Mineral Exploration Activities Research Articles

Geochronology and geochemistry of granites from the Longhua Ni-Co deposit, South China: Implication for the formation of Ni-Co mineralization

Mineral exploration activities since 2010 in a previously poorly explored region of northeastern Guangxi province, South China, confirmed the existence of a potentially large hydrothermal Ni-Co deposit. As a newly discovered deposit, many aspects of this deposit are still unclear, including in which tectonic setting the deposit formed and how the high-grade mineralization developed. To address these questions, in this study, we conduct a comprehensively geochronological and geochemical study on the Dajin pluton (consisting of biotite monzogranite and sericitized monzogranite), which is the only pluton occurring in the district. LA-ICP-MS zircon U-Pb dating shows that two types of granites were emplaced nearly at the same time, with biotite monzogranite and sericitized monzogranite being 449 ± 15 Ma and 448.4 ± 8.8 Ma, respectively. This, combined with previously published studies, confirms that the Dajin pluton was broadly emplaced during the formation of the Longhua deposit. These granites are characterized by high K2O, and noticeable depletion of Eu, Sr, P and Ti, with whole-rock εNd(t) values ranging from −1.99 to −4.26 and zircon εHf(t) values ranging from −0.9 to 4.1. These features support that the studied granites are typical of A2-type granites, which experienced strong fractional crystallization and formed in a post-collisional environment. Although Co and Ni might not have been originally derived from granitic magmas, we suggest that the emplacement of the Dajin pluton facilitated the formation of high-grade Ni-Co mineralization in two ways: (1) melting the Co– and Ni-enriched mafic basement probably existing in the deep crust, and (2) remobilizing and concentrating metals from wall rocks.

National-scale Geochemical Survey: Distribution of chemical elements in stream sediment of South and Central Asia

This work was carried out as the Pakistani, Uzbekistani, Tajikistani, and Kyrgyzstani contribution to the National-scale Geochemical Survey of South and Central Asia (NGSSCA) project, the objective of which was to document and study the amounts and distribution of chemical elements in stream sediment of South and Central Asia where such national-scale geochemical mapping is launched for the first time. In the framework of the NGSSCA project deployed in Pakistan, Uzbekistan, Tajikistan, and Kyrgyzstan, 9237 stream sediment samples (<2 mm grain-size fraction in alpine desert and mountainous area) were collected at an average density of 1 sample site/100 km2, on the basis of a common stream sediment sampling protocol. The resultant compositional data sets and cartographic products will vastly benefit future mineral exploration activity, surficial (and even solid Earth) geochemical processes studies (e.g., chemical weathering), and environmental evaluation. Eight elements of economic interests (e.g., Ag, Sb, W, Mo, Li, Be, Cu, and Co) are selected to demonstrate their distribution pattern in stream sediment and the main controlling factors. It's concluded that the anomalies for the selected elements in the NGSSCA project can thus be directly linked to different geogenic sources, e.g., underlying bedrock, soil type, mineralization or ore deposits, and large-scale fault systems. Based on the results and the integrated anomaly maps, some new target areas for the corresponding metallic mineralization are predicted, which will provide a basis for further mineral exploration.

