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Eon : Från fotografi till sten eller konst som kunskapskällaZimmerman, Anna January 2020 (has links)
This bachelor essay describes Anna Zimmerman’s artistic process between her solo exhibition Dualities and her degree work Perfect Substance. Both works are based on an interdisciplinary balance of natural science, mysticism and poetry. Mainly these works deal with physical and existential issues so large they are almost impossible to solve. Aware of this problem Zimmerman collects existing facts and adds creative writing in an attempt to reach knowledge. Therefor, some passages in this essay can be seen as an actual sample of her artistic work since the essay-format is similar to her finished artworks. The four chapters regards, in chronological order, light, imprints and photography; poetry as a thinking method; researching; time, geology, deep time, alchemy and philosophy. These subjects are supported by subjective experiences and lectures besides works and thoughts by, most prominent, Roland Barthes, Susan Sontag, Cyprien Gaillard and Susann Kriemann.
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Factors governing marble lightness in peripheral alteration haloes around carbonate-hosted Zn-Pb-Ag-(Cu-Au) deposits, Garpenberg, SwedenEriksson, Marcus January 2020 (has links)
A Master thesis about the Garpenberg deposit located in Bergslagen, a lithotectonic domain, with a mining history that might date back as far as 350 BC. Marble- and skarn-hosted sulfide deposits are found in the area, which creates the opportunity to mine both limestone and sulfidic ore in a single mine. Garpenberg is such a location hence this thesis, which aims to quantify the factors governing spectrophotometric lightness in marble at the Dammjön ore body. The work is mainly based on five drill cores which were logged and sampled. A total of twenty-seven samples were characterized using lithogeochemical analysis and thin-section analysis. The amount of Acid Insoluble Residue (AIR), magnetic minerals and the spectrophotometric lightness were determined for the same samples. The calcite marble was divided into seven different varieties; 1) calcite marble breccia, 2) light, 3) grey, 4) green, 5) banded salmon pink, 6) ophicalcite and 7) spotted calcite marble. The dolomite marble is white to grey in color and skarn minerals are common and varies between 5-20 vol.%. Grey and light calcite marble are the varieties with the highest spectrophotometric lightness, and it could be shown that the lightness increases with a decreasing amount of titanium, aluminum and zirconium which are chemical proxies for mineralogical impurities of originally volcaniclastic origin. High-quality calcite marble is a potentially economic by-product at the Garpenberg mine, the lightest samples are nearly as light as the light standard used during analysis (92.45 out of 100%). The lightest marble is also the chemically most pure which means that the calcium oxide (CaO) and total-carbon content are high. Key geological factors detrimental to lightness and purity are the primary composition, which is determined by the admixture of volcaniclastic material in the limestone precursor. Hydrothermal alteration with the addition of silicates, sulfides and oxides forms a halo around the massive sulfide lenses. Dolomite marble, which is more proximal to ore, is richer in manganese and sulfides, and not as light as the calcite marble at Dammsjön.
