The framing of this theme would contribute to a better analysis of the benefits of open-air quarrying in Zinder, and should make it possible to understand and measure the socio-environmental externalities of this type...The framing of this theme would contribute to a better analysis of the benefits of open-air quarrying in Zinder, and should make it possible to understand and measure the socio-environmental externalities of this type of activity in an urban environment. The approach method consisted of carrying out surveys combined with field observations and interviews with the various stakeholders as well as the local population. The results obtained made it possible to identify both positive and negative impacts. The positive impacts are above all the advantages derived from these aggregate quarries, in particular, the creation of direct and permanent jobs and the increase in community income. The price of piling up a truck costs around 28,000 CFA ($56 CAN) and that of loading is around 10,000 F CFA ($20 CAN). This has the effect of removing young people (20 - 39 years old) from the circuit of migration outside the region and even the country. The possibility of using the extraction sites by the local population was identified, in terms of profits relating to fish farming, off-season crops, animal drinking and reclaimed plots. The study also noted negative externalities, such as the temptation of young boys to become involved in extractive activities for immediate gains at the expense of school attendance. Added to this is the upheaval in the topography of the urban landscape, pollution and nuisances (noise, visual and olfactory), while the disappearance or clogging of quarry ponds is the cause of frequent flooding in the neighborhoods. In short, corrective measures (e.g. the revegetation of sites) certainly make it possible to minimize the harmful impacts on the urban environment. But, to improve the performance and organizational capacity of the quarrying industry in Niger, even stronger regulation, training and awareness of stakeholders prove to be the necessary measures.展开更多
Quarrying is an activity contributing to the vitality of the Moroccan economy. However, most of these quarries were abandoned at the end of extraction and became dump and later a place of uncontrolled landfills. The n...Quarrying is an activity contributing to the vitality of the Moroccan economy. However, most of these quarries were abandoned at the end of extraction and became dump and later a place of uncontrolled landfills. The number of restored or rehabilitated quarries is limited and this threatens several aspects of the environment, especially, the quality of surface and ground water, landscape, forests, etc. This also gives rise to increased erosion risk. The study identifies plant species covering 10 abandoned quarries in the region of Rabat, especially the Bouregreg River and its affluent Akreuch in order to define a strategy for their restoration or rehabilitation. Field surveys were led to locate and map 10 abandoned quarries and to sample plant species. Herbaria were established and species were identified and classified. The results of the study distinguished 46 different plant species spread over 45 genera and 27 botanical families. The most dominant family in the quarries visited is Asteraceae. These results will allow us to study the vegetation dynamics in these abandoned lands and serve as a basis, in the selection of appropriate species in eventual restoration or rehabilitation projects.展开更多
The I48TN is one of the 60 International Monitoring System (IMS) stations of the Comprehensive nuclear Test Ban Treaty Organization (CTBTO), characterized by its location in the heart of the IMS Infrasound network. Th...The I48TN is one of the 60 International Monitoring System (IMS) stations of the Comprehensive nuclear Test Ban Treaty Organization (CTBTO), characterized by its location in the heart of the IMS Infrasound network. The ability of the International Monitoring System (IMS) infrasound network to detect atmospheric nuclear explosions and other signals of interest is strongly dependent on station-specific ambient noise. This ambient noise, includes both incoherent wind noise and real coherent infrasonic waves. Infrasound analysis software detects tens to hundreds of events per day which consume a lot of time for the Infrasound analysts, to define and categorize events where around 90% of the detections are coherent noise. This study analyzed the importance of the synergy between infrasound and seismic data, and provided the infrasound data analyst with the most important local coherent infrasound sources in the region as recorded by the IMS station I48TN, in order to reduce the workload of the analysts and give them a clear view on the coherent noise affecting this station for better discrimination between events of interest like nuclear explosions and coherent sources. DTK_GPMCC and DIVA software were used to perform this study. Geotool software from the International Data Centre (IDC) was used in analysing seismic data from the Tunisian IMS station KEST. The result of this study allowed the characterization of the most important coherent local infrasound sources (Mines and Quarries) which are considered as coherent noise to I48TN station and correct parameters in some reference events in the Reference Event Database source of the International Data Centre.展开更多
The management of overburden is an important task in open pit exploitations. Site topography and morphology as well as geological and geotechnical properties of natural and remoulded materials are the most important f...The management of overburden is an important task in open pit exploitations. Site topography and morphology as well as geological and geotechnical properties of natural and remoulded materials are the most important factors affecting the disposal phase. Economic and environmental requirements must be followed in order to achieve the best reclamation results, keeping into account site constraints such as slope stability, hauling and dumping issues, and interactions with groundwater. This paper deals with the above mentioned issues, illustrating a rational approach applied on the case of a large limestone quarry where the thickness of the overburden is relevant and the spoil material has to be dumped in a flooded pit. The proposed multidisciplinary approach led to the selection of most suitable methods for excavation, transportation and disposal. The selection was based on a detailed laboratory and site characterisation that defined favorable and adverse factors to be considered during the preliminary study of a large quarrying project.展开更多
The main objective of this study is to determine the rates of vertically and horizontally oriented drilling processes in marble quarries and to observe the factors affecting the drilling rates in terms of physical and...The main objective of this study is to determine the rates of vertically and horizontally oriented drilling processes in marble quarries and to observe the factors affecting the drilling rates in terms of physical and mechanical properties of the rocks. In situ drilling tests were performed in different marble quarries with different marble types and drilling times and penetration rates for a series of successive depthincrements were trying to be determined under vertically and horizontally oriented conditions. In order to understand the relation between the parameters that are investigated within the scope of this research, uniaxial compressive strength, Brazilian tensile strength, impact strength, Bohme abrasion strength, P-wave velocity, porosity, unit volume weight, Schmidt hardness index and brittleness index values were correlated with the drilling rates. It was noticed that the porosity and unit volume weight could be taken as the key parameters among them for obtaining meaningful correlation with drilling performance. It was also observed that the physical and mechanical rock properties are more relevant in vertical drilling than horizontal drilling.展开更多
