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The productivity of the quarry during the wet season heavily depends on how well the personnel adjusts to the mine's environmental conditions and management plans. The improvement of granite production through workers' impact identification and mining advancement decision-making in Ondo State, Nigeria, has been considered in this study. The rate of granite production and the factors influencing workers’ efficiency were assessed using a well-structured survey and descriptive-analytic technique. To improve the production rate, the Multiple Criteria Decision-Making (MCDM) technique was used to select the most productive pit depending on a number of key labor impact factors. Health and safety in employment, the energy crisis, market conditions and level of competition, on-site accidents, natural disasters, and language barriers were some of the factors identified as external influencer factors affecting mine labor efficiency in granite quarrying. Finally, using the criteria's significance through the inter-criterion (CRITIC) approach, the mine workers’ influence on production was estimated and utilized for the best pit selection. The result of the MCDM revealed that the five pits (Pit 1, Pit 2, Pit 3, Pit 4, and Pit 5) had the following decision performance scores: 0.659, 0.617, 0.5, 0.5, and 0.5, respectively. This made Pit 1 the best production pit to be considered during the rainy season. The optimal solution was validated with the 2021 production report. The report shows that production from Pit 1 had the highest revenue of $16,000 Per annum, the lowest dewatering cost, and the highest production rate compared to the other four pits. [ABSTRACT FROM AUTHOR]

An extended area of quarrying activity has been located at Xobourgo, on the Greek island of Tenos, where extraction continued for millennia to the north of the ancient settlement. The quarrying was centered on the protuberance of Xobourgo, a leucogranite outcrop that lies to the southwest of a larger granodiorite zone. The joint study of the material's properties, the quarry's layout, the extraction traces, and the use of leucogranite in constructions at Xobourgo shows that the quarrying activity was related to local building projects, especially fortifications. These are dated to the period that spans from the Early Iron Age (11th-10th century BCE) to the end of the Classical period (end of the fourth century BCE), as well as to the era of Venetian rule (1204-1715 CE). Extraction techniques differed through time depending on available tools, traditions, and the type of masonry. The leucogranite was exploited for its endurance, workability, and aesthetic value. Extraction so close to the adjacent settlement was also advantageous due to low transport costs. High levels of stoneworking skill, in line with the scale of constructions undertaken at the site, are diachronically attested. [ABSTRACT FROM AUTHOR]

National and foreign companies distributed around Huila, Benguela, Kwanza Sul, Kwanza Norte, Cunene and Namibe provinces exploit granite quarries in the Republic of Angola. The main cause effecting the environment caused by this increasingly intense mining activity is the non-existence of sustainability criteria that contribute to a rational and responsible mining operation. The purpose of this study is to establish sustainability criteria for exploiting granite quarries in Hulla province. It was showed by using a four-stage methodology: bibliographical analysis, field work, consulting to specialists and applying the Delphi method that exploiting Huila granite quarries impact vegetation, fauna, soil, surface and ground water, the atmosphere, population, economy and landscape; therefore fifteen sustainability criteria were established for the exploitation of these quarries, each criterion was characterized and their ranges were determined for qualitative and quantitative evaluation. The sustainability criteria obtained can be applied in other similar contexts. [ABSTRACT FROM AUTHOR]

Focuses on the use of railroads to haul stone from quarries in Colorado in 1869. Union Pacific Railroad Co.'s examination of sandstone quarries west of Fort Collins and Loveland in 1880 in light of the expansion of quarries; Formation of the standard gauge Greeley, Salt Lake and Pacific (GSL&P); Real granite quarries in Colorado.