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Fracture characterization in magmatic rock, a case study of the Sosa-dyke (Neuquén Basin, Argentina) / Spricknätverkskarakterisering i magmatiskt berg, en fallstudie om Sosa-intrusionen (Neuquén Basin, Argentina)Jim, Nilsson January 2020 (has links)
There are many examples worldwide were fossil magmatic intrusions influence the local water and energy supply. Due to that intrusions can act as a conductor and a reservoir, but also as a barrier for fluids and gases in the ground. The decisive feature between conductor or barrier in an intrusion is its fracture network. Hence it is of paramount importance to characterize an intrusion’s fracture network and thus its permeability. However, other than through boreholes magmatic intrusions are rather inaccessible and very little is known about their influence on aquifers and reservoir rocks in the underground. It is therefore important to increase the knowledge of magmatic intrusion by investigate the intrusions that are accessible for us at ground surface. In this study, photos from a case study about the Sosa dyke have been used to map and characterizes the fractures of the Sosa dyke, which is an accessible vertical magmatic intrusion and a part of the Chachahuén volcano complex in the southwestern parts of Argentina. The photos that were used are taken with an UAV (unmanned aerial vehicle), and to analyze the photos, map the fractures and produce the results, software as Agisoft Metashape, MOVE™ and MATLAB with the toolbox FracPaQ was used. The intrusion has two distinct fracture sets, one that is perpendicular to the intrusion margins and one that stretches parallel with the intrusion. The connectivity of the fractures is low, and since the permeability of the fractures largely depends on the connectivity, it is also low. The fracture set that is perpendicular to the intrusion margin is what’s called cooling fractures, which is created as the magma in the intrusion cools. This causes the magma to contract and break, forming fractures perpendicular to the inward migrating solidification front. The fracture set that is parallel with the intrusion is caused by minerals in the magma flow being affected by friction from the intrusion margins. This causes the minerals in the magma to elongate in the direction of flow along the sides of the dyke, creating foliation, enabling fractures to propagate along. These fracture sets are poorly connected which concludes that the mapped area of the Sosa-dyke has a low permeability. / I hela världen finns det många exempel där stelnade magmatiska intrusioner påverka ett områdes vatten och energiförsörjning, på grund av att intrusioner kan agera som ledare och reservoarer men också som barriärer för vätskor och gaser in marken. Den avgörande faktorn mellan ledare och barriärer i en intrusion är dess spricknätverk. Därför är det viktigt att kartlägga och karakterisera en intrusions spricknätverk och därmed också få en uppfattning om dess permeabilitet. Magmatiska intrusioner är förutom genom borrhål ofta svåråtkomliga, det finns därför väldigt lite information om hur de påverkar akviferer och reservoarer i marken. Det är därför viktigt att öka kunskapen om magmatiska intrusioner genom att undersöka intrusionerna som är tillgängliga vid markytan. I denna studie har bilder från en fallstudie om Sosa Intrusionen använts för att kartera och karakterisera sprickor i Sosa intrusionen. Det är en vertikal magmatisk intrusion som är synlig på markytan, och en del av Chachahuén vulkan komplexet i sydvästra Argentina. Bilderna som användes är tagna med en UAV( unmanned aerial vehicle), och för att analysera bilderna, kartera sprickorna och producera resultaten, användes programmen Agisoft Metashape, MOVE™ och MATLAB med FracPaQ verktyget. Intrusionen har två distinkta sprickgrupper, en som är vinkelrät mot intrusionens kanter och en som går parallellt med kanterna. Konnektivitet mellan sprickorna är låg och eftersom permeabiliteten påverkas av konnektiviteten är den också låg. Sprickgruppen som är vinkelrätt mot intrusionskanten är så kallade kylningssprickor och bildas nät magman i intrusionen svalnar. Det leder till att magman kontraherar och spricker, och bildar sprickor som går inåt mot stelningsgränsen och därmed vinkelrätt mot intrusionskanten. Sprickgruppen som går parallellt med intrusionen bildas av att mineral i magmaströmmen påverkas av friktion från intrusionskanterna. Det gör att mineralen lägger sig och sträcks ut i samma riktning som magmaflödet, vilket när magman stelnar bildar svaghetszoner som sprickor kan fortplanta sig i. Dessa sprickgrupper har låg konnektivitet vilket gör att slutsatsen blir att det karterade området av Sosa intrusionen har låg permeabilitet.
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Rare-Earth Elements in the Swedish Alum Shale Formation: A Study of Apatites in Fetsjön, Västerbotten / Sällsynta jordartsmetaller i Sveriges alunskiffer: en studie av apatiter i Fetsjön, VästerbottenEngström, Fredrik January 2019 (has links)
The Caledonian alum shales of Sweden host a vast number of economically interesting metals. In Fetsjön, Västerbotten, the shales contain significant amounts of rare-earth elements, vanadium, molybdenum and uranium. As metals with a multitude of high-technological applications, the former rare-earth elements (REEs) are particularly attractive in a world where the supply may be exhausted as the demand continuously increase while new deposits are not being discovered fast enough. Meanwhile, the latter uranium notably constitutes as an unwanted secondary product during the extraction of rare-earth elements. As the mineral association of the REEs in Fetsjön is unknown, the intent of this study is to analyze and thus determine their mineralogical expression. The assumed REE-bearing mineral apatite was confirmed to host the rare-earths in the Fetsjön shales after microscopy and spectrometry analyses.