The study aimed at assessing the distribution and composition of dust produced at Pomona Stone Quarry mine in Harare, Zimbabwe. The source contribution to ambient PM2.5 and PM10 dust levels were quantified and their s...The study aimed at assessing the distribution and composition of dust produced at Pomona Stone Quarry mine in Harare, Zimbabwe. The source contribution to ambient PM2.5 and PM10 dust levels were quantified and their spatial distribution from the quarry to the receptor (community). The study also analysed the pH of soils around the mine, SiO2 and Al2O3 levels in quarry dust. Data was collected through direct observations, personal communications, experiments, soil and dust sampling and analyses. Dust sampling was done in January, April and August, to assess the effect of meteorological conditions on dust concentrations in two phases. Phase 1 was conducted during plant shut down (baseline measurements) while phase 2 was carried out during full plant operations (normal operating conditions), to assess the effect of quarry operations on the surrounding areas. Within the quarry production processes, crushing stage was the most dust emitting stage. Phase 1 dust results showed that both respirable (PM2.5) and inhalable (PM10) dust at all stages were below the legal limit, thus below 35 mg/m3 (respirable) and 180 mg/m3 (inhalable). Highest dust levels (209.9 mg/m3 inhalable and 69.01 mg/m3 respirable) were recorded in August, followed by April (206.9 mg/m3 inhalable and 67.52 mg/m3 respirable) then January (206.82 mg/m3 inhalable and 65.27 mg/m3 respirable). At all stages, highest dust concentrations for both parameters were recorded near the plant and decreased with increasing distance from the plant ( ranging from 209.9 mg/m3 - 19.41 mg/m3 inhalable and 69.01 mg/m3 - 14.23 mg/m3 respirable). This was attributed to the effect of particle size. August recorded the biggest area for both parameters falling within the non-permissible category, followed by April then January. The findings also revealed that the quarry dust contained higher levels of SiO2 (0.752 mg/cm3) which were 7 times higher than the recommended 0.1 mg/cm3 (NSSA). Low Al2O3 levels of 0.102 mg/cm3 were recorded and this was considered as environmentally safe. Soils were slightly acidic-alkaline and the t-test results at 95% confidence interval showed no significant difference between the results from site A and B (p = 0.526). It was concluded that quarry dust from Pomona had no significant effects on soil pH but possible health impacts on the receiving community. The study recommended that dust suppression systems such as water sprays, vegetation, air nets and enclosed production process must be implemented to curb dust emissions.展开更多
The paper presents a new method for preventing dust pollution in stone quarries using naphthenic wastes of petroleum refineries. The method is based on the use of naphthenate solutions of metals as wetting agents to m...The paper presents a new method for preventing dust pollution in stone quarries using naphthenic wastes of petroleum refineries. The method is based on the use of naphthenate solutions of metals as wetting agents to minimize dust release during stone-cutting process. The studies were carried out in one of the stone quarries of the Absheron peninsula. Initial experiments were conducted by using sodium-naphthenate (RCOONa) solution from alkali wastes of refineries. The results have shown that the use of RCOONa as wetting agent considerably reduces both dust pollution and energy consumption of the used equipment, while increasing the service life of stone-cutting saw. A series of researches were carried out with cupric naphthenate (RCOOCu) to further use the obtained dust-naphthenate mixture in agriculture. The effect of various parameters on the quality of the obtained product was investigated. The investigations have revealed that maximal dust reduction and the good quality of dust-naphthenate mixture were observed with 0.13% solution of RCOOCu at 11° - 13° angle of slope and 100 - 180 rotation∕min. intensity of conveyer.展开更多
Geochemical investigation of the soils around quarry and barite mine sites in part of Akamkpa and Biase area of Southeastern Nigeria, was carried out to assess the concentration and enrichment levels of some heavy met...Geochemical investigation of the soils around quarry and barite mine sites in part of Akamkpa and Biase area of Southeastern Nigeria, was carried out to assess the concentration and enrichment levels of some heavy metals and trace elements in the soils. The investigation involved the collection of fifteen (15) soil samples between the depth of 15 - 30 cm. The samples were dried at room temperature, prepared and analyzed for heavy metals using inductively couple plasma mass spectrometer. The result shows that the concentration of Co, Cr, Nb, Pb and Sn were higher than the average shale values around the quarries while Ba, Pb and Sn were higher around the barite mines. The contamination factor indicates low to minimal contamination and low to considerable contamination around the quarries and barite mines respectively. While the Enrichment factor indicates minimal to significant enrichment around the quarries and minimal to extremely high enrichments around the barite mines. The result of the factor analysis and spatial distribution of the heavy metals suggests that the metal concentration and enrichment were controlled by the rock types, weathering and anthropogenic activities around the mine sites.展开更多
The competition between coral and algae in marine reefs is pervasive through geologic time;that competition determines the structure and composition of reef communities, which we see in the fossil record. However, the...The competition between coral and algae in marine reefs is pervasive through geologic time;that competition determines the structure and composition of reef communities, which we see in the fossil record. However, the relationships between coral and calcareous algae in reefs are poorly understood. To study this relationship, several hand samples and thin sections were examined from nine different foralgal reef localities around the world. Foralgal reefs typically extend from about 20 m depth or shallower on the seaward side of the reef. The first section is Salt Mountain, Alabama, which preserves a Paleocene reef. It contains a high percentage of red coralline algae with benthic foraminifera. The second section is IDOP-U1376, IIA Limestone, it is Middle Eocene, in the form of an isolated reef sandwiched between two igneous beds. The third section is the Utoe’ Limestone, New Caledonia, it is Middle Eocene in age and is composed mainly of grain-boundstone units with some igneous interlayered. The fourth section is the Darnah Formation in the West-Darnah roadcut section, Northeast Libya, it is Middle Eocene in age, it is composed of highly fossiliferous limestone (corals, red coralline algae, echinoids, mollusks, foraminifers, and bryozoans). The fifth section, the Al Bayda Formation (Algal Limestone Member) in Northeast Libya, is in the Drayanah—Al Abyar roadcut, Northeast Libya, it has several species of algae but also includes a high percentage of buildups of coral species. The sixth section is the Oligo-Miocene Al Faidiyah Formation (Al Fatayah Cement Quarry) limestone unit in Northeast