Optimization of cutting operations in quarrying and processing of building stones leads to certain reductions in operational costs. Despite the developments of cutting technology and employment of more efficient cutting machines, there is still a need to optimize a series of operational parameters; the cutting direction is one of them. In order to optimize the cutting direction parameter in cutting processes, an experimental study was designed in a granite quarry. For this purpose, 12 granite samples along 12 different directions with 15° intervals were cut by a special laboratory wire cutting machine. The obtained cutting rate showed that different cutting directions demonstrate very diverse cutting rates. A significant difference of 43% was found between the highest and lowest cutting rates. Also, the optimal cutting direction was found to be 185° relative to the geographical north. Furthermore, microscopic studies on petrographic thin sections were performed to analyze the cutting rate results. Analysis showed that the rock's equivalent hardness was not correlated to the cutting rate, while there is a possible direct relationship between the quartz content and the cutting rate. Besides, results confirmed the currently identified splitting planes of the quarry and showed a potential relationship with the main fault system of the area. [ABSTRACT FROM AUTHOR]

Re-naturalized quarry lakes are important ecosystems, which support complex communities of flora and fauna. Microorganisms associated with sediment and water form the lowest trophic level in these ecosystems and drive biogeochemical cycles. A direct comparison of microbial taxa in water and sediment microbial communities is lacking, which limits our understanding of the dominant functions that are carried out by the water and sediment microbial communities in quarry lakes. In this study, using the 16S rDNA amplicon sequencing approach, we compared microbial communities in the water and sediment in two re-naturalized quarry lakes in Singapore and elucidated putative functions of the sediment and water microbial communities in driving major biogeochemical processes. The richness and diversity of microbial communities in sediments of the quarry lakes were higher than those in the water. The composition of the microbial communities in the sediments from the two quarries was highly similar to one another, while those in the water differed greatly. Although the microbial communities of the sediment and water samples shared some common members, a large number of microbial taxa (at the phylum and genus levels) were prevalent either in sediment or water alone. Our results provide valuable insights into the prevalent biogeochemical processes carried out by water and sediment microbial communities in tropical granite quarry lakes, highlighting distinct microbial processes in water and sediment that contribute to the natural purification of the resident water. [ABSTRACT FROM AUTHOR]

Highlights • The granite sludge has been used as SCM in the design of the new blended cements. • Granite quarry dust exhibits no alkali-silica reactivity. • Binder bearing 20% granite quarry dust are low heat cements. • The new cements are apt for aesthetically sensitive applications. • The new blended cements have good durable behaviour. Abstract Cements prepared to new designs in which different types of waste are used as additions must be tested for mechanical strength and durability to ensure their performance will be satisfactory throughout their service life. This study explored the effect of adding 10% or 20% granite quarry dust to cement on properties such as transport (total and capillary water absorption and electrical resistivity), dimensional stability (drying shrinkage and expansion), the alkali-silica reaction, heat of hydration and colour. No alkali-silica reaction was observed in the new materials and expansion and contraction were less intense than in conventional cement. The water absorption and capillary absorption coefficients rose less in the additioned cements than the replacement ratio, whilst their higher resistivity values afforded greater corrosion protection than found in the reference. The inclusion of this waste also prompted a rise in lightness and a decline in peak heat of hydration. The multivariate analysis of variance (MANOVA) conducted showed that the factors time and replacement ratio affected the properties significantly, whereas the combined effect of the two was statistically significant or otherwise depending on the property analysed. The findings showed that the partial replacement of cement with quarry dust is not detrimental to product durability and the recycled material qualifies as a strength class 42.5, type II/A binder. The materials bearing 20% granite quarry dust, in turn, were found to meet the requirements to qualify as low heat cements (CEM II/A LH). [ABSTRACT FROM AUTHOR]