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Lake Victoria - Carbon, Nitrogen, Phosphorus and Stable Isotope (δ13C) comparison between lake and catchment sedimentsBasapuram, Laxmi Gayatri Devi January 2018 (has links)
Lake Victoria situated in East Africa faces an acute problem with eutrophication. Many reasons like agricultural production, industrialization, anthropogenic processes, the introduction of species, and economic activities have caused a stress to the overall well-being of the lake. Excess carbon, nitrogen, and phosphorus drive an increase in productivity which affects eutrophication. Previous studies on sediments and nutrient concentrations in the lake have concluded that nutrient concentrations increase due to release from the catchment. This study focuses on catchment sediments collected from four different sites and compares the results with sediments from two additional sites in the lake. The sediment core from Siaya indicates the highest concentrations of TOC (180 g/kg), TN (13 g/kg) and TP (17000μg/L). It is a rural site and poor agricultural practices such as the burn and slash, use of too many fertilizers, clearance of land, atmospheric deposition and precipitation increase elemental concentrations in the sediments compared to the more urban sites. In the lake sediments, the BILL core had higher concentrations of TP (430g/kg) and TN (16 g/kg) compared to the other site (LV-95) which is located far away from the margins of the lake. This core, however, had high TOC levels (180g/kg). The increase of nutrient levels in lake sediments is thought to be due to non-point sources from the catchment. Analyses of stable carbon isotope were used to infer the different organic matter source in the sediments. Based on the range of values for δ13C vs. C/N it is inferred that aquatic algal production and C4 vascular plants are the dominant sources for the organic matter input. The chemical characterization of catchment and lake sediments provides a qualitative link to nutrient influx and eutrophication in the lake.
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Reconstruction of Holocene atmospheric mineral dust deposition from raised peat bogs in south–central SwedenSjöström, Jenny January 2018 (has links)
Atmospheric mineral dust plays a dynamic role in the climate system acting both as a forcing and a feedback mechanism. To date, the majority of paleodust studies have been conducted on marine sediments or polar ice cores, while terrestrial deposition has been less studied. As such, it is important to produce new terrestrial Holocene paleo–dust records and fill existing regional gaps. Ombrotrophic (atmospherically–fed) peat bogs can be used to reconstruct dust deposition through elemental chemistry analysis. Multi–elemental data sets are commonly used infer net dust deposition rates, source changes, grain size, and mineral composition. Mineralogical identification of dust particles is particularly important because it allows both provenance tracing and increased understanding in climate and ecosystem feedbacks. Establishing mineralogy from elemental data of mixed mineral matrixes can however be challenging. X–ray diffraction analysis (XRD) is a standard technique for mineral identification which ideally requires removal of organic matter (OM). Therefore, a test procedure was undertaken where common OM removal methods were evaluated on bulk peat samples was therefore undertaken. The results showed that combustion at 500°C was most efficient in removing OM, while leaving the majority of minerals intact, but not all. In this Licenciate thesis, early result of a paleodust study from Draftinge Mosse, southern Sweden, are also outlined. Here, the method development mentioned above was applied, enabling a combination of elemental data with mineralogy. Future work includes minor and trace element analysis by ICP–AES and ICP–MS, evaluation of the reproducibility of single core reconstructions, tests of some of the methodological assumptions used in previous paleodust studies, source tracing and paleodust reconstruction from a second site (Gällsered Mosse). / Atmosfäriskt mineraldamm, mineralpartiklar som lyfts upp i atmosfären och avsätts via eoliska processer, spelar en komplex roll i klimatsystemet då partiklarna påverkar klimatet, samtidigt som rådande klimat också påverkar partikelmängden. De flesta hittills genomförda mineraldamms- studier har utförts på marina sediment eller iskärnor trots att mineraldammspartiklar i störst utsträckning deponeras på kontinenterna. Ombrotrofa mossar (högmossar) kan användas för att rekonstruera avsättning av mineraldamm över tid genom geokemiska analyser på olika djup i torvkärnor. Den kemiska sammansättningen ger information som kan användas för att härleda variationer i partikelmängd, källområden, kornstorlek, samt mineralogisk sammansättning. Bestämning av mineralen är av särskild vikt då det möjliggör identifikation av partiklarnas källområden samt ger kunskap om partiklarnas