Geóloga / El estudio del presente trabajo de título tiene por finalidad conocer la ocurrencia, distribución y concentraciones de tierras raras en el yacimiento El Teniente. Las tierras raras son un grupo de 17 elementos químicos: escandio, itrio y los 15 elementos del grupo de los lantánidos (lantano, cerio, praseodimio, neodimio, prometio, samario, europio, gadolinio, terbio, disprosio, holmio, erbio, tulio, iterbio y lutecio). En este trabajo se presenta el resultado para los siguientes 14 elementos: lantano, cerio, praseodimio, neodimio, samario, europio, gadolinio, terbio, disprosio, holmio, erbio, tulio, iterbio y lutecio. Para este estudio se definieron 6 unidades monolitológicas, considerando el análisis químico de 405 muestras de sondaje, siendo las siguientes: Complejo de Brechas Braden, Complejo Máfico El Teniente, Brechas de Cuarzo y Anhidrita, Pórfido Dacítico, Pórfido Diorítico y Tonalita. Las tierras raras se presentan en fosfatos, carbonatos, óxidos y silicatos. Dentro de las litologías del yacimiento las concentraciones de REE ocurren en apatito, biotita y plagioclasa a nivel traza. Las REE no presentan relación con sulfuros de cobre. Se obtuvo como resultado que las seis principales litologías presentes en el yacimiento El Teniente presentan mayores concentraciones de tierras raras livianas con respecto a las tierras raras pesadas. Las tierras raras livianas están correlacionadas entre sí, así como las tierras raras pesadas. Dentro de las tierras raras livianas las concentraciones son similares en todas las litologías, mientras que existen dos grupos dentro de las tierras raras pesadas. Se propone la presencia de dos pulsos magmáticos distintos en diferentes períodos. Las concentraciones de tierras raras dentro del yacimiento son menores que aquellas determinadas en la roca caja, la formación Farellones. Existe un empobrecimiento de las REE en los concentrados, mientras que hay un enriquecimiento de estos elementos en los relaves. El yacimiento presenta bajas concentraciones de estos elementos, con respecto a yacimientos donde se explotan las tierras raras, con un promedio inferior a la centena de ppm, por tanto, su explotación no es viable. / 02/10/2020

OBJECTIVE: To investigate the differential association of cigarette smoking with energy balance in African-American and white premenopausal women. DESIGN: Cross-sectional study of energy balance, weight, and smoking in women. SUBJECT: A total of 374 women: 191 African-American (mean age = 29.8 ± 6.5y) and 183 white women (mean age = 28.9 ± 7.1 y). MEASUREMENTS: Weight, cigarette smoking habits, resting energy expenditure, dietary intake, and physical activity. RESULTS: There were no significant differences in dietary intake by race or smoking status. The model for physical activity was significant (P = 0.0004), with body mass index (BMI) having the largest effect on activity (P<0.001). Smoking status was related to activity, with the heaviest smokers reporting more activity than nonsmokers (P= 0.008) or light smokers (P= 0.028). The model for resting energy expenditure (REE) was significant (P<0.0001), with the largest again being BMI (P<0.001). There was also an interaction between ethnicity and smoking status (P<0.0001) such that African-American nonsmokers and light smokers tended to have lower REE than several other groups, most often the African-American moderate heavy smokers. The model for BMI was significant (P<0.0001) with an interaction for ethnicity and smoking status (P = 0.0009). African-American nonsmokers and light smokers had significantly higher BMIs than most of the other groups. CONCLUSION: African-American women who were the heaviest smokers had a lower adjusted BMI than the heaviest smoking white women. This effect, at least partially, may be related to an increased REE in the African-American smoking women. While energy intake did not appear to be important in this relationship, energy expended in physical activity appeared to be increased with smoking, as was REE.