There are a wide range of magmatism and mineralization in the Yunkai area of South China during the Late Yanshanian Period, including the newly discovered Michang, Youmapo, Sanchachong and Songwang porphyry-skarn W-Mo deposits. In this study, we obtained zircon U-Pb ages of the ore-bearing biotite granites and their mafic enclaves from 88±1 to 110±1 Ma. Zircons from the granites show Hf isotopic compositions with negative εHf(t) values of -5.9 to -0.6 and calculated Hf model ages (TDM2) of 1.5-1.2 Ga; indicating that the Middle Proterozoic crustal materials may have provided an important source for the magmatic rocks in this district during the Late Yanshanian Period, whereas zircons from the mafic enclaves show positive εHf(t) values of 1.3 to 10.1 with younger Hf model ages (TDM2) of 0.5-1.1 Ga, suggesting a mantle component may have involved in the granitic magma generation. Sulfur isotope study of the sulfide minerals from the W-Mo deposits show a narrow δ34S distribution with most data ranging from -4.2‰ to 5.2‰. In addition, this study reports the first Fe isotopic compositions of pyrite in the W-Mo deposits, which show a uniform distribution range with the values near zero (δ56Fe=0.16‰-0.58‰, average 0.35‰; δ57Fe=0.02‰-0.54‰, average 0.48‰). These data indicate that the ore-forming materials may come from the deep-sourced granitic magma, and the mineralizations show a close relationship with the granitic magmatism during the Late Yanshanian Period. Combining with previous results, we suggest that there is a widespread porphyry-skarn W-Mo mineralization in the Yunkai area during the Late Cretaceous (80-110 Ma), which has a close relationship with the Late Yanshanian magmatism that may have formed during the rollback of the subducted Pacific Plate. [ABSTRACT FROM AUTHOR]

Evaluating the reserves of commercial blocks in dimension stone quarries requires determining in situ block geometry. Furthermore, to extract blocks, the planes need to be cut, and the intersection between the fracture network and the cutting patterns forms smaller blocks. The optimization of the cutting patterns can increase quarrying efficiency, resulting in less environmental damage. In this paper, a numerical algorithm was selected from various algorithms and was developed for in situ block identification. The optimization approach was adopted to increase quarry productivity and to investigate quarrying direction on a large scale. However, on a small scale, this approach was employed for checking the distance between the cutting planes. According to the algorithms developed, 3D-QuarryOptimizer was programmed in the MATLAB environment to determine the geometry of the blocks and to optimize extraction based on the quality classification of the blocks formed. The algorithms developed have such advantages as the optimization approach and taking the geometry of the blocks into consideration. This methodology was applied in a marble quarry and a granite quarry. Research conducted in the granite quarry showed that the program is a practical tool to determine the geometry of in situ blocks and their quality classification. The marble quarry was studied for the optimization phase. The large-scale optimization indicated a maximum difference of 17% in the yield among several quarrying directions. On a small scale, however, a 120% increase in quarry yield was achieved with the optimal interval between the cutting planes. [ABSTRACT FROM AUTHOR]

The U-Pb (ID TIMS) geochronological studies of single zircon grains and their fragments have made it possible to establish that rare-metal alkaline granites of the Katugin massif (2055 ± 7-2066 ± 6 Ma) underwent high-temperature transformations at age levels of ~1921 ± 5 and 1876 ± 7 Ma. [ABSTRACT FROM AUTHOR]

This paper presents the case study of a stability analysis of an over-tilted (inverse) slope in an ornamental granite quarry. Based on traditional small quarrying practices and due to space constraints, the SW slope was carved following the occurrences of highly persistent joints that were dipping around 80° counter-slope. Experience dictates that this sort of slopes tends to be unstable, at least in case of average to low quality rock masses. In this way, a stability analysis was due to analyze slope stability. The good quality granite rock mass in the slope was characterized, joint data was recorded and laboratory testing was done to estimate the main significant parameters involved in the study and the geometry of the slope. A stability analysis of the slope was performed by means of the calculations of safety factors against toppling. These calculations have been done contemplating various possibilities regarding the occurrence of joints and its spacing, which was found to be the most relevant parameter controlling stability. [ABSTRACT FROM AUTHOR]

