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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Lorenz von Pansner (1777–1851): Sein Wirken als Mineraloge in Russland im Zeitraum von 1800 bis 1836, seine wissenschaftlichen Arbeiten und seine Briefkorrespondenzen

Stokratskaya, Lidia 09 May 2017 (has links) (PDF)
Im Rahmen dieser Arbeit wurden der Lebenslauf, die Reisetätigkeit, der wissenschaftliche und berufliche Werdegang Lorenz von Pansners sowie seine Bedeutung für den Aufbau der Mineralogie in Russland im 19. Jahrhundert erschlossen und analysiert. Es wurde auch seine Rolle bei der Gründung der Russischen Mineralogischen Gesellschaft analysiert. Die Grundlage dafür bildeten 57 bisher nicht bekannte Briefe von Pansner und seine wissenschaftlichen Publikationen. Verzeichnisse von in den Briefen auftretenden Personen-, Orts-, Mineral- und Gesteinsnamen sowie ein Stichwortverzeichnis sollen die Erschließung der Briefe ermöglichen, wie eine chronologisch-thematische Übersicht über den Textkorpus in Form von Konspekten und eine Liste von Kommentaren und Erläuterungen. Es wurde auch die Einordnung Pansners in die Reihe anderer multidisziplinärer Wissenschaftler des 19. Jahrhunderts sowie in die wirtschaftlichen, politischen und gesellschaftlichen Umbrüche in der Zeit zwischen den Napoleonischen Kriegen und der Deutschen Revolution unternommen.
92

Chemical and mineralogical properties of a sequence of terrace soils near Reefton, New Zealand

Campbell, Alistair Shand January 1975 (has links)
Changes brought about by chemical and physical weathering were investigated in a chronosequence of terrace soils near Reefton, New Zealand. The parent materials of the soil, which ranged in age from about 1000 to over 130,000 years were outwash gravels, sands and silts derived from granite (dominant) and indurated sandstone. Variations in pH, organic matter, particle size, cation exchange properties, total Mg, Al, Si, K, Ca, Fe and Ti, poorly-ordered and organic-complexed forms of Al and Fe, and mineralogy caused by increasing duration of weathering and by short range, short term variations in the intensity of the biotic factor were determined. It was concluded that the younger soils represented dynamic systems in which alternative weathering cycles could replace each other as the growth, death and eventual disappearance of individual red beech trees caused localised fluctuations in pH. It was further concluded that these processes would lead ultimately to the formation of gley podzols as are now found on the two oldest surfaces p and that podzolisation preceded gleying. Attempts were made to determine if minerals of the plumbogummite group were responsible for the high proportion of soil phosphate from these soils that, on fractionation, appeared in the residual P fraction. It was found that attempts to concentrate these minerals by prolonged digestion with HF resulted in their solution, and in precipitation of complex fluorides that yielded diffraction spacings that have been mistaken for minerals of the plumbogummite group.
93

Etude de Valorisation des Rejets des Usines à Zinc de Kolwezi, République Démocratique du Congo/Recovery Study of Values Metals from Kolwezi Zinc Plant Residues, Democratic Republic of Congo

