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Geological factors affecting the channel type of Bjur River in Västerbotten County : A study concerning the connection between surficial geology, landforms, slope and different hydrological process domains in a stream catchment above the highest shorelineSkog, Emma January 2019 (has links)
Process domains categorizes sections of streams according to its local dominant processes. These processes often reflect on the local ecology and the streams appearance. But the underlying reason why these different process domains are formed are still not completely certain. In this study the distribution of the process domains: lakes, rapids and slow-flowing reaches in the Bjur River catchment were compared to the geological factors of slope, surficial geology and landforms to see if any connections could be found. The possibility of using GIS (geographic information systems) and remote data to distinguish these stream types and to connect them to the different studied geological factors were also examined. The hypothesis for this study is that the geological factors of slope, surficial geology and landforms all should have an influence over the distribution of the process domains in Bjur River. The analysis was executed through map-studies in ArcGIS and statistical analysis in Excel. All process domains showed statistical significance towards the studied geological factors. The slope was generally steeper in the rapids than in slow-flowing reaches and lakes. The surficial geology displayed more fine-grained sediment (peat) in proximity to lakes and slow-flowing reaches whilst till was more abundant close to rapids. Hilly moraine landscapes were most common around lakes, while rapids displayed a high percentage of glacio-fluvially eroded area. Slow-flowing reaches also showed to have around 44% of its studied points around glacio-fluvially eroded area, and 43% at areas without any major landforms. Even if the statistical analysis and figures display a difference between the different process domains, it is still difficult to say which of these geological factors that plays the most crucial role for their development. However, by using remote data and through studies over slope, adjacent surficial geology and landforms the different process domains can be differentiated from one another.
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Exploring an emerging land use conflict: GIS based site selection for expanding forests in DenmarkFeinberg, Marc January 2019 (has links)
The predominant land use in Denmark is agriculture, which has had negative effects on the aquatic environment, bothmarine and freshwater, due to excess nutrient runoff and resulting eutrophication. The current condition does not fullfillthe European Water Framework Directive’s goal of ‘Good ecological condition’ in all aquatic environments. InDenmark, forests only account for a small proportion of the land use, and despite an increase over the past twocenturies, the currently small forested area has had negative consequences for biodiversity since a majority of thespecies in Denmark are dependent on forests for habitat. The current efforts do not meet Denmark’s commitment tofulfill the United Nations Convention on Biological diversity. Similar to other countries, Denmark is obligated to reduceits carbon dioxide emissions according to the Paris agreement, with reduction goals of 40 % in 2030 and 80-95% in2050. The aim of the present thesis, is to assess whether reforestation on agricultural land can ensure that Denmarkreaches the international obligations for water quality and biodiversity at the same time as reducing climate impact byincreasing carbon sequestration, without significant land use conflict between agriculture and forest.This aim is pursued through an analysis of spatial data using a Geographical Information System, where threescenarios are created to assess differences in policy priorities.Based on the result of the spatial analysis, carbon sequestration estimates are calculated to assess the extent towhich forests could contribute to reducing the Danish climate impact, by increasing carbon sequestration. Theparameters used in the spatial analysis were found through a literature review, and the data for the spatial analysis wereaccessed in official and university databases.The main findings of the spatial analysis suggest that the areas with the highest potential agricultural value andthe areas with the highest potential for forest ecosystem services are not overlapping to a significant degree. Thisimplies that the areas that would have the highest levels of trade-offs between these goals when transitioning to forest,can continue the current land use without being needed for reforestation. The areas where agricultural value is low, andwhere reforestation would provide high levels of forest ecosystem services, are best suited for land use change. Theseareas were found to cover a substantial part of the study area, varying depending on three different scenarios, and areestimated to have the potential to contribute greatly to Denmark’s international commitments for water quality andbiodiversity. The carbon sequestration estimates show that if an area of approximately 7 % of Zealand was reforested,the sequestered amounts of carbon dioxide would correspond to a large portion of the emissions reductions necessary tofulfill Denmark’s obligations in the Paris Agreement.