Background: Pure water is an absolutely necessary component of the earth not only for life but also for sustainable socio-economic development of today's civilization. The aim of this study was to analysis the quality of water resources and to investigate the influences of mining activities on water quality around the Maddhapara Granite Mining area, Dinajpur, Bangladesh. Result: 31 samples from surface and groundwater were collected from this selected area to assess their hydrochemistry, suitability, and their possible sources of contamination. Consequently, in the case of physico-chemical analysis, the 24 parameters such as P, Electrical Conductivity, TDS, TH, Ca, Mg, K, Cd, Cr, Cl, $${\text{SO}}_{4}^{{2{ - }}}$$ , $${\text{PO}}_{4}^{3 - }$$ , $${\text{NH}}_{4}^{ + }$$ , $${\text{NO}}_{3}^{{ - }}$$ , $${\text{HCO}}_{3}^{{ - }}$$ etc. were analyzed in laboratory. Multivariate statistical methods were adopted for determining the water quality and their sources of contamination. The Gibbs ratio plot suggests that most of the samples fall in the rock dominance fields and some are in the precipitation dominance field. Cluster analysis confirms that three main groups of water samples where cluster I includes 70.97% of water samples, cluster II and cluster III includes rest 22.58 and 6.45% of the water samples respectively. Factor Analysis/Principal Component Analysis (FA/PCA) illustrates five factors extracted which explain 75.89% of the total variance. Conclusion: The collective results of multivariate analysis and Water Quality Index implies that most of the areas around the mining area are dominated by the good to excellent quality water for different purposes. In addition, the results of this research will then be helpful to estimate the major sources of contamination in different areas within the framework of activities intending to improve the quality of water. [ABSTRACT FROM AUTHOR]

The South Um Mongul prospect is a Cu-Mo-Au porphyry system. It is covered by porphyritic dacite and hornblende gabbro. Both units are intruded by monzogranite, which encloses xenoliths of both units. Using LA-ICP-MS U-Pb zircon method, the dacite is dated at ca. 773 ± 6.9 Ma, while the gabbro and the monzogranite are dated at 603 ± 3.5 and 558 ± 4.6 Ma, respectively. The dacite age is consistent with the mid-Cryogenian subduction-related magmatic stage and the gabbro-monzogranite age is comparable to the Ediacaran post-collisional magmatic stage during the evolution of the Arabian-Nubian Shield. The dacite is akin to high-K I-type granitoids and its primitive mantle-normalized trace element patterns show negative Nb anomalies and enrichment in LILE (large ion lithophile elements), Th and U over HFSE. These geochemical characteristics are similar to those of felsic magma formed in a subduction-related tectonic setting. The high La/Yb cn (7.2–30.9), Nb/Yb (2.63–4.41) and Th/Yb (2.07–3.04) ratios of the dacite are comparable to continental rather than oceanic arc systems. Its low Sm/Yb ratios (1.84–3.13) support the primitive nature of the crust beneath the continental arc and derivation from a garnet-free lower crustal source. The dacite has low Sr/Y ratios (5–9) and its Eu/Eu ⁎ ratios range from 0.66 to 0.83. Similar to dacite, the primitive mantle-normalized trace element patterns of the post-collisional suite show a subduction-related geochemical signature. However, the gabbro is characterized by Th/Ta ratios (3.4–14.8), which are comparable with the within-plate tectonic setting. The subduction-related geochemical signature is inherited from long subduction history beneath the Arabian-Nubian Shield. Both the gabbro and monzogranite are characterized by high Ba (404–590 ppm and 936–1590 ppm, respectively) and Sr (611–708 ppm and 624–793 ppm, respectively) contents, which make them analogous to the Caledonian appinite-high Ba-Sr granite assemblage. The formation of these rocks is related to the Ediacaran lithospheric erosion accompanying slab break-off. This process induced asthenospheric upwelling, which led to partial melting of the lithosphere previously metasomatised by subducted sediments involving carbonates impregnated by hydrothermal barite. Melting of this lithosphere led to the formation of the hornblende gabbro. Underplating by the mafic magma led to melting of the lower crust and the formation of high Ba-Sr monzogranite in the area. The high Sm/Yb (2.94–4.19) and Sr/Y (52–74) ratios of the monzogranite may indicate the presence of garnet in the melted amphibolitic lower crust. The higher Sr/Y ratios, lower HFSE (high field strength elements) contents and the absence of pronounced Eu anomalies in monzogranite relative to dacite suggest the productive nature of the post-collisional magma relative to the continental arc magma in this prospect. [ABSTRACT FROM AUTHOR]

