The Understen-Märket trench is located in the Southern Quark and is the only deep-water connection between the Baltic Propper and the Gulf of Bothnia. Bathymetric mapping reveals a number of eroded channels and drift deposits exists on the seafloor, indicating that the area is heavily affected by current activity. Bottom current behavior in the area is not thoroughly understood, but generally in the BalticBasin, there is southward flowing fresh surface waters compensated by denser northward-flowing more saline bottom waters. The dominant direction of flow for bottom waters in the Southern Quark is northward. Northward speeds often exceed the threshold required to erode fine material on the seafloor. Using geophysical data and marine sediment cores, this study shows that current eroded channels and drift deposits in the Understen-Märket trench were initially formed in the late Holocene between 3 – 4kyr BP, during the transition from the Littorina to the Post Littorina stages of the Baltic Sea. Application of the sortable silt (SS) proxy for current sorting show three distinct regimes that closely match the assigned lithologic units (LU) based on core descriptions. Downcore grain size analysis of three marine sediment cores reveals a gradual boundary to sandy sediments that caps two of the cores recovered from an eroded channel. The third core was recovered from the drift deposit which mostly consists of silt. The progressive coarsening suggests that the current activity has increased during the late Holocene. A simplified model is presented that shows how moderate (20-50 m) shallowing of the sill, which has occurred in response to isostatic rebound between 8 and 4 kyr BP, could have generated the higher current speeds seen today. However, this should be explored using more advanced paleo-circulation models.

Tiñuformationen i Oaxaca, Mexiko är den enda fossilförande enheten från undre paleozoikum mellan den Laurentiska plattformen i nordvästra Mexiko och de Gondwanska lagerföljderna i Sydamerika. Det har nyligen visats att Tiñusektionen är en koncentrerad passiv kantlagerföljd med Gondwanakaraktär. Formationen delas upp i två delar; Yudachica från översta kambrium, som vilar okonformt på mellanproterozoisk grund, och Río Salinas från undre ordovicium (tremadoc). Formationen har tidigare studerats med avseende på dess avsättningsmiljöer och det fossila innehållet av trilobiter och konodonter vilka båda ger utmärkt biostratigrafisk kontroll över formationen. Ungefär 1000 exemplar av Linguliforma brachiopoder från tolv kalkstenslager från Tiñuformationen har studerats. Detaljerade undersökningar om taxonomi och stratigrafisk distribution av taxa har utförts. Faunan omfattar nio acrotretida taxa och en ny siphonotretid art och ett fåtal lingulida fragment. De acrotretida och det siphonotretida taxa har beskrivits grundligt och klassificerats till släkte. / The Tiñu Formation of Oaxaca State (Mexico) is the only fossiliferous lower Palaeozoic unit between the Laurentian platform in northwest Mexico and the Gondwanan successions in Andean South America. It has recently been shown that the Tiñu section is a condensed passive margin succession with Gondwanan character. The formation is divided into two members, namely, the uppermost Cambrian Yudachica Member, which rests nonconformably on a middle Proterozoic basement, and the Lower Ordovician (Tremadoc) Río Salinas Member. The formation has been studied with respect to its depositional environments and its fossil content of trilobites and conodonts, both providing excellent biostratigraphical control for the formation. About 1000 specimens of Linguliform brachiopods of twelve limestone horizons of the Tiñu Formation have been studied. Detailed investigations on taxonomy and stratigraphic distribution of the taxa have been made. The fauna comprises nine acrotretid taxa, a new siphonotretid species and a few linguloid fragments. The acrotretid and siphonotretid taxa have been thoroughly describes and classified to genus.