Libya. The seventh section is (Core-core 20) late-early to middle Miocene Limestone Unit-Cicuco Field, NW Colombia. The eighth section is the Benghazi Formation at Benghazi Cement Quarry, in Northeast Libya, it is fossiliferous limestone, consisting of coral, algae, mollusks, and echinoids. The ninth and tenth sections are Quaternary reefs in the Bahamas and the Florida Keys, respectively. These reefs contain a high percentage of coral, red coralline algae, echinoids, mollusks, foraminifers, and ostracods. Based on the data and static analysis results on the thin sections and hand specimens, this study determines the occurrence and outcomes of coral-algal interactions among different coral growth forms (branching, upright, massive, encrusting, plating, and solitary). The Early Paleogene (Paleocene to Eocene) has the highest percentage of algae in two forms (crustose and frondose), which is a good indicator of a warm climate. In the Middle Eocene to Late Eocene, coral replaced algae in different localities in sections of that age. This change is an indicator of climatic cooling, especially in the western Lutetian Darnah section. In the Oligocene time, high-branching corals became abundant and escaped competition with the algae due to Icehouse conditions, as shown in the Al Bayda Formation. In the Miocene, coral species started to decline because of the return to Greenhouse conditions. Coral can lose its competitive edge when chemical and physical defense systems reduce growth and production due to warming. On the other hand, crustose-form algae attract the larvae of the coral. Algae induce them to get a more highly competitive frondose form, which is useful for corals as they decrease growth and production. Algae can quickly colonize the dead reef by using the firm substrate to rebuild themselves. This research may prove valuable when predicting the response of modern coral reef systems to future climatic warming conditions and provides a model for what future reefs may look like.展开更多
The exploitation of groundwater by drilling in the Mitendi South-East district constitutes a solution to the water shortage in this peripheral part of the Mont-Ngafula township in Kinshasa, the capital of the DR Congo...The exploitation of groundwater by drilling in the Mitendi South-East district constitutes a solution to the water shortage in this peripheral part of the Mont-Ngafula township in Kinshasa, the capital of the DR Congo. Individuals exploit groundwater in boreholes to serve the population without taking into account certain necessary aspects such as the origin of the groundwater table and the quality which constitute the major problems of this work such as: What is the quantity of water from the recharge of our aquifer? What is the state of the Mitendi South-East aquifer water in relation to some physico-chemical parameters? The cardinal objective of this work is to provide chemical data and trace elements in each analyzed borehole and determine the type of recharge of the underground aquifer. The specific objectives are as follows: analyze the potability of groundwater on a physico-chemical level and their chemical facies, take the geographical coordinates of water samples from the aquifer in each targeted borehole in order to develop the sampling map of the area under study;also check each parameter analyzed in relation to WHO standards. We carried out a general investigation of the study area by carrying out observations, sampling and in-situ measurements of each borehole, as well as the good conservation of the samples taken in a cooler. The various measurements that we took in-situ: pH, electrical conductivity, turbidity, salinity, temperature, and TDS were carried out by using a multi-parameter probe in the laboratory of appropriate methods such as titled-sorting, spectrophotometry, atomic absorption spectrometry, ArcGise and Excel software. With regard to the results from laboratory analysis (physical and chemical analysis), the parameters showed that the standards recommended by the WHO were not respected. We affirm that the water consumed in the Mitendi South-East district in Mont-Ngafula town ship is not drinkable. Since, it can cause several water-borne diseases. It would be better to treat that water before being drunk. .展开更多
A survey and evaluation was carried out on a potential granitoid quarry site in the locality of Linguésso (North West of Ivory Coast) with the aim of identifying and estimating the quantity of exploitable granite...A survey and evaluation was carried out on a potential granitoid quarry site in the locality of Linguésso (North West of Ivory Coast) with the aim of identifying and estimating the quantity of exploitable granite based on the electrical resistivity methods. The combination of electrical trailing, sounding and tomography techniques allowed the determination of the characteristics of the rock deposit, namely the electrical signature (between 19,259 Ωm and 86,316 Ωm), the extension (N90°), the rooting (between 0 and 45 m) and the fracturing (between N14° and N160°) of the granitic formation sought. The modeling resulted in an estimated mineable rock volume of 2,936,250 m<sup>3</sup> providing a production quantity of 7,927,875 tonnes.展开更多
The performance of industrial waste incineration bottom ash in controlled low-strength material （CLSM） was investigated in this paper, as the quarry dust was added. CLSM mixtures were made from the industrial waste ...The performance of industrial waste incineration bottom ash in controlled low-strength material （CLSM） was investigated in this paper, as the quarry dust was added. CLSM mixtures were made from the industrial waste incineration bottom ash, quarry dust, and cement. Tests for fresh density, bleeding, compressive strength, shear strength, hydraulic conductivity, and excavatability were carried out. The com- pressive strength ranges from 60 kPa to 6790 kPa, the friction angle varies from 5°to 19°, and the cohesion is from 4 to 604 kPa. Most of the mixtures are found to be non-excavatable. It is indicated that the quarry dust addition increases the compressive strength and shear parame- ters, decreases bleeding, and increases the removability modulus.展开更多
Extraction of Limestone is an economically important and widespread activity in Ghana and has existed since historical times. However, in spite of its remarkable contribution towards economic development, some adverse...Extraction of Limestone is an economically important and widespread activity in Ghana and has existed since historical times. However, in spite of its remarkable contribution towards economic development, some adverse impacts have been noticed, especially where extraction is carried out without proper planning and use of modern technology and scientific methods. We have carried out an assessment on the environmental effects of limestone quarrying on some communities in the Lower Manya Krobo District in the Eastern region of Ghana. Dust emission is one of the major effects of the practice of limestone extraction and as such, dust (PM10) sampling was conducted at the affected communities. Mean dry season results recorded in these communities stand at 125.0 μg/m3 or Bueryonye, 116.0 μg/m3 at Odugblase and 109.3 μg/m3 at Klo-Begoro. Oterkpolu community which served as the control recorded an average of 50.5 μg/m3. Average rainy season values recorded for the communities were 83.3 μg/m3 for Bueryonye, 113.1 μg/m3 at Odugblase and 74.4 μg/m3 at Klo-Begoro. The control community, Oterkpolu, had 43.3 μg/m3. These values are above the EPA, Ghana daily guideline level of 70 μg/m3 over a time-weighted average per 24 hours. Questionnaires administration and health records obtained from the health facilities in the communities revealed notable deteriorations in the health of the people as a result of the quarrying activities in the area. Notable among these is the prevalence of malaria though not related to dust emissions, it results from mosquitoes breeding in the stagnant pools of water found in pits created as a result of the mining activity. Other common health cases recorded were acute respiratory tract infection, ear and eye infections, cough and pneumonia.展开更多