Sea Bed Mining

The seabed is surely one of the last mining frontiers on earth remaining for mankind, to extract economic mineral deposits. It is hence imperative that India with its Obvious Geological Potential (OGP) area on the land surface amounting to 0.57 million km, for which baseline geoscience data has been generated and mineral exploration activities are ongoing, needs to be supplemented with mineral wealth on our sea beds, within our Territorial Waters (TW) and Exclusive Economic Zone (EEZ). Studies by the Geological Survey of India (GSI) and other agencies for mineralized horizons in the terrestrial OGP areas have been a continuous process. The baseline geoscience and mineral exploration data are published regularly by GSI and Indian Bureau of Mines (IBM) and made available to respective stakeholders. India has a 2.02 million km area under its TW and EEZ. Our East and West Coasts of the Peninsular India are endowed with phosphate, manganese nodules, lime mud and monazite sands with rare earth elements (REE) and thorium that have been surveyed by the Marine and Coastal Survey Division (MCSD) of the GSI with their research vessels to establish the potentiality. According to the data available, 1,53,996 million tons of lime mud within the EEZ off Gujarat and Maharashtra coasts, 745 million tons of construction grade sand, off Kerala coast, 79 million tons of heavy mineral placers in the inner-shelf and mid-shelf, off Odisha, Andhra Pradesh, Kerala, Tamil Nadu and Maharashtra, phosphorite in the Eastern and Western continental margins, polymetallic ferromanganese nodules and crusts in Andaman Sea and Lakshadweep Sea have been reported. The CSIR- National Institute of Oceanography has been embarking on research for seabed mineral deposits. The Offshore Areas Mineral (Development and Regulation) Amendment Bill, 2023, passed by Lok Sabha on 01.08.2023, has amendments to the Offshore Areas Mineral (Development and Regulation) Act, 2002, OAMDR Act (Ministry of Mines, Govt. of India, 2002). It envisages major initiatives to allow auction of mineral blocks 45° X 45° (latitude and longitude) in respect of any mineral or prescribed group of associated minerals, under one or more operating rights (taken together). The Act has a provision for setting up of a non-lapsable Offshore Areas Mineral Trust to maintain a fund under the Public Account of India. This fund will be financed by a yet to be determined, additional levy on the production of offshore minerals that will be used for exploration, research, disaster relief and for mitigation of adverse impacts of seabed mining. We have the National Exploration Trust and the District Mineral Foundation Trust funds, to which royalties are paid by stakeholders for onshore mining.

Soil Survey and Lithogeochemical Techniques in Mineral Exploration

This paper investigates the critical roles of soil surveys and lithologic evaluation in identifying potential mineral resources. Soil surveys involve the systematic mapping, examination, description, and classification of soils within a defined area. Through targeted sampling and laboratory analysis, these surveys can reveal the concentration of metals in the soil. By analyzing these metal signatures, geoscientists can infer the underlying geology and identify areas with a higher likelihood of hosting valuable mineral deposits. Lithologic evaluation complements soil surveys by focusing on the physical characteristics of rock units exposed at outcrops, in hand samples, or cores. Observable with the naked eye or a magnifying lens, these characteristics include color, texture, and structural features. Lithogeochemistry, or rock geochemistry, builds upon this foundation by analyzing the chemical composition of the bedrock. This analysis aims to identify spatial patterns of elements typically associated with specific types of mineral deposits. By integrating the findings from soil surveys and lithologic evaluations, geoscientists gain a comprehensive understanding of the subsurface environment, enabling them to prioritize areas for further mineral exploration activities. This paper delves into the fundamentals of these techniques, highlighting their strengths and limitations in the context of mineral resource exploration.

Human health risk assessment of air pollutants in the largest coal mining area in Brazil.

The Candiota region, located in the extreme south of Brazil, has the largest mineral coal deposit in the country, and this activity is capable of releasing pollutants in which they are associated with the contamination of different matrices (soil, water, and air). The present study aimed to carry out a risk assessment to human health of atmospheric pollutants NO2 and SO2 and PM10-bound metal(loid)s in the municipality of Candiota, in addition to evaluating the correlation of meteorological parameters for the dynamics and potential risk of these pollutants. Pollutants were sampled from stations located almost 4km from coal exploration activities, and the trace elements As, Cd, Se, Pb, and Ni, in addition to NO2 and SO2, were evaluated. Risk assessment was conducted taking into account the risk to adults via the inhalation route. During the sampling period, all pollutants presented values lower than national legislation or internationally accepted values, and Pb was the element that presented the highest values throughout the sampled period. The risk assessment showed no carcinogenic and non-carcinogenic risks, even when considering the sum of the risk of all analyzed pollutants. It can be observed that the highest levels of Pb, As, and Se occurred in the winter season, while the levels of Ni and Cd were higher in the spring, and the meteorological parameters were correlated with the pollutants, even using a temporal lag of 5days. Although the air pollutants evaluated did not present a risk to human health, continuous monitoring of regions with strong mineral exploration activity must be carried out with a view to maintaining the well-being of exposed populations, mainly because there are people living in areas closer to sources of coal pollution than distance to air quality monitoring stations.