NGENDA BANKA, Richard 28 April 2010 (has links)
Résumé Les rejets des Usines à Zinc de Kolwezi contiennent majoritairement du zinc sous forme réfractaire (ferrite) au traitement hydrométallurgique conventionnel. Ils contiennent d’autres métaux « lourds » qui les rendent dangereux vis-à-vis de l’environnement dans lequel ils sont actuellement entreposés. Ces métaux, dont la plupart peuvent être valorisés, font de ces rejets un véritable gisement secondaire. Il est donc impératif de mettre au point un procédé adéquat de valorisation ; d’où le thème de la présente thèse : « Etude de valorisation des rejets des Usines à Zinc de Kolwezi, RDC ». A l’aide des techniques modernes de caractérisation (physico–chimique, minéralogique et morphologique), nous sommes arrivés à cibler, à adapter et à justifier l’utilisation d’une technique de valorisation des matières minérales existantes. Les minéraux utiles contenus dans les rejets UZK ont été sulfatés par digestion et sélectivement mis en solution après un grillage. La sulfatation s’est avérée l’étape déterminante du procédé et un intérêt particulier a été focalisé sur cette étape en réalisant une étude cinétique approfondie. Les données et informations récoltées tout le long de cette recherche nous ont permis de réaliser une simulation du procédé par le logiciel ASPEN PLUS. Ce qui a permis de faire une ébauche d’un schéma de traitement industriel. Ce dernier s’est avéré souple vis-à-vis de l’utilisation d’autres matières comme les calcines des concentrés sulfurés cuivre-zinc. Residues from the Kolwezi Zinc Plant (Usines à Zinc de Kolwezi UZK) essentially contain zinc in a refractory (ferrite) form, which is difficult to recover by conventional hydrometallurgical methods. « Heavy» metals are also present that make them hazardous towards the environment in which they are currently stored. Most of these metals are valuable; thus, the UZK residues are a real secondary deposit. It is therefore imperative to develop an appropriate method of treatment, hence the theme of the present thesis: « Recovery study of values metals from Kolwezi Zinc Plant residues, DRC ». Using modern techniques of characterization (physical and chemical, mineralogical and morphological), we focused, adapted and justified the use of a technique for efficient recovery of the existing valuable minerals. The minerals contained in UZK residues have been sulphated by digestion and thereafter selectively dissolved after roasting. Sulphatation proved to be the decisive step of the process and a particular attention has been given to this step by performing a detailed kinetic study. The data and information collected throughout this research allowed a simulation of the developed method by using the « Aspen Plus » software. This allowed us to propose a draft scheme of industrial processing. The latter proved flexible towards the use of other materials such as calcines of copper-zinc sulphide concentrates.
94

Τεχνικογεωλογικές-γεωτεχνικές παράμετροι και μηχανική συμπεριφορά σκληρών εδαφών και μαλακών βράχων στο σχεδιασμό υπόγειων τεχνικών έργων / Engineering geological-geotechnical parameters and mechanical behavior of hard soils and soft rocks in the design of underground works

Κούκη, Αθανασία 23 July 2008 (has links)
Εξετάστηκαν κατ'αρχήν οι σχηματισμοί " σκληρά εδάφη-μαλακοί βράχοι" με βάση τη διεθνή και Ελληνική εμπειρία. Διερευνήθηκαν η γεωλογική σύσταση και δομή, σεισμικότητα, τεχνικογεωλογικοί χαρακτήρες και υδρογεωλογικό καθεστώς αυτών στο πλαίσιο του έργου της Ευρείας Παράκαμψης Πατρών (ΕΠΠ). Συντάχθηκε ο τεχνικογεωλογικός-γεωτεχνικός χάρτης της επριοχής έρευνας, σε κλίμακα 1:5000, αξιολογήθηκαν 170 γεωτρήσεις και διαχωρίστηκαν δύο γεωτεχνικές ενότητες των λεπτομερών αυτών ιζημάτων, Ανώτερη και Κατώτερη, οι οποίες αξιολογήθηκαν σε σχέση με τα υπόγεια τεχνικά έργα (σήραγγες). Οι ενότητες αυτές αποτυπώθηκαν σε μηκοτομές των δύο κλάδων του έργου της ΕΠΠ σε κλίμακα 1:5000/1:1000. Έγινε περαιτέρω τεκμηρίωση των ενοτήτων αυτών με βάση λεπτομερή μικροσκοπική μελέτη-ορυκτολογική ανάλυση, αξιολόγηση των εργαστηριακών και επιτόπου δοκιμών, καταγραφή παραμορφώσεων διατομής του έργου (συγκλίσεις), καθώς και ανάδρομες αναλύσεις. Η έρευνα αυτή αποτελεί χρήσιμο οδηγό διερεύνησης ανάλογων σχηματισμών για τον ασφαλή σχεδιασμό υπόγειων τεχνικών έργων. / The formations " hard soils-soft rocks" were firstly examined, based on the international and Greek territory experience. The geological composition and structure of the formations were investigated, as well as seismicity, engineering geological characteristics and hydrogeological regime of the wider area of Patras Ring Road. The engineering geological-geotechnical map of the examined area was drawn up, on a scale of 1:5000, 170 borehole logs were evaluated and two main geotechnical units in these fine sediments were distinguished, Upper and Lower, in relation to the underground works (tunnels). These Units were shown on sections along the two branches of the project, on a scale of 1:5000/1:1000. This discrimination was furthermore documented through detailed microscopic-mineralogical analysis, evaluation of the in situ and laboratory tests, as well as of the recorded deformations of the tunnels cross sections (convergenes) and finally the performance of back analysis. The investigation comprises a useful guide for the examination of such formations, concerning the safe design of underground works.
95