Most of the hydrothermal uranium (U) deposits from the European Hercynian belt (EHB) are spatially associated with Carboniferous peraluminous leucogranites. In the southern part of the Armorican Massif (French part of the EHB), the Guérande peraluminous leucogranite was emplaced in an extensional deformation zone at ca. 310 Ma and is spatially associated with several U deposits and occurrences. The apical zone of the intrusion is structurally located below the Pen Ar Ran U deposit, a perigranitic vein-type deposit where mineralization occurs at the contact between black shales and Ordovician acid metavolcanics. In the Métairie-Neuve intragranitic deposit, uranium oxide-quartz veins crosscut the granite and a metasedimentary enclave. Airborne radiometric data and published trace element analyses on the Guérande leucogranite suggest significant uranium leaching at the apical zone of the intrusion. The primary U enrichment in the apical zone of the granite likely occurred during both fractional crystallization and the interaction with magmatic fluids. The low Th/U values (< 2) measured on the Guérande leucogranite likely favored the crystallization of magmatic uranium oxides. The oxygen isotope compositions of the Guérande leucogranite (δ 18 O whole rock = 9.7–11.6‰ for deformed samples and δ 18 O whole rock = 12.2–13.6‰ for other samples) indicate that the deformed facies of the apical zone underwent sub-solidus alteration at depth with oxidizing meteoric fluids. Fluid inclusion analyses on a quartz comb from a uranium oxide-quartz vein of the Pen Ar Ran deposit show evidence of low-salinity fluids (1–6 wt.% NaCl eq.), in good agreement with the contribution of meteoric fluids. Fluid trapping temperatures in the range of 250–350 °C suggest an elevated geothermal gradient, probably related to regional extension and the occurrence of magmatic activity in the environment close to the deposit at the time of its formation. U-Pb dating on uranium oxides from the Pen Ar Ran and Métairie-Neuve deposits reveals three different mineralizing events. The first event at 296.6 ± 2.6 Ma (Pen Ar Ran) is sub-synchronous with hydrothermal circulations and the emplacement of late leucogranitic dykes in the Guérande leucogranite. The two last mineralizing events occur at 286.6 ± 1.0 Ma (Métairie-Neuve) and 274.6 ± 0.9 Ma (Pen Ar Ran), respectively. Backscattered uranium oxide imaging combined with major elements and REE geochemistry suggest similar conditions of mineralization during the two Pen Ar Ran mineralizing events at ca. 300 Ma and ca. 275 Ma, arguing for different hydrothermal circulation phases in the granite and deposits. Apatite fission track dating reveals that the Guérande granite was still at depth and above 120 °C when these mineralizing events occurred, in agreement with the results obtained on fluid inclusions at Pen Ar Ran. Based on this comprehensive data set, we propose that the Guérande leucogranite is the main source for uranium in the Pen Ar Ran and Métairie-Neuve deposits. Sub-solidus alteration via surface-derived low-salinity oxidizing fluids likely promoted uranium leaching from magmatic uranium oxides within the leucogranite. The leached out uranium may then have been precipitated in the reducing environment represented by the surrounding black shales or graphitic quartzites. As similar mineralizing events occurred subsequently until ca. 275 Ma, meteoric oxidizing fluids likely percolated during the time when the Guérande leucogranite was still at depth. The age of the U mineralizing events in the Guérande region (300–275 Ma) is consistent with that obtained on other U deposits in the EHB and could suggest a similar mineralization condition, with long-term upper to middle crustal infiltration of meteoric fluids likely to have mobilized U from fertile peraluminous leucogranites during the Late Carboniferous to Permian crustal extension events. [ABSTRACT FROM AUTHOR]