Analysis of Transient Characteristics of Induced Polarization in Innovative Mineral Exploration Solutions (from Case Studies of Gold Deposits)

Abstract—The paper discusses current state of the spectral approach to analysis of induced polarization (IP), its possibilities and limitations, along with directions for the method development. Reviewed are the main methods and approaches for estimation of spectral IP parameters and their specific features. Our practical experiments have shown the advantages of analysis of transient IP characteristics over standard approaches to the IP data analysis and processing. Results of the standard and spectral approaches application to analysis of IP data when solving mineral exploration problems at the Maletoyvayam gold deposit (Kamchatka Peninsula) and the Yasnoe gold occurrence (Taimyr Peninsula) are compared. Here, we demonstrate that low efficiency of works is erroneously regarded as one of the main factors hindering a broad adoption of the spectral IP method in mineral exploration activities. Rather, it is a lack of automated techniques for analysis of transient IP characteristics. We propose a new approach to spectral analysis of IP data, based on the algorithms for image recognition of a reference object, and describe pioneering efforts of its practical application.

Karstic Limestone Outcrops Harbor High Bat Diversity in a Deeply Anthropized Landscape in Southeastern Brazil

The availability of shelter in karst areas affects the richness, abundance, and assemblage composition of bat species and may play an important role in movement dynamics, activity patterns, and foraging behavior. Our work in the midwestern region in the state of Minas Gerais, southeastern Brazil, showed a high richness of the bat fauna, given the anthropic impact caused by mineral exploration and agricultural activities, thus leaving vegetation islands over karst areas in a vast anthropized matrix. Sampling at 12 sites resulted in 1,444 captures of bats, representing 30 species. Our beta diversity partitioning analyses indicated a pattern of turnover, i.e. species replacement, suggesting that these vegetation fragments may function as ecological springboards or stopping points.

Mineral Exploration Scenario in India: Prospect, Promise and Policy Reforms

Abstract India is endowed with unique geological and tectonic setting conducive to host potential mineral resources. A look at the mineral resource status of selected minerals in India indicates abundant and/or adequate resources of iron, chromite, manganese, bauxite, coal, limestone, dolomite, mica, zinc, graphite but deficient to scarce resources of nickel, cobalt, molybdenum, copper, sulphur, potash, apatite, rock phosphate, gold, PGE’s, diamond etc., in spite of the vast obvious geological potential (OGP) blocks that exist in India. The OGP blocks have been estimated to around 1 lakh Km2 for gold, 3 lakh Km2 for diamond, 1.6 lakh km2 for base metals, 8000 km2 for PGEs and 5000 km2 for iron ores. By a rough estimate only 10% of this is explored and less than 2% is mined. The Reserve to Resource ratio which, as per mineral exploration practice, should be over 50% is woefully low for most of the minerals. For instance it is 17% for bauxite, 14% for copper, 24% for iron 14% for lead-Zinc, 8% for limestone and 30% for chromite etc. This calls for highly focused exploration strategy at high confidence level. India need to take a leaf out of strategies of many other countries and frame her own policy based on OGP areas to trigger the mining growth by accelerating mineral exploration programme. Benefits that flow from the mineral exploration/mining sector have huge impact on local populace, industry especially mineral dependent industries, employment and overall prosperity. Recent amendments in the Mines and Minerals (Development and Regulations) Act-1957 in the year 2021, have sought to bring out the potential of the mineral sector such as to increase the revenue of the State, escalate employment, maintain the continuity of mining operation, increase production, time bound operationalization of mines, increase the speed of exploration and auction of mineral resources and lastly to resolve the long pending issues that have decelerated the growth of this sector. This is an encouraging step and likely to bear fruits. These legislative and policy reforms in the mineral exploration and mining sector have laid down a sustainable road map that aims to boost mineral output by 200% in the next 7 years and raise the GDP contribution to 2.5%. Mineral laws Amendments Act 2020 are transformative and investor friendly. Mining is now defined as legal entity and hence seamless transfer of mining lease is possible. New auction mechanism instituted will ensure transparency, eliminate discretion, reducing bureaucratic delay and easier trading of mineral rights. Setting up of District Mineral foundation (DMF) will work for the interest and benefit of mining related operations and overcome the local resistance to the mineral exploration and mining activities. The National Mineral Exploration Trust (NMET) will focus on extending more financial assistance to government and also the private sectors to augment advance technology and will surely give fillip to exploration initiatives. The paper deals with such ideas in relation to the required thrust in mineral exploration sector in Indian context.