As the world moves towards more green technology and energy-resources, the need for rare earth elements (REE) has increased rapidly. A potential secondary resource for REE’s are mine tailings, and a technique to estimate the thickness of a tailing is the horizontal-to-vertical spectral ratio (HVSR) method. In this project, the depth of a mine-tailing along a profile in Blötberget was estimated using this method. The HVSR method is a non-invasive environmentally friendly seismic method which utilizes ambient noise of the Earth. The method uses seismic sensors consisting of 3 components, which measures ground motion in three directions. The acquired data was processed in the Geopsy software, where certain parameters, such as filtering and window selection, are set to make the most satisfactory results. The Geopsy software provides the user HVSRs for the selected windows. This ratio makes up a curve in the frequency domain, where a fundamental resonant frequency can be derived. The fundamental frequency is determined as the sharp, lowest-frequency peak in the data in case of a strong velocity contrast. This fundamental frequency must fulfil certain criteria to be considered reliable. When the fundamental resonant frequencies could be determined reliable, they were mathematically calculated into the thickness of the tailing by a simple mathematical formula in Excel, using the shear-wave velocity of the overlying layer and the fundamental frequency. The elevation at the location of each sensor and the thickness of the contrasting interface is used to provide a 2-D depth of the mine-tailing. This profile was compared to radiomagnetotelluric measurements. Although the measurement locations were not coinciding reasonable results were obtained.

Bergslagen är känt för sin mångfald av mineraliseringar liksom sällsynta element och mineral. Speciellt pegmatiter och vissa skarnförekomster har förhöjda koncentrationer av sällsynta jordartsmetaller (REE på engelska) och REE-förande mineral. Pegmatitprover från Flintgruvan, som ligger i norra Bergslagen (Dalarna), karakteriserades i den här studien. Proven som studerades innehöll flera REE-förande mineral; (Y,REE,U,Th)-(Nb,Ta,Ti)-oxider av AB2O6-typ, xenotim-(Y) och (Y,Yb)-förande thorit. Pegmatiten klassificerades som varandes av NYF-(Niob-Yttrium-Fluor) typ på grund av de förhöjda koncentrationerna av niob (Nb), yttrium (Y) och titan (Ti) i de undersökta faserna. Förutom yttrium så innehöll pegmatiten små koncentrationer av andra HREE (tunga sällsynta jordartsmetaller) som ytterbium (Yb) och dysprosium (Dy). (Y,REE,U,Th)-(Nb,Ta,Ti)-oxiderna innehöll även relativt höga halter av kisel (Si). På basis av de kemiska analyserna representerar dessa strakt omvandlade faser antingen aeschynit eller polykras som ursprungsmineral. Undersöknings- och analysmetoderna som användes i studien var polarisationsmikroskopi och svepelektronmikroskopi med energidispersiv spektroskopi (SEM-EDS). / Bergslagen is known for its diversity of rare elements and minerals. Especially granitic pegmatites and some uncommon types of skarn deposits have shown higher concentrations of rare earth elements (REE) and REE-bearing minerals. Samples of a granitic pegmatite from Flintgruvan, which is located in northern Bergslagen (Dalarna), were characterized in this study. The samples that were studied were found to contain several REE-rich minerals such as (Y,REE,U,Th)-(Nb,Ta,Ti) oxides of AB2O6 type, xenotime-(Y) and an Y+Yb-bearing thorite. The most abundant AB2O6 type oxides were found to represent strongly altered minerals, either belonging to the aeschynite or polycrase group. Based on mineral chemical studies, the pegmatite was classified as being of the NYF (Niobium-Yttrium-Fluorine) type due to the predominance of yttrium (Y) and niobium (Nb) as well as notable titanium (Ti) concentrations. Other than yttrium the samples contained small concentrations of other HREE (heavy rare earth elements) such as ytterbium (Yb) and dysprosium (Dy). The (Y,REE,U,Th)-(Nb,Ta,Ti) oxides also contained a relatively high content of silicon (Si). The mineralogical characterization was done by means of reflected polarized light microscopy and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS).

