence of: (a) mixed and changing grounds; (b) high geostress; (c) squeezing deformation and the induced TBM entrapment or overstressing on supports; (d) fractured and faulted zones; (e) special requirements for TBM assembly, explosion-proof, influences of roadway or cavern groups, drainage due to the construction environments in coal mine. Therefore, in order to cope with these challenges in deep roadway tunnelling, the following scientific problems are identified as needing urgent examination: ground stress distribution and geological conditions investigation of deep roadway; interaction mechanism between the surrounding rock and the TBM; safety control for surrounding rock stability; informatization construction, optimization decision and intelligent control for TBM tunnelling. Some research progresses are also presented. Solution to these problems will provide an important theoretical foundation for application of TBMs in deep coal mines. [ABSTRACT FROM AUTHOR]

Infrared field-based reflectance spectroscopy in the Visible - Near-Infrared - Short-wave Infrared (VIS-NIR-SWIR) domain is a useful tool in mining geology particularly efficient for investigating the clay mineralogy of alteration haloes around ore deposits. It is used as a routine technique for the basic identification, mapping and semi-quantification of clay mineral species. However, the use of this technique for prospecting in hypogene deposits at depth in intertropical areas is strongly limited because of the presence of a thick, kaolinite-rich lateritic cover. Due to the strong IR absorption of kaolinite and the overlapping of its IR bands with those of most of the phyllosilicates in the SWIR domain, the use of field based near-infrared spectroscopy does not permit efficient identification and mapping of the phyllosilicates inherited from hypogene alteration that persist in the saprolite of lateritic profiles. In this paper, we propose a methodology to enhance the detection and semi-quantification of hypogene phyllosilicate minerals in kaolinite-rich lateritic saprolites using calibration curves. Those curves are built from the NIR spectra of binary admixtures of kaolinite or smectite with muscovite, Fe-Mg chlorite, clinochlore or talc in different known proportions. For each admixture series, calibration curves were established, based on investigation of two regions of interest within the NIR domain (1350–1470 nm and 2080–2500 nm) using a field-based spectrometer. For each binary mixture series of phyllosilicates, the second derivative of the NIR spectra was used to enhance the detection of the diagnostic absorption bands of each type of phyllosilicate, and hence to optimize the calculation of the intensity ratios between the diagnostic bands of the phyllosilicate components as a function of their percentage in the mixture. In presence of large amounts of lateritic kaolinite, the detection limit of the major types of hypogene phyllosilicates has been found at ranges from 5 to 10 wt% of the total clay content using the second derivative of the NIR spectra acquired with a field-based spectrometer. Above these aforementioned limits of detection, the semi-quantitative data obtained by comparing the NIR reflectance spectra of natural samples with those of the calibration curves could permit to map hypogene alteration haloes directly from the lateritic saprolite. Finally the described approach has been successfully tested on natural samples from the skarn deposits of the Ity gold mine (Ivory Coast). [ABSTRACT FROM AUTHOR]

Consumption of unsafe food is one of the most important public health concerns. Trace elements’ contamination caused by direct or indirect activities of mining industries is of importance in this respect. The present study was conducted to assess the chronic dietary exposure and related health risks of trace elements through the intake of selected vegetables and fruits grown under the impact of mining industry in Syunik region (Armenia). Consumption data were obtained via food frequency questionnaire and the concentrations of Cu, Mo, Ni, Cr, Pb, Zn, Hg, and Cd in different fruits and vegetables were determined. Moreover, by combining concentration data with consumption data, estimated daily intake, and target hazard quotient were assessed for each element. The results obtained showed that mean concentrations for Pb and Hg in some vegetables exceeded maximum acceptable levels set by international organizations. Hazard indexes > 1 have been obtained in some cases indicating that for some vegetables (particularly for potato, carrot, maize, onion leaf, grape, bean, beet, sweet pepper, eggplant, and tomato) habitual consumption has a potential to pose adverse health effect to the local population. [ABSTRACT FROM PUBLISHER]

Under high horizontal ground stress, the squeezing failure has been a common failure pattern for deep roadway. And the large deformation of surrounding rock mass around the roadway has also been a major challenge for deep mining practices. This paper describes a case study of the failure mechanisms and stability control technology of deep roadway under high horizontal ground stress in Jinchuan mine in Gansu Province, China. And this paper also aims to propose a kind of support strategy to prevent the plastic slippage around the floor of roadway. This study started with an in situ broken zone measurement programme to determine the depth of broken zone at each part of the roadway. Combined with long bolt and floor beam, an improved support strategy has been proposed. The field test results show that the improved support strategy can successfully solve the problems of side wall collapse and floor heaven. It can significantly restricts rock mass large deformation and avoid frequent repair. Compare to the original support, the improved support strategy can greatly save investment of mines and also has good application value. [ABSTRACT FROM AUTHOR]

