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  • 1.
    Bark, Glenn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kampmann, Tobias Christoph
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Life cycle assessment of European copper mining: Aims of the SUPRIM project and difficulties in dealing with geologically complex ore deposits2019Inngår i: s. 8-9Artikkel i tidsskrift (Annet vitenskapelig)
  • 2.
    Bauer, Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andersson, Joel B.H.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kampmann, Tobias Christoph
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Analysis of data from Unmanned Aerial Systems (UAS) in a Virtual Reality environment2019Inngår i: Proceedings of the Visual3D conference / [ed] Tobias C. Kampmann, 2019, s. 19-19Konferansepaper (Fagfellevurdert)
    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 tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kumar, Rajesh
    Sam, Lydia
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Analysing Geospatial Techniques for Land Degradation Studies in Hindu Kush-Himalaya2019Inngår i: Environmental Change in the Himalayan Region, Springer Nature , 2019, s. 117-135Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Degraded land is predominantly considered as an unusable natural resource for sustaining livelihood practices such as agriculture, forestry and tourism. Land degradation poses far more grave threats in mountains where exploitable land is limited. A sustainable existence in mountainous area depends on the conservation practices adopted and a judicious utilisation of land and water resources. Due to the vastness of the Hindu Kush-Himalaya (HKH), trans-boundary issues and difficult terrain and weather conditions, geospatial techniques utilizing remote sensing and Geographical Information System (GIS) play an important role in assessing the degree of land degradation. The main focus of this chapter is on analyzing the usability and effectiveness of the geospatial approaches and methods needed to study wide-scale land degradation in the HKH mountains. This Chapter further assesses the various aspects of land degradation in mountains and highlights the markers to study land degradation. It tries to analyze the degree of anthropogenic interference on land resources in the human-dominated Himalayan region. It provides an overview of significant studies that have dealt with the assessment of land degradation in the HKH using remote sensing and GIS methodologies. The Chapter offers suggestions that future studies using geospatial techniques in resource monitoring and assessment should take heed of. Additionally, it proposes conservation and livelihood strategies for sustainable development in these high mountains.

  • 4.
    Bhardwaj, Anshuman
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Sam, Lydia
    Institut für Kartographie, Technische Universität Dresden.
    Martin-Torres, Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Rock glaciers as proxies for identifying terrestrial and analogous Martian permafrost2016Inngår i: XI. International Conference On Permafrost: Book of Abstracts / [ed] Günther, F. and Morgenstern, A., Potsdam: Bibliothek Wissenschaftspark Albert Einstein , 2016, s. 535-537Konferansepaper (Fagfellevurdert)
  • 5.
    Bhardwaj, Anshuman
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Sam, Lydia
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Martin-Torres, Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Zorzano Mier, María-Paz
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Ramírez Luque, Juan Antonio
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    UAV Imaging of a Martian Brine Analogue Environment in a Fluvio-Aeolian Setting2019Inngår i: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 11, nr 18, artikkel-id 2104Artikkel i tidsskrift (Fagfellevurdert)
    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 tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Sam, Lydia
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Martín-Torres, F. Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Zorzano, María-Paz
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Revisiting enigmatic Martian slope streaks2019Inngår i: Earth Space and Science News - Editors Vox, Vol. 100Artikkel i tidsskrift (Annet vitenskapelig)
  • 7.
    Bhardwaj, Anshuman
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. 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 tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. 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 precursor2017Inngår i: International Journal of Applied Earth Observation and Geoinformation, ISSN 0303-2434, Vol. 63, s. 158-166Artikkel i tidsskrift (Fagfellevurdert)
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    An integrated study of geological, magnetic and electromagnetic data for mineral exploration in the Jameson Land Basin, central East Greenland2018Doktoravhandling, med artikler (Annet vitenskapelig)
    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 tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. 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 tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. 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 Environments2019Inngår i: Space Science Reviews, ISSN 0038-6308, E-ISSN 1572-9672, Vol. 215, nr 7, artikkel-id 44Artikkel, forskningsoversikt (Fagfellevurdert)
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Particle tracking in geometallurgical testing for Leveäniemi Iron ore, Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    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 tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. 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 lidars2019Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 214, artikkel-id 116828Artikkel i tidsskrift (Fagfellevurdert)
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Mineralogical speciation of sulfur in acid sulfate soils from Luleå, Sweden2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser. Luleå University of Technology.
    Biogeochemistry as an exploration tool for gold in the Brännfors area, northern Sweden2019Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Life cycle assessment in mining: Assembling the necessary data (SUPRIM WP3)2018Konferansepaper (Annet vitenskapelig)
  • 15.
    Kampmann, Tobias Christoph
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    MINERS – Ett nätverk för doktorander inom gruv- och prospekteringsrelaterad forskning i Sverige2019Konferansepaper (Annet vitenskapelig)
  • 16.
    Kampmann, Tobias Christoph
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Proceedings of the Visual3D conference 2019, 1–2 October 2019, Uppsala, Sweden: Visualization of 3D/4D models in geosciences, exploration and mining2019Konferanseproceedings (Fagfellevurdert)
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sustainability assessment: Data concerns of geoscientists2019Konferansepaper (Annet vitenskapelig)
  • 18.
    Kampmann, Tobias Christoph
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Towards better collaboration in geomodel visualization: The Visual3D network of infrastructure2018Konferansepaper (Annet vitenskapelig)
  • 19.
    Kampmann, Tobias Christoph
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Upscaling mineral exploration through field augmented reality:The FARMIN project2020Konferansepaper (Annet vitenskapelig)
  • 20.
    Kampmann, Tobias Christoph
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    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 Sweden2019Inngår i: 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, s. 1577-1580Konferansepaper (Fagfellevurdert)
    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.