Metals, essential constituents of a vast number of products and industrial processes, are paradoxically confronted to a scarcity issue without precedents. Among the emerging technologies for sustainable metal recovery, bio-electrochemical systems (BES) stand at a research state with a potential application on low-content metal streams. They are based on electroactive bacteria that can exchange electrons with their environment to drive an (electro)chemical metal precipitation. The feasibility of three configurations of BES aiming to recover metals at low-energy and low-chemicals consumption was explored. A first approach inspired on metal-bacteria interactions aimed to transform gold and chromium ions into added-value products. A polarized cathode promoting the metal reduction and symbiotically producing metallic nanoparticles on bacteria was studied. A second configuration used a halophilic bioanode to recover a panel of metals including transition metals and rare earth elements from marine environments. Metals were not directly precipitated by the contact with bacteria, but via a gas-diffusion cathode coupled to the bioanode. The third configuration considered a neodymium electrochemical reduction coupled to an oxidation catalyzed by a bioanode. Here, the conventional metal-containing aqueous system was replaced by an ionic liquid, an emerging solvent suitable for REE electrodeposition. / Les métaux, composants essentiels d'un grand nombre de produits et de processus industriels, sont paradoxalement confrontés à un problème de pénurie sans précédent. Parmi les technologies émergentes pour la récupération durable des métaux, les systèmes bio-électrochimiques (BES) sont à la recherche d’une application potentielle sur des matrices aqueuses de métaux à faible teneur. Ils sont basés sur des bactéries dites électro-actives, pouvant échanger des électrons avec leur environnement afin de conduire une précipitation de (électro)chimique du métal. Le but étant d’explorer différents procédés de récupération de métaux à faible consommation d'énergie et de produits chimiques, trois configurations de BES ont été abordés. Une première approche inspirée des interactions métal-bactérie visait à transformer les ions d’or et de chrome en produits à valeur ajoutée. Une cathode polarisée favorisant la réduction des métaux et produisant de manière symbiotique des nanoparticules métalliques sur des bactéries a été étudiée. Une seconde configuration utilisait une bioanode halophile pour récupérer un panel de métaux comprenant des métaux de transition et des éléments de terres rares provenant d’environnements marins. Les métaux ne sont pas précipités directement par le contact avec les bactéries mais par une cathode à diffusion gazeuse couplée à la bioanode. La troisième configuration envisageait une réduction électrochimique au néodyme couplée à une oxydation catalysée par une bioanode. Le système aqueux contenant un métal conventionnel a été remplacé par un liquide ionique, un solvant émergent avantageux pour l'électrodéposition de terres rares.

Master of Science / Department of Geology / Matthew Totten / There are some who hold the view that liquid hydrocarbons in the upper Paleozoic formations in Kansas are being locally derived. It has been the long held belief that the liquid hydrocarbons found in Kansas have come from distant sources in Oklahoma. To shed further light on this issue about the origin of hydrocarbons in the upper Paleozoic formations in Kansas, a study was conducted to analyze the geochemical characteristics of REE in Lansing-Kansas City oils that were collected from several locations in a small area within Rooks County, Kansas. The total REE contents in these oils ranges from about 3.1 ng (or 10-12 gram) per Liter of oil to about 131 ng per Liter of oil. The pattern of relative distribution of the REEs for each oil sample has been constructed from values that were obtained by dividing the individual REE concentrations of a given oil sample by the respective concentrations of the REEs in a standard or a reference sample (such as PAAS, a representation of average argillaceous sediments in the crust that is commonly used for the analyses of a variety of crust originated sedimentary products). A standard- normalized relative distribution pattern of an oil sample can reveal an important history of chemical evolution of the oil of interest. The PAAS-normalized patterns of relative distribution of the REEs in the Lansing-Kansas City oils from Rooks County, Kansas are significantly diverse. Although nearly all oil samples investigated in this study have varied degrees of light REE-enrichment across the REE series from La to Sm, they differed in their relative Ce abundances. Some samples have positive Ce anomalies; some have negative Ce anomalies, and some others with the absence of any Ce anomaly. The oils also differed in their PAAS-normalized relative distribution of the middle rare earth elements (MREEs), ranging from Sm to Tb. All oil samples were relatively enriched in the MREEs, but with varied degrees of enrichment from a prominent one to almost a barely noticeable one. The oils differed in their relative distributions of Eu, as some were with a positive Eu anomaly, some with a negative Eu anomaly, and some with the absence of any Eu anomaly. The trends of the heavy rare earth elements (HREEs) from Tb to Lu among the oils ranged from nearly flat for the most oils to a progressive depletion across the series for few samples. Furthermore, the oils were varied in having prominently anomalous relative distributions, in some cases with a positive anomaly and in others with negative anomaly, for such elements as Tb, Ho, and Tm (MM-JS-04, MM-MC-3A, and MM-MC-01). The anomalies for Tb, Ho, Tm are reflections of enzyme