Water ingress into rock tunnels is a problematic phenomenon – especially in urban areas – as a lowered groundwater table may cause harmful settlements. Furthermore, too much ingress can be an incentive for the environmental court to halt the tunnel process, in order to protect the nature as part of a national interest.Water ingress is normally lowered by injecting a water and cement mixture into boreholes in the rock mass – a process called rock grouting – thus sealing the rock fractures. Very little information and research has been on the subject of how the rock fracture orientation interact with the orientation and geometry of the grouting holes. The purpose of this thesis is to investigate whether or not it is possible and feasible to select a grout fan geometry that will have the most intersections with the rock fractures, based on fracture information gained in an early pre-investigation stage. The suitability of different grout fan geometries will be determined by analyzing the amount of fracture intersections that each geometry has in a discrete fracture network, generated based on data obtained from rock cores in the Stockholm Bypass project. The assumption is that more fracture intersections means a higher chance of sealing the rock mass. The results show that there is no clear difference in number of intersections between the analyzed grout fan geometries, indicating that focus should not be on analyzing the grout fans as whole units, but rather on the scale of individual grouting holes and fractures. This thesis also highlights the importance of monitoring according to the observational method. / Vatteninläckage i bergtunnlar är ett problem, speciellt inom tätbebyggda områden, eftersom en sänkt grundvattennivå kan orsaka sättningar i jordlagren och följaktligen skada infrastruktur. Dessutom kan ett för högt vatteninläckage vara ett incitament för miljödomstolen att stoppa tunneldrivningen i ett försök att skydda den allmänna miljön i dennas roll som ett nationalintresse.Vatteninträngning i tunnlar minskas normalt genom att injicera en blandning av vatten och mikrocement i borrhål lokaliserade i bergmassan – en process som kallas för sprickinjektering – och genom detta täta bergmassan. Idag finns mycket lite information tillgänglig om hur sprickors och injekteringshålens orienteringar interagerar med varandra.Syftet med denna uppsats är att undersöka huruvida det är genomförbart att i ett tidigt förundersökningsskede bestämma en skärmgeometri som kommer ha så många sprickskärningar som möjligt. Olika skärmgeometriers lämplighet bedömdes genom att analysera mängden sprickskärningar som varje geometri hade i ett diskret spricknätverk, baserat på indata från utvalda kärnborrningar från Förbifart Stockholm. Analysen utfördes under antagandet att fler sprickskärningar ger en större chans att täta berget.Resultaten visar att det inte finns en klar skillnad i antalen skärningar olika skärmgeometrier emellan, vilket indikerar att framtida fokus inte bör läggas på att analysera skärmgeometrier som enheter, utan snarare att analysen bör utföras på individuella injekteringshål och sprickor. Denna uppsats markerar också vikten av observationer under utförandet av berguttag och sprickinjektering i enlighet med observationsmetoden.

The Siljan Ring in Dalarna, Sweden is the site of the largest meteor impact crater in Europe and has long been a topic of discussion regarding methane production. However, the source of this methane and the timing of production in relation to the impact remain unclear. An outcrop of red Ordovician limestone preserved on the edge of a downfaulted zone encircling the crater’s central plateau is crosscut by fractures surrounded by pale-coloured reduction haloes within which precipitates can be observed. These haloes suggest interaction with a reducing agent mobilised within a fluid flow, of which methane would be a prime candidate. A field study was subsequently undertaken to establish the reaction whereby these haloes were formed, as well as the timing of their formation relative to the Siljan impact based upon petrological, geochemical, and structural data obtained in the field. Results from this study show that a methane-bearing hydrothermal fluid mobilised within the fractures has preserved the original mineralogy of the limestone within the reaction haloes whilst the country rock beyond was being oxidised. Pyrite is shown to be preserved within the pale reaction haloes, whilst its oxidation within the country rock is shown to be the source of the limestone’s distinct red colouring. Fracture and bedding orientation at the study site suggest the hydrothermal event to have been simultaneous with the meteor impact, with the fractures forming part of a wider complex network of impact features. Whilst mobilisation associated with the meteor impact is a likely cause of methane release, the exact source of the methane active at the study site is unclear.