This study investigates the effect of key stratum on the mining abutment pressure of a coal seam. Firstly, a total of 42 configurations with different key stratum thicknesses and heights have been numerically simulated by the Universal Distinct Element Code (UDEC) software. Then, through the analysis of two sets of parameters derived from the simulation results, the peak abutment pressure and the range of influence, shows that the effect of key stratum on the abutment pressure is conditional. For a relatively small key stratum thickness, less than 159 m, the effect on the abutment pressure is negligible unless the key stratum height is higher than the critical height of 421 m. On the other hand, for the key stratum thickness bigger than 159 m, the abutment pressure is affected irrespective of the key stratum height. Finally, in order to verify the simulation results, the abutment pressure of a field model has been analyzed. The analysis shows that the abutment pressure of the field model with a key stratum is 42% higher than that of the model without any key stratum. The stress at the field model has increased from the virgin stress of 14.6 MPa to the stress of 21.5 MPa. Meanwhile, the stress concentration coefficient has changed from 1 to 1.5, which caused the coal and gas burst disaster. The results of this study can be very useful to explain the reason for the occurrence of some dynamic disasters affected by the key stratum. [ABSTRACT FROM AUTHOR]

Recent developments in modelling and optimization approaches for the production of mineral and energy resources have resulted in new simultaneous stochastic optimization frameworks and related digital technologies. A mining complex is a type of value chain whereby raw materials (minerals) extracted from various mineral deposits are transformed into a set of sellable products, using the available processing streams. The supply of materials extracted from a group of mines represents a major source of uncertainty in mining operations and mineral value chains. The simultaneous stochastic optimization of mining complexes, presented herein, aims to address major limitations of past approaches by modelling and optimizing several interrelated aspects of the mineral value chain in a single model. This single optimization model integrates material extraction from a set of sources along with their uncertainty, the related risk management, blending, stockpiling, non-linear transformations that occur in the available processing streams, the utilization of processing streams, and, finally, the transportation of products to customers. Uncertainty in materials extracted from the related mineral deposits of a mining complex is represented by a group of stochastic simulations. This paper presents a two-stage stochastic mixed integer nonlinear programming formulation for modelling and optimizing a mining complex, along with a metaheuristic-based solver that facilitates the practical optimization of exceptionally large mathematical formulations. The distinct advantages of the approach presented herein are demonstrated through two case studies, where the stochastic framework is compared to past approaches that ignore uncertainty. Results demonstrate major improvements in both meeting forecasted production targets and net present value. Concepts and methods presented in this paper for the simultaneous stochastic optimization for mining complexes may be adopted and applied to the optimization of smart oil fields. [ABSTRACT FROM AUTHOR]

Mining activities seriously interfere with the regional land use, which lead to a strong influence in ecosystem. After collecting many studies related to ecosystem service values (ESVs) in resource-based cities in China, this paper extracts a series of variables with Meta-analysis to establish benefit transfer models for assessing ESVs of cultivated land, forest land, grassland and waters especially in mining cities, then examines the feasibility of these models in Wu’an City to evaluate the ESVs of Wu’an in 1987, 2001 and 2014. The results show that: 1) the benefit transfer method can effectively assess the ESVs in mining cities; 2) there is a declining trend after the increase in the total ESVs of Wu’an, and a significant decrease occurred after 2001; 3) from the aspect of land area, the degree that the mining activities interfere with the land use type is cultivated land>grassland>waters>forest land from 1987 to 2014; from the aspect of the ESVs, the degree that the mining activities interfere with the land use type is cultivated land>waters>grassland>forest land; and 4) when the total area of ecological land reduces, a reasonable optimization of ecological land structure can improve the total ESVs rather. [ABSTRACT FROM AUTHOR]

Books and DVDs are still being sold, and websites claim, that a boat-shaped structure in the Dogubayazit area of eastern Turkey is what remains of Noah's ark. The formation is described as being composed of petrified wood, with iron washers, rivets, and brackets that held the ark walls together, and anchor stones that served to stabilize the ark. While remains of Noah's ark could conceivably be found at another site, more careful examination of this particular formation shows that (a) the "petrified wood" is actually basalt; (b) the supposed iron washers, rivets, and brackets are cemented grains of magnetite containing manganese and titanium; and (c) the stones labeled as "anchors" naturally occur in the area. Initial findings to this effect were noted by this author in the Journal of Geosciences Education 44 (1996): 439-44. Considering ongoing claims for the Dogubayazit formation, this article more thoroughly describes the geology with additional argument, figures, and information. [ABSTRACT FROM AUTHOR]