Mineral prospectivity mapping: a potential technique for sustainable mineral exploration and mining activities – a case study using the copper deposits of the Tagmout basin, Morocco

Mineral prospectivity mapping (MPM) based on the principle of geometric mean was applied to stream sediment geochemical, fault density, and aeromagnetic data from Tagmout basin, Morocco to determine new areas for optimizing copper exploration. The application of a fuzzy operator using stream sediment data, factor analysis, and fault density map, allowed weights to be assigned to these parameters so that the MPM function can process them to indicate the most favorable zones of copper mineralization. The model's accuracy as evaluated using a normalized density index (Nd with value 1.22) shows the reliability of the method. The potential copper concentration areas represent 8.22% of the entire basin of which 30% are concentrated in the western portion of the basin and other significant areas are in the southwest and northeast portions. The results indicate that MPM is a powerful technique for planning exploration programs that aim for sustainable mining activities.

Translating a mineral systems model into continuous and data-driven targeting models: An example from the Dolatabad chromite district, southeastern Iran

The Dolatabad chromite district, a well-endowed mineralized tract located in SE Iran, hosts numerous podiform chromite deposits. Its favorable geological setting and known chromite endowment suggest that the district has good potential for the discovery of additional chromite mineralization. However, the processes that controlled the development and preservation of the chromite ores are poorly known. As such, a better understanding of the ore-forming processes will be critical for the success of future exploration activities in the Dolatabad chromite district. Recognition of these critical genetic processes and the mapping of their spatial expressions are the precursors to mineral prospectivity mapping (MPM) as well as any mineral exploration activities on the ground. This study adopted a mineral systems approach to MPM, which entailed the formulation of a probabilistic framework to the recognition of the critical genetic processes and translation of these processes to mappable evidence maps. Here, we developed three proxies, representing trap, deposition, and preservation processes, that were subjected to a range of weighting procedures, including continuous (i.e., fuzzy gamma, geometric average, and data-driven index overlay) and data-driven machine-learning (i.e., multilayer perceptron neural network and random forests) methods. The machine-learning procedures outperformed the continuous procedures, suggesting that the former approaches are more reliable in targeting mineralized zones. The targets delineated by random forest algorithm, the superior model generated in this study, predicted c. 71% of the known chromite mineralization in c. 6% of the study area.

Gold mining and development in Côte d’Ivoire: Trajectories, opportunities and oversights

Over the past four decades, many countries in sub-Saharan Africa have undergone different waves of mining sector reform in a bid to catalyse growth. The focus of these exercises has been mainly to attract foreign investment to develop and at times, rejuvenate, export-led large-scale mining and accompanying mineral exploration activity. This despite yielding disappointing improvements, developmentally and economically of the sector. Perhaps even more significantly, however, is that under reform, most of the region’s governments have overlooked the importance of formalising and supporting artisanal and small-scale mining (ASM), which, by comparison, has a much greater impact locally and in many instances, developmentally. This article contributes to the body of literature on mining sector reform in sub-Saharan Africa, focusing on the case of Côte d'Ivoire. Drawing on findings from an extended period of fieldwork, the article examines critically how a large scale mining bias in Côte d’Ivoire has contributed to the marginalization of ASM. Consistent with most analysis of mining sector reform in sub-Saharan Africa, in Côte d’Ivoire, the government has successfully established an attractive investment climate and put aside vast parcels of land for multinational companies while simultaneously neglecting the needs of artisanal and small-scale operators.

Depth migration with the near surface: A case study for mineral exploration in China

Seismic reflection data used in mineral exploration are usually of poor quality because of rough topography and small-scale heterogeneities. However, there is an increasing demand for accurate imaging processes that can obtain such data. Here, we have developed a practical rugged depth migration method based on the finite-difference one-way wave equation. It can be used to improve imaging quality when faced with rough topography and complex geologic features. First, synthetic data are used to illustrate the errors and problems that cause unsatisfactory imaging results. This is usually because no consideration is given to rough topography during conventional processing procedures. To address this, a depth migration method that begins with the rugged topography is introduced. It can be used to produce better images. Real data from mineral exploration activities in Fujian, China, are then used to demonstrate the practical use of this method. We also compare two computational processes: The first corrects the data back to the original surface and then builds a velocity model before conducting rugged depth migration; the second process involves performing rugged depth migration on processed data featuring a smoothed surface following short-wavelength static correction and residual correction. The imaging results indicate that the section obtained from the processed data has better quality. They also indicate that the imaging quality of the original surface is affected by the built velocity model, which cannot include near-surface and small-scale structures.