Baggalútar are well-rounded spheroids that typically measures 16-18 mm in size and have a brownreddish appearance. They can be found in the Hvalfjörður bay in SW Iceland. There are manydescriptions in literature and on the internet that Baggalútar are volcanic spherulites formed by quartzor cristobalite spheres growing out of a common centre and there is also a broadly accepted consensusof this theory. However, despite this consensus that Baggalútar are volcanic spherulites there exist nodetailed investigation of their origin. The aim of the thesis is to investigate what Baggalútar is exactlyand how they form. This is achieved by using a combination of petrographic observations with apolarization microscope, mineral chemistry from electron microprobe analysis and measurements oftheir magnetic properties. The results are compared with different geological and anthropological spheroids, spherulites,nodules and concretions. The petrographic observations show that they predominantly consist of finegrained basaltic tephra (groundmass) together with zeolites infilling voids. Analyses of mineralchemistry indicate that the groundmass consists of augitic pyroxene, plagioclase, and two differentoxides where one classifies as titanomagnetite. The magnetic measurements support this by showing aCurie temperature at approximately 460-470 °C which is likely to be titano-magnetite. Although thedifferent geological and anthropological processes that typically results spheroidal shapes have somesimilarities that could explain the formation of baggalútar, most of these can be excluded for differentreasons. The internal textures of baggalútar strongly indicate that the shape is controlled by externalfactors, like weathering or erosion from beach outcrops. This could explain the spherical shape of asingle baggalút, but it fails to explain the spheroidal shapes of individual baggalútar joined together inclusters. / Baggalútar är väl rundade sfäroider som vanligtvis mäter 16–18 mm i storlek och har ett brunt rödaktigtutseende. De hittas i Hvalfjörðurbukten i SW Island. Det finns många beskrivningar i litteraturen ochpå internet som säger att Baggalútar är vulkaniska sfäruliter som bildas av kvarts- eller kristobalitsfärersom växer fram ur ett gemensamt centrum och det finns också en allmänt accepterad konsensus omdenna teori. Men trots denna konsensus om att Baggalútar är vulkaniska sfäruliter finns det ingendetaljerad undersökning av deras ursprung. Syftet med avhandlingen är att undersöka exakt vadBaggalútar är och hur de bildas. Detta uppnås genom att använda en kombination av petrografiskaobservationer med ett polarisationsmikroskop, mineralkemi från elektronmikrosondanalys ochmätningar av deras magnetiska egenskaper. Resultaten jämförs med olika geologiska och antropologiska sfäroider, sfäruliter, noduler ochkonkretioner. De petrografiska observationerna visar att de till övervägande del består av finkornigbasaltisk tefra (grundmassa) tillsammans med zeoliter som fyller ut tomrum. Analyser av mineralkemivisar att grundmassan består av augitisk pyroxen, plagioklas och två olika oxider där den enaklassificeras som titanomagnetit. De magnetiska mätningarna stödjer detta genom att visa en Curietemperatur på cirka 460–470 °C som sannolikt är titanomagnetit. Även om de olika geologiska ochantropologiska processerna som vanligtvis resulterar i sfäroida former har vissa likheter som kanförklara bildandet av baggalútar, kan de flesta av dessa uteslutas av olika anledningar. Baggalútars inretexturer indikerar starkt att formen styrs av yttre faktorer, som väderpåverkan eller erosion frånstrandhällar. Detta kan förklara den sfäriska formen av en enda baggalút, men det misslyckas med attförklara de sfäriska formerna av individuella baggalútar i sammanfogade kluster.

No description available.

Limestone is one of the main components of cement production. Limestone has been quarried in Skövde, Sweden, since the end of 19th century and Cementa AB has been operating the quarry since 1973. Aside from limestone, there are also Alum shale of Cambrian age, mudstones as well as bentonite layers of Ordovician age present in the quarry.  The production of cement evidently is important for Sweden’s infrastructure, and the quarry in Skövde is one of few known locations in the country with limestone with the right composition. Therefore, it is important to increase the knowledge regarding the character of the limestone to make accurate predictions for the future regarding the cement production. The geological knowledge of the area is already extensive; however, the aim of this thesis is to expand this knowledge further by constructing a 3D geological model. The data which has been used to construct the model are field observations, drill core data, chemical data, high-resolution pictures (photogrammetry) and resistivity measurements (field and samples). The resistivity measurements were done using the multiple gradient array, and apparent resistivity was inverted using Res2Dinv. The geological modelling was done using Leapfrog geo (© Seequent Systems, Incorporated). Two models have been proposed as a result of this project; one where high-grade limestone of lesser quality and whitestone has been regrouped with two other units (A) and one including all units (B). In the most recent drilling campaign, the nomenclature used to distinguish the units has been modified and does not differentiate high-grade limestone of lesser quality and whitestone from the rest. This affects coherence of the model and for this reason two models have been built. Both models show roughly flat lying units in the area of interest. Both low-grade limestone and lower waste stone units have consistent thickness in both models. The major difference between the models is how the high-grade limestone unit is modelled as a consequence of the additional units in model B. The result from the resistivity measurements shows unexpectedly low values, when compared to values from the literature as well as the measurements on hand samples from the quarry. The reason for these low values is still unclear, and therefore resistivity data has been used with caution. Considering this, it appears that resistivity measurements is not a suitable technique to characterize the subsurface in this particular area.  The models produced in this project provides information regarding thickness and extent of the units and overlying soil. As such, the new knowledge can be used to plan future prospecting campaigns, make projections, and estimates within current mining permits and evaluate how future mining can be conducted. / Kalksten är huvudkomponenten när det kommer till cementproduktion, vilken också behöver ha en specifik kemi för att vara lämplig att tillverka cement av. Kalksten av denna specifika kvalité har brutits i Skövde, Sverige, sedan slutet av 1800-talet. Cementproduktionen startade dock 1924 och Cementa köpte upp gruvan och fabriken 1973. I brottet finns förutom kalksten även alunskiffer, slamsten och bentonitlager. Vidare finns det två olika kvalitéer på kalkstenen, en med högt kalciumoxidvärde och en med lägre kalciumoxidvärde. Totalt representerar de formationer som finns i gruvan en 50 miljoner år lång historia av sedimentation. Cement utgör en grundläggande del för Sveriges infrastruktur, och brottet i Skövde är en av få platser i landet med en kalksten som har rätt kemi. Därmed är det viktigt att utöka kunskapen gällande karaktären på kalkstenslagren i och vid brottet för att kunna göra mer korrekta uppskattningar om Sveriges framtida cementproduktion. I dagsläget är kunskapen om geologin i och kring gruvan omfattande tack vare bland annat tidigare prospekteringskampanjer. Syftet med detta arbete är utöka den geologiska kunskapen ytterligare genom att konstruera en geologisk 3D modell. Denna geologiska 3D modell har skapats av data såsom borrhålsdata, resistivitetsmätningar samt drönarbilder för att bättre karakterisera de olika geologiska formationerna. På grund av att indelningen av de geologiska enheterna har varit olika mellan de tidigare prospekteringskampanjerna har två 3D modeller med olika upplösning skapats i stället för en. Modelleringen har fokuserats på ett område nordväst om nuvarande brytområde. Båda modellerna har sub-horisontella geologiska enheter inom intresseområdet. Vidare har modellerna liknande tjocklek och utbredning på enheterna i sin övre del, men skiljer sig åt längre ner. Detta på grund av att den ena modeller har flera enheter, vilket således även påverkar närliggande enheter. Dessa två modeller har utökat den geologiska kunskapen om området, till exempel de geologiska enheternas mäktighet och utbredning, samt hur mäktigt jordtäcket i området är. Denna nya kunskap kan användas för att planera och estimera hur brytning kan ske i framtiden. Det är dock viktigt att poängtera att det är modeller som skapats, vilka är antaganden av verkligheten.