Natural radionuclides content in granite from eight functional quarries in Osun State, Southwestern Nigeria was assessed. Eighty granite samples comprise?¾?inches.?½?inch and stone-dust were collec...Natural radionuclides content in granite from eight functional quarries in Osun State, Southwestern Nigeria was assessed. Eighty granite samples comprise?¾?inches.?½?inch and stone-dust were collected from Wolid, Slava, Ayofe, Espro, Ife/Modakeke, Krystal Vountein, Clario and Omidiran quarries in the State. Measurement was done using a high purity germanium (HPGe) detector. The statistical analysis was carried out using Statistical Package for Social Sciences (SPSS) software to determine if granite size has an impact on the activity concentrations. The results revealed that the mean activity concentrations of 238U (12.64 ± 1.89 Bq·kg -1) and 232Th (16.93 ± 2.46 Bq·kg -1) were highest in?¾?inch granite and lowest in stone-dust (5.01 ± 0.77 and 8.97 ± 1.37 Bq·kg -1 respectively), whereas 40K is highest in the ¾?inches (266.19 ± 35.53 Bq·kg -1) and lowest in?½?inches (151.85 ± 25.09 Bq·kg -1) granite. Espro has the highest (23.75 ± 3.74 Bq·kg -1) while Wolid has the lowest (4.11 ± 0.73 Bq·kg -1) 238U activity concentration and Slava has lowest for 232Th (8.21 ± 1.12 Bq·kg -1) and 40K (109.54 ± 11.06 Bq·kg -1). The radiological hazard parameters such as absorbed dose, annual effective dose radium equivalent, gamma index, external index, and internal index, were calculated to assess the radiation hazards associated with granite samples. The results obtained are lower than the recommended limits. The results were compared with the published data of other countries. Although, all the calculated radiation hazard indices were lower than the permissible limits. Therefore, people working in the quarries, granite end-users and the general public are safe from radiological health risks from the quarries, since there is no significant health hazard. The research will give reliable information on activity concentrations of natural radionuclides in granite rocks, contribute to a better understanding of radioactivity distribution in granite, and develop standards.展开更多
Through the study on landscape reconstruction of abandoned quarry pits in mountainous area of Jiangzhe District, it was pointed out that it was of not only practical significance but also ecological significance of su...Through the study on landscape reconstruction of abandoned quarry pits in mountainous area of Jiangzhe District, it was pointed out that it was of not only practical significance but also ecological significance of sustainable development to some extent, to scientifically and rationally rebuild and exploit abandoned quarry pits and to create new landscape, so that their landscape value and environmental benefit would entirely improve and that culture would be inherited and developed by making use of overt cultural fragments.展开更多
A quarry is a surface mining operated place, which produces enormous quantifies of gravel, limestone, and other materials for industrial and construction applications. Restoration and revegetation of deserted quarries...A quarry is a surface mining operated place, which produces enormous quantifies of gravel, limestone, and other materials for industrial and construction applications. Restoration and revegetation of deserted quarries are becoming increasingly important. Three areas of a typical quarry in South China： terrace for crushed materials （terrace）, spoiled mound, and remaining side slope, were investigated, to compare the existing plant species and to study the relationship between environmental factors and revegetation. The plant species composition of these three areas was found to differ significantly after eight years of natural recovery. The typical plant communities found over them were composed of gramineous herbs, ferns, and shrubs. Soil organic matter, soil moisture, and soil bulk density were considered to be the major determining factors for vegetation succession. There existed abiotic and biotic thresholds during quarrying restoration. Suggestions had been presented that could have accelerated the process of natural recovery in quarries.展开更多
The application of the non-explosive expansion material （NEEM） is widely used as the controlled fracture method in quarry min- ing, especially in hard rocks. The pressure of NEEM is an important parameter in causing...The application of the non-explosive expansion material （NEEM） is widely used as the controlled fracture method in quarry min- ing, especially in hard rocks. The pressure of NEEM is an important parameter in causing rock fracture. An empirical model based on hole spacing was developed to determine the pressure of NEEM in the rock fracture process. Primarily, the empirical model was developed by the mathematical method, utilizing dimensional analysis. Then, the Phase2 code, which is based on the finite element method, was utilized to predict crack growth in rocks. The results of numerical analysis show slight deviations from the empirical model. Hence, the polynomial re- gression analysis was used to modify the model. Finally, the modified model shows a good agreement with the results gained from numerical modeling.展开更多
Geophysical surveys are frequently applied in mining prospection to detect the presence and volume of ore bodies of different nature.Particularly,in gypsum ore bodies exploitation,electrical resistivity measurements a...Geophysical surveys are frequently applied in mining prospection to detect the presence and volume of ore bodies of different nature.Particularly,in gypsum ore bodies exploitation,electrical resistivity measurements are usually the most used methodology.However,it has been observed that different electrical resistivity values can be obtained depending on geometrical features and composition of gypsum.Indeed,electrical resistivity of gypsum rocks depends on several parameters,such as gypsum purity,nature of secondary minerals,porosity,saturation and interstitial fluid properties.Saturation and hydrogeological setting,in particular,were recognized as the most influencing parameters.Hydrogeological conditions of gypsum rock masses are also very relevant for exploitability,safety conditions and economic feasibility and should be accurately known during the prospection and planning phases of the quarries.In this work,a relationship between electrical resistivity and saturation degree of gypsum is proposed.The possibility to estimate gypsum porosity with the use of this relationship is also investigated.The reliability of laboratory measurements is finally verified in comparison with field and modelled resistivity data.The reported results underline the potentiality of the proposed approach to obtain a reliable characterization of the studied ore body.展开更多