Mineralogy, geochemistry and economic potentialities of heavy mineral sand resources of Bangladesh

Heavy mineral sand deposits are the important mineral resources of Bangladesh. Systematic mineral exploration activities carried out in the south eastern coastal belt of Bangladesh were successful to discover seventeen heavy mineral sand (HMS) deposits in the coastal beach and off-shore islands. Mineralogy, geochemistry and mineral processing characteristics of the heavy mineral sands and their economic potentialities are presented in the present paper. On an average, HMS deposits contain 23% total heavy minerals. In heavy fraction, average weight percentage of the economic minerals is: zircon 4.20%, rutile 2.04%, ilmenite 26.03%, garnet 6.45%, kyanite 3.92%, leucoxene 2.30%, magnetite 1.87% and monazite 0.31%; and the average weight percentage of other non-economic heavy minerals is 53.88%. Heavy mineral sand deposits altogether contain 1.76 million tons of economically important heavy minerals which are: limonite (1,025,000 tonnes), garnet (223,000 tons), zircon (158,000 tonnes), leucoxene (97,000 tons), kyanite (91,000 tons), rutile (70,000 tons), magnetite (81,000 tones) and monazite (17,000 tonnes). Occurrence of large amount of economic heavy minerals in the sand bars of Brahmaputra-Jamuna River has been reported by some recent studies. On an average, total heavy mineral percentage of the Brahmaputra-Jamuna sand bars is around 8.92%. Mineral sand processing on the bulk samples has been carried out at the pilot plant comprising gravity, magnetic and electrostatic separators to characterize the separation characteristics of individual economic heavy minerals. Geochemical studies on the separated heavy minerals show that TiO2 in rutile is around 90% and ZrO2 in zircon is around 65%, which are quite satisfactory in respect of commercial grade. Ilmenite contains low level of titanium dioxide (TiO2-43%) and higher level of chromium, manganese and iron. Beneficiation and upgrading of limonite will be required to make it a market able commodity. Valuable minerals present in the heavy mineral sand deposits of Bangladesh need to be mined sustainably and utilized for the benefit of the country.

Geophysical and Metalogenetic Modelling of the Copper Occurrence in Camaquã Sedimentary Basin, Brazilian Southern

The geophysics application is indicated procedure in mineral exploration activities, by the quickness and possible global reduction of project cost. This work presents the results of the DC resistivity and induced polarization methods joint application, integrated to geological and structural data from a potentially mineralized area with copper sulfides, located in the Northern border of the Camaqua Sedimentary Basin, Brazil Southern. The mineral occurrence is characterized by malachite and azurite impregnation on silicified Neoproterozoic metarenite outcrop of Passo da Promessa Formation (Marica Group). The geophysics acquisition consists in six electrical tomography lines in Schlumberger arrangement with 440 m each, the lines were separated on two groups disposed at orthogonal form where the center area is located the mineral occurrence in surface. The results indicate a low resistivity and high chargeability zone 60 m deep, related to a sulfided zone and surrounded by elevated resistivity, which point silicification areas. The structural analysis has revealed two main fracture systems in the crystalline basement (NE–SW and NW–SE), one in the metarenite (NE-SW) and fold with a N20 axis. The 3D visualization model reveals that the mineralization is oriented in the N125 direction (NW–SE). The NW–SE fracture family is secondary but is present in the occurrence area and coincident with the relaxing direction of the folding event. This context corroborates with the hypothesis of filling NW–SE fractures, result which indicates the relevance of this preferential direction in future mineral research campaigns in the Camaqua Basin.