Mining accidents are sometimes preceded by high levels of crackling noise, which follow universal rules for the collapse of minerals. The archetypal test cases are sandstone and coal. Their collapse mechanism is almost identical to earthquakes: the crackling noise in large, porous samples follows a power law (Gutenberg-Richter) distribution P ~ E-ɛ with energy exponents ɛ for near critical stresses of ɛ = 1.55 for dry and wet sandstone, and ɛ = 1.32 for coal. The exponents of early stages are slightly increased, 1.7 (sandstone) and 1.5 (coal), and appear to represent the collapse of isolated, uncorrelated cavities. A significant increase of the acoustic emission, AE, activity was observed close to the final failure event, which acts as 'warning signal' for the impending major collapse. Waiting times between events also follow power law distributions with exponents 2+ξ between 2 and 2.4. Aftershocks occur with probabilities described by Omori coefficients ρ between 0.84 (sandstone) and 1 (coal). The 'Båth's law' predicts that the ratio between the magnitude of the main event and the largest aftershock is 1.2. Our experimental findings confirm this conjecture. Our results imply that acoustic warning methods are often possible within the context of mining safety measures, although it is not only the increase of crackling noise that can be used as early warning signal but also the change of the energy distribution of the crackling events. [ABSTRACT FROM AUTHOR]

The Gánt felsőlegelő dolomite quarry is located in the South-East edge of the Vértes, on the North- East side of the No. 8123 highway, at about 3 km distance from Gánt village. The total length of the pit wall in the Gánt felsőlegelő dolomite quarry is 4590 m. As a result of the mining activity, the dolomite has been explored in vertical direction at 46 meters. The diploporic dolomite is generally light or pale grey in colour, dense, hard and locally fragmented due to tectonic activity. At certain locations, light red and brown discoloration is observed by limonite formation that is the result of the precipitation from iron contaminated solutions filtrating through crevices. Mining geology observations confirmed the thickness of dolomite benches in the range of several cm to several m. Blocks are also observed in the extracted dolomite bulk. Volume of blocks is generally between 0.5-1.0 m3, sometimes 2-5 m3. The largest block ever observed had the volume of 18 m3. Shape of blocks is irregular, fragmented, eventually crumbled. The high quality dolomite products of the quarry can be utilized as crushed stone products for road construction (road base), as aggregate for concrete and - due to its frost resistance - as construction blocks. The dolomite/clay products can be used for embankments or in recultivation. The rich dolomite resources at the Gánt felsőlegelő dolomite quarry can provide high quality products for the region for a long time. [ABSTRACT FROM AUTHOR]

Over the last 30 years the average grade of ore bodies has significantly decreased while the proportion of waste removal has in many cases more than doubled. This in turn has led to a major increase in energy consumption and decrease in productivity across mining operations. Metal preconcentration at coarse scale (10–100 mm) by screening has the potential to reverse decreasing mining productivity trends through early rejection of uneconomic grade material prior to energy intensive comminution. Metal preconcentration of feed grades using screening exploits the propensity of certain ores to preferentially deport metal into specific size fractions during breakage. This phenomenon is referred as preferential grade by size deportment. The exploitation of preferential grade by size response involves generation of multiple streams with different metal content post screening. Streams can be engineered for different grade characteristics suitable for different processing destination (eg: as waste, leach, and mill). Preferential grade by size data obtained by an extensive belt cut sampling campaign after primary crushing has been used to develop a method to define samples that are amenable for metal preconcentration by size. This amenability changes depending on cut-off grade, magnitude of preferential grade by size response and the proportion of mass contained in individual screen products. Outcomes of this work will support the short term preferential grade by size operational implementation. [ABSTRACT FROM AUTHOR]

The hereby paper emphasizes the importance and development of non-metallic substances mining in Romania, including available non-metallic deposits, implemented and possible future exploitation methods as well as maximal production amounts to be reached in the case exploitation is resumed. [ABSTRACT FROM AUTHOR]