Rapid technological advancements and growing environmental consciousness created a shifting dynamic of metal demand within the context of contemporary global challenges. The metals play a pivotal role in this transformation and remarkable surge in demand is expected. Mining districts such as the Kiruna area in northern Sweden, provide access to raw materials, assuring supply chain security, sustainability, and an environmentally friendly future. The district is part of the northern Norrbotten ore province, Sweden and is known for hosting the Kiruna-type iron oxide-apatite (IOA) deposits with associated magnetite-hematite-REE ores such as the Per Geijer deposits, and a range of other deposits, including the Viscaria Cu-(Fe-Zn), Pahtohavare Cu-Au and the Rakkurijärvi iron oxide-copper-gold (IOCG) deposits.  As the discoveries of significant near-surface deposits are declining, mining companies face a pivotal choice between pursuing resource extraction from lower-grade reserves or to focus on deeper exploration targets. The geological understanding of the subsurface decreases with increasing depth, and the reliance on geophysical techniques becomes more important in reducing the search space. Using geophysics to locate and understand elements of a mineral system requires a good understanding of the physical and chemical properties of the rocks that can be translated into geological implications. Mineral system knowledge and geological concepts can be translated into geological models that can be further used in geophysical inversions with the aim of improving targeting by iterative modeling. A geophysical inversion is in fact a realization of a physical property model, therefore the value added by the geophysical model is dependent of how well the relationship between the geology and its petrophysical signature is understood. The petrophysical characterization of geological environments offers the possibility to improve the understanding of geophysical responses, serving as a link in iterative geological-geophysical modeling.  The approach presented in the current study includes the building of three-dimensional lithological and structural framework models, and investigating the petrophysical footprint in connection with lithology, alteration, and rock fabric from the Kiruna mining district. Geological modeling and petrophysical characterization are important components within the comprehensive mineral system modeling framework and enhance geophysical investigations aimed at detecting and assessing iron oxide mineral systems. A rule-based hybrid implicit-explicit geological modeling technique proved to be useful in the integration of surface and subsurface data of the Kiruna mining district, and a structural framework and geological model was produced that provides insights into the relationship between lithological units and structures. Drill core observations indicate a competency contrast between lithological units confirming previous surface-based observations. Deposit scale structural analysis in connection with the geological models indicated the proximity of NW-SE to SW-NE trending brittle conjugate fault networks with iron-oxide apatite ore lenses, revealing juxtaposition of individual ore lenses. Complementing structural analysis and geological modeling, petrophysical characterization in connection with lithogeochemical, mineralogical, and textural investigations revealed that density and p-wave seismic velocity can be used as a general lithological indicator, while magnetic susceptibility is influenced by secondary processes. Heterogeneous strain accommodation by lithological units indicates a strong influence on density, seismic properties, and the ferromagnetic properties of the samples. Metasomatic processes alter the intrinsic properties of the samples by increasing or decreasing the physical properties of the rocks from the Kiruna area, by controlling the feldspar, mica, magnetite, and ferromagnesian mineral content. Nevertheless, an extensive sample population must be investigated to understand the large-scale effects. The present work serves as a foundation for quantitatively integrated exploration models that use geological models and petrophysical characterization as calibration tools to model mineral systems.