The aim of this study is to create alternative approaches to predict human response to ground vibration.Site measurements were conducted in an urban quarry.The multiple discriminant analysis technique was used to deve...The aim of this study is to create alternative approaches to predict human response to ground vibration.Site measurements were conducted in an urban quarry.The multiple discriminant analysis technique was used to develop classification models.The measured ground vibration values were grouped based on the limit values appearing in the literature.Two classification models were created to predict human response to ground vibration.In addition,classical predictor equations were developed to compare to the classification models.The best equations were chosen considering several error measures.All the models were tested on the independent data.The prediction accuracy of the discriminant analysis models is quite promising.Nearly eighty-nine percent of the test data were correctly classified.The classification models have a combined structure.The results of the models can be directly presented to the neighbors of the studied quarry.The models are not complex.They do not require additional software or information to practice and can be easily used by site engineers.展开更多
The improvement of the soil physical and chemical properties is the most important foundation for mine ecological restoration.The experiment is aimed at undisturbed area,restored area,and damaged area of abandoned Yon...The improvement of the soil physical and chemical properties is the most important foundation for mine ecological restoration.The experiment is aimed at undisturbed area,restored area,and damaged area of abandoned Yongledian Quarry in Beijing.Through determination and analysis of soil physical and chemical properties,it shows that there are significant differences in the composite effects of soil physical and chemical properties between restored area,and undisturbed area,damaged area,and engineering restoration effectively improves the composite effects of soil physical and chemical properties in the restored area.The single factor hypothesis test shows that soil pH value,organic matter,alkali-hydrolyzable nitrogen,and total nitrogen traits are the key targets to be restored in this mining area.展开更多
文摘The framing of this theme would contribute to a better analysis of the benefits of open-air quarrying in Zinder, and should make it possible to understand and measure the socio-environmental externalities of this type of activity in an urban environment. The approach method consisted of carrying out surveys combined with field observations and interviews with the various stakeholders as well as the local population. The results obtained made it possible to identify both positive and negative impacts. The positive impacts are above all the advantages derived from these aggregate quarries, in particular, the creation of direct and permanent jobs and the increase in community income. The price of piling up a truck costs around 28,000 CFA ($56 CAN) and that of loading is around 10,000 F CFA ($20 CAN). This has the effect of removing young people (20 - 39 years old) from the circuit of migration outside the region and even the country. The possibility of using the extraction sites by the local population was identified, in terms of profits relating to fish farming, off-season crops, animal drinking and reclaimed plots. The study also noted negative externalities, such as the temptation of young boys to become involved in extractive activities for immediate gains at the expense of school attendance. Added to this is the upheaval in the topography of the urban landscape, pollution and nuisances (noise, visual and olfactory), while the disappearance or clogging of quarry ponds is the cause of frequent flooding in the neighborhoods. In short, corrective measures (e.g. the revegetation of sites) certainly make it possible to minimize the harmful impacts on the urban environment. But, to improve the performance and organizational capacity of the quarrying industry in Niger, even stronger regulation, training and awareness of stakeholders prove to be the necessary measures.
文摘Quarrying is an activity contributing to the vitality of the Moroccan economy. However, most of these quarries were abandoned at the end of extraction and became dump and later a place of uncontrolled landfills. The number of restored or rehabilitated quarries is limited and this threatens several aspects of the environment, especially, the quality of surface and ground water, landscape, forests, etc. This also gives rise to increased erosion risk. The study identifies plant species covering 10 abandoned quarries in the region of Rabat, especially the Bouregreg River and its affluent Akreuch in order to define a strategy for their restoration or rehabilitation. Field surveys were led to locate and map 10 abandoned quarries and to sample plant species. Herbaria were established and species were identified and classified. The results of the study distinguished 46 different plant species spread over 45 genera and 27 botanical families. The most dominant family in the quarries visited is Asteraceae. These results will allow us to study the vegetation dynamics in these abandoned lands and serve as a basis, in the selection of appropriate species in eventual restoration or rehabilitation projects.
文摘The I48TN is one of the 60 International Monitoring System (IMS) stations of the Comprehensive nuclear Test Ban Treaty Organization (CTBTO), characterized by its location in the heart of the IMS Infrasound network. The ability of the International Monitoring System (IMS) infrasound network to detect atmospheric nuclear explosions and other signals of interest is strongly dependent on station-specific ambient noise. This ambient noise, includes both incoherent wind noise and real coherent infrasonic waves. Infrasound analysis software detects tens to hundreds of events per day which consume a lot of time for the Infrasound analysts, to define and categorize events where around 90% of the detections are coherent noise. This study analyzed the importance of the synergy between infrasound and seismic data, and provided the infrasound data analyst with the most important local coherent infrasound sources in the region as recorded by the IMS station I48TN, in order to reduce the workload of the analysts and give them a clear view on the coherent noise affecting this station for better discrimination between events of interest like nuclear explosions and coherent sources. DTK_GPMCC and DIVA software were used to perform this study. Geotool software from the International Data Centre (IDC) was used in analysing seismic data from the Tunisian IMS station KEST. The result of this study allowed the characterization of the most important coherent local infrasound sources (Mines and Quarries) which are considered as coherent noise to I48TN station and correct parameters in some reference events in the Reference Event Database source of the International Data Centre.
文摘The management of overburden is an important task in open pit exploitations. Site topography and morphology as well as geological and geotechnical properties of natural and remoulded materials are the most important factors affecting the disposal phase. Economic and environmental requirements must be followed in order to achieve the best reclamation results, keeping into account site constraints such as slope stability, hauling and dumping issues, and interactions with groundwater. This paper deals with the above mentioned issues, illustrating a rational approach applied on the case of a large limestone quarry where the thickness of the overburden is relevant and the spoil material has to be dumped in a flooded pit. The proposed multidisciplinary approach led to the selection of most suitable methods for excavation, transportation and disposal. The selection was based on a detailed laboratory and site characterisation that defined favorable and adverse factors to be considered during the preliminary study of a large quarrying project.