Archaeological excavations on the 'Kiechlberg' near Thaur (Tyrol, Austria) excavated a dwelling site with an experimental phase of copper metallurgy from the Late Neolithic to the Early Bronze Age. Findings of copper ore, slag, unwrought copper and ingots document the processing sequence from ore to raw copper. Archaeobotanical studies on soil samples from these cultural layers reveal that the early dwellers were embedded in an agricultural society with cultivation of Hordeum vulgare (barley), Triticum dicoccon (emmer) and Pisum sativum (pea). Small domestic animals like Ovis/ Capra (sheep/goats) dominate during the Late/Final Neolithic whereas Bos sp. (cattle) prevail during the Early Bronze Age. Nutrition was supplemented by gathering wild plants, e.g. Corylus avellana (hazelnuts) and Quercus sp. (acorns). Anthracological analyses provide information about the use of wood which was primarily taken from a mixed conifer forest composed of Picea abies (spruce), Abies alba (fir) and some Fagus sylvatica (beech). The surrounding woodland was only moderately affected by exploitation for construction and energy purposes even in epochs when smelting activities took place. [ABSTRACT FROM AUTHOR]

[Display omitted] • Conceptual model of abandoned underground mine is introduced. • Abandoned underground mine is vulnerable and fragile with time-limited stability. • Its environment is azonal and fast evolving. • Abandoned underground mine is an important semi-natural ecosystem. We have investigated a typical abandoned underground slate mine situated in the Bohemian Massif (Central Europe) in order to describe its elementary components and to outline the varied relations among them. Based on the results from geological, geomorphological, hydrological, microclimatic, and biological investigation, we have defined the abandoned underground mine as an important but overlooked semi-natural ecosystem that represents an azonal and relatively fast evolving environment. Unlike any other studies published so far, we have found it also vulnerable in terms of fragility and time-limited stability. Our results together with a comprehensive discussion highlight the fundamental features of the abandoned underground mine and finally serve as a basis on which we introduce a conceptual model of the abandoned underground mine. The complex and interdisciplinary perception of abandoned underground mines is crucial for appropriate environmental assessment, tourist management, natural protection or remediation. [ABSTRACT FROM AUTHOR]

In this work, the analysis of TerraSAR-X satellite images combining both conventional and advanced Differential Synthetic Aperture Radar Interferometry (DInSAR) approaches has proven to be effective to detect and monitor fast evolving mining subsidence on urban areas in the Upper Silesian Coal Basin (Poland). This region accounts for almost three million inhabitants where mining subsidence has produced severe damage to urban structures and infrastructures in recent years. Conventional DInSAR approach was used to generate 28 differential interferograms between 5 July 2011 and 21 June 2012 identifying 31 subsidence troughs that account up to 245 mm of displacement in 54 days (equivalent to 1660 mm/year). SqueeSARTM processing yielded a very dense measurement point distribution, failing to detect faster displacements than 330 mm/year, which occur within the subsidence troughs detected with conventional DInSAR. Despite this limitation, this approach was useful to delimit stable areas where mining activities are not conducted and areas affected by residual subsidence surrounding the detected subsidence troughs. These residual subsidence mining areas are located approximately 1 km away from the 31 detected subsidence troughs and account for a subsidence rate greater than 17 mm/year on average. The validation of this methodology has been performed over Bytom City were underground mining activity produced severe damages in August 2011. Conventional DInSAR permitted to successfully map subsidence troughs between July and August 2011 that coincide spatially and temporally with the evolution of underground mining excavations, as well as with the demolition of 28 buildings of Karb district. Additionally, SqueeSARTM displacement estimates were useful to delimit an area of 8.3 km2 of Bytom city that is affected by a residual mining subsidence greater than 5 mm/year and could potentially suffer damages in the midterm. The comparison between geodetic data and SqueeSARTM for the common monitoring period yields and average absolute difference of 7 mm/year, which represents 14% of the average displacement rate measured by the geodetic benchmarks. These results demonstrate that the combined exploitation of high-resolution satellite SAR data through both conventional and advanced DInSAR techniques could be crucial to monitor fast evolving mining subsidence, which may severely impact highly populated mining areas such as the Upper Silesia Coal Basin (USCB). [ABSTRACT FROM AUTHOR]

The current article will attempt to confirm that Polish post-mining areas are characterized by high cognitive and aesthetic values and that they have great geotourism potential, which has been little used so far. Tourism is regarded to be one of the most dynamically growing sectors of the global economy and is a phenomenon that occurs in the landscapes of all ecological and altitudinal zones. Geotourism is among the relatively recent types of tourism. Poland is a highly attractive country for geotourism. The aim of this article is to analyze the distribution and size of post-mining areas in Poland and, based on these analyses, to assess the geotourist potential of selected post-mining regions. Based on the distribution of natural resource mining sites and their potential and actual use in geotourism, the authors selected 20 actual and potential geotourist regions in Poland. These regions were divided into three basic categories based on their attractiveness. [ABSTRACT FROM AUTHOR]