del i klimat- och ekosystem processer. Att via geokemiska data identifiera mineral prover av blandad sammansättning är dock utmanande, särskilt då många mineral har en liknande kemisk sammansättning. Röntgen diffraktions analys (XRD) är en standardmetod inom berggrundsgeologi för att identifiera mineral, som här används på torvprover. Metoden är icke-destruktiv, men kräver att provet är relativt rent från amorfa faser, så som organiskt material. Då torv innehåller stora mängder organiskt material (>98 %), som dessutom karaktäriseras av att vara svårnedbrutet, utformades ett testprotokoll för att studera vilken metod som är bäst lämpad för att ta bort organiskt material från denna specifika jordtyp. Resultaten från genomförda tester visade att förbränning (500°C) är mest effektivt och även lämnade en majoritet av mineralen intakta, dock inte alla. I denna licenciatavhandling beskrivs även de övergripande målen med min forskning samt tidiga resultat från en mineraldammstudie från Draftinge mosse (Småland), där resultaten från metodstudien ovan applicerats och kombinerats med andra geokemiska data. Vidare arbete inom detta doktorandprojekt kommer innefatta ytterligare geokemiska analyser (spårämnesanalys med ICP-MS och ICP-AES) samt identifiering av källområden. Dessutom kommer ytterligare en mosse (Gällsered mossse) att studeras för förändringar i avsättning av mineraldamm under de senaste 7000 åren.
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Geology of Lagoa das Furnas, a crater lake on São Miguel, Azores archipelagoAndersson, Thommy January 2015 (has links)
In this thesis, the results from a geophysical mapping and coring campaign of Lagoa das Furnas are presented. Specific focus is placed on the origin of a subaqueous volcanic cone mapped in the southern part of the lake. Lagoa das Furnas is a crater lake within the Furnas volcanic centre which is located on the island of São Miguel in the Azores archipelago. The Furnas volcanic centre has a long history of earthquakes and volcanic activity. The area is relatively well-studied, except for the lake floor. Therefore, a high resolution geophysical and geological mapping survey was conducted at Lagoa das Furnas. Sidescan sonar was used to map the surface of the lake floor and single beam sonar was used to acquire sub-bottom profiles. In addition to the geophysical mapping, sediment surface sampling and core drilling were carried out followed by geochemical analyses of the retrieved material. The mapped data permitted a characterisation of the floor of Lagoa das Furnas and revealed several volcanic features including fumarole activity and a volcanic cone in the southern part of the lake. In order to unravel the origin of this cone several methods were applied, including analyses of tephra and minerals collected from the cone itself and from nearby deposits of two known eruptions Furnas I and Furnas 1630. Sedimentological, petrological, geochemical and geochronological studies of pyroclastic deposits from the cone suggest a subaqueous eruption linked to the Furnas 1630 eruption. The chemistry of glass and crystal fragments sampled from the cone suggests that it is composed of more evolved magma than that of the main Furnas 1630 implying that the lake cone is likely a product of the last eruptional phase. Historical documents reveal three lakes in Furnas valley before the 1630 eruption. Two of these lakes were lost due the eruption and the remaining lake is most likely Lagoa das Furnas and consequently did exist before the 1630 eruption.
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Constraining the Uplift History of the Al Hajar Mountains, OmanHansman, Reuben January 2016 (has links)
Mountain building is the result of large compressional forces in the Earth’s crust where two tectonic plates collide. This is why mountains only form at plate boundaries, of which the Al Hajar Mountains in Oman and the United Arab Emirates is thought to be an example of. These mountains have formed near the Arabian–Eurasian convergent plate boundary where continental collision began by 30 Ma at the earliest. However, the time at which the Al Hajar Mountains developed is less well constrained. Therefore, the timing of both the growth of the mountains, and the Arabian–Eurasian collision, needs to be understood first to be able to identify a correlation. Following this a causal link can be determined. Here we show, using apatite fission track and apatite and zircon (U-Th)/He dating, as well as stratigraphic constraints, that the Al Hajar Mountains were uplifted from 45 Ma to 15 Ma. We found that the mountains developed 33 Myr to 10 Myr earlier than the Arabian–Eurasian plate collision. Furthermore, the plate collision is ongoing, but the Al Hajar Mountains are tectonically quiescent. Our results indicate that the uplift of the Al Hajar Mountains cannot be correlated in time to the Arabian–Eurasian collision. Therefore the Al Hajar Mountains are not the result of this converging plate boundary.