文摘The main objective of this study is to determine the rates of vertically and horizontally oriented drilling processes in marble quarries and to observe the factors affecting the drilling rates in terms of physical and mechanical properties of the rocks. In situ drilling tests were performed in different marble quarries with different marble types and drilling times and penetration rates for a series of successive depthincrements were trying to be determined under vertically and horizontally oriented conditions. In order to understand the relation between the parameters that are investigated within the scope of this research, uniaxial compressive strength, Brazilian tensile strength, impact strength, Bohme abrasion strength, P-wave velocity, porosity, unit volume weight, Schmidt hardness index and brittleness index values were correlated with the drilling rates. It was noticed that the porosity and unit volume weight could be taken as the key parameters among them for obtaining meaningful correlation with drilling performance. It was also observed that the physical and mechanical rock properties are more relevant in vertical drilling than horizontal drilling.
文摘The study aimed at assessing the distribution and composition of dust produced at Pomona Stone Quarry mine in Harare, Zimbabwe. The source contribution to ambient PM2.5 and PM10 dust levels were quantified and their spatial distribution from the quarry to the receptor (community). The study also analysed the pH of soils around the mine, SiO2 and Al2O3 levels in quarry dust. Data was collected through direct observations, personal communications, experiments, soil and dust sampling and analyses. Dust sampling was done in January, April and August, to assess the effect of meteorological conditions on dust concentrations in two phases. Phase 1 was conducted during plant shut down (baseline measurements) while phase 2 was carried out during full plant operations (normal operating conditions), to assess the effect of quarry operations on the surrounding areas. Within the quarry production processes, crushing stage was the most dust emitting stage. Phase 1 dust results showed that both respirable (PM2.5) and inhalable (PM10) dust at all stages were below the legal limit, thus below 35 mg/m3 (respirable) and 180 mg/m3 (inhalable). Highest dust levels (209.9 mg/m3 inhalable and 69.01 mg/m3 respirable) were recorded in August, followed by April (206.9 mg/m3 inhalable and 67.52 mg/m3 respirable) then January (206.82 mg/m3 inhalable and 65.27 mg/m3 respirable). At all stages, highest dust concentrations for both parameters were recorded near the plant and decreased with increasing distance from the plant ( ranging from 209.9 mg/m3 - 19.41 mg/m3 inhalable and 69.01 mg/m3 - 14.23 mg/m3 respirable). This was attributed to the effect of particle size. August recorded the biggest area for both parameters falling within the non-permissible category, followed by April then January. The findings also revealed that the quarry dust contained higher levels of SiO2 (0.752 mg/cm3) which were 7 times higher than the recommended 0.1 mg/cm3 (NSSA). Low Al2O3 levels of 0.102 mg/cm3 were recorded and this was considered as environmentally safe. Soils were slightly acidic-alkaline and the t-test results at 95% confidence interval showed no significant difference between the results from site A and B (p = 0.526). It was concluded that quarry dust from Pomona had no significant effects on soil pH but possible health impacts on the receiving community. The study recommended that dust suppression systems such as water sprays, vegetation, air nets and enclosed production process must be implemented to curb dust emissions.
文摘The paper presents a new method for preventing dust pollution in stone quarries using naphthenic wastes of petroleum refineries. The method is based on the use of naphthenate solutions of metals as wetting agents to minimize dust release during stone-cutting process. The studies were carried out in one of the stone quarries of the Absheron peninsula. Initial experiments were conducted by using sodium-naphthenate (RCOONa) solution from alkali wastes of refineries. The results have shown that the use of RCOONa as wetting agent considerably reduces both dust pollution and energy consumption of the used equipment, while increasing the service life of stone-cutting saw. A series of researches were carried out with cupric naphthenate (RCOOCu) to further use the obtained dust-naphthenate mixture in agriculture. The effect of various parameters on the quality of the obtained product was investigated. The investigations have revealed that maximal dust reduction and the good quality of dust-naphthenate mixture were observed with 0.13% solution of RCOOCu at 11° - 13° angle of slope and 100 - 180 rotation∕min. intensity of conveyer.
文摘Geochemical investigation of the soils around quarry and barite mine sites in part of Akamkpa and Biase area of Southeastern Nigeria, was carried out to assess the concentration and enrichment levels of some heavy metals and trace elements in the soils. The investigation involved the collection of fifteen (15) soil samples between the depth of 15 - 30 cm. The samples were dried at room temperature, prepared and analyzed for heavy metals using inductively couple plasma mass spectrometer. The result shows that the concentration of Co, Cr, Nb, Pb and Sn were higher than the average shale values around the quarries while Ba, Pb and Sn were higher around the barite mines. The contamination factor indicates low to minimal contamination and low to considerable contamination around the quarries and barite mines respectively. While the Enrichment factor indicates minimal to significant enrichment around the quarries and minimal to extremely high enrichments around the barite mines. The result of the factor analysis and spatial distribution of the heavy metals suggests that the metal concentration and enrichment were controlled by the rock types, weathering and anthropogenic activities around the mine sites.