  • 21.
    Kampmann, Tobias Christoph
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Bauer, Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    The benefits of organized networking and matchmaking for the development of 3D/4D geomodel visualization2019Inngår i: 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, s. 43-43Konferansepaper (Fagfellevurdert)
    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.

  • 22.
    Kampmann, Tobias Christoph
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    de la Varga, Miguel
    RWTH Aachen University.
    Field augmented reality for mineral exploration and mining: An upscaling project2019Inngår i: 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, s. 52-52Konferansepaper (Fagfellevurdert)
    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.

  • 23.
    Kearney, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    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 poäng / 30 hpOppgave
    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.

  • 24.
    Khavari, Pourya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Characterization of Historical Tungsten Ore Tailings for Pre-selection of Feasible Reprocessing Methods Yxsjöberg, Sweden2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 25.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    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 Himalaya2018Inngår i: Acta Geophysica, ISSN 1895-6572, E-ISSN 1895-7455, Vol. 66, nr 5, s. 1109-1120Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 26.
    Ndebele, Mpho
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Internal geology and emplacement processes of Kimberlites, Case Study from the Tsabong Kimberlite Field, Botswana2020Independent thesis Advanced level (degree of Master (Two Years)), 80 poäng / 120 hpOppgave
    Abstract [en]

    The Crateceous (85 Ma) MK1 pipe is part of the Tsabong kimberlite cluster located approximately550km south west of Gaborone and geologically found within the Kapvaal Craton. The Tsabongkimberlite field consists of 86 known kimberlites. The MK1 pipe is the largest of this cluster at 140ha,1.7km long axis and 750m short axis and it is considered the largest diamondiferous kimberlite pipe inthe world. The kimberlite intrudes the Karoo supergroup that ranges in age from Late Carboniferousto Early Jurassic. The Karoo supergroup sequence is made of mostly glacial, siliciclastic rocks andrecently unconsolidated to semi-consolidated material. The Tsabong area consists dominantly oftillites, mudstones, siltstones, sandstones and quartzites. Only limited geological information isavailable from MK1 since the kimberlite pipe is not exposed to the surface and the exploration projectis not yet in the advanced. Because of this limited data available for understanding the morphology ofthe pipe an assumption has been made that the MK1 pipe belongs to the common type of SouthernAfrican pipes. The classical Southern African pipes consist of three pipe zones, the crater, diatreme androot zone. Furthermore, MK1 pipe displays minimal erosion and as such the current geology depictsthe results of the processes during emplacement. This study involves the investigation of the MK1emplacement process by studying its internal geology based on four boreholes by detailedsedimentological and volcanological analysis of the volcaniclastic material filling the pipe. A downholemagnetic susceptibility measurement was also conducted from the four boreholes to furtherdistinguish the internal lithofacies of the MK1 pipe. Three distinctive lithofacies have been identified,these principal lithofacies are: RVKA-resedimented volcanoclastic kimberlite A , RVKB-resedimentedvolcanoclastic kimberlite B that is divided into two sub-lithofacies RVKB C (clast supported) andRVKB m (matrix supported) and finally the PVK-pyroclastic