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  • 1.
    Bark, Glenn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kampmann, Tobias Christoph
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Life cycle assessment of European copper mining: Aims of the SUPRIM project and difficulties in dealing with geologically complex ore deposits2019In: p. 8-9Article in journal (Other academic)
  • 2.
    Bauer, Tobias
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Andersson, Joel B.H.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kampmann, Tobias Christoph
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Analysis of data from Unmanned Aerial Systems (UAS) in a Virtual Reality environment2019In: Proceedings of the Visual3D conference / [ed] Tobias C. Kampmann, 2019, p. 19-19Conference paper (Refereed)
    Abstract [en]

    The use of Unmanned Aerial Systems (UAS) is getting increasingly popular for many different types of applications. The field of geology is slowly catching up resulting in new and innovative UAS solutions for various kinds of airborne measurement techniques. These techniques comprise a wide range of geophysical and remote sensing methods used to investigate the sub-surface. At Luleå University of Technology two different types of UAS are used in combination with a Virtual Reality environment in order to analyze geological structures and related ore deposits and mineralizations. The two UAS comprise a) a custom made quadrocopter (HUGIN) with a pay load of approx. 3.5 kg and an operational time of 5 times (batteries) maximum 35 minutes depending on payload, ambient temperatures and wind speed; and b) a foldable DJI Mavic Pro with an operational time of 3 times 30 minutes. The HUGIN system can be operated with a high-resolution optical camera for photogrammetry surveys and a 3-axial fluxgate magnetometer for measuring magnetic anomalies within bedrock and ultimately delineating geological structures. The system is highly flexible and a thermal camera is currently added to the system in order detect water fluxes in relation to geological structures or exothermal mineral processes. The DJI system is equipped with an optical camera for photogrammetric surveying and is a highly valuable tool in remote areas due to its lightweight and compact construction.Data acquired from both UAS is subsequently analysed in a Virtual Reality lab utilizing a 6m wide screen with active stereo functions. Photogrammetry data is first processed using the Aigsoft software package following a Structure for Motion (SfM) workflow where dense point cloud models and subsequently meshed and textured 3D surface models are produced. These models are then converted and transferred to the GeoVisionary software package that allows visualization of models in stereo 3D view. This allows digitizing geological structures such as foliation, fractures, and faults among others in an immersive 3D environment and provides an efficient tool complimentary to traditional field mapping. In particular, this makes it possible to capture and analyse data from hardly accessible and dangerous areas such as rock faces in open pits. Another complimentary method of data analysis comprises SCAT analysis of the meshed surfaces using the MOVE software package.

  • 3.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Kumar, Rajesh
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Analysing Geospatial Techniques for Land Degradation Studies in Hindu Kush-Himalaya2019In: Environmental Change in the Himalayan Region, Springer, 2019, p. 117-136Chapter in book (Refereed)
  • 4.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Institut für Kartographie, Technische Universität Dresden.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Rock glaciers as proxies for identifying terrestrial and analogous Martian permafrost2016In: XI. International Conference On Permafrost: Book of Abstracts / [ed] Günther, F. and Morgenstern, A., Potsdam: Bibliothek Wissenschaftspark Albert Einstein , 2016, p. 535-537Conference paper (Refereed)
  • 5.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Ramírez Luque, Juan Antonio
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    UAV Imaging of a Martian Brine Analogue Environment in a Fluvio-Aeolian Setting2019In: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 11, no 18, article id 2104Article in journal (Refereed)
    Abstract [en]

    Understanding extraterrestrial environments and landforms through remote sensing and terrestrial analogy has gained momentum in recent years due to advances in remote sensing platforms, sensors, and computing efficiency. The seasonal brines of the largest salt plateau on Earth in Salar de Uyuni (Bolivian Altiplano) have been inadequately studied for their localized hydrodynamics and the regolith volume transport across the freshwater-brine mixing zones. These brines have recently been projected as a new analogue site for the proposed Martian brines, such as recurring slope lineae (RSL) and slope streaks. The Martian brines have been postulated to be the result of ongoing deliquescence-based salt-hydrology processes on contemporary Mars, similar to the studied Salar de Uyuni brines. As part of a field-site campaign during the cold and dry season in the latter half of August 2017, we deployed an unmanned aerial vehicle (UAV) at two sites of the Salar de Uyuni to perform detailed terrain mapping and geomorphometry. We generated high-resolution (2 cm/pixel) photogrammetric digital elevation models (DEMs) for observing and quantifying short-term terrain changes within the brines and their surroundings. The achieved co-registration for the temporal DEMs was considerably high, from which precise inferences regarding the terrain dynamics were derived. The observed average rate of bottom surface elevation change for brines was ~1.02 mm/day, with localized signs of erosion and deposition. Additionally, we observed short-term changes in the adjacent geomorphology and salt cracks. We conclude that the transferred regolith volume via such brines can be extremely low, well within the resolution limits of the remote sensors that are currently orbiting Mars, thereby making it difficult to resolve the topographic relief and terrain perturbations that are produced by such flows on Mars. Thus, the absence of observable erosion and deposition features within or around most of the proposed Martian RSL and slope streaks cannot be used to dismiss the possibility of fluidized flow within these features