The characterisation of the late Variscan intrusion of Monte Linas (southern Sardinia) allowed to firstly study some Sn-bearing ores of this area and their relationships with the surrounding intrusives. The Monte Linas pluton was emplaced at ca. 290 Ma at a shallow crustal level between allochthonous units and the foreland of the Sardinian Variscan belt. The pluton emplaced in a post-collisional regime into a previously exhumed low-grade basement, forming a coarse-grained monzogranite that is capped by an almost continuous sub-horizontal sheet of fine-grained rocks. The rocks within the pluton are ferroan F-bearing granites, belonging to the ilmenite-series. They have alumina saturation index values indicative of sub-aluminous to slightly peraluminous granitoids, as also indicated by the chemical composition of biotite within the pluton. The new data of this study indicate that the Monte Linas pluton formed from water-undersaturated magmas under low- f O 2 conditions at temperatures > 850 °C. The later stages of magmatism were characterised by boiling and fluid expulsion at confining pressures of < 1 kbar, producing fayalite-bearing pegmatites, miarolitic facies and greisening. A wide variety of mineral deposits are associated with the Monte Linas pluton, including different types of Sn-bearing and Mo-bearing ores. Sn-bearing ores are represented by 1) Sn–As and Sn–Pb–Zn–Cu veins, and 2) “wrigglite” skarn Fe-Zn-Sn ores. Field and analytical studies, including fluid inclusion analyses, EMPA and SEM-EDS, allow to refer these deposits to the evolution of initial highly saline, hypothermal magmatic fluids, as confirmed by parageneses and fluid inclusion analyses of cassiterite in veins, which provide evidence of polyphase processes that started at temperatures close to 400 °C. The hydrothermal systems were initially characterised by low- f O 2 and high-chlorine solutions that mobilised Sn and underwent rapid changes in physicochemical conditions that led to the deposition of cassiterite. In the “wrigglite” F-rich genetic environment, a role of fluoride as complexing agent for Sn can be inferred. The Monte Linas pluton is also characterised by Mo deposits, not typical in ilmenite series granites; they occur both as greisens and veins. Mo was mobilized as a result of rapid increases in f O 2 within the magmatic system, and precipitated in a f S 2 -rich environment nearby the contact between the intrusion and the surrounding country rocks. The variety of Sn mineralising events around the Monte Linas pluton confirms the role of physicochemical characters of magmas and of magmatic processes in the genesis of tin deposits. The occurrence in southern Sardinia of a wide suite of ilmenite-series ferroan granites emplaced in similar geological contexts allows to consider the idea of a low-grade tin province and opens the way to further explorations. [ABSTRACT FROM AUTHOR]