activity of source material during its primary (growth) environment. The metals are known to be preferentially located at the active sites of the enzymes. The oils not only differed significantly in their REE-geochemical characteristics, they also had a wide range of K/Rb weight ratios from about 877 to about 2000. These high values are typically the ones that can be assigned to organic materials, well exceeding the range of values that are associated with common silicate minerals and rocks, having an average value of 250-350ppm. Different zones in the Lansing-Kansas City formations also show distinct REE distribution patterns. There are four broadly classified distribution patterns. MREE enrichment can be observed in samples with production from the middle Lansing-Kansas City zones (G-I). In samples with comingling Lansing-Kansas City zones, amplification of anomalies from differing source materials can be observed. The diversity in the REE distribution patterns and K/Rb ratios in oils collected from central Kansas makes a strong argument against long distance transportation from a distant source in Oklahoma

Zinkgruvan is a stratiform Zn-Pb-Ag and Cu sulphide deposit hosted by Paleoproterozoic strata in southern Bergslagen, Sweden. The deposit underwent medium-high grade regional metamorphism during the Svecokarelian orogeny, including partial melting of the host succession. Subordinate zones of semi-massive to massive magnetite and Fe-rich skarns occur in marble stratigraphically below the stratiform Zn-Pb-Ag ore but have so far not been described in detail in the scientific literature. This thesis presents results from detailed geological drill core logging, light optical microscopy (LOM) and scanning electron microscopy (SEM), which have been integrated with results from electron microprobe analysis (FE-EMPA) and whole-rock lithogeochemical analysis to provide a comprehensive description of the magnetite mineralization. Samples from the formerly mined magnetite deposits Västerby, Garpa and Åmme - distal to Zinkgruvan - have also been studied to allow for a comparison. The combined dataset has been used to 1) discuss the genesis of the magnetite mineralizations, including their relationship to base metal sulphide mineralization, and 2) evaluate potential vectors to Zn-Pb-Ag and Cu mineralization based on variations in the magnetite deposits. The semi-massive to massive magnetite, adjacent and associated Fe-rich skarn at Zinkgruvan are located in the stratigraphic upper part of the marble host. Three different varieties of magnetite mineralization can be defined: 1) semi-massive to massive magnetite mineralization in marble, 2) magnetite-bearing veins and 3) retrograde magnetite after olivine. Detailed optical microscopy has revealed a positive spatial correlation between aluminium spinel, apatite, magnetite and graphite. Semi-massive to massive magnetite mineralization at Zinkgruvan is enriched in P2O5, ΣREELa-Lu and Mn relative to a carbonate precursor. A positive correlation exists between P2O5 and ∑REELa-Lu, suggesting apatite and monazite are the primary REE-bearing minerals. The fact that the samples with highest P2O5 and ∑REELa-Lu are all Fe-rich rocks suggest the enrichment of the latter is related to the event which formed the Fe mineralization. Magnetite mineralization from the historic iron mines NW of Zinkgruvan share several key attributes with magnetite mineralization at Zinkgruvan. These include: 1) magnetite is the only iron oxide, 2) lithological and mineralogical similarities, including spatial association with marble, 3) equally high whole-rock Fe content, 4) equally high Mn (1-4 wt.% MnO), 5) equally high Eu anomalies (Eu/Eu* = 1.1- 2.8, avg. 1.75), and 6) local presence of sphalerite mineralization. Bending of the tectonic foliation from c. E-W to NW in the western part of Zinkgruvan suggest these magnetite mineralizations may be located along the same trend as those at Zinkgruvan. The normal calc-silicate mineralogy in Zinkgruvan marble (e.g. diopside, forsterite, phlogopite) can be explained by prograde regional metamorphic reactions between silicates and dolomite or calcite in impure carbonate rocks with a variable content of detrital siliciclastic and volcaniclastic material. However, the stratabound magnetite mineralization and associated Fe-rich skarns cannot be fully accounted for by this model. It is plausible that the Fe-rich skarns can be explained by similar reactions but involving more Fe-rich carbonates (ferrodolomite, ankerite, siderite). In the absence of quartz, siderite is known to thermally decompose into magnetite and graphite at temperatures above 465° C, whereby siderite-rich rocks may have been precursor to the semi-massive to massive magnetite mineralization. A recent genetic model suggests that the ore-forming fluids which formed Zinkgruvan where similar to those which formed McArthur-type SEDEX deposits. The presented results are consistent with this model, since e.g. siderite is a common alteration mineral in alteration envelopes to such deposits. Hence, magnetite mineralization, Zn-Pb-Ag and Cu-ore may all be related to the same pre-metamorphic hydrothermal system. The current genetic model places the magnetite mineralization at Zinkgruvan proximal to a fossil hydrothermal vent zone (the Burkland discontinuity). It is plausible that the magnetite mineralization mined at surface lay along the northern continuation of the Burkland discontinuity. Based on the assumption that the Burkland Cu-mineralization is most proximal and the old iron mines at Åmme are most distal along this structure, variations in whole-rock lithogeochemistry, mineral chemistry and mineralogy have been used to define nine vectors to economic Zn-Pb-Ag and Cu ore as is mined at Zinkgruvan.