In a mine, knowledge of rock types is often desired as they are important indicators of grade, mineral processing complications, or geotechnical attributes. It is common to model the rock types with visual graphics tools using geologist-generated rock type information in exploration drillhole databases. Instead of this manual approach, this paper used random forest (RF), a machine learning (ML) algorithm, to model the rock type at Erdenet Copper Mine, Mongolia. Exploration drillhole data was used to develop the RF models and predict the rock type based on the coordinates of locations. Data selection and model evaluation methods were designed to ensure applicability for real life scenarios. In the scenario where rock type is predicted close to locations where information is available (such as in blocks being blasted), RF did very well with an overall success rate (OSR) of 89%. In the scenario where rock type was predicted for two future benches (i.e., 30 m below known locations), the best OSR was 86%. When an exploration program was simulated, performance was poor with a OSR of 59%. The results indicate that EMC can leverage RF models for short-term and long-term planning by predicting rock types within drilling blocks or future blocks quite accurately. [ABSTRACT FROM AUTHOR]

8 models corresponding to different coalbed structure were built on the actual drilling data of a mining area from Wolonghu Coal Mine. By using the method of synthetic seismogram, all synthetic seismograms of above models were achieved. And by using the technique of seismic attribute, the attributes of peak amplitude, trough amplitude, instantaneous amplitude, instantaneous frequency and sweetness were extracted from No. 10 coal reflections of above models. On this basis,the technique of crossplot analysis was used to study the distribution pattern of attribute crossplot points of normal coalbed and magmatic intrusion zone. Then the Monte Carlo simulation was used to simulate new attribute crossplots which closer to actual conditions. After analyzed the simulated attribute crossplots, a quantitative standard of interpreting normal coalbed and magmatic intrusion area was given. After applied this standard on actual data of mining area, the predicted boundaries between normal coalbed and coked area and between coked zone and magmatic intrusion area are fully complied with the validation of drilling and underground mining, and the smallest horizontal error is less than 10 m. [ABSTRACT FROM AUTHOR]

This paper probed into the whole height bench cast blasting process and described the influence factors from 3 major perspectives; natural geological, blasting scheming and factitious ones, and selected the throwing rate which was generally accepted in the cast blasting field to assess the blasting performance. Then a novel GA-SVM model was constructed to analyze the real collected explosion data from open pit mining, and verified in a certain open-pit. Also the MIV method was employed to analyze the influence factor at each input factor. The study indicate that; (T) the presented GA-SVM model performs more robust and accurate than other artificial intelligence models such as BP, RBF, GRNN and GA-BP, which has a more stable prediction accuracy of 83.75%. Moreover, due to the ubiquitous paradigm of the presented approach, it provides a single, unified approach to evaluating other blasting performance factors such as the longest thrown distance and loose coefficient etc; (2) for this certain open pit which maintains a steady lithological character and design parameters, the bench height, explosive specific charge possess a positive correlation coefficient with the throwing rate, while line of least resistance, the slope angle and the profile width perform the opposite. [ABSTRACT FROM AUTHOR]

In the close vicinity of Yellice (Çetinkaya-Sivas), ophiolitic rocks which were trusted tectonically before Maastrichtian over Munzur limestones of Taurus platform form the basement. Post-tectonic basin deposits (Saya formation and Sincan group) cover them unconformably. Magmatic activity observed in the field is characterized by granitic rocks of Upper Cretaceous and/or subsequent ages, and volcanics of Plio-Quarternary. The ores which is the subject of this study, are mainly composed of magnetites and located within serpentinized ultramafic rocks of the ophiolites. Primary ore minerals of the Yellice area, consist of chromite, magnetite, machinavite droplets bearing pentlandite, pyrrhotite, cubanite lamellae bearing chalcopyrite and pyrite disseminations characterizing liquid magmatic phase. In addition to this primary paragenesis of chromite, magnetite and sulphide assemblages, secondary magnetite minerals formed from iron elements released intensively from ferromagnesian minerals during serpentinization processes which characterize subsequent phase. Small amount of pyrite and silicate minerals accompanied with these assemblages. In general, the average compositions of serpentinized ultramafic rocks are 20.34 % Fe2O3 (total Fe), 0.26 % MnO, 33.19 % MgO, 1.08 % CaO, 0.14 % Al2O3, 31.99 % SiO2, 0.18 % K2O, 0.08 % Na2O with 5678 ppm Cr2O3, 1772 ppm Ni, 191.7 ppm Co, 280 ppm V2O5 and 163 ppm TiO2. Loss on ignition is 10.49 %. In this study area, the ore seen as lenses within serpentinites, comprises mainly magnetite, and reveals an average grade of 18-20 % Fe3O4 with visible and probable tonnage of 125 million tons. At the early stages of the iron formation, it had started to develop as disseminations within ultramafic rocks and gained intensity subsequently by the minerals formed by iron elements released from the ferromagnesian minerals such as olivine and pyroxene during the serpentinization processes of the ultramafic rocks. [ABSTRACT FROM AUTHOR]