文摘The competition between coral and algae in marine reefs is pervasive through geologic time;that competition determines the structure and composition of reef communities, which we see in the fossil record. However, the relationships between coral and calcareous algae in reefs are poorly understood. To study this relationship, several hand samples and thin sections were examined from nine different foralgal reef localities around the world. Foralgal reefs typically extend from about 20 m depth or shallower on the seaward side of the reef. The first section is Salt Mountain, Alabama, which preserves a Paleocene reef. It contains a high percentage of red coralline algae with benthic foraminifera. The second section is IDOP-U1376, IIA Limestone, it is Middle Eocene, in the form of an isolated reef sandwiched between two igneous beds. The third section is the Utoe’ Limestone, New Caledonia, it is Middle Eocene in age and is composed mainly of grain-boundstone units with some igneous interlayered. The fourth section is the Darnah Formation in the West-Darnah roadcut section, Northeast Libya, it is Middle Eocene in age, it is composed of highly fossiliferous limestone (corals, red coralline algae, echinoids, mollusks, foraminifers, and bryozoans). The fifth section, the Al Bayda Formation (Algal Limestone Member) in Northeast Libya, is in the Drayanah—Al Abyar roadcut, Northeast Libya, it has several species of algae but also includes a high percentage of buildups of coral species. The sixth section is the Oligo-Miocene Al Faidiyah Formation (Al Fatayah Cement Quarry) limestone unit in Northeast Libya. The seventh section is (Core-core 20) late-early to middle Miocene Limestone Unit-Cicuco Field, NW Colombia. The eighth section is the Benghazi Formation at Benghazi Cement Quarry, in Northeast Libya, it is fossiliferous limestone, consisting of coral, algae, mollusks, and echinoids. The ninth and tenth sections are Quaternary reefs in the Bahamas and the Florida Keys, respectively. These reefs contain a high percentage of coral, red coralline algae, echinoids, mollusks, foraminifers, and ostracods. Based on the data and static analysis results on the thin sections and hand specimens, this study determines the occurrence and outcomes of coral-algal interactions among different coral growth forms (branching, upright, massive, encrusting, plating, and solitary). The Early Paleogene (Paleocene to Eocene) has the highest percentage of algae in two forms (crustose and frondose), which is a good indicator of a warm climate. In the Middle Eocene to Late Eocene, coral replaced algae in different localities in sections of that age. This change is an indicator of climatic cooling, especially in the western Lutetian Darnah section. In the Oligocene time, high-branching corals became abundant and escaped competition with the algae due to Icehouse conditions, as shown in the Al Bayda Formation. In the Miocene, coral species started to decline because of the return to Greenhouse conditions. Coral can lose its competitive edge when chemical and physical defense systems reduce growth and production due to warming. On the other hand, crustose-form algae attract the larvae of the coral. Algae induce them to get a more highly competitive frondose form, which is useful for corals as they decrease growth and production. Algae can quickly colonize the dead reef by using the firm substrate to rebuild themselves. This research may prove valuable when predicting the response of modern coral reef systems to future climatic warming conditions and provides a model for what future reefs may look like.
文摘The exploitation of groundwater by drilling in the Mitendi South-East district constitutes a solution to the water shortage in this peripheral part of the Mont-Ngafula township in Kinshasa, the capital of the DR Congo. Individuals exploit groundwater in boreholes to serve the population without taking into account certain necessary aspects such as the origin of the groundwater table and the quality which constitute the major problems of this work such as: What is the quantity of water from the recharge of our aquifer? What is the state of the Mitendi South-East aquifer water in relation to some physico-chemical parameters? The cardinal objective of this work is to provide chemical data and trace elements in each analyzed borehole and determine the type of recharge of the underground aquifer. The specific objectives are as follows: analyze the potability of groundwater on a physico-chemical level and their chemical facies, take the geographical coordinates of water samples from the aquifer in each targeted borehole in order to develop the sampling map of the area under study;also check each parameter analyzed in relation to WHO standards. We carried out a general investigation of the study area by carrying out observations, sampling and in-situ measurements of each borehole, as well as the good conservation of the samples taken in a cooler. The various measurements that we took in-situ: pH, electrical conductivity, turbidity, salinity, temperature, and TDS were carried out by using a multi-parameter probe in the laboratory of appropriate methods such as titled-sorting, spectrophotometry, atomic absorption spectrometry, ArcGise and Excel software. With regard to the results from laboratory analysis (physical and chemical analysis), the parameters showed that the standards recommended by the WHO were not respected. We affirm that the water consumed in the Mitendi South-East district in Mont-Ngafula town ship is not drinkable. Since, it can cause several water-borne diseases. It would be better to treat that water before being drunk. .
文摘A survey and evaluation was carried out on a potential granitoid quarry site in the locality of Linguésso (North West of Ivory Coast) with the aim of identifying and estimating the quantity of exploitable granite based on the electrical resistivity methods. The combination of electrical trailing, sounding and tomography techniques allowed the determination of the characteristics of the rock deposit, namely the electrical signature (between 19,259 Ωm and 86,316 Ωm), the extension (N90°), the rooting (between 0 and 45 m) and the fracturing (between N14° and N160°) of the granitic formation sought. The modeling resulted in an estimated mineable rock volume of 2,936,250 m<sup>3</sup> providing a production quantity of 7,927,875 tonnes.
基金the Ministry of Science, Technology and Innovation (MOSTI), Government of Malaysia and University of Malaya for providing the funds to support this research work
文摘The performance of industrial waste incineration bottom ash in controlled low-strength material （CLSM） was investigated in this paper, as the quarry dust was added. CLSM mixtures were made from the industrial waste incineration bottom ash, quarry dust, and cement. Tests for fresh density, bleeding, compressive strength, shear strength, hydraulic conductivity, and excavatability were carried out. The com- pressive strength ranges from 60 kPa to 6790 kPa, the friction angle varies from 5°to 19°, and the cohesion is from 4 to 604 kPa. Most of the mixtures are found to be non-excavatable. It is indicated that the quarry dust addition increases the compressive strength and shear parame- ters, decreases bleeding, and increases the removability modulus.
文摘Extraction of Limestone is an economically important and widespread activity in Ghana and has existed since historical times. However, in spite of its remarkable contribution towards economic development, some adverse impacts have been noticed, especially where extraction is carried out without proper planning and use of modern technology and scientific methods. We have carried out an assessment on the environmental effects of limestone quarrying on some communities in the Lower Manya Krobo District in the Eastern region of Ghana. Dust emission is one of the major effects of the practice of limestone extraction and as such, dust (PM10) sampling was conducted at the affected communities. Mean dry season results recorded in these communities stand at 125.0 μg/m3 or Bueryonye, 116.0 μg/m3 at Odugblase and 109.3 μg/m3 at Klo-Begoro. Oterkpolu community which served as the control recorded an average of 50.5 μg/m3. Average rainy season values recorded for the communities were 83.3 μg/m3 for Bueryonye, 113.1 μg/m3 at Odugblase and 74.4 μg/m3 at Klo-Begoro. The control community, Oterkpolu, had 43.3 μg/m3. These values are above the EPA, Ghana daily guideline level of 70 μg/m3 over a time-weighted average per 24 hours. Questionnaires administration and health records obtained from the health facilities in the communities revealed notable deteriorations in the health of the people as a result of the quarrying activities in the area. Notable among these is the prevalence of malaria though not related to dust emissions, it results from mosquitoes breeding in the stagnant pools of water found in pits created as a result of the mining activity. Other common health cases recorded were acute respiratory tract infection, ear and eye infections, cough and pneumonia.