Minéraux argileux dans le gisement uranifère d'Imouraren (Bassin de Tim Mersoï, Niger) : implications sur la genèse du gisement et sur l'optimisation des processus de traitement du minerai / Clay minerals in uraniferous deposit of Imouraren (Tim Mersoï basin, Niger) : implications on genesis of deposit and on ore treatment process

Billon, Sophie 07 May 2014 (has links)
Les gisements uranifères nigériens sont localisés dans les formations carbonifères et jurassiques du bassin de Tim Mersoï. AREVA est actionnaire de 3 sites miniers de cette région: la SOMAÏR et la COMINAK dans le district d'Arlit, en exploitation depuis 50ans, et IMOURAREN, 80km plus au Sud, dont l'exploitation est programmée pour 2015. La minéralisation du gisement d'Imouraren est comprise dans la formation fluviatile du Tchirézrine 2 (Jurassique), formée de chenaux et de plaines d'inondation. Les faciès de remplissage de chenaux vont des grès grossiers aux grès très fins (cortège détritique : quartz et feldspaths), tandis que les faciès de débordement sont constitués d'analcimolites. La minéralogie secondaire est acquise lors de 2 évènements : 1- la diagenèse, avec formation de minéraux argileux, d'analcime, de quartz et d'albite secondaires, et 2- un épisode de circulations de fluides, qui induit une altération des minéraux détritiques et diagénétiques, la formation de nouvelles phases et le dépôt de l'uranium. Cette altération dessine une zonation minéralogique à l'échelle du gisement.L'hétérogénéité du Tchirézrine 2, tant au niveau des faciès que de la minéralogie, se perçoit lors du traitement du minerai, puisqu'il réagit différemment selon sa provenance, avec parfois des problèmes de récupération de l'U. Des essais de traitement de minerais, ont montré que analcimes et chlorites étaient les deux pénalisants, pour 3 raisons : 1- les piégeages des phases U au sein des analcimes, 2- la dissolution de ces 2 minéraux a tendance à faire sortir des conditions de solubilisation de l'U (pH et Eh) et à former de nombreux sulfates, 3- problèmes de percolation. Une méthode de détection des minerais riches en analcimes, basée sur la spectroscopie infrarouge, a été développée afin d'optimiser les mélanges de minerais et ainsi de réduire les effets néfastes des pénalisants lors du traitement. / Nigerian uraniferous deposits are located in carboniferous and jurassic formations of Tim Mersoï basin. AREVA is shareholder of 3 mine sites in this area: SOMAÏR and COMINAK, both in exploitation since 1960’s and IMOURAREN, 80km further South, whose exploitation is planned for 2015. Mineralization of Imouraren deposit is included in the fluvial formation of Tchirezrine 2 (Jurassic), composed of channels and flood plains. Facies of channel infillings range from coarse sandstones to siltstones, while overflow facies are composed of analcimolites.Secondary mineralogy was acquired during 2 stages: 1- diagenesis, with formation of clay minerals, analcime, secondary quartz and albites, and 2- stage of fluids circulations, which induced alteration of detrital and diagenetic minerals, formation of new phases and uranium deposition. A mineralogical zoning, at the scale of deposit resulted from this alteration. The heterogeneity of Tchirezrine 2, at the level of both facies and mineralogy, is also evidenced during ore treatment, as ore reacts differently depending on its source, with sometimes problems of U recovery. Ore treatment tests showed that analcimes and chlorites were both penalizing minerals, because of 1- the sequestration of U-bearing minerals into analcimes, 2- their dissolution which trends to move away from U solubilization conditions (pH and Eh) and to form numerous sulfates, and 3- problems of percolation. A detection method of analcime-rich ores, based on infrared spectroscopy, was developed in order to optimize ore blending and so to reduce negative effects during ore treatment process.
96