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Reviewing environmental rebound effects from peer-to-peer boat sharing in FinlandWarmington-Lundström, Jon January 2019 (has links)
The world crucially needs to reduce the level of emissions being released in the environment in order to combat climate change. With the global population increasing and economies continuing to grow, the circular economy has been heralded by many as the potential solution to economic prosperity whilst also reducing primary resource use and emissions. However, the existence of environmental rebound effect has the potential to severely limit the emission reductions of the circular economy by increasing consumption elsewhere. This paper focuses on the definition of economic rebound effect and on its impact on a peer-to-peer boat sharing platform in Finland. A survey completed by users of the platform allowed for the quantitative analysis of environmental rebound effect experienced by the users and also provide insight into the consumption behaviour that created the most negative consequences. Rebound was experienced by almost all users with almost a third of users experiencing a backfire in which their overall emissions increased as a result of consumption made possible by the economic benefits of shared access. Primary production and the substitution of air travel for the leasing of a boat created large reductions in emissions, however, this was counteracted by increases in personal use and increased air travel by others. This real-life study of environmental rebound effect shows both its existence and impact on the peer-to-peer sharing of boats in Finland.
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Can Development of a Morphological Identification Key Simplify Determinations of Early Paleogene Dinoflagellate cysts? : Application to the Eocene of the Aquitaine Basin, Southwestern France, with Xper3 / Kan utveckling av en morfologisk identifieringsnyckelförenkla genusbestämning av cystor av dinoflagellaterfrån tidig Paleogen? : Tillämpning på Aquitainebassängenfrån Eocen, sydvästra Frankrike, med Xper3Carlsson, Veronica January 2019 (has links)
Knowing the taxonomy of unicellular dinoflagellate cysts is important in reconstructing paleoenvironments, paleoclimatology and paleobathymetry. Different dinoflagellates tend to prefer different depths, salinity levels and climate. Species of dinocysts only occur during a certain interval in the geological record and are therefore an important tool for dating sediments. Biostratigraphic research uses age determination of sediments depending on first and last occurrences of different species, or co-occurrences of several species. However, it can be rather time consuming and difficult to identify dinoflagellate cysts for people that are not experts in this field. In an attempt to resolve this, a database was created for 145 genera of dinoflagellate cysts existing during Palaeocene and Eocene in the online accessible program Xper3. Morphological criteria or “descriptors” were added along with describing “states”. The number ofmorphological descriptors chosen were 13, with 3 to 15 states for each descriptor.Each genus was described in a matrix and was given one or more unique states for each descriptor, which were defined from the literature by original morphological descriptions of dinocyst genera and photographs of holotypes. A morphological identification key was automatically created in Xper3 from this database, which enabled identification of genera by choosing unique states that were visible for the dinocysts being analysed.A test using photographs with different levels of preservation of dinoflagellate cysts of Eocene age of Aquitaine basin was undertaken in order to assess the reliability of the morphological identification key. The aim was also to see which morphological criteria were more common and how many descriptors and states were needed to reach an end-result of 5 remaining genera, including the correct genus.Errors that were caused in the identification key were immediately reviewed and re-tested. In 38 of 43 tries, a maximum of five genera were remaining, with the correct genus included. This confirmed that the identification key worked relatively well.Another test demonstrated how the identification key worked for identifying dinocysts with an optical microscope in unknown samples, which are photographed and published in the present report, along with data showing how many descriptors and states were used, remaining genera and which states were chosen for each genus.In general, only 1-8 descriptors were necessary and 5 the most common number used. The morphological character (state) “type of ornamentation” was the most widely used followed by “distribution of ornamentation”, “shape of the cyst” and “size of the ornamentation”. However, the archeopyle (excystment opening), was not always visible in the dinocysts, but is still considered a key morphological descriptor. / Dinoflagellater är en typ av mikroskopiska plankton som kan bilda så kallade cystor eller vilosporer för att skydda sig vid kritiska miljöförändringar. Dessa cystor kan ligga vilandes i sediment under en längre tid. Det är också dessa cystor som bevaras som fossil. Eftersom det finns en sådan hög mångfald av dinoflagellatcystor i fossila sediment, liksom att de mikroskopiska, existerar över stora delar av jorden samt att de har en snabb evolution, så används de ofta till att datera sediment inom biostratigrafi.För att kunna datera sediment med hjälp