The mine dumps of Kiruna-type apatite-iron oxide ore in Bergslagen, South Central Sweden, contain elevated amounts of rare earth elements (REEs). A recently started project at Uppsala University has been initiated to study these ores among others in order to document occurrences of REEs and other critical elements in the mine dumps. In this study a selection of samples from the Idkerberget deposit have been studied with respect to their geochemistry and petrography with a special focus on REE-bearing phases. In addition, their mining potential and their relationship to related ore deposits such as Blötberget, Grängesberg and Kiirunavaara have been considered. The bulk geochemistry of the ores was analyzed using ICP-ES and ICP-MS. Polished sections of the ore samples were studied using ore microscopy, SEM-EDS and WDS microprobe technique. The results indicate that the ores consist mainly of magnetite and hematite, with minor silicates, flourapatite, pyrite, chalcopyrite, monazite-(Ce), allanite-(Ce), thorium silicate, titanite and zircon. Most REEs were originally hosted in flourapatite, but metamorphic and/or hydrothermal overprinting has resulted in complex textures and neomineralisation involving exotic REE-bearing minerals such as monazite-(Ce), allanite-(Ce) and secondary flourapatite. These features have also been observed in the related ore deposits nearby. The ores are enriched in REEs by factors between 1 and 9 compared to crustal values, with LREEs being the most enriched. These enrichments are rather low compared to other REE-ores currently being mined, but the easy access to the ores could mean that mining can be profitable with the current demand of these commodities. / Varphögar av apatitjärnmalm av Kirunatyp ifrån järnmalmsbrytning i Bergslagen, Sydcentrala Sverige, innehåller förhöjda halter av sällsynta jordartsmetaller. Ett projekt vid Uppsala Universitet undersöker förekomster av sällsynta jordartsmetaller och andra kritiska element i varphögar bland annat från apatitjärnmalmer. I denna studie har prover från ett av Bergslagens apatitjärnmalmsfält, Idkerberget, undersökts geokemiskt och petrografiskt med fokus på faser som innehåller sällsynta jordartsmetaller. Deras utvinningspotential och deras relation till liknande förekomster såsom Blötberget, Grängesberg samt Kiirunavaara har också tagits i beaktning. Bulkgeokemin i proverna analyserades med ICP-EM och ICP-MS. Polerprov av malmerna undersöktes medelst optisk mikroskopi, SEM-EDS samt med WDS-mikrosondteknik. Resultaten visar att malmerna framförallt består av magnetit och hematit, med mindre mängder silikater, flourapatit, pyrit, kopparkis, monazit-(Ce), allanit-(Ce), thoriumsilikat, titanit och zirkon. Sällsynta jordartsmetaller är i huvudsak bundna i flourapatit, men metamorfa och/eller hydrotermala processer har resulterat i nybildningen av exotiska mineral såsom monazit-(Ce), allanit-(Ce), och sekundär flourapatit. Dessa egenskaper har även observerats i apatitjärnmalmer från andra platser. Proverna från Idkerberget har 1-9 gånger högre koncentration av sällsynta jordartsmetaller än jordskorpan generellt, och lätta sällsynta jordartsmetaller är de mest anrikade. Dessa halter är relativt låga jämfört med sällsynta jordartsmalmer som bryts i dagsläget, men eftersom materialet förekommer i enorma varphögar gör tillgängligheten att metallerna ändå kan utvinnas med vinst om efterfrågan på denna resurs består.