volcaniclastic kimberlite (lower most facie).The RVKA and RVKB are formed as crater infill by re-deposition of unconsolidated pyroclastic and othersurface material. These mechanisms are normally dominated by lacustrine, fluvial and mass flows(talus and debris) processes. The post emplacement related hydrothermal alteration andmetamorphism, mainly serpentinization forming secondary magnetite is believed to have been thelargest contributor to high magnetic susceptibility readings of the MK1 facies. Contaminationprocesses such as wall rock collapse also contributed to a wide variation within the differentlithofacies. The PVK has higher average magnetic susceptibility and variation which is mostly attributedto high content of kimberlitic material and strong serpentinization of olivines resulting in high contentsof magnetite. Most of the country rock within the Tsabong area are siliciclastic sediments and occur asan important component in the RVK-resedimented volcaniclastic kimberlite resulting in generally lowmagnetic susceptibility in the RVKA and more dynamic variations within the RVKB. The emplacementof the MK1 pipe is similar to the Class 1 kimberlites. The pipe excavation is related to the initial nearsurface emplacement process characterized by violent explosive activities caused by exsolution ofjuvenile volatiles from the uprising magma. The PVK of the MK1 pipe depicts the speedy primarypyroclastic deposition processes as a result of the explosive volcanic eruptions, the PVK is dominatedby mostly pyroclastic fall material and to a lesser extent both flow and surge pyroclastic process. ThePVK is mostly medium to coarse grained, massive and homogenous unit with poorly sorted material asa result of low energy settling during eruption. The RVKB represents the pipe wall collapse duringsubsequent crater enlargement stage. This unit is made up of two sub-lithofacies with differentsedimentation processes. RVKB C is related to gravitational sidewall failure producing high energytalus mass flow deposits of poorly consolidated angular macro-clasts of mainly Permian mudstone andsiltstones of the Ecca group. The RVKB m represents debris flow dominated mass flows and ischaracterized by normal grading and lacking large country rock clasts. The RVKB m clasts are mostlysand sizes and well-rounded indicating longer transport and distal settling from the pipe wall. The RVKAconsist of tuff ring material that was subsequently filled into the remaining crater space. The RVKA 

    represents fluvial and lacustrine depositional environments, as the unit is dominated by finer grainedand bedded material of both juvenile kimberlitic material and country rock sediments. The beddedunits indicate low energy sedimentation environments as they show normal grading of clasts. Some ofthe RVKA have laminated beds that show micro faulting which may be attributed to subsidence of thevolcaniclastic infill related to gravity induced compaction of epiclastic sediments. A second eruptionmay have occurred that resulted in the displacement of the PVK unit found within the RVKA unit inborehole BH004.This also may be attributed to the characteristics of juvenile magma clasts foundwithin the volcaniclastic kimberlites that suggests an earlier crystallization and devolatisation ofprimitive kimberlite magma at depth before the vigorous fragmentation of country rock (embryonicpipe development).The MK1 also shows that there must have been a phreatomagmatic eruptioninfluence to a certain degree in the emplacement process. This is evident by the presence of somearmoured lapilli and accretionary clasts within the RVKA and RVKB facies. These phreatic explosionsmay have been during initial magma eruption or maybe synchronous with RVK resulting from nearsurface interaction of magma with groundwater which are common within the Karoo sedimentary rocks.