  • 6.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martín-Torres, F. Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Revisiting enigmatic Martian slope streaks2019In: Earth Space and Science News - Editors Vox, Vol. 100Article in journal (Other academic)
  • 7.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Department of Environmental Science, Sharda University.
    Singh, Shaktiman
    Department of Environmental Science, Sharda University,.
    Sam, Lydia
    Department of Environmental Science, Sharda University,.
    Joshi, PK
    School of Environmental Sciences, Jawaharlal Nehru University, New Delhi.
    Bhardwaj, Akanksha
    Banaras Hindu University.
    Martín-Torres, Javier F.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR).
    Kumar, Rajesh
    Department of Environmental Science, Sharda University.
    A review on remotely sensed land surface temperature anomaly as an earthquake precursor2017In: International Journal of Applied Earth Observation and Geoinformation, ISSN 0303-2434, Vol. 63, p. 158-166Article in journal (Refereed)
    Abstract [en]

    The low predictability of earthquakes and the high uncertainty associated with their forecasts make earthquakes one of the worst natural calamities, capable of causing instant loss of life and property. Here, we discuss the studies reporting the observed anomalies in the satellite-derived Land Surface Temperature (LST) before an earthquake. We compile the conclusions of these studies and evaluate the use of remotely sensed LST anomalies as precursors of earthquakes. The arrival times and the amplitudes of the anomalies vary widely, thus making it difficult to consider them as universal markers to issue earthquake warnings. Based on the randomness in the observations of these precursors, we support employing a global-scale monitoring system to detect statistically robust anomalous geophysical signals prior to earthquakes before considering them as definite precursors.

  • 8.
    Brethes, Anaïs
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    An integrated study of geological, magnetic and electromagnetic data for mineral exploration in the Jameson Land Basin, central East Greenland2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Jameson Land Basin, located in central East Greenland, initiated in Devonian time with the collapse of the over-thickened Caledonian Orogen. The basin developed during different phases of rifting from the late Paleozoic to the Mesozoic and has accumulated between 16-18 km of sediments. In Paleogene time, the basin was affected by intense magmatism due to the opening of the North Atlantic Ocean c. 55 Ma ago. Due to a significant uplift in Miocene time, the sedimentary sequence is well exposed along the basin margins, revealing numerous mineral occurrences hosted within almost the entire stratigraphic succession. The major types of mineralization comprise: (1) intrusion-related Mo (± Pb, Zn, Cu, Ag) mineralization associated with Paleogene intrusive complexes; (2) stratabound and/or stratiform Cu, Pb, Zn, (Ag) within Upper Permian and Triassic clastic and marine sedimentary formations; (3) stratabound and structurally controlled Pb-Zn, Cu, Ba, (Sr) mineralization in Upper Permian carbonates; and (4) structurally-controlled Pb, Zn, Cu (±Sb, Bi, Ag, Au) vein-type mineralization within Caledonian and Paleozoic rocks.

    It is well acknowledged that structures such as faults, thrusts, detachments, shear zones and associated fracture systems play an important role as fluid conduits connecting metal sources and sites of mineral precipitation. In particular, previous studies showed that mineral occurrences within the East Greenland Caledonides are closely related to lineaments and intrusions. In this context, the Crusmid-3D project was initiated in 2014, aiming at establishing the links between the crustal structures and the mineral occurrences in the Jameson Land Basin using a combination of geological and geophysical data. The interest for mineral exploration in the area led exploration companies and institutions to carry out magnetic and electromagnetic surveys, and the data derived from these constitute the base of this study.

    This thesis provides a detailed structural interpretation of aeromagnetic data in the Jameson Land Basin where several magnetic trends associated with Tertiary dikes and sills as well as with reactivated Paleozoic and Triassic faults were delineated. These data, in combination with a literature review and compilation of the mineral occurrences in the Jameson Land Basin, allowed highlighting seven prospective areas for structurally-controlled base metal mineralization.

    New structural data from geological fieldwork, drilling results and geophysical data (magnetic, electromagnetic and seismic data) along the eastern margin of the basin allowed a new interpretation of the geometry of the Triassic rift in East Greenland, represented by NE-SW-trending basins and highs segmented by NW-SE-trending transfer zones. It can be correlated with its European conjugate margin, displaying analogies with the Triassic Froan and Helgeland Basins in the Norwegian offshore and with the Papa and West Shetlands Basins north of the Shetland Islands.

    The proposed structural model of the Triassic rift was further investigated using 3D-geologically-constrained inversion of magnetic data in order to refine the architecture of the eastern margin of the Jameson Land Basin. Modelling results confirmed the presence of a shallow westward dipping peneplained crystalline basement in the southern part of the area while the northern part is characterized by faulted blocks, which accommodated relatively thick red bed sedimentary sequences, thereby representing a good potential source of base metals.

    Furthermore, Induced Polarization (IP) effects observed in airborne time-domain electromagnetic data acquired in the eastern margin of the basin were investigated using Self-Organizing Maps (SOM). The analysis of the shape and amplitude of the transient response curves using the SOM allowed identifying four areas where the transient curve patterns exhibit strong IP effects. These are shown to be collocated with Tertiary sills and dikes, clay-altered rocks as well as with a sulfide-bearing brecciated granite and with Triassic stratigraphic horizons hosting disseminated base metal sulfides.