Resources classification using fractal modelling in Eastern Kahang Cu-Mo porphyry deposit, Central Iran

Resources/reserves classification is crucial for block model creation utilised in mine planning and feasibility study. Selection of estimation methods is an essential part of mineral exploration and mining activities. In other word, resources classification is an issue for mining companies, investors, financial institutions and authorities, but it remains subject to some confusion. The aim of this paper is to determine a resources classification for a Cu block model generated by an Ordinary Kriging (OK) and a Concentration-Volume (C-V) fractal modelling based on estimated variance in Eastern Kahang Cu-Mo porphyry deposit, Central Iran. Variography, block modelling and cell declustering for dataset with respect to Cu concentrations as the main target in this deposit were conducted firstly. Then, Cu distribution model was carried out by the OK and estimated variances were calculated for all voxels. According to a C-V log-log plot, three populations for estimated variances were detected. ‘’Measured’’ resources contain voxels with estimated variances lower than 0.08 and more than 7 samples. Estimated variances varied between 0.08 and 0.24 in which more than 3 samples were engaged for estimation of ‘’Indicated’’ resources. ‘’Inferred’’ resources include estimated variances over 0.24 which are located in marginal parts of this deposit. Results derived via this study reveal that the C-V fractal modelling can be used for resources classification in different ore deposits.

Underground Vertical Seismic Profiling with Conventional and Fiber-Optic Systems for Exploration in the Kylylahti Polymetallic Mine, Eastern Finland

Seismic reflection methods have been used for the exploration of mineral resources for several decades. However, despite their unmatched spatial resolution and depth penetration, they only have played a minor role in mineral discoveries so far. Instead, mining and exploration companies have traditionally focused more on the use of potential field, electric and electromagnetic methods. In this context, we present a case study of an underground Vertical Seismic Profiling (VSP) experiment, which was designed to image a (semi-)massive sulfide deposit located in the Kylylahti polymetallic mine in eastern Finland. For the measurement, we used a conventional VSP with three-component geophones and a novel fiber-optic Distributed Acoustic Sensing (DAS) system. Both systems were deployed in boreholes located nearby the target sulfide deposit, and used in combination with an active seismic source that was fired from within the underground tunnels. With this setup, we successfully recorded seismic reflections from the deposit and its nearby geological contrasts. The recording systems provided data with a good signal-to-noise ratio and high spatial resolution. In addition to the measurements, we generated a realistic synthetic dataset based on a detailed geological model derived from extensive drilling data and petrophysical laboratory analysis. Specific processing and imaging of the acquired and synthetic datasets yielded high-resolution reflectivity images. Joint analysis of these images and cross-validation with lithological logging data from 135 nearby boreholes led to successful interpretation of key geological contacts including the target sulfide mineralization. In conclusion, our experiment demonstrates the value of in-mine VSP measurements for detailed resource delineation in a complex geological setting. In particular, we emphasize the potential benefit of using fiber-optic DAS systems, which provide reflection data at sufficient quality with less logistical effort and a higher acquisition rate. This amounts to a lower total acquisition cost, which makes DAS a valuable tool for future mineral exploration activities.

Reassessment of Copper Mineral Occurrence Through Electrical Tomography and Pseudo 3D Modeling in Camaquã Sedimentary Basin, Southern Brazil

The reassessment of mineral occurrences is a common and economically rational technical procedure, because it involves studies directed to targets defined in previous studies in mineral exploration. The targets definition can be based on indications of mineralization on the surface or in the contrast of measurable physical properties using geophysics and intrinsic to certain types of deposits. This paper discusses the results by the combination of the use of geophysical methods, DC resistivity and induced polarization on detailed study of a copper mineral occurrence, from the adaptation of techniques of modeling of mineral deposits in mining. The indications of mineralization in the area consist of malachite, quartz and barite in veins, recognized in volcanic tufts structurally embedded in andesites and metaconglomerates. Nine parallel lines of electrical tomography in Schlumberger arrangement were performed, which resulted in 2-D inversion models, interpolated in models of blocks, maps and pseudo 3-D isosurface models in a mineral deposits modeling program. The results allowed the recognition of areas with high chargeability (2.5 mV/V) and high resistivity (800 Ω m), relating to areas with disseminated sulphide ores and silicification, according to recognized evidence around the area distribution in regional recognition. This is where the pseudo 3-D products enabled an estimate morphology of the deposit and clearly defined targets for sampling by drilling and quantification of results. The results allow the recommendation of this procedure in mineral exploration activities, supported by the quickness and possible global reduction of project costs, with real increase in the chances of incorporation of new deposits. This Reduces the costs for research development and minimizes the environmental impacts associated with mining as well as the application of these methods for environmental diagnosis.