  • 27.
    Rentz, Ralf
    Luleå tekniska universitet, Institutionen för konst, kommunikation och lärande.
    Från insamling av data till användbar karta: Formativ undervisning för GIS-projektarbeten inom geografiundervisning på gymnasieskolan2020Independent thesis Basic level (university diploma), 5 poäng / 7,5 hpOppgave
    Abstract [sv]

    Detta utvecklingsarbete betraktar formativ undervisning för GIS-projektarbeten från insamlingav data till användbar karta inom geografiundervisning på gymnasieskolan. Studien utgår från ett sociokulturellt lärandeperspektiv där kommunikation mellan lärare och elever har en nyckelroll. Problem och frågor blir därmed utgångspunkt för lärandet och kan initiera formativ agerande av läraren. Under lektionsseriens gång har läraren försökt att hela tiden reflektera över vad den ser och vad som kan göras annorlunda i undervisningssyfte. Utifrån det har läraren bestämt sig för metoder och vägar för att sprida geografins kunskap till elever och samtidigt granska sitt agerande. En kategorisering av lärarens agerande visar att diskussioner med eleverna har en central roll inom formativ undervisning. Att diskutera med eleverna är det främsta undervisningssätt som används tillsammans med att ge instruktioner, motivera elever eller erbjuda eleverna material att arbeta vidare med. Motiv till att läraren väljer agera formativt kan uppstå i en samtalssituation med elever, i läsning av elevers skrivna material eller genom att iaktta elevernas ageranden respektive lyssnandet till deras egna diskussioner. Det visar sig att inom en lektionsserie om och med GIS ges stor möjlighet att elevers utvecklingsprocess gynnas när de gemensam utför praktiska uppgifter där de är tvungna att kommunicera och på olika sätt delar erfarenheter med varandra. Samtidigt ger det läraren chansen till att observera och reflektera med möjlighet att agera formativt. Att mäta själva effekten genom formativt agerande har förblivit svårbedömt men utifrån de gjorda erfarenheterna uppmuntras till att använda sig och pröva formativ undervisning särskilt i ramar av projektarbeten.

  • 28.
    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 ore2019Inngår i: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 130, s. 57-66Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 29.
    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 approach2019Inngår i: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 130, s. 36-47Artikkel i tidsskrift (Fagfellevurdert)
    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%.