  • 9.
    Cockell, Charles S.
    et al.
    UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    McMahon, Sean
    UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    Lim, Darlene S.S.
    NASA Ames Research Center, Moffett Field, USA.
    Rummel, John
    SETI Institute, Friday Harbor, USA.
    Stevens, Adam
    UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    Hughes, Scott S.
    Dept. of Geosciences, Idaho State University, Pocatello, USA.
    Nawotniak, Shannon E. Kobs
    Dept. of Geosciences, Idaho State University, Pocatello, USA.
    Brady, Allyson L.
    School of Geography and Earth Sciences, McMaster University, Hamilton, Canada.
    Marteinsson, Viggo
    School of Geography and Earth Sciences, McMaster University, Hamilton, Canada.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh,Edinburgh, UK. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Harrison, Jesse
    Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland.
    Sample Collection and Return from Mars: Optimising Sample Collection Based on the Microbial Ecology of Terrestrial Volcanic Environments2019In: Space Science Reviews, ISSN 0038-6308, E-ISSN 1572-9672, Vol. 215, no 7, article id 44Article, review/survey (Refereed)
    Abstract [en]

    With no large-scale granitic continental crust, all environments on Mars are fundamentally derived from basaltic sources or, in the case of environments such as ices, evaporitic, and sedimentary deposits, influenced by the composition of the volcanic crust. Therefore, the selection of samples on Mars by robots and humans for investigating habitability or testing for the presence of life should be guided by our understanding of the microbial ecology of volcanic terrains on the Earth. In this paper, we discuss the microbial ecology of volcanic rocks and hydrothermal systems on the Earth. We draw on microbiological investigations of volcanic environments accomplished both by microbiology-focused studies and Mars analog studies such as the NASA BASALT project. A synthesis of these data emphasises a number of common patterns that include: (1) the heterogeneous distribution of biomass and diversity in all studied materials, (2) physical, chemical, and biological factors that can cause heterogeneous microbial biomass and diversity from sub-millimetre scales to kilometre scales, (3) the difficulty of a priori prediction of which organisms will colonise given materials, and (4) the potential for samples that are habitable, but contain no evidence of a biota. From these observations, we suggest an idealised strategy for sample collection. It includes: (1) collection of multiple samples in any given material type (∼9 or more samples), (2) collection of a coherent sample of sufficient size (∼10 cm3∼10 cm3) that takes into account observed heterogeneities in microbial distribution in these materials on Earth, and (3) collection of multiple sample suites in the same material across large spatial scales. We suggest that a microbial ecology-driven strategy for investigating the habitability and presence of life on Mars is likely to yield the most promising sample set of the greatest use to the largest number of astrobiologists and planetary scientists.

  • 10.
    Cárdenas, Efraín
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Particle tracking in geometallurgical testing for Leveäniemi Iron ore, Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In a particle based geometallurgical model, the behavior of the particles can be used for forecast the products and quantify the performance of the different ore types within a deposit. The particle tracking is an algorithm developed by Lamberg and Vianna 2007 whose aim is to balance the liberation data in a mineral processing circuit composed by several processing units. Currently, this tool is being developed for the HSC Chemistry software by Outotec.The objective of this study is to understand and evaluate the particle tracking algorithm in a geometallurgical test for iron ore. To achieve this objective, the liberation data is balanced in a Davis tube test circuit. A total of 13 samples from Leveäniemi iron ore were process in a Davis tube circuit.The magnetite is the main mineral in the Leveäniemi iron ore samples. Its high recovery in the Davis tube circuit along with the V, Ti and Mn suggest that these elements are present in the magnetite lattice. These penalty elements in the iron concentrates cannot be avoided at the stage of mineral concentrations.The washing effect of the Davis tubes controlled by the rotational and longitudinal agitation of the tube perturb the particles agglomeration between the pole tips of the electromagnet. A higher agitation frequency and amplitude will wash away most of the gangue minerals and also fine grained magnetite.In this work, the particle tracking is depicted and implemented in a magnetic separation circuit for high liberated material. The liberation data was balanced in a way that the particle classes can be followed through circuit and their recoveries can be calculated. Nevertheless, the algorithm requires further validation and analysis of its limitations in terms of resolution and reproducibility.

  • 11.
    Córdoba-Jabonero, Carmen
    et al.
    Instituto Nacional de Técnica Aeroespacial (INTA), Área de Investigación e Instrumentación Atmosférica, Madrid, Spain.
    Sicard, Michaël
    CommSensLab, Dept. of Signal Theory and Communications, Universitat Politècnica de Catalunya (UPC), Barcelona, Spain. Ciències i Tecnologies de l'Espai-Centre de Recerca de l'Aeronàutica i de l'Espai/Institut d'Estudis Espacials de Catalunya (CTE-CRAE/IEEC), Universitat Politècnica de Catalunya (UPC), Barcelona, Spain.
    Del Águila, Ana
    nstituto Nacional de Técnica Aeroespacial (INTA), Área de Investigación e Instrumentación Atmosférica, Madrid, Spain. emote Sensing Technology Institute, German Aerospace Centre (DLR), Oberpfaffenhofen, Germany.
    Jiménez, Marcos
    Instituto Nacional de Técnica Aeroespacial (INTA), Área de Sistemas de Teledetección, Madrid, Spain.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Performance of a dust model to predict the vertical mass concentration of an extreme Saharan dust event in the Iberian Peninsula: Comparison with continuous, elastic, polarization-sensitive lidars2019In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 214, article id 116828Article in journal (Refereed)
    Abstract [en]

    An intense dusty event unusually occurred in wintertime over the Iberian Peninsula was detected over two Spanish NASA/MPLNET sites: the temporary Torrejón Observational Tower for Environmental Monitoring (TOTEM, 40.5°N 3.5°W) and the Barcelona station (BCN, 41.4°N 2.1°E). The highest dust incidence was observed from 22 to 23 February 2017; this two-day dusty scenario is examined in order to evaluate the performance of the operational NMMB/BSC-Dust model on forecasted mass concentration profiling in comparison with polarized Micro-Pulse (P-MPL) mass estimates for dust particles. First, the optical properties of the dust (DD) were effectively separated from the non-dust (ND) component by using the combined P-MPL/POLIPHON method. Lidar-derived DD optical depths reached maximums of 1.6–1.7 (±0.1) at both stations. Typical features for dust were obtained: linear particle depolarization ratios between 0.3 and 0.4, and lidar ratios in the range of 41–70 sr and 36–66 sr, respectively, for TOTEM and BCN. Lower AERONET Ångström exponents were reported for TOTEM (0.12 ± 0.04) than at BCN (0.5 ± 0.3). HYSPLIT back-trajectory analysis showed air masses coming from the Sahara region, mostly transporting dust particles. AERONET-derived Mass Extinction Efficiencies (MEE) under dusty conditions were used for the extinction-to-mass conversion procedure as applied to the P-MPL measurements: MEE values were lower at TOTEM (0.57 ± 0.01 m2 g−1) than those found at BCN (0.87 ± 0.10 m2 g−1). Those results reveal that dust particles were predominantly larger at TOTEM than those observed at BCN, and a longer transport of dust particles from the Sahara sources to BCN could favour a higher gravitational settling of coarser particles before reaching BCN than TOTEM. A comparative analysis between profiles as obtained from the lidar DD component of the mass concentration and those forecasted by the NMMB/BSC-Dust model (25 available dusty profiles) was performed. The degree of agreement between both datasets was determined by the percentage of dusty cases satisfying selected model performance criteria (favourable cases) of two proxies: the Mean Fractional Bias, M&#x2062;F&#x2062;B" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; position: relative;">MFBM⁢F⁢B, and the correlation coefficient, C&#x2062;C" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; position: relative;">CCC⁢C. A good agreement is found (72% and 76%, respectively, of favourable cases); however, large discrepancies are found at low altitudes between the dust model and the lidar observations, mostly at early stages of the arrival of the dust intrusion. Higher model-derived centre-of-mass (CoM) heights are found in 60% of the cases (with differences < 15% w.r.t. the lidar CoM, whose values ranged between 1.8 and 2.3 km height). In addition, modelled mass loading (ML) values were generally higher than the lidar-derived ones. However, the evolution of the mass loading along the two days, 22 and 23 February, was rather similar for both the model forecasting and lidar observations at both stations. The relative ML differences (<50%) of the mass loading represented 60% of all cases. Discrepancies can be based on the uncertainties in the lidar retrievals (mainly, the use of single extinction-to-mass conversion factors). In general, a moderately good agreement is observed between the P-MPL-derived dust mass concentration profiles and the NMMB/BSC-Dust model ones at both sites; large discrepancies are found at lower altitudes, plausibly due to a lower sedimentation of dust particles coming from upper layers by gravitational settling than that introduced by the NMMB/BSC-Dust model in the simulations. The methodology described for the dust model evaluation against the continuous P-MPL observations can be easily adopted for an operational use of the NMMB/BSC-Dust model for forecasting the mass concentration profiling in frequently dust-affected regions with serious climate and environmental implications, as long as a typical MEE for dust could be accurately specified. Hence, a statistical analysis for determining AERONET-based MEE values over the Iberian Peninsula is on-going.

  • 12.
    Gunnarsson, Niklas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mineralogical speciation of sulfur in acid sulfate soils from Luleå, Sweden2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Marine sulfide – bearing sediments that oxidize when in contact with oxygen and leach outelements in high concentrations to small watercourses have been a problem for many years allover the world especially around the Bothnian Bay. The purpose of this study was to furtherinvestigate the sulfur mineralogy present in acid sulfate soils in the area of Luleå, Sweden. Asecondary aim was to see if elements leach out and accumulate in an acid sulfate soil closer tothe recipient. Samples were taken in two profiles (one oxidized and one waterlogged) fromfour sites (sites A-D) and were analyzed for whole rock geochemistry. Two sites were furtherinvestigated for mineralogy in polished samples with an optical microscope, Ramanspectroscopy and SEM-EDS. Each profile consisted of three layers: oxidation zone, transitionzone and reduced zone. The oxidation zone above the groundwater table was light grey withbrown iron hydroxide staining. Parts that lied under the water table were dark grey-black within general strong odor (“rotten eggs”) due to its sulfur content. It was usually straightforwardto distinguish and separate the layers from each other directly in the field, however in somecases pH was needed for confirmation.A general feature of investigated polished samples is the presence of abundant framboidalpyrites that are common in reduced marine sediments. The transition zone was formed in suboxicconditions and this feature is reflected by the mineralogy. Many morphologies of theframboidal pyrite were observed in this layer and signs of both dissolution and formationoccur. In the sample from site C one could observe elemental sulfur in form of large (up to 50μm) euhedral crystals. In the samples with pH<4, no sulfides occur as they have been replacedby jarosite (site B). Site C lacks these sulfur-bearing hydroxides which is thought to be due toa sulfur concentration of <0.2 %. Sulfur shows extensive leaching at most sites but at site B andD1, it accumulates in the transition zone. Elements like cobalt (Co), nickel (Ni) and zinc (Zn)are leached out or are accumulated further down in the profile. Elements that could have beentransported and have accumulated in the waterlogged profiles are Co, Ni, Zn and chromium(Cr) and in some profiles also copper (Cu) and vanadium (V).