The authors offer a new methodology for evaluating complexity of geological structure of ore deposits and base the determination procedure of criteria for comparing effects exerted by geological structure constituents on a chosen geotechnology. [ABSTRACT FROM AUTHOR]

Abstract: The dissolution of soluble minerals may influence the mechanical properties of soils used in earth structures or foundations and may compromise the safety of such structures. This study focuses on changes in the physical properties of soluble mixtures (salt–sand mixtures) during dissolution. Experimental and numerical studies are performed to monitor the behavior of particulate materials during the dissolution process in soluble mixture. Experimental results show that during salt dissolution the shear wave velocity decreases, and subsequently increases to a stable value. Dissolution initiated from the bottom plate causes shear wave velocities to increase slightly in the upper layer, as a result of fabric changes, arching (force chain) generation, and horizontal stress locking. Numerical results show that the mixture fabric changes to a more anisotropically packed state, and becomes more unstable, due to the dissolution. The experimental and numerical results provide valuable insights into the micro-behaviors of soluble mixtures. [Copyright &y& Elsevier]

Abstract: In this paper, the capability of determining the three dimensional (3D) ground displacements due to underground mining using the multiple ALOS PALSAR interferometric pairs acquired with different viewing geometries has been investigated and validated in the area of West Cliff colliery, New South Wales (NSW), Australia. Four ALOS PALSAR interferometric pairs acquired with two different incidence angles from both ascending and descending orbits were used in this study. Three different approaches were used to derive the 3D displacement maps. The first two approaches utilised SAR data only, while the third approach required a one dimensional measurement by using other surveying techniques as inputs. The results were compared with the GPS field survey data obtained between April and May 2008. The obtained results and the GPS data agreed well with each other in the vertical and the east–west directions. However, the precision of displacement measured in the north–south direction was much poorer for the first two approaches compared to the third approach. This was due to two reasons: (1) the lack of viewing geometries, and (2) the poor temporal overlap in the interferometric combination datasets. The results suggested that it is possible to use other one dimensional surveying techniques to assist the InSAR measurements in order to enhance the accuracy of the 3D deformation derived. The horizontal movements in transverse and longitudinal directions were calculated from the 3D deformation results, in order to derive the subsidence parameters that have been caused by mining activities. The subsidence parameters derived matched well with the GPS-derived parameters. The results suggested that an accurate 3D displacement vectors can be derived by combining InSAR-measurement with measurement from other equipment such as extensometer and optical fibre which may carry out measurement in one direction only (ideally north–south direction). [Copyright &y& Elsevier]

In order to effectively control gas unbalance phenomenon of gas occurrence in coal mine, this paper put forward the concept of gas enrichment area and gave the general characteristics of gas enrichment area. Based on geological condition in Zhaogu No. 1 Coal Mine, the paper discussed the gas geological features and analyzed the formation mechanism of gas enrichment area in the thick loess-thin bedrock coal seam, and then obtained the recognition method of gas enrichment area by the overlying bedrock characteristic of coal seam. On the basis of which, the gas enrichment area of Zhaogu No. 1 Coal Mine was confirmed, that was the bedrock layer thickness greater than 50 m and coal seam overlying bedrock gradient greater than 0. 06 or the bedrock layer thickness greater than 150 m area. Coal mining practice verified gas enrichment area identification and actual gas occurrence consistency. [ABSTRACT FROM AUTHOR]

The experience of forecasting the processes accompanying the transformation of large quarries to lakes is presented. Revitalization principles are formulated for the territories disturbed by mining. Developing the landscape and architectural planning scheme of a territory should be the first stage. Basing on the natural renewal processes, it is possible to create with minimal expenses the landscapes which excel in their qualities those existing before mining. For project substantiation it is necessary to make the forecasts of coastal processes development, of dynamics of excavation pit inundation, of water chemical composition formation, and of changes in groundwater regime. The types and scope of postmining are determined on the basis of forecasts of sites and scale of phenomena being dangerous for certain objects. The need in protection activities is determined comparing the possible damage to its prevention expenses. [ABSTRACT FROM AUTHOR]