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Dissolution of fluorite type surfaces as analogues of spent nuclear fuel : Production of suitable analogues and study the effect of surface orientation on dissolutionGodinho, Jose January 2011 (has links)
It is accepted worldwide that the best final solution for spent nuclear fuel is to bury it in deep geological repositories. Despite the physical and chemical barriers that are supposed to isolate the nuclear waste for at least 100.000 years, some uncertainty factors may cause underground water to get in contact with the nuclear waste. Due to radioactivity and oxidation under air, dissolution experiments using UO2 pellets are difficult and frequently lead to incoherent results. Therefore, to enable a detailed study of the influence of microstructure and surface properties on the stability of spent nuclear fuel over time, it is necessary to produce analogues that closely resemble nuclear fuel in terms of crystallography and microstructure. At the same time, in-depth understanding of dissolution phenomena is crucial to geological processes such as dissolution precipitation creep and solvent mediated phase transformations. My thesis is based in two manuscripts. Paper I reports the microstructures obtained after sintering CaF2 powders at temperatures up to 1240°C. Pellets with microstructure, density and pore structure similar to that of UO2 spent nuclear fuel pellets were obtained in the temperature range between 900°C and 1000°C. Paper II reports how differences of surface chemistry and crystal symmetry, characteristics of each surface orientation, affect the topography of CaF2 pellets described in paper I during dissolution. I propose that every orientation of the fluorite structure can be decomposed in the three reference surfaces {100}, {110} and {111}. The {111} is the most stable surface with a dissolution rate of the top surface of 1,13x10-9 mol.m-2.s-1, and {112} the less stable surface with a dissolution rate 34 times faster that {111}. Surfaces that expose both Ca and F atoms in the same plan dissolve faster, possibly because the calcium is more susceptible to be solvated. The faster dissolving surfaces are replaced by the more stable {111} and {100} surfaces which causes the development of roughness on the top surface and stabilizes the surface on high energy sites; i.e. pores or grain boundaries. The main consequences of these observations are i) the increase of the total surface area; ii) the decrease of the overall surface energy. I present a dissolution model for surfaces of crystal with different surface energies. The main conclusions are: a) dissolution rates calculated from surface area are over estimated to the real dissolution rate; b) dissolution rates are faster at the beginning of dissolution and tend to diminish with time until a minimum value is reached.
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Investigation of Thermal Maturity of Organic Matter at the Cambro Ordovician Transition in the Zagros Basin, Iran / Undersökning av termisk mognad av organiskt material vid den kambro-ordoviciska övergången i Zagrosbassängen, IranGibbons, Niall January 2021 (has links)
The thermal maturity of sediments from the upper Cambrian to lower Ordovician Mila and Ilbeyk formations in the Zagros Basin in southwestern Iran is evaluated in this thesis. A number of low-cost, fast, optical evaluation methods are utilised to assess their effectiveness for providing accurate, well constrained thermal maturity results. Palynomorph colours under transmitted light are measured using two optical evaluation methods (Palynomorph Darkness Index , PDI- Goodhue & Clayton 2010; Acritarch Alteration Index, AAI- Legall et al., 1981) to study 540 acritarchs of three acritarch morphotype-groups: acanthomorphs, Cristallinium-type and veryhachides. Correlation of the PDI and AAI results collected in this study with UV fluorescence and rock-eval pyrolysis data taken from previous studies suggests that the studied sediments are within the wet gas thermal maturity window. Furthermore, investigating the PDI results of acritarchs allowed for the identification of reworked or recycled acritarchs. Investigation of the stratigraphy of strata containing abundant reworked or recycled acritarchs allowed for the identification of a ravinement surface in a transgressive shallow water depositional environment in the studied strata.
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