  • 30.
    Rincon, Jonathan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Jansson, Nils
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kaiser, Christiane
    Boliden Mineral AB, Exploration department, Boliden, Sweden.
    Thomas, Helen
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Wanhainen, Christina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Persson, Mac
    Boliden Mineral AB, Exploration department, Boliden, Sweden.
    Textural and chemical characterization of sulphide minerals for improved beneficiation and exploration at the Rävliden Norra VMS deposit, Skellefte district, Sweden2020Inngår i: Abstracts and Proceedings of the Geological Society of Norway / [ed] Hans Arne Nakrem and Ann Mari Husås, Oslo: Norsk Geologisk Forening, 2020, Vol. 1, s. 179-180Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Rävliden Norra VMS deposit, represents one of the most important new discoveries in the Skellefte district (SD) in this decade. The mineralization is hosted at the transition between Skellefte group rocks (SG), dominated by coherent rhyolitic and dacitic meta-volcanic rocks, and the Vargfors group (VG), composed of metasedimentary graphitic shale interbedded with crystal-rich, monomictic to polymictic, clast-supported mass flow deposits. The ore lenses contain massive sphalerite + galena + pyrite + pyrrhotite + chalcopyrite ± Ag-Sb-Pbsulphosalts, structurally and stratigraphically above chalcopyrite + pyrrhotite stringer mineralization. The hanging wall rocks (VG) host pyrite + pyrrhotite ± arsenopyrite mineralization. Alteration in the footwall rocks, consists of sericite, chlorite, quartz, pyrite, tremolite, actinolite, carbonate and talc. The hanging wall is less altered with limited sericite or chlorite associated with minor carbonate alteration. Post ore modifications occur as, e.g. sulphides in pressure shadows, infilling of syntectonic tension gashes, “durchbewegung” texture, and sulphide-rich veins that crosscut hanging wall rocks. Significant changes in the distribution and deportment of trace and precious elements within the deposit are evident, however the implications of these on mineral processing performance and exploration vectoring has not previously been assessed in other VMS deposits in the SD. To this end, the presence of pyrite and remobilised sulphides in both hanging wall and footwall of the Rävliden Norra mineralizations, provides an opportunity to evaluate enrichment or depletion of elements hosted in the sulphide lattices or as inclusions using LA-ICP-MS. In-situ SIMS analyses in sulphide phases will allow discrimination between sedimentary and hydrothermal sulphur in the system. An investigation into the deportment of In, Ga and Ge in sphalerite and galena, will be the first assessment of these critical elements in a VMS deposit in the SD. Ultimately, integration of elemental distribution and mineral features, such as modal mineralogy, liberation degree, and grain size, with processing variables, e.g. mineral recovery, grade or flotation kinetics; will provide a better understanding of the ore performance during concentration and beneficiation.

  • 31.
    Semsari Parapari, Parisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Effects of loading mechanisms and texture on ore breakage: A multidimensional study2020Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In comminution machines, the product properties (particle size distribution, mineral liberation characteristics) and process consumables (energy for size reduction, wear) are affected by various parameters. On the one hand, understanding and optimizing these parameters can provide an energy efficient process and a specified product. On the other hand, a fundamental understanding of the breakage process can even be used for designing new or improved comminution machines.

    In this thesis, breakage fundamentals are analyzed and set against the principles of various comminution machines. The study of the breakage fundamentals is crucial for a better understanding of the effect of different comminution environments on ore types and their textures in order to achieve a desired product size and liberation. This work defines three main areas of breakage processes with breakage fundamentals, namely “loading mechanism”, “breakage mechanism” and “breakage mode”. The “loading mechanism” is defined as the physical action that is applied to a particle or several particles in order to introduce mechanical stress. The resulting pattern of the particle failure is named “breakage mechanism”. Finally, the “breakage mode” defines the particle breakage in terms of being random or non‐random. Non‐random breakage depends on the ore texture, which can be categorized as preferential breakage and phase boundary breakage.

    Promoting the breakage mode to the phase boundary breakage could help to increase the liberation degree. Various studies have assessed the effect of ore texture and operational parameters on mineral liberation. While ore texture is related to the particle inherent characteristics, operational conditions such as loading mechanism are related to the comminution environment. In all these investigations, little attempt has been made to explore the combined effects of loading mechanism and quantitative ore texture features on breakage mode and mineral liberation. In addition, a lack of fundamental understanding of the breakage process and mineral liberation can be seen.

    Accordingly, a more fundamental study of the causes behind the effects of loading mechanism and texture is required. The objective of this work is, therefore, to investigate the effects of different loading mechanisms on particle breakage and breakage mode. In order to achieve this goal, work has started with using two methods including three‐dimensional deformation and two‐dimensional crack quantification. The former method involved X‐ray computed micro‐tomography (XCT) imaging and Digital Volume Correlation (DVC) measurements while the latter was done using an image processing code in MATLAB to quantify cracks in terms of being random or preferential breakage from Scanning Electron Microscopy (SEM) images. In addition, XCT 3D imaging was used in order to track the propagated cracks in the third dimension. Moreover, phase boundary breakage was studied qualitatively based on optical microscopy images in order to identify and characterize the propagated cracks.