A quality study of the drained water from Maddhapara Granite Mine underground tunnel was undertaken to study their hydrochemical variations and suitability for various uses employing chemical analysis, basic statistics, correlation matrix ( r), cluster analysis, principal component/factor analyses, and ANOVA as the multivariate statistical methods. The results of chemical analysis of water show the modest variation in their ionic assemblage among different sampling points of the tunnel where Ca-HCO type of hydrochemical facies is principally dominated. The correlation matrix shows a very strong to very weak positive, even negative, correlation relationship, suggesting the influence of different processes such as geochemical, biochemical processes, and multiple anthropogenic sources on controlling the hydrochemical evolution and variations of water in the mine area. Cluster analysis confirms that cluster 1 contains 68.75% of total samples, whereas cluster 2 contains 31.25%. On the whole, the dominated chemical ions of first cluster groups are Ca and HCO, suggesting a natural process similar to dissolution of carbonate minerals. The second cluster group consisted of Cl and SO ions representing natural and anthropogenic hydrochemical process. The results of PCA/FA analysis illustrate that different processes are involved in controlling the chemical composition of groundwater in the mine area. The factor 1 loadings showed that pH, EC, TDS, Na, Mg, chloride, and sulfate which have high loading in this factor are expected to come from carbonate dissolution to oxidation conditions. One-way ANOVA describes the significance of dependent variables with respect to independent variables. ANOVA gives us the idea that EC, K, Fe, SO, As, and Pb are the most important factors in controlling spatial differences in water quality in this tunnel. But different results have been encountered for different independent variables which might be due to dissimilar sources of water. From the qualitative analysis, it is clear that water quality is not very favorable for aquatic creatures as well as for drinking purposes. The water can be used for irrigation purposes without any doubt as SAR and RSC analysis provides good results. Moreover, the results of this research confirmed that the application of multivariate statistical analysis methods is apposite to inferring complex water quality data sets with its possible pollution sources. At the end, this research recommends (1) as water becomes more and more important, water treatment plants should be built before the water being used; (2) a detailed water step utilization plan should be set beforehand to guarantee tunnel water being used effectively; and (3) after the water being used for agriculture, elements in crops should be monitored continuously to ensure that ions and compounds that come from the tunnel water are lower than guideline values for human beings health. [ABSTRACT FROM AUTHOR]

This paper is aimed to systematically assess greenhouse gases (GHGs) and energy intensity of the granite rock mining operations in Thailand and also identify a range of feasible options to minimize their GHG emissions. Mining factories A, B and C, located in the Eastern region of Thailand, were selected as research case studies. The results indicated that the 3-year average of GHGs emissions from factories A to C was 3387 718 kgCO2e per year with approximately 2.92 kgCO2e per ton of granite rock produced over 2012 to 2014. Of this, the carbon intensity of grid-electricity consumption for the crushed rock production was 1.84 kgCO2/kWh. Diesel fuel combustion for transport activities in the mining factories was the greatest contributor to GHGs emissions (68 %) compared to the purchased electricity and explosion process, with 31 % and 1 %, respectively. In-Pit Crushing and Conveying (IPCC) installation, haul truck payload optimization and management, and reduction in tire rolling resistance have shown potential to reduce carbon emissions accounted for 20 % to 70 %. [ABSTRACT FROM AUTHOR]

This research was aimed at developing a new model to predict flyrock distance based on a genetic programming (GP) technique. For this purpose, six granite quarry mines in the Johor area of Malaysia were investigated, for which various controllable blasting parameters were recorded. A total of 262 datasets consisting of six variables (i.e., powder factor, stemming length, burden-to-spacing ratio, blast-hole diameter, maximum charge per delay, and blast-hole depth) were collected applied to developing the flyrock predictive model. To identify the optimum model, several GP models were developed to predict flyrock. In the same way, using non-linear multiple regression (NLMR) analysis, various models were established to predict flyrock. Finally, to compare the performance of the developed models, regression coefficient ( R ), root mean square error (RMSE), variance account for (VAF), and simple ranking methods were computed. According to the results obtained from the test dataset, the best flyrock predictive model was found to be the GP based model, with R = 0.908, RMSE = 17.638 and VAF = 89.917, while the corresponding values for R , RMSE and VAF for the NLMR model were 0.816, 26.194, and 81.041, respectively. [ABSTRACT FROM AUTHOR]

Mines, quarries and construction sites face environmental impacts, such as flyrock, due to blasting operations. Flyrock may cause damage to structures and injury to human. Therefore, flyrock prediction is required to determine safe blasting zone. In this regard, 232 blasting operations were investigated in five granite quarries, Malaysia. Blasting parameters comprising maximum charge per delay and powder factor were prepared to predict flyrock using empirical and intelligent methods. An empirical graph was proposed to predict flyrock distance for different powder factor values. In addition, using the same datasets, two intelligent systems, namely artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) were used to predict flyrock. Considering some model performance indices including coefficient of determination ( R), value account for and root mean squared error and also using simple ranking procedure, the best flyrock prediction models were selected. It was found that the ANFIS model can predict flyrock with higher performance capacity compared to ANN predictive model. R values of testing datasets are 0.925 and 0.964 for ANN and ANFIS techniques, respectively, suggesting the superiority of the ANFIS technique in predicting flyrock. [ABSTRACT FROM AUTHOR]