Abstract: Underground coal fires pose a threat to the environment and the health of those living in their proximity and can result in economic losses if these fires occur at mining areas. Design of methods to extinguish these fires requires that the extent of the subsurface fire be delineated. A conceptual picture of the workings of a subsurface coal fire near Durango, CO is presented first, which shows how the overburden above the burning coal seam can become heated. In high temperature and low O2 conditions, the heating of the overburden leads to the formation of magnetite, and its presence and the alignment of magnetic moments can be detected by a magnetometer. Magnetometer surveys allow high resolution areal mapping that differentiates among previously burned, currently burning, and unburned coal seam areas. The current and previous locations of the subsurface fire regions that are delineated by the magnetometer survey conducted at a fire on the Southern Ute Indian Reservation are consistent with various supporting data such as gas composition, temperature, and snowmelt data. [Copyright &y& Elsevier]

The exhaustive research developed to fluorite prospecting and mining in Llanera, Siero, Colunga, Caravia and Ribadesella, has enabled detailed knowledge about cartographic, stratigraphic and tectonic features in the asturian Permian-Triassic basin. For this paper there have been selected the main contributions effected by geologists -many of them foreigners- that took part in this activity. Most maps and structural sections came from unpublished companies documents or doctoral theses, so they were neither gathered nor integrated into current used geological maps in Asturias. [ABSTRACT FROM AUTHOR]

Abstract: Increasing usage of cemented paste backfill (CPB) in underground mines combined with the fact that every single mine or backfill structure is unique with regards to their temperature conditions require a need to clarify and quantify the effect of curing temperature on the mechanical properties of CPB. Hence, the main objective of this study is to use an experimental approach to study the influence of curing temperature and combined effect of temperature and CPB components on the main mechanical properties (strength, modulus of elasticity, and stress–strain behaviour) of CPB. Thus, different types of CPB specimens are tested at different curing times and temperatures (2°C, 20°C, 35°C, and 50°C). The compressive and split tensile strength, modulus of elasticity, stress–strain behaviour and microstructure are evaluated by laboratory tests. The results show that the curing temperature has a significant influence on the mechanical properties of CPB. Moreover, the effect of temperature on these properties depends on the binder type, W/C ratio, tailings type and curing time. The study demonstrates that the mine and backfill temperatures are an important parameter that should be considered in mine backfill operations. [ABSTRACT FROM AUTHOR]

In Romania the sudden cessation of mineral resources exploitation and processing activity has caused a strong impact on both environment and community. After the closure of mining activity have remained many waste mining deposits, empty spaces, equipments and constructions, etc. managed faulty. In the last few years, the copper exploitation at Rosia Montana has proved that the activity of the mining sector is profitable even in the case of law content deposits and exporting concentrates. At the beginning of the years 2000, the exploitation of non-ferrous ores was considered a non-sense. This assessment has been one of the elements that led to the decision of closing non-ferrous ores mining activity. The destruction of the processing capacities and metal transformation plant in finished product had economic and social impact, losing added value obtained after mining concentrate processing and capitalizing the finished product. [ABSTRACT FROM AUTHOR]

The article reports on the history, geology and mineralogy of the fissure veins of Keweenaw County in the Michigan Copper County. The deposits in the fissure veins that established the discovery and development of the amygdaloidal and conglomerate loads, is the precursor of the first mining rush in the U.S. The mining site, before its closure produced million pounds of copper in its 132-year of operation. Other details about Keweenaw County as a mining site are also presented.

Cadmium is intimately connected to Idaho through mining practices and other emissions of this toxic metal into the environment. Since aquatic organisms can serve as bioindicators to assess the possible impact of heavy metal contaminants, we used liver (AlLW1), gonadal (RTG-2), and gill (RTgiIl-W1) cell lines derived from rainbow trout to investigate cadmium-induced cytotoxicity. We hypothesize RTgill-W1 cells, which are frequently exposed to heavy metal contaminants, are more resistant to cadmium compared to RTL-W1 or RTG-2 cells. Cells were exposed to 200 pM or 500 pM cadmium chloride (CdCI2) for 0, 3, 12, 24 or 48 hours. Parameters assessed were cell morphology by phase-contrast microscopy, loss of adherence, and viability using a trypan blue exclusion assay. RTgill-W1 cells were more resistant to 200 pM CdCl2 compared to RTL-W1 and RTG-2 cells. When exposed to 500 μM CdCl2, RTgillWi remained more resistant (29.2 % viability), followed by RTG-2 (8.4% viability), and RTL-W1 cells (1.0% viability) at 48 hours. For comparison, we examined the effect of cadmium exposure on primary gill cells isolated from live rainbow trout to the lRTgill-W1 cell line. There was no difference in viability between RTgill-W1 and primary gill cells exposed to 200 pM CdCl2. When exposed to 500 pM CdCl2, primary gill cells were more resistant compared to RTgill-W1 cells. Collectively, RTgill-W1 and primary gill cells are more resistant to cadmium than RTL-W1 or RTG-2. This differential sensitivity to cadmium provides a model for elucidating the intracellular mechanisms by which cells respond to and protect against cadmium's toxic action. Furthermore, this research illustrates the importance of using multiple cell lines to access cytotoxicity in response to heavy metal contaminants. [ABSTRACT FROM AUTHOR]