The Kiruna mining district, located in the northern Norrbotten ore province, Sweden, is a geologically and economically important area, being the type-locality for Kiruna iron oxide-apatite (IOA) deposits and also host to a variety of other deposits including syngenetic stratiform exhalative Cu-(Fe-Zn) (Viscaria, Eastern Pahtohavare), epigenetic stratabound Cu ± Au (Pahtohavare), and iron oxide-copper-gold (IOCG, Rakkurijärvi) deposits. However, the timing of IOA versus IOCG within the tectonic evolution is in question based on structural investigations showing Cu- and Fe-sulfides occur in late-orogenic structures. Here we use an established tectonic framework to constrain mineral systems (tectonic/thermal drives, metal and ligand sources, fluid pathways, traps, remobilization mechanisms) related to the early and late phases of the Svecokarelian orogeny in the Kiruna mining district. U-Pb zircon geochronology of intrusions in the district indicates a thermal drive was present during the early phase of the Svecokarelian orogeny from ca. 1920-1865 Ma, however remains enigmatic for the late Svecokarelian orogeny. Zircon grains from a magnetite-ilmenite gabbro yielded an age of 1881 ± 8 Ma, coeval with the Kiirunavaara IOA deposit and suggested to represent an important generation of mafic magmatism related to the ore. Lithogeochemistry of early bimodal Svecokarelian intrusions in the district indicates a within-plate to active continental margin environment with a volcanic arc affinity, pointing to a back arc environment. Epsilon Ndi and 87Sr/86Sri values calculated from the U-Pb ages for the igneous intrusions were compared to samples of ore-related alteration from epigenetic Pahtohavare and Rakkurijärvi deposits, district greenstone, and Archean samples. Results show that each deposit sourced Sr and Nd from a variety of rocks suggesting broad fluid transport. Each deposit has a distinct Sr mixing trend suggesting they formed from different ore-forming fluids and pathways. This is supported by new structural data that constrain the folding event and the ore-related quartz-carbonate-sulfide veins in the Pahtohavare area to a late orogenic timing, compared to the early orogenic timing of Rakkurijärvi. Sulfide trace element and sulfur isotope data from structurally constrained ores within the tectonic framework also record distinct characteristics between early and late deposits. However, remobilization of early Pahtohavare sulfides associated to an increase in Co content and heavier sulfur isotope compositions is recorded. The results of this study illustrate that using a structural framework approach to constrain the ingredients of mineral systems is a powerful strategy for interpreting ore deposit processes in tectonically complex terrains where both IOA and IOCG deposits occur.

Due to the increasing demand for processing low-grade ores, larger volumes of material are being processed. Therefore, the size of flotation equipment has significantly increased for the past decades. The studies related to scale-up are and will remain to be crucial in terms of designing larger flotation equipment. One of the most important factors for flotation scaling-up is the “flotation rate constant”. Hence, the main aim of this investigation was to understand the scale-up criteria when the size of different laboratory-scale cells increases, using the Outotec GTK LabCell®. This was done by assessing the influence of impeller speed, as a hydrodynamic variable, on the flotation performance. Recovery was found to increase with an increase in the cell area to rotor diameter ratio. Flotation rate and recovery increased with an increase in the impeller speed until a certain point that it eventually decreased for the 2 l and 7.5 l cells. For the 4 l cell, the flotation rate and recovery decreased with increasing the impeller speed. The impeller speed of 1200 rpm allowed a successful scale-up based on the flotation rate constants and recovery when increasing the size of the cells. Maintaining the impeller speeds constant at 1300 rpm increased the flotation rate constants and recovery when increasing the cell size from both the 2 and 4 l cells to the 7.5 l cell. A further increase in the impeller speed to 1400 rpm also produced the flotation rate constants and recovery to increase as the cell size increased from both the 2 and 4 l cells to the 7.5 l cell. However, when increasing the cell size from 2 l to 4 l, good results were also observed for all impeller speeds. The products concentrate seem to become finer when decreasing the cell size, with only a few exceptions. The recovery of particles larger than 38 μm was found to differ considerably less among the different scales.