The paper looks at how past leaders of Australia’s mining industry embraced downstream processing of mine production in Australia as a natural extension of their businesses. For them, there was unassailable logic in adding maximum value through smelting, refining and manufacturing in Australia, for commercial reasons and for what they perceived to be the national interest. As value-adding activity increased in Australia in the mid-late 20th century, ironically there was vociferous criticism that Australia had become no more than a quarry. Today, at a time when the downstream processing of Australian mine products in Australia is being reduced and Australian processing technologies are being applied in other countries, public discussion is muted. [ABSTRACT FROM AUTHOR]

As a result of the overdependence on river-sand for construction activities, there is need to source for a readily available material with comparable strength when used for certain purposes (in this case, sandcrete hollow blocks). This paper evaluates the compressive strength of sandcrete hollow building blocks when its sand fraction is partially replaced with quarry dust. A range of 0%, 10%, 15%, 20% and 25% sand replacement with quarry dust was used in the cement: sand mix ratios of 1:6 and 1:8 for molding the blocks of size 450mm ? 225mm ? 225mm. These blocks were produced by machine compaction under a pressure of 3N/mm². Results indicate that for mix ratio of 1:6 at 28 days when 10% quarry dust partial replacement was applied, the compressive strength of the blocks was about 7% greater than that of blocks without partial replacement. Also, for the mix ratio of 1:8 at 28 days and 10% partial replacement with quarry dust, the compressive strength of the blocks was about 46% higher than that without partial replacement of the sand fraction. The strength of the blocks increases with increase in quarry dust partial replacement of sand. However, for the mix ratios employed, it is noted that 15% partial replacement of sand with quarry dust gave an optimum compressive strength of 3.8N/mm² and 4N/mm²for the two mix ratios respectively. It is suggested therefore, that the optimum replacement of sand with granite quarry dust as fine aggregates should be 15% of the sand fraction in hollow building blocks of the size and mix ratio adopted herein. [ABSTRACT FROM AUTHOR]

To achieve a smooth fracture plane with minimal damage to a rock block or remaining rock mass, a water-coupling cutting blasting technique was applied in a granite quarry. The mechanism of water-coupling cutting blasting is demonstrated with the specification of prerequisites for crack growing and arresting. Using the LS-DYNA program, the maximum principal stress distribution and rock damage evolution process were observed, and the validity of crack extension till coalescence was verified by comparing the calculated and theoretical water pressure needed to induce fracture. The optimum blasting parameters for achieving the best cutting blasting performance were obtained by simulations under different coupling ratios and blasthole spacings. The successful water-coupling cutting blasting practice in the granite quarry has great potential to be applied in other similar engineering. [ABSTRACT FROM AUTHOR]

Seven soil-gas radon monitoring stations were placed along the active front of a granite quarry in Canas de senhorim, Central Portugal, recording continuously for 81 days. Important differences in the radon concentration were found between stations, with average values comprised between 102 and 2982 Bqm-3, which can be explained by the local presence of uranium anomalies in the regional lateorogenic Hercynian granite, usually associated with faults. One of the boreholes exhibits large radon anomalies lasting for several days, and two, contrary to the others, show a clear daily periodic behaviour, with minima around 19:00 LT and maxima around 07:00 LT. The different patterns observed in stations placed at such a short distance (<100 m) has no clear explanation and deserves further investigation. Data analysis shows no evidence of soil-gas radon concentration changes during explosions carried out at the quarry. This is likely to result from the absence of a progressive stress field affecting the rock, as typically occurs before an earthquake. [ABSTRACT FROM AUTHOR]