Long before the science of geology was established, the Derbyshire lead miners used elementary practical geology in laying out the lines of their soughs, or drainage levels, to gain any possible advantage of easier excavation. Their objective was to lower the water table, so as to make the deeper parts of mineral veins available for exploitation. [ABSTRACT FROM AUTHOR]

This paper critiques the approach taken by the Ghanaian Government to address mercury pollution in the artisanal and small-scale gold mining sector. Unmonitored releases of mercury—used in the gold-amalgamation process—have caused numerous environmental complications throughout rural Ghana. Certain policy, technological and educational initiatives taken to address the mounting problem, however, have proved marginally effective at best, having been designed and implemented without careful analysis of mine community dynamics, the organization of activities, operators’ needs and local geological conditions. Marked improvements can only be achieved in this area through increased government-initiated dialogue with the now-ostracized illegal galamsey mining community; introducing simple, cost-effective techniques for the reduction of mercury emissions; and effecting government-sponsored participatory training exercises as mediums for communicating information about appropriate technologies and the environment. [Copyright &y& Elsevier]

Lead isotope analysis was applied to Egyptian materials from the Late Bronze Age in order to investigate the relationship between these different materials, many of which have lead as a significant component. The galena kohls analysed can be provenanced to Gebel Zeit, a large mining site known to have been active during the period. However, the source of lead metal is different and seems to be outside Egypt, along with the source of copper. Lead-based pigments such as lead antimonate that were used in glass and glazes seem mostly to come from Egypt, although they may well contain a component of ‘Mesopotamian’ lead. In the Predynastic period, galena from many sources is being exploited for use as kohl. However, by the Middle Kingdom (2055–1650bc), extraction has concentrated on one source, Gebel Zeit, perhaps reflecting increasingly centralized control and/or the use of large-scale exploitation. It therefore appears that a complex pattern of trade in lead-based materials was evident, with lead metal and galena being separate commodities from separate sources and treated as such. [ABSTRACT FROM AUTHOR]

To guarantee the environmental forming from the educational perspective presupposes to confront the challenge of assuming alternative models that allow to change the attitudes, and the individual and collective behavior, and to analyze the incompatibility among the existent human values and those required values to face the development in a sustainable way. This work obeys to the necessity of forming a geological-mining-metallurgical professional who knows how to behave themselves with knowledge of the environment, who makes technical proposals according to the sustainable development. This professional should be flexible and transcendent. This work is centered in the inadequacies that are manifested in the professional performance of the graduated of this profile. As a result of the work, a model of environmental forming for the geological-mining-metallurgical profile has been elaborated, on the base of environmental competence for sustainable development, which contributes to the improvement of the engineer's professional acting. [ABSTRACT FROM AUTHOR]

An optimal combination of mechanical means and microwave energy to break rock material could prove beneficial for space applications in terms of large scale production drilling or rock removal processes. In the present paper, application of low power microwave pulses was used to induce thermal cracks in rock samples, before use of mechanical breakage methods. The present investigation is conducted with the scope of possible space bound and terrestrial applications. Experimental studies were carried out to assess the low power (∼150 W) microwave susceptibility of terrestrial basaltic rock samples (chosen for its close chemical similarity to lunar and Martian rocks). Point load tests were carried out on the microwaved rock samples in order to determine their strength before and after exposure to microwaves. The preliminary experimental results showed that the basalt rock samples used were quite susceptible to the exposure of low power microwaves. From the point load test results, a decreasing trend is observed in terms of strength of the rock samples with microwave exposure duration. Some rock samples even presented visible macro cracking and even splitting for the longest exposure duration used in this experimental program. [ABSTRACT FROM AUTHOR]