  • 13.
    Johansson, Ellinor
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering. Luleå University of Technology.
    Biogeochemistry as an exploration tool for gold in the Brännfors area, northern Sweden2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Using plants as a sampling medium have been shown to be very successful when other exploration methods are ineffective. This is especially the case in glaciated terrains, where the overburden might be blanketing mineralised bedrock. Plants are able to take up nutrients and trace elements from the soil through different biogeochemical processes and later these concentrations can be analysed. What kind of element that is absorbed and the amount of it differ between species and even between different plant tissues. In this study, it is investigated whether biogeochemistry works as an alternative exploration method for the conditions prevailing in the Brännfors area, northern Sweden. Brännfors is an interesting area because several gold-rich boulders have been found there and an aeromagnetic survey that has been conducted in the area show positive anomalies.

    A sampling plan was designed before any sampling could take place. It was chosen to sample in profiles to delineate where the possible mineralisation is located. The sampling took place in September 2018 and was completed within two weeks. The chosen sampling medium was twigs from Scots pine (Pinus sylvestris) and they were as often as possible collected from trees of about the same age and state of health. The branches were usually cut from four metres height using a pole snipping tool. Then the twigs, with needles left on them, were cut from the branches with a hand held snipping tool. All samples were stored in paper bags, with coordinates and sample ID written on them, and was sent to ALS Scandinavia AB for analysis within a week after sampling.

    This exploration method is fast as one person can carry many samples before it gets too heavy, since one sample only weigh around 200 grams. No heavy equipment is needed either and therefore, it is possible for two persons to collect up to 30 samples/day. Moreover, the method is relatively cheap and because of the small sample size required, the method leaves a minimal impact on the environment.

    The analysed data show elevated concentrations of many elements of interest in sampled pine twigs. Especially Ag, As, Cu, Hg and Tl exhibit similar patterns in the middle of both sampling profiles, where the strongest anomalies are located along the ice movement direction from northwest. All these elements can be used as pathfinders for Au and might very well indicate a mineralisation because no previous mining activity or any other contamination risk exist in the area. Because of this, it can be said that the exploration method is working at the Brännfors area, but to a certain limit. Patterns could be clearer but there are probably several factors that influence the metal uptake of plants. Among those factors are geological and environmental issues. The possible mineralisation may for example be buried too deep below the ground surface, so that the tree roots cannot quite reach down to the bedrock.

    Several factors indicate however that the possible mineralisation is located further towards the ice movement direction instead, and that it is the ice sheet and/or the groundwater flow that have dispersed the anomalies. The gold-rich boulders found in the study area may also have been transported by the ice. The aeromagnetic anomaly can then be explained by the pyrrhotite-rich metasedimentary rock and some minor magnetite occurrences.

  • 14.
    Kampmann, Tobias Christoph
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Life cycle assessment in mining: Assembling the necessary data (SUPRIM WP3)2018Conference paper (Other academic)
  • 15.
    Kampmann, Tobias Christoph
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    MINERS – Ett nätverk för doktorander inom gruv- och prospekteringsrelaterad forskning i Sverige2019Conference paper (Other academic)
  • 16.
    Kampmann, Tobias Christoph
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Proceedings of the Visual3D conference 2019, 1–2 October 2019, Uppsala, Sweden: Visualization of 3D/4D models in geosciences, exploration and mining2019Conference proceedings (editor) (Refereed)
    Abstract [en]

    Dear colleagues,

    On behalf of the organizing committee of the Visual3D conference 2019, with the theme “Visualization of 3D/4D models in geosciences, exploration and mining”, I would like to present this proceedings document, containing all abstract contributions for which publication permission has been granted by the authors.

    EIT Raw Materials is especially acknowledged as the main sponsor of this event through the Visual3D network of infrastructure.

    We wish to thank all the contributors who through their efforts made this conference possible, and hope to see you all at a similar event in the near future.

    Yours sincerely,

    Tobias C. Kampmann, PhDConference coordinator, Visual3D conference 2019

  • 17.
    Kampmann, Tobias Christoph
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sustainability assessment: Data concerns of geoscientists2019Conference paper (Other academic)
  • 18.
    Kampmann, Tobias Christoph
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Towards better collaboration in geomodel visualization: The Visual3D network of infrastructure2018Conference paper (Other academic)
  • 19.
    Kampmann, Tobias Christoph
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Alvarenga, Rodrigo A.F.
    Ghent University, Belgium.
    Sanjuan-Delmás, David
    Ghent University, Belgium.
    Lindblom, Mats
    Boliden Mineral AB, Sweden.
    Life cycle assessment of European copper mining: A case study from Sweden2019In: Proceedings of the 15th SGA Biennial Meeting, 27-30 August 2019, Glasgow, Scotland: Life with Ore Deposits on Earth, Society for Geology Applied to Mineral Deposits , 2019, Vol. 4, p. 1577-1580Conference paper (Refereed)
    Abstract [en]

    The application of the life cycle assessment (LCA) methodology in the mining sector has the potential to evaluate the environmental sustainability of the primary production of metals. As part of a wider project on developing LCA models and methods for mining, life cycle inventory (LCI) data have been collected at two European copper-producing mine sites, Aitik (Sweden) and Cobre las Cruces (Spain). Results from Aitik, including their impact analysis, identify the use of diesel and explosives, the emission of sulfur dioxide, as well as nitrogen and other emissions in the upstream supply chain of explosives and electricity, as significant contributors to the environmental impact. These outputs have influence on the impact categories Climate Change, Photochemical Ozone Formation, Acidification, as well as Terrestrial and Marine Eutrophication. Due to the increasing incorporation of LCA into legislative demands on the mining sector, mining companies need to establish the necessary infrastructure and framework to be able to provide the required data in a fast, transparent and cost-efficient manner. For this reason, some recommendations to improve communication and data management within the companies have been established from the experience gained within this project.