Evaluation of the geochemical and mineralogical transformation at an old copper mine tailings dump in Musina, Limpopo Province, South Africa

Thobakgale, Rendani 18 September 2017 (has links)
MENVSC / Department of Ecology and Resource Management / Historically, mining activities have generated vast quantities of abandoned tailings dumps in several regions of South Africa and throughout the world. The management and disposal of huge volumes of tailings dumps has constituted a major challenge to the environment. The current study aims to establish the physicochemical properties and mineralogical characterization of the old copper tailings dump in Musina, to reveal the mobility patterns and attenuation dynamics of potentially toxic or heavy metal species as a function of depth, with a view of assessing their potential environmental impact with respect to surface and ground water systems. This information is crucial in the beneficial utilization of copper tailings in the development of sustainable construction materials as part of reuse approach management system. About twelve tailings samples were collected into polyethylene plastic bags from three established tailings profiles drilled by a hand auger. The collected tailings samples were characterized using standard analytical procedures i.e., X-ray fluorescence (XRF), X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS). The transfer of potentially toxic or heavy metal species from tailings to water was evaluated using the standardized batch leaching test (EN 12457) and speciation-equilibrium calculations on the aqueous extracts performed by MINTEQA2. The leachate concentration of cations in the collected tailings samples was determined by inductively coupled mass spectrometry (ICP-MS) and the leachate concentration of anions was determined by ion chromatography (IC). A modified sequential extraction scheme was applied on the selected tailings samples of the drilled tailings profiles to further understand the mode of occurrence, the geochemical partitioning and distribution, real mobility, and environmental bioavailability of potentially toxic or heavy metal species in the tailings and tailings-soil interface. The extracted fractions or phases from sequential scheme were as follows: (F1) water-soluble fraction, (F2) exchangeable fraction, (F3) carbonate fraction, (F4) iron and manganese hydroxide associated fraction, (F5) organic matter and secondary sulphide associated fraction, (F6) primary sulphide bound fraction, and (F7) residual or silicate fraction. The results obtained from the seven steps sequential extraction scheme were validated by the determination vi of percentage recoveries from pseudo-total digestion or total metal content of the original sample. The distribution of major elements and potentially toxic or heavy metal species in different leachate fractions obtained after each step of sequential extraction of the selected tailings samples was determined by inductively coupled plasma mass spectrometry (ICP-MS). The appraised data was used to reveal the impact of atmospheric oxygen and infiltrating rain-water on the chemistry of copper tailings dump by depth profiles. Macroscopic properties revealed that the abandoned Musina copper tailings are fine to medium coarse grained, and range in color from light/dark gray at the upper or shallow depth of the tailings, to dark reddish-brown at the deeper zone where the tailings are mixed with the underlying soil or soil-interface. The drilled respective tailings profiles were uniform and slightly varied in both mineralogical and bulk chemical compositions with tailings depth. Mineralogical analysis showed the following order of mineralogical composition within the respective tailings profiles: quartz> epidote> chlorite> muscovite> calcite> hematite. Chalcopyrite was the only sulphide mineral observed by optical microscopy, although not identified or quantified by XRD and SEM-EDS analysis. The observed discrete chalcopyrite grains were attributed to the primary mined ore (i.e., chalcopyrite, chalcocite and bornite) during past copper mining activities in Musina. The tailings profiles were characterized by a medium alkaline pH (7.97-8.37) that corresponds very well with the tailings leachates or pore-water pH (8.36-8.46). This pH was constant and slightly varied with tailings depth in the respective tailings profiles. The high abundance of alumino-silicate minerals and traces of carbonates as calcite coupled with low sulphide mineral content, suggested a high neutralization capacity of the tailings which was in common agreement with an alkaline nature of the copper tailings dump. The chemical composition of major elements within the respective tailings profiles followed the order: Si>Al>Fe>Ca>Mg>K>Na, and corresponds very well with the mineralogical composition