Two ombrotrophic peat bogs (NC2 and BL2) from North Stradbroke Island, Australia, were precisely dated using 210Pb and analyzed by scanning electron microscopy. Sub-samples were total digested and sequentially leached for trace and major elements concentrations using ICP-MS and ICP-OES. Total Pb concentrations in both profiles increased with the time. PAAS normalized REE patterns were characterized by relatively flat patterns, with slight enrichment in LREE, and a significant negative Eu anomaly. The temporal changes in metal concentrations, 206Pb/207Pb ratios, REEs, and ash content observed in the two profiles suggest three different periods with distinct conditions in terms of dust provenance and atmospheric pollution: (1) Pre-anthropogenic (pre-1842); (2) Early industrial (from 1840s to 1920s); (3) Industrial (post-1930s). Ombrotrophic peat bogs may be reliable archives of environmental pollution, but also shows that adjacent sites may provide contrasting evidence. Despite their close proximity, the two sites show different trends in metal deposition. Metals in NC appear to be largely bound to minerals and inorganic materials, while in BL they are mainly organic-related. Indeed the peculiar behaviour of Pb in the BL profile suggests that biological process may cause Pb isotopic fractionation. Ash contents, texture, Pb isotopic compositions, Sb/Pb values, patterns of selected trace elements (Pb, Cu, Zn, Cd, Cr, Co, Sb, Ni, Se, As, Be and Mo), and their leaching behaviours suggests that NC and BL are chemically different types of peat bogs. NC peat bog is an open sink for elements, and can be used to define regional anthropogenic impacts. In contrast, the BL site appears to be influenced by local natural and anthropogenic processes and activities, such as changes in land use. Furthermore, it demonstrated that only some of the environmental-related trace elements preserve their original depositional record. Arsenic, Be, Co, and Zn are highly mobile under weak acid conditions, and are therefore not suitable for assessing temporal trends of pollution. Cadmium, Ni, and V may also be highly mobile under certain conditions. In contrast, Pb, Cu, Cr, Mo, and Sb are not subject to vertical migration, and are useful for establishing the pollution record of ombrotrophic peat bogs.

Two ombrotrophic peat bogs (NC2 and BL2) from North Stradbroke Island, Australia, were precisely dated using 210Pb and analyzed by scanning electron microscopy. Sub-samples were total digested and sequentially leached for trace and major elements concentrations using ICP-MS and ICP-OES. Total Pb concentrations in both profiles increased with the time. PAAS normalized REE patterns were characterized by relatively flat patterns, with slight enrichment in LREE, and a significant negative Eu anomaly. The temporal changes in metal concentrations, 206Pb/207Pb ratios, REEs, and ash content observed in the two profiles suggest three different periods with distinct conditions in terms of dust provenance and atmospheric pollution: (1) Pre-anthropogenic (pre-1842); (2) Early industrial (from 1840s to 1920s); (3) Industrial (post-1930s). Ombrotrophic peat bogs may be reliable archives of environmental pollution, but also shows that adjacent sites may provide contrasting evidence. Despite their close proximity, the two sites show different trends in metal deposition. Metals in NC appear to be largely bound to minerals and inorganic materials, while in BL they are mainly organic-related. Indeed the peculiar behaviour of Pb in the BL profile suggests that biological process may cause Pb isotopic fractionation. Ash contents, texture, Pb isotopic compositions, Sb/Pb values, patterns of selected trace elements (Pb, Cu, Zn, Cd, Cr, Co, Sb, Ni, Se, As, Be and Mo), and their leaching behaviours suggests that NC and BL are chemically different types of peat bogs. NC peat bog is an open sink for elements, and can be used to define regional anthropogenic impacts. In contrast, the BL site appears to be influenced by local natural and anthropogenic processes and activities, such as changes in land use. Furthermore, it demonstrated that only some of the environmental-related trace elements preserve their original depositional record. Arsenic, Be, Co, and Zn are highly mobile under weak acid conditions, and are therefore not suitable for assessing temporal trends of pollution. Cadmium, Ni, and V may also be highly mobile under certain conditions. In contrast, Pb, Cu, Cr, Mo, and Sb are not subject to vertical migration, and are useful for establishing the pollution record of ombrotrophic peat bogs.