文摘Natural radionuclides content in granite from eight functional quarries in Osun State, Southwestern Nigeria was assessed. Eighty granite samples comprise?¾?inches.?½?inch and stone-dust were collected from Wolid, Slava, Ayofe, Espro, Ife/Modakeke, Krystal Vountein, Clario and Omidiran quarries in the State. Measurement was done using a high purity germanium (HPGe) detector. The statistical analysis was carried out using Statistical Package for Social Sciences (SPSS) software to determine if granite size has an impact on the activity concentrations. The results revealed that the mean activity concentrations of 238U (12.64 ± 1.89 Bq·kg -1) and 232Th (16.93 ± 2.46 Bq·kg -1) were highest in?¾?inch granite and lowest in stone-dust (5.01 ± 0.77 and 8.97 ± 1.37 Bq·kg -1 respectively), whereas 40K is highest in the ¾?inches (266.19 ± 35.53 Bq·kg -1) and lowest in?½?inches (151.85 ± 25.09 Bq·kg -1) granite. Espro has the highest (23.75 ± 3.74 Bq·kg -1) while Wolid has the lowest (4.11 ± 0.73 Bq·kg -1) 238U activity concentration and Slava has lowest for 232Th (8.21 ± 1.12 Bq·kg -1) and 40K (109.54 ± 11.06 Bq·kg -1). The radiological hazard parameters such as absorbed dose, annual effective dose radium equivalent, gamma index, external index, and internal index, were calculated to assess the radiation hazards associated with granite samples. The results obtained are lower than the recommended limits. The results were compared with the published data of other countries. Although, all the calculated radiation hazard indices were lower than the permissible limits. Therefore, people working in the quarries, granite end-users and the general public are safe from radiological health risks from the quarries, since there is no significant health hazard. The research will give reliable information on activity concentrations of natural radionuclides in granite rocks, contribute to a better understanding of radioactivity distribution in granite, and develop standards.
文摘Through the study on landscape reconstruction of abandoned quarry pits in mountainous area of Jiangzhe District, it was pointed out that it was of not only practical significance but also ecological significance of sustainable development to some extent, to scientifically and rationally rebuild and exploit abandoned quarry pits and to create new landscape, so that their landscape value and environmental benefit would entirely improve and that culture would be inherited and developed by making use of overt cultural fragments.
文摘A quarry is a surface mining operated place, which produces enormous quantifies of gravel, limestone, and other materials for industrial and construction applications. Restoration and revegetation of deserted quarries are becoming increasingly important. Three areas of a typical quarry in South China： terrace for crushed materials （terrace）, spoiled mound, and remaining side slope, were investigated, to compare the existing plant species and to study the relationship between environmental factors and revegetation. The plant species composition of these three areas was found to differ significantly after eight years of natural recovery. The typical plant communities found over them were composed of gramineous herbs, ferns, and shrubs. Soil organic matter, soil moisture, and soil bulk density were considered to be the major determining factors for vegetation succession. There existed abiotic and biotic thresholds during quarrying restoration. Suggestions had been presented that could have accelerated the process of natural recovery in quarries.
文摘The application of the non-explosive expansion material （NEEM） is widely used as the controlled fracture method in quarry min- ing, especially in hard rocks. The pressure of NEEM is an important parameter in causing rock fracture. An empirical model based on hole spacing was developed to determine the pressure of NEEM in the rock fracture process. Primarily, the empirical model was developed by the mathematical method, utilizing dimensional analysis. Then, the Phase2 code, which is based on the finite element method, was utilized to predict crack growth in rocks. The results of numerical analysis show slight deviations from the empirical model. Hence, the polynomial re- gression analysis was used to modify the model. Finally, the modified model shows a good agreement with the results gained from numerical modeling.
文摘Geophysical surveys are frequently applied in mining prospection to detect the presence and volume of ore bodies of different nature.Particularly,in gypsum ore bodies exploitation,electrical resistivity measurements are usually the most used methodology.However,it has been observed that different electrical resistivity values can be obtained depending on geometrical features and composition of gypsum.Indeed,electrical resistivity of gypsum rocks depends on several parameters,such as gypsum purity,nature of secondary minerals,porosity,saturation and interstitial fluid properties.Saturation and hydrogeological setting,in particular,were recognized as the most influencing parameters.Hydrogeological conditions of gypsum rock masses are also very relevant for exploitability,safety conditions and economic feasibility and should be accurately known during the prospection and planning phases of the quarries.In this work,a relationship between electrical resistivity and saturation degree of gypsum is proposed.The possibility to estimate gypsum porosity with the use of this relationship is also investigated.The reliability of laboratory measurements is finally verified in comparison with field and modelled resistivity data.The reported results underline the potentiality of the proposed approach to obtain a reliable characterization of the studied ore body.
基金Research Fund of the Istanbul Technical University under Grant No.MGA-2017-40581the Scientific and Technological Research Council of Turkey-TUBITAK-under Grant No.217M071。
文摘The aim of this study is to create alternative approaches to predict human response to ground vibration.Site measurements were conducted in an urban quarry.The multiple discriminant analysis technique was used to develop classification models.The measured ground vibration values were grouped based on the limit values appearing in the literature.Two classification models were created to predict human response to ground vibration.In addition,classical predictor equations were developed to compare to the classification models.The best equations were chosen considering several error measures.All the models were tested on the independent data.The prediction accuracy of the discriminant analysis models is quite promising.Nearly eighty-nine percent of the test data were correctly classified.The classification models have a combined structure.The results of the models can be directly presented to the neighbors of the studied quarry.The models are not complex.They do not require additional software or information to practice and can be easily used by site engineers.
文摘The improvement of the soil physical and chemical properties is the most important foundation for mine ecological restoration.The experiment is aimed at undisturbed area,restored area,and damaged area of abandoned Yongledian Quarry in Beijing.Through determination and analysis of soil physical and chemical properties,it shows that there are significant differences in the composite effects of soil physical and chemical properties between restored area,and undisturbed area,damaged area,and engineering restoration effectively improves the composite effects of soil physical and chemical properties in the restored area.The single factor hypothesis test shows that soil pH value,organic matter,alkali-hydrolyzable nitrogen,and total nitrogen traits are the key targets to be restored in this mining area.