of the tailings, whereby alumino-silicates were the most abundant minerals in the tailings samples. Nevertheless, the solid-phase concentration of metals decreases with increasing tailings depth as Cu>Sr>Zr>Ni>Zn and was incongruent with the mineralogical composition within the respective tailings profiles. The main secondary minerals were calcite and hematite, and their proportion increased with increasing tailings vii depth. In addition, hematite formed coatings on the rims and corners of chlorite as observed from optical microscopy, and retained relatively high amounts of potentially toxic or heavy metals (up to 862 ppm of Cu, up to 36 ppm of Ni, and up to 25 ppm of Zn) at the upper and shallow depth of the respective tailings profiles, where bulk density was high and low porosity. Based on batch leaching tests, the amounts of potentially toxic or heavy metal species released into solution were low (0.27-0.34 μg/L Pb, 0.54-0.72 μg/L Ni, 0.88-1.80 μg/L Zn, and 20.21-47.9 μg/L Cu) and decreases with increasing tailings depth, indicating that, presently, the tailings have a minor impact on heavy metals load transported to the receiving surface and groundwater systems. The low concentration of potentially toxic or heavy metal species in solution is primarily due to their retention by secondary Fe oxide phases (i.e., hematite) and the prevailing medium alkaline pH condition of the tailings leachate or pore-water. The observations are consistent with MINTEQA2 speciation calculations, which predicted the precipitation of secondary phase cuprite (Cu2O) as the main solubility-controlling mineral phase for Cu, Zn, and Ni. Primary factors influencing aqueous chemistry at the site are neutralization and dissolution reactions as a function of pH, precipitation, and sorption into hydrous oxides (hematite and cuprite). Based on sequential extraction results, the leachable concentration of potentially toxic or heavy metal species in the water-soluble, exchangeable and carbonate fractions of the respective tailings profiles was relatively low, except for Cu and Mn. For instance, the leachable concentration of Cu and Mn reached 10.84 mg/kg and 321.7 mg/kg at the tailings-soil interface (3 m) in tailings profile C, respectively. The low concentration of potentially toxic or heavy metal species (Cr, Co, Ni, Zn, Cd, and Pb) in these fractions could be due to the low solubility of minerals bearing these trace elements caused by variations in pore-water pH in the respective tailings profiles. The high concentration of Cu and Mn in these fractions suggests their high mobility and therefore most available for uptake in the environment. Except for Cu>Mn>Cr, the contents of potentially toxic or heavy metal species in the Fe and Mn oxides and organic matter or sulphides bound fractions was low, due to the low viii quantity of these fractions in the tailings, despite their high affinity and sorption capacity for potentially toxic or heavy metal species. Likewise, the residual fraction of the respective tailings profiles contained the highest proportion of potentially toxic or heavy metal species. Although the highest potentially toxic or heavy metal species content was in fractions with limited mobility, care must be taken since any geochemical change or shift in the tailings pH or acidic conditions may cause them to be displaced to more mobile fractions, thereby increasing their mobility and environmental bioavailability. Therefore, physicochemical properties of the tailings including pH and mineralogical composition of the tailings samples were the main substrate controlling the geochemical partitioning and distribution, potential mobility, and environmental bioavailability of potentially toxic or heavy metal species by tailings depth. The knowledge of mobility and eco-toxicological significance of tailings is needed when considering tailings dump disposal or reuse in the environment. The addition of copper tailings at 3 and 28 days successfully improved the compressive strength of cement mortar mixtures incorporating tailings at C5 (5%) and C10 (10%) respectively, although with small margin relative to the control mixture (C0). The maximum strength was 31.15 Mpa attained after 28 curing days, and slightly varied when compared with other compressive strength on copper blended cement mortars mixtures in other countries, used for the development of sustainable construction materials. The chemical composition, physical properties and improved compressive strength on cement mortars mixtures incorporating copper tailings, implies that copper tailings are suitable for the development of sustainable construction materials, thereby ensuring job creation, availability of land for development usage, and the reduction of environmental pollution induced by the abandoned copper tailings dumps.
97