  • 20.
    Kampmann, Tobias Christoph
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bauer, Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    The benefits of organized networking and matchmaking for the development of 3D/4D geomodel visualization2019In: Proceedings of the Visual3D conference 2019, 1–2 October, Uppsala, Sweden. Luleå University of Technology, 60 pages.: Visualization of 3D/4D models in geosciences, exploration and mining / [ed] Tobias C. Kampmann, Luleå, Sweden: Luleå University of Technology, 2019, p. 43-43Conference paper (Refereed)
    Abstract [en]

    While huge territory of the EU shows a very high exploration potential and many EU countries remain attractive to investors (e.g. Fraser Institute, 2015), a mere 4% of global exploration expenditure is currently invested within European countries. One tool to trigger a higher degree of investment in exploration and to secure the domestic supply of both main commodities and critical raw materials (CRM) is to enhance our three-dimensional geometric understanding of the Earth’s crust.For these reasons, EIT Raw Materials decided to fund the Visual3D network of infrastructure (NoI) for three years (2017–2019). Visual3D involves to-date 14 partner organisations from nine EU countries. The NoI aims to integrate expertise within exploration and 3D modelling from industry, academia and research institutes, with the ambition to increase the understanding of geological bodies in 3D and 4D through improved visualisation techniques. The network believes firmly that the integration of novel visualization technologies (e.g. virtual and augmented reality) into workflows of exploration, mining and geoscientific research will bring a much-needed innovation boost to the European raw materials sector and increase its competitiveness.During its first year, Visual3D has compiled the network expertise and infrastructure regarding visualization tools available at the partner facilities. An overview of this infrastructure, as well as projects conducted by network partners is available on the Visual3D homepage (www.visual3d.info). The network also managed to identify common issues in the field of geomodelling, the solutions to which may be facilitated by a pan-European network approach, such as data compatibility, communication of geomodels, as well as complexity and variety of software. Subsequent years have been dedicated to the conceptualization of possible projects in order to solve the issues name above, as well as matchmaking to find expert consortia for these projects.So far, four workshops including project partners and invited external stakeholders have been held. Networking and matchmaking during these workshops has resulted in successful project proposals in the EIT RawMaterials KAVA calls for educational (MireBooks), as well as upscaling projects (FARMIN). Both these projects are presented at the Visual3D conference 2019. Further project ideas have been discussed within Visual3D and will be developed further.The benefits of organized networking in novel research and developments fields, such as visualization of 3D/4D models for exploration and geosciences, has become apparent during the lifetime of the Visual3D network. The network partners would encourage pan-European funding institutions such as EIT RawMaterials to provide continuous funding to similar networking initiatives, especially in highly innovative and novel research fields. Well-organized communication between different stakeholders is the basis of technological innovation and has the potential to give the European raw materials sector the leading edge in this highly competitive global market.

  • 21.
    Kampmann, Tobias Christoph
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    de la Varga, Miguel
    RWTH Aachen University.
    Field augmented reality for mineral exploration and mining: An upscaling project2019In: Proceedings of the Visual3D conference 2019, 1–2 October 2019, Uppsala, Sweden: Visualization of 3D/4D models in geosciences, exploration and mining / [ed] Tobias C. Kampmann, Luleå, Sweden: Luleå University of Technology, 2019, p. 52-52Conference paper (Refereed)
    Abstract [en]

    Currently, it is still common practice in the mining industry to display three-dimensional geological, geotechnical and resource data and models as 2D projections on maps, office computers and in written reports. This introduces uncertainties and time inefficiencies regarding data acquisition, interpretation and decision-making. The need in the mining and exploration industry for an improvement of these workflows, as well as for more objective and accurate data, facilitated quality control, as well as more cost-efficient and accurate exploration targeting, has been identified within the VIisual3D network of infrastructure (www.visual3d.info). The FARMIN project aims to develop an augmented reality (AR) solution that visualizes 3D geological data and allows exploration and mining professionals to modify models in the field.We aim to close an identified development gap in the visualization of geological data: the link of gathering data in-situ, updating the models and match virtual and real coordinates while exploring in the field or working in a mine site. We will close this gap in this project, by combining developments on highly efficient 3D geomodelling with state-of-the-art augmented reality (AR) hardware and software, as well as expertise in exploration and mining. The resulting solution will be a game changer for how geologists see and collect data and update their models in the field and in the mine.Augmented reality smartglasses (e.g. Microsoft HoloLens) enable users to interact with high-definition holograms in the real world. Microsoft Hololens, for example, allows users to view, control and interact with 3D content using their hands and voice. Field-compatible augmented reality solutions, including but not limited to Microsoft HoloLens technology, coupled with interactive IoT (internet of things) networks allow not only for the manipulation of holograms in a mock-up size, but even in real scale and location. Similar technology has been successfully established in other industrial sectors such as for construction and maintenance, resulting in increased efficiency, as well as reduced operating costs and working hours.The combination of geomodelling and AR technology will be based on GemPy, an open-source library for implicit geological modelling, developed by RWTH Aachen University, and rexOS, an AR-operating system, developed by Robotic Eyes GmbH. The remaining project consortium consists of two European mining and exploration companies (Boliden Mineral, MATSA Mining), as well as a major consulting company for the mining sector (DMT), a business development company (LTU Business) and a university partner with strong expertise in exploration and ore geology research (Luleå University of Technology). The project will kick off in January 2020 and run for three years. Continuous updates on the project progress will be published via the project homepage, as well as social media channels.

  • 22.
    Kearney, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    An Investigation of the Structural Setting and Deformation of the Malmberget Iron Ore Deposits within the old Bergmästaren, Sparre and Kaptens Open Pits2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Malmberget apatite iron ore deposit is one of the most important iron producers within Europe located within an area of world-renowned mines and mining companies. It is becoming increasingly accepted that in order to increase our resources it is essential to gain a better understanding of the formation and evolution of our known mineral deposits. This thesis is part of an ongoing multi-scale 4-dimensional geological modeling project as part of a collaboration between Vinnova, LKAB, Boliden & LTU. The aim of the which is to piece together the series of geological events that are responsible for the entire Gällivare mining district as seen today. This project looks at three smaller old open pits on the outer limbs of the synform fold structure that forms the Malmberget deposit. This thesis aims to gain a better understanding of the structures that have defined this current shape, and relating them to the regional-scale structural evolution. The results show two distinct deformation events, D1and D2, with each event leaving their own signature on the region. D1 deformation resulted in the formation of high strain zones and a gneissic cleavage within the volcanic rocks. D2 deformation subsequently folded the S1 gneissic cleavage and high strain zones but without developing its own fabric.

  • 23.
    Khavari, Pourya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Characterization of Historical Tungsten Ore Tailings for Pre-selection of Feasible Reprocessing Methods Yxsjöberg, Sweden2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 24.
    Kumar, Rajesh
    et al.
    Department of Environmental Science, Sharda University, Greater Noida.
    Kumar, Ramesh
    Department of Environmental Science, Sharda University, Greater Noida.
    Singh, Shaktiman
    Department of Environmental Science, Sharda University, Greater Noida.
    Singh, Atar
    Department of Environmental Science, Sharda University, Greater Noida.
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Kumari, Anupma
    Environmental Biology Laboratory, Department of Zoology, Patna University.
    Randhawa, S.S.
    State Council for Science, Technology and Environment, Shimla.
    Saha, Ashok
    Ministry of Earth Science, New Delhi.
    Dynamics of suspended sediment load with respect to summer discharge and temperatures in Shaune Garang glacierized catchment, Western Himalaya2018In: Acta Geophysica, ISSN 1895-6572, E-ISSN 1895-7455, Vol. 66, no 5, p. 1109-1120Article in journal (Refereed)
    Abstract [en]

    The observed and predicted rise in temperature will have deleterious impact on melting of snow and ice and form of precipitation which is already evident in Indian Himalayan Region. The temperature-dependent entities like discharge and sediment load will also vary with the observed and predicted rise posing environmental, social and economic threat in the region. There is little known about sediment load transport in relation to temperature and discharge in glacierized catchments in Himalaya mainly due to the scarcity of ground-based observation. The present study is an attempt to understand the suspended sediment load and transportation in relation to variation in discharge and temperature in the Shaune Garang catchment. The result shows strong dependence of sediment concentration primarily on discharge (R2 = 0.84) and then on temperature (R2 = 0.79). The catchments with similar geological and climate setting were observed to have comparatively close weathering rate. The sediment load was found to be higher in the catchments in eastern and central part of Indian Himalayan Region in comparison with western part due to dominance of Indian Summer Monsoon leading to high discharge. The annual physical weathering rate in Shaune Garang catchment was found to be 411 t km−2 year−1 which has increased from 327 t km−2 year−1 in around three decades due to rise in temperature causing increase in discharge and proportion of debris-covered glacierized area.

  • 25.
    Rincon, Jonathan
    et al.
    University of Liege, GeMMe – Minerals Engineering and Recycling, Sart-Tilman Campus-B52, Liège, Belgium.
    Gaydardzhiev, Stoyan
    University of Liege, GeMMe – Minerals Engineering and Recycling, Sart-Tilman Campus-B52, Liège, Belgium.
    Stamenov, Lachezar
    Dundee Precious Metals Chelopech, Village of Chelopech, Bulgaria.
    Coupling comminution indices and mineralogical features as an approach to a geometallurgical characterization of a copper ore2019In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 130, p. 57-66Article in journal (Refereed)
    Abstract [en]

    A production block of the underground mine exploiting the Chelopech high sulphidation epithermal copper-gold deposit was subjected to geometallurgical modelling. This study details the procedure used based on traditional comminution and mineralogical indices. Drop weight and batch grinding tests were performed on representative samples to yield parameters related to Axb and operating work OWi indices. These were further correlated with the ore mineralogical features using principal component analysis. Modal mineralogy data processed by a set of linear equations enabled the estimation of the aforementioned indices with a deviation of ±2.4 for Axb and ±9.08 kWh/t for OWi respectively. Based on ore textural characteristics and non-sulphide gangue (NSG) minerals content, two geometallurgical domains were identified as a first approach to modelling of the studied block.

  • 26.
    Rincon, Jonathan
    et al.
    University of Liege, GeMMe – Minerals Engineering and Recycling, Sart-Tilman Campus-B52, Liège, 4000, Belgium.
    Gaydardzhiev, Stoyan
    University of Liege, GeMMe – Minerals Engineering and Recycling, Sart-Tilman Campus-B52, Liège, 4000, Belgium.
    Stamenov, Lachezar
    Dundee Precious Metals Chelopech, Village of Chelopech, 2087, Bulgaria.
    Investigation on the flotation recovery of copper sulphosalts through an integrated mineralogical approach2019In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 130, p. 36-47Article in journal (Refereed)
    Abstract [en]

    Investigation on the flotation behaviour of enargite (Cu3AsS4) and tennantite ((Cu, Fe)12As4S13) during selective copper flotation was performed using an integrated mineralogical approach. To this end, samples taken from a production block at the Chelopech mine were subjected to a laboratory scale flotation and products characterized through multi-element chemical analyses and mineral mapping using a SEM-based automated mineralogy. Chemistry, modal mineralogy, copper-sulphosalts’ liberation and associations were quantified. Principal component analysis (PCA) was employed to look for relationships between mineralogical features and flotation recovery. High variability in head copper grade was observed in the studied block, with deportment results attributing it to the varied content of enargite and tennantite. Chalcopyrite content was low in the majority of the samples. The close association and the frequently observed interlocking of pyrite and Cu-sulphosalt grains can explain pyrite (and gold) recovery during copper cleaner flotation. Linear equations based on PCA results allow the prediction of Cu-sulphosalts’ recovery with a root mean square error of ±1.32%.

  • 27.
    Singh, Kartikay
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering. EMerald Program.
    A Geometallurgical Forecast Modelfor Predicting Concentrate Quality in WLIMS Process for Leveäniemi Ore2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Previous studies have suggested that Davis tube (DT) experiment can used to study wet low intensitymagnetic separation (WLIMS) for magnetic iron ores. But DT process has never been used to mapWLIMS process, specifically in a geometallurgical framework. This thesis work is a step towardsfulfilling this gap by studying the Davis tube experiment performed on 13 different samples fromLeveäniemi iron ore deposit. The methodology adapted to map WLIMS concentrate quality includesstudy and analysis of feed, DT and WLIMS. Analyses were made using experimental data, processingdata using some analytical tools, some data-processing tools and post processing tools. For coveringthe geometallurgical aspect the analysis was done for both elements and minerals. The results fromthis study has reviled that DT can be used to predict WLIMS concentrate quality to an acceptablelevel of confidence. Furthermore, results show that a combination of DT and WLIMS informationproduce very accurate and highly reliable models for predicting and mapping WLIMS concentratequality. This work serves as the first step towards studying an unexplored field pertaining to magneticiron ore concentrate and has opened door to possible future work that could take this work a stepfurther. Supplementing this study with more data from different sample is required not only tovalidate the model but also to make it better. A better modal mineralogy of the samples is needed tounlock the full potentials of mineralogical modelling approach used in this work.

  • 28.
    Tiu, Glacialle
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering. EMerald Program.
    Classification of Drill Core Textures for Process Simulation in Geometallurgy: Aitik Mine, Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis study employs textural classification techniques applied to four different data groups: (1) visible light photography, (2) high-resolution drill core line scan imaging (3) scanning electron microscopy backscattered electron (SEM-BSE) images, and (4) 3D data from X-ray microtomography (μXCT). Eleven textural classes from Aitik ores were identified and characterized. The distinguishing characteristics of each class were determined such as modal mineralogy, sulphide occurrence and Bond work indices (BWI). The textural classes served as a basis for machine learning classification using Random Forest classifier and different feature extraction schemes. Trainable Weka Segmentation was utilized to produce mineral maps for the different image datasets. Quantified textural information for each mineral phase such as modal mineralogy, mineral association index and grain size was extracted from each mineral map. 

    Efficient line local binary patterns provide the best discriminating features for textural classification of mineral texture images in terms of classification accuracy. Gray Level Co-occurrence Matrix (GLCM) statistics from discrete approximation of Meyer wavelets decomposition with basic image statistical features[PK1]  (e.g. mean, standard deviation, entropy and histogram derived values) give the best classification result in terms of accuracy and feature extraction time. Differences in the extracted modal mineralogy were observed between the drill core photographs and SEM images which can be attributed to different sample size[PK2] . Comparison of SEM images and 2D μXCT image slice shows minimal difference giving confidence to the segmentation process. However, chalcopyrite is highly underestimated in 2D μXCT image slice, with the volume percentage amounting to only half of the calculated value for the whole 3D sample. This is accounted as stereological error.

    Textural classification and mineral map production from basic drill core photographs has a huge potential to be used as an inexpensive ore characterization tool. However, it should be noted that this technique requires experienced operators to generate an accurate training data especially for mineral identification and thus, detailed mineralogical studies beforehand is required.

  • 29.
    Tiu, Glacialle
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Extracting Mineralogical and Textural Data through Multi-scale and Multi-dimensional Imaging Techniques2018In: Microbeam Analysis in the Earth Sciences: 13th EMAS Regional Workshop, Bristol, 2018, p. 398-399Conference paper (Refereed)
1 - 29 of 29
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