Iron Ore Tailing as Addition to Partial Replacement of Portland Cement

The manufacture of Portland cement used in the production of concrete emits large amounts of CO2into the atmosphere, contributing to the increase of the greenhouse effect. The environmental impact generated by the mineral exploration activity is a problem of easy verification, especially in open pit mines. The present work evaluated the possibility of using iron ore tailing as an addition to the partial replacement of the cement in mortars. The iron ore tailings were processed by drying in oven (48h at 105oC) and milling in a planetary mill (10min at 300RPM), obtaining medium grain size of 14,13 μm. For the characterization, laser granulometry, X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential thermal and thermogravimetric analysis (DTA / TGA) were performed. The sample is composed predominantly by quartz, hematite, goethite and gibbsite. After the characterization, the waste was used in the preparation of test specimens, with 10, 20 and 30% weight substitution of the cement. The composites were submitted to compression tests, with ages of 3, 7 and 28 days, using a strength rate of 0,25MPa/s. The mortars with 10, 20 and 30% of substitution presented resistance of 41.65, 36.26 and 31.64 MPa, being able to be characterized as category of Portland cement of resistance 40, 32 and 25 respectively. Considering the reduction of cement in the mortars produced, the results of compressive strength were relevant for the substitutions. The cements produced with the substitutions according to the Brazilian standards under the mechanical aspect can be classified as Portland cement.

Project Quality Management Performance: An Insight to Sustainable Development Initiatives in Oil and Gas Host Communities

A fundamental principle of project quality management is that quality is planned into project and not inspected through project. In the context of host communities in developing countries with mineral exploration activities construction projects and contracts generally is a key provider of employment in both short, medium and long term and particularly for the locals, therefore the incorporation of quality management systems in project life cycle is paramount for sustainable development. Ensuring project quality plays an important role in socio-economic development of people as it provides the most basic infrastructure that promotes economic activities. Quality management systems (QMS) has significant value relating to project quality and cost reduction and a comprehensive quality management culture can promote project success, mutual beneficial relationship and organisational sustainability. This study provides empirical findings emanating from local vendor(s) understanding, compliance and implementation of quality management systems in a multinational oil company (MNOC) community assisted projects. The study utilised SPSS version 22 for the statistical data analysis and Goodness-of-fit-test interrogated the assumption that contractors are not complying with quality management systems in project execution. The study found inter alia that 65% of the vendors are registered as closed corporation (sole proprietorship), 15% were limited liability companies, while 20% belong to other category such as subcontractors. Furthermore, 98% of the 222 respondent are yet to develop a quality manual and a conceptual nominated vendor system (NVS) project quality model was developed to improve the contract award and project management status quo, with emphasis on the need for integration of quality management systems in project life cycle for the oil and gas host communities.

Geological modeling by an indicator kriging approach applied to a limestone deposit in Indiara city - Goiás

Abstract The mineral exploration activity consists of a set of successive stages that are interdependent on each other, in which the main goal is to discover and subsequently evaluate a mineral deposit for the feasibility of its extraction. This process involves setting the shape, dimensions and grades for eventual production. Geological modeling determines the orebody's possible format in subsoil, which can be done by two approaches: vertical sections (deterministic methods) or geostatistical methods. The latter approach is currently being preferred, as it is a more accurate alternative and therefore, more reliable for establishing the physical format of orebodies, especially in instances where geologic boundaries are soft and/or with widely spaced sample information. This study uses the concept of indicator kriging (IK) to model the geologic boundaries of a limestone deposit located at Indiara city, Goias State, Brazil. In general, the results indicated a good adherence in relation to samples. However, there are reasonable differences, particularly in lithological domains with a small number of samples in relation to the total amount sampled. Therefore, the results showed that there is a need for additional sampling to better delineate the geological contacts, especially between carbonate and non-carbonate rocks. Uncertainty maps confirmed this necessity and also indicated potential sites for future sampling; information that would not be obtained by usage of deterministic methods.