Lorenz von Pansner (1777–1851): Sein Wirken als Mineraloge in Russland im Zeitraum von 1800 bis 1836, seine wissenschaftlichen Arbeiten und seine Briefkorrespondenzen

Stokratskaya, Lidia 29 November 2016 (has links)
Im Rahmen dieser Arbeit wurden der Lebenslauf, die Reisetätigkeit, der wissenschaftliche und berufliche Werdegang Lorenz von Pansners sowie seine Bedeutung für den Aufbau der Mineralogie in Russland im 19. Jahrhundert erschlossen und analysiert. Es wurde auch seine Rolle bei der Gründung der Russischen Mineralogischen Gesellschaft analysiert. Die Grundlage dafür bildeten 57 bisher nicht bekannte Briefe von Pansner und seine wissenschaftlichen Publikationen. Verzeichnisse von in den Briefen auftretenden Personen-, Orts-, Mineral- und Gesteinsnamen sowie ein Stichwortverzeichnis sollen die Erschließung der Briefe ermöglichen, wie eine chronologisch-thematische Übersicht über den Textkorpus in Form von Konspekten und eine Liste von Kommentaren und Erläuterungen. Es wurde auch die Einordnung Pansners in die Reihe anderer multidisziplinärer Wissenschaftler des 19. Jahrhunderts sowie in die wirtschaftlichen, politischen und gesellschaftlichen Umbrüche in der Zeit zwischen den Napoleonischen Kriegen und der Deutschen Revolution unternommen.
98

Studium chování vybraných hornin při působení vysokých teplot / Study of the behavior of selected rocks at high temperatures

Holanec, Aleš January 2022 (has links)
The diploma thesis deals with the observation and diagnostics of transformations that take place in stone slabs of different mineralogical composition during heating to high temperatures. The theoretical part of the thesis deals with a summary of available information about selected types of rocks. Furthermore, it presents findings from the experimental thermal loading of a granite sample. The principles and instruments of laboratory experimental methods that are used to judge the resistance of rocks are described in detail. In the experimental part, the testing methodology is proposed, the procedure of production of rock test specimens is described and the way in which the thermal loading of stone slabs took place is explained. The results of the experiments are shown in the tables and graphs. A comparison of individual tests and properties of selected samples and evaluation of the obtained results is performed.
99

Geological characterization of rock samples by LIBS and ME-XRT analytical techniques

Elvis Nkioh, Nsioh January 2022 (has links)
One of the major challenges in earth sciences and mineral exploration has been to determine with high accuracy and at a fast rate the elemental composition as well as the general chemistry of a rock sample. Many analytical techniques e.g., scanning electron microscopy (SEM) have been employed in the past with a certain degree of success, but their analyses usually require a lengthy sample preparation and time-consuming measurements which produce results at a much slower rate than techniques whichrequire less or do not require any sample preparation at all. SEM images the surface of a sample by scanning it with a high-energy beam of electrons in a raster scan pattern, where the primary electron beam produced under very low air pressure vacuum scans across the sample by striking it, and a variation of signals produce an image of the surface, or its elemental composition together with energy dispersive X-rays. Alternatively, laser induced breakdown spectrometry (LIBS) and multi energy X-ray transmission (ME-XRT) are non-contact measurement scanning techniques, capable of producing faster results than SEM-EDS which makes them suitable for real time measurements and analyses as they do not slow down the pace of a project being carried out. LIBS is a spectroscopic technique used to characterize and detect materials where a highly energetic laser pulse is focused onto the surfaces of solids, liquids or gases resulting in atomic and molecular species to emit light at specific wavelengths which is collected with a spectrometer and analysed using a computer. Comparably, ME-XRT is a sensor-based sorting technique involving the planar projection of X-ray attenuation of a particle stream, distributed on a fast conveyor belt, where they are scanned and evaluated while passing and an image is recorded by a line scan detector.      Eleven rock samples were analysed in this study. They include four rock type samples: granite, basalt, sandstone, and gneiss, all obtained from Luleå University of Technology (LTU) sample storage and seven ore type samples which include a porphyry Cu sulphide ore, a porphyry Cu oxide ore, a porphyry Cu-Au-Ag ore, an apatite iron ore (AIO), an iron-oxide copper gold ore (IOCG), an orogenic gold ore and a volcanogenic massive sulphide ore (VMS).       The SEM results give a semi-quantitative elemental composition of the rocks, which may be usedto discriminate mineralisation. Energy dispersive X-ray spectroscopy (EDS) maps may be used to identifygeological features and secondary electron (SE) images may be used to understand the topography of the rock samples. The SEM has a low penetration depth rate but produces moderate to high accuracy resultsdepending on the settings and calibrations. It requires a lengthy sample preparation, and its analytical time is often too long for routine industrial application. LIBS results also provide rock elemental compositions similar to the SEM, which may be quantitative if the same spectrometer is used for all elements and calibrated against a standard. It also produces element maps similar to the SEM-EDS maps. LIBS analyses yield high accuracy results but at a low penetration depth. There are no standard calibrations for the LIBS measurements, which limits quantification. LIBS measurements do not require any form of sample preparation. ME-XRT analyses result in rock chemical data portraying a light material fraction (aluminium-like) and a heavy material fraction (iron-like) which may be used to distinguish different rock samples based on the closeness of their effective atomic number Zeff to that of aluminium and iron respectively. It’s analysis also produces low-resolution images of the analysed rock samples. The image resolution is too low to allow interpretation of the data in the context of the structures and textures in the rock samples. It has a higher penetration depth than LIBS and SEM-EDS producing more volumetric data but with a lower accuracy in terms of the amount of information obtained. Only two elements are used for ME-XRT calibration measurements, if many elements of varying atomic numbers could be used, it would have the ability to provide a more reliable data. Samples must have a maximum and minimum thickness; thus, sample preparation is required to regulate the rock thickness.      SEM and LIBS provide element compositions of minerals and element distribution maps required by geologist in their daily activities during exploration and mining. This information can be considered the most useful obtained from all three techniques. However, LIBS analyses are faster, and its maps are of higher quality even at the same resolution as the SEM-EDS. This makes the LIBS preferable for real time measurements and analyses. Geological activities like drill core logging, mine mapping and sampling for grade control all require fast results for project continuity and LIBS is suitable for this purpose as it can keep up with the pace of these activities. SEM analytical technique provides semi-quantitative data which is more accurate than the LIBS data and thus, preferable for usage in research institutions and universities.ME-XRT can reveal information on the internal structures or different rock sample compositions. This makes it a suitable technique in distinguishing ore from waste material especially in iron ore mining and processing where the iron needs to be separated from the siliceous waste and sorting is also required prior to beneficiation to avoid equipment destruction by abrasive quartz. LIBS and ME-XRT analytical techniques complement each other in terms of analytical capabilities as LIBS has a low penetration depthrate but high accuracy results while the ME-XRT has a high penetration depth rate but low accuracy results. They are both fast scanning techniques that can be used for real time measurements and analyses and if their analytical prowess can be improved, the combination of these two fast analytical techniques may enable us to obtain high quality data and may as well be what is needed by geologists in the future.

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