  • 32.
    Semsari Parapari, Parisa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Parian, Mehdi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Rosenkranz, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Characterization of ore texture crack formation and liberation by quantitative analyses of spatial deformationInngår i: Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In comminution, particle breakage starts with crack induction and propagation. The path of cracks defines the breakage mode, e.g. preferential breakage or phase boundary breakage. For investigating crack formation behavior, the description by displacement fields can be applied. The displacement fields of the mineral phases can then be used to understand breakage mode and liberation. Ore texture and operational conditions such as loading mechanisms will affect the system. One of the ore texture aspects is the ore texture heterogeneity, which is a complex quantity comprising mineral heterogeneity, geometrical heterogeneity, weak grain boundaries, and micro-cracks. This study aims at investigating the effects of ore texture and loading displacement rate on breakage mode and liberation. The approach is to describe the spatial displacement fields in different ore textures. In order to obtain these, in-situ compression loading tests with different displacement rates were conducted, followed by X-ray computed micro-tomography (XCT) and Digital Volume Correlation (DVC). In addition, the resulting cracks from ore breakage were analyzed and quantified in order to predict the breakage mode. Moreover, XCT imaging was used for tracking the propagated cracks in the third dimension. For identifying mineral phases, automated scanning electron microscopy (SEM) complemented by energy dispersive spectroscopy was applied. The outcomes showed that both ore texture and loading mechanism should be considered for describing crack formation and mineral liberation.

  • 33.
    Semsari Parapari, Parisa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Parian, Mehdi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsberg, Fredrik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Rosenkranz, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Spatial deformation of ore texture by quantitative characterization2020Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In comminution, particle breakage starts with crack initiation and propagation. For investigating crack formation behavior, the description by displacement fields can be applied. Ore texture and operational conditions such as loading mechanisms will affect the crack formation. This study aims at investigating the effects of ore texture and loading displacement rate on particle deformation. The objective is to describe the spatial displacement fields in the ore textures. In order to obtain these, in-situ compression loading with different displacement rates were conducted, followed by X-ray computed micro-tomography and Digital Volume Correlation (DVC). The outcomes showed that DVC has the potential to predict crack formation for describing mineral liberation.

  • 34.
    Semsari Parapari, Parisa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Parian, Mehdi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Rosenkranz, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Breakage process of mineral processing comminution machines – an approach to liberationInngår i: Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In comminution machines, the product properties are affected by various parameters. Optimizing these parameters can provide an energy-efficient process and a specified product. In this study, breakage fundamentals are analyzed and set against various comminution machines. The study of the breakage fundamentals is essential for a better understanding of the effect of different comminution environments on ore types in order to achieve a desired product size and liberation. While numerous investigations have been conducted to study the effect of breakage fundamentals on the comminution process, the definitions of breakage fundamentals are often used interchangeably and without caution. Thus, this review defines three main areas of breakage processes with breakage fundamental, namely “Loading mechanism”, “Breakage mechanism” and “Breakage mode”. The focus is on investigating the effects of breakage fundamentals on the comminution process and their effects on downstream processes of mineral processing plants. Despite the advances on the design of the comminution machines and relation to various ore types, still, the combined effect of breakage fundamentals, ore properties such as ore texture are not fully understood. Addressing these gaps will pave the way for choosing the proper comminution environment concerning a certain ore type.

  • 35.
    Singh, Kartikay
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi. EMerald Program.
    A Geometallurgical Forecast Modelfor Predicting Concentrate Quality in WLIMS Process for Leveäniemi Ore2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    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.

  • 36.
    Tiu, Glacialle
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi. EMerald Program.
    Classification of Drill Core Textures for Process Simulation in Geometallurgy: Aitik Mine, Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    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.

  • 37.
    Tiu, Glacialle
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Extracting Mineralogical and Textural Data through Multi-scale and Multi-dimensional Imaging Techniques2018Inngår i: Microbeam Analysis in the Earth Sciences: 13th EMAS Regional Workshop, Bristol, 2018, s. 398-399Konferansepaper (Fagfellevurdert)
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