av dinoflagellatcystor, krävs det att man kan identifiera de olika arterna och veta i vilken tidsålder de existerade. Att klassificera dinoflagellatcystor kan därför vara mycket svårt och ta en hel del tid om man inte är någon expert. I denna studie har därför en databas och identifieringsnyckel skapats i ett onlinebaserat dataprogram kallat Xper3. Xper3 är primärt riktat till att hjälpa personer med grundläggande kunskaper i att beskriva utseendemässiga karaktärer hos olika typer av mikrofossil, inklusive dinoflagellatcystor.I denna identifieringsnyckel använde jag mig av 145 olika dinoflagellatsläkten vilka alla existerade någon gång under tidig Paleogen, dvs hela Paleocen och/eller Eocen (66–34 miljoner år sedan). Dessutom användes 13 olika morfologiska beskrivningar ”descriptors” med 3–15 olika svar ”states” per beskrivning.Målet är att få en identifieringsnyckel som unikt kan identifiera olika typer av dinoflagellatcystor på genusnivå, med ett förslag på maximalt fem återstående släkten (genera). Studien undersökte även vilka morfologiska beskrivningar som är mest användbara och hur många olika typer av beskrivningar som behövs för att analysera dinoflagellatcystor.För att testa om identifieringsnyckeln fungerade, användes olika typer av kända och okända dino-flagellatcystor i ett så kallat ”Test 1: Kända dinoflagellatcystor” och ”Test 2: Okända dinoflagellat-cystor.I det första testet, ”Test 1”, grupperades kända dinoflagellatcystor i olika typer av bevarande tillstånd så som ”välbevarade”, ”tveksamt bevarande” och ”väldigt dåligt bevarade” dinoflagellat-cystor. Detta test förde statistik på hur många släkten av förslag som kom upp i slutändan och vilka morfologiska beskrivningar som användes mest och hur många olika beskrivningar som behövdes.Det andra testet, ”Test 2”, undersökte hur denna identifieringsnyckel fungerade att analysera dinoflagellatcystor från okända prover under mikroskop. Fotograferade dinoflagellatcystor presente-rades i denna rapport tillsammans med detaljer på hur de hade identifierats.I de flesta fallen, kunde identifieringsnyckeln ge ett förslag på maximalt fem återstående släkten av dinoflagellatcystor, där det korrekta släktet var ett utav förslaget, vilket tyder på att identifierings-nyckeln fungerar. Den mest använda morfologiska beskrivningen var ”typ av ornament”, och antal morfologiska beskrivningar som behövdes var mellan ett till åtta, där fem var det antal beskrivningar som mest användes i att identifiera dinoflagellatcystor i identifieringsnyckeln.
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Social Life Cycle Assessment in the Textile Industry: a case study in a small companyGrönkvist, Sofia January 2019 (has links)
Investigations of the textile industry and apparel sector often reveal unethical behaviours towards workers and lack of transparency in the value chain. As consumers are getting more conscious and the external pressure and demand for more sustainable clothing increases, companies need to implement management systems to control their operations and ensure actions are socially responsible. The Social Life Cycle Assessment (S-LCA) methodology published by the United Nations Environment Programme in 2009 are suggested to measure positive and negative social impacts on stakeholders along a products entire life cycle, from cradle to grave. The methodology is still under development and no methods have yet been standardized or internationally recognized. To contribute to the development of the S-LCA and its practical use in real world situations, the present study aims to evaluate the applicability of existing methodologies and tools by applying them to a cotton shirt from a small company in Sweden. The case study was performed by conducting an S-LCA following the four phases: Goal and scope; Life Cycle Inventory; Life Cycle Impact Assessment and; Life Cycle Interpretation. Generic country-level data and organisation specific data were collected through questionnaires, document review and desktop screening, while two different assessment tools were tested for the different data types. For generic country-level data, a Social Hotspot Assessment framework developed for this study, was applied and evaluated. For organisation specific data the existing Subcategory Assessment Method (SAM) was subject for feasibility evaluation. The S-LCA conduction involved several application issues that affect the perceived applicability and feasibility of the methods. Problems identified relate to the definition of system boundaries and uncertainties in the choice of appropriate and relevant indicators. The major problems refer to data collection both in terms of availability and quality issues both with regards to the inventory and assessment phase. Further, in the assessment and interpretation phase uncertainties regarding assessment criteria’s and aggregation of results evolved when using the framework for identifying hotspots, affecting the reliability of the results. Despite the identified issues, it is evident that it is possible to conduct and finalise a Social Hotspot Assessment using the methodology. However, based on the reliability issues of the results and the effort it requires, it is concluded that the applied framework is not feasible for smaller clothing companies with limited resources. The assessment of organisation specific data by applying SAM, is considered incomplete and identified issues reflect the incompatibility of the method and are thus not considered applicable or feasible for smaller companies.
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Avalanche Visualisation Using Satellite RadarWidforss, Aron January 2019 (has links)
Avalanche forecasters need precise knowledge about avalanche activity in large remote areas. Manual methods for gathering this data have scalability issues. Synthetic aperture radar satellites may provide much needed complementary data. This report describes Avanor, a system presenting change detection images of such satellite data in a web map client. Field validation suggests that the data in Avanor show at least 75 percent of the largest avalanches in Scandinavia with some small avalanches visible as well. / Lavinprognosmakare är i stort behov av detaljerad data gällande lavinaktivitet i stora och avlägsna områden. Manuella metoder för observation är svåra att skala upp, och rymdbaserad syntetisk aperturradar kan tillhandahålla ett välbehövt komplement till existerande datainsamling. Den här rapporten beskriver Avanor, en mjukvaruplattform som visualiserar förändringsbilder av sådan radardata i en webbkarta. Fältvalidering visar att datan som presenteras i Avanor kan synliggöra minst 75 procent av de största lavinerna i Skandinavien och även vissa mindre laviner.
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En analys av mesostrukturella variationer i Stockholmslera med avseende på vattenkvot, konflytgräns och lerhalt / An Analysis of Meso-Structural Variations in Stockholm Clay with Respect to Water Content, Liquid Limit and Clay ContentFlorén, Tove January 2019 (has links)
När geotekniska laborationsanalyser utförs undersöks ofta kolvprover från olika djup som får representera marken vid det djupet provet är taget. I ett homogent lerskikt kan denna punkt antas vara representativ. I en icke-homogen lerjord, till exempel i varvig lera, skulle denna punkt kunna infalla i en icke-representativ variation. För att ta reda på om dessa strukturella variationer påverkar en leras mekaniska egenskaper har i denna studie lerprover från olika platser i Stockholms län analyserats. Genom laborationsundersökningar har lerornas vattenkvot, konflytgräns och lerhalt bestämts och jämförts med varandra. Konflytgränsen definieras som vattenkvoten då en lera går från plastisk konsistens till flytande konsistens och bestäms i denna studie med fallkonmetoden (Axelsson & Mattsson, 2016). Vattenkvoten anger förhållandet mellan jordens fasta massa och vattnets massa och bestäms genom vägning och torkning i ugn (Larsson, 2008). Lerhalten i ett jordprov bestäms genom en hydrometeranalys som anger mängden lera i förhållande till övriga kornstorlekar i provet. Proverna som har studerats i denna studie var av varierande kvalitet med avseende på varvighet och både glaciala och post-glaciala leror har undersökts. Resultatet visar att det är svårt att studera skillnader mellan ljusa och mörka variationer i leror som inte har en tydlig varvighet och att stora variationer förekommer i de undersökta parametrarna för mörka såväl som ljusa skikt. / When geotechnical laboratorial analyzes are executed, piston samples from different earth depths are commonly used. These samples will represent the soil at the given depth. The point at which the sample is taken could be seen as representative in a homogenous layer of clay but in an inhomogeneous layer, such as a varved glacial clay, this point could occur in a variation that is not representative for the whole layer. To find out if these structural variations will affect a clays mechanical properties clays from the Stockholm region have been analyzed. The clays water content, liquid limit and clay content has been determined through laboratorial analyzes and then compared with each other. The liquid limit is defined as the water content when a clay is transitioning from plastic to liquid consistency and is determined by the fall-cone method (Axelsson & Mattsson, 2016). The water content is determined through drying in a drying oven and gives the relationship between the soil’s solid mass and the mass of the water (Larsson, 2008). The clay content in a soil sample is determined through hydrometer analysis and gives a value on the amount of clay in relationship to other fractions. The samples which have been studied were of different quality with respect to how distinguishable the varves were and both glacial and post-glacial clays have been analyzed. The result show that it is difficult to analyze differences between light and dark variations and varvs in clays which does not have distinct layering and that vast variations occur in all of the analyzed parameters for both dark and light variations.
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Jämförelse av portrycksmätning i Uppsalalera mellan portrycksmätare och dissipationstestAhlgren Mattsson, David January 2019 (has links)
Portrycket är en viktig parameter för att bestämma jordens egenskaper, såsom dränering, permeabilitet och stabilitet (då portrycket har en påverkan på den effektiva spänningen i jorden). Portrycket kan mätas med portrycksmätare men det kan även mätas under ett Cone penetrating test (CPT) med ett s.k. dissipationstest. Fördelar med ett dissipationstest jämfört med traditionell portrycksmätning skulle vara att det skulle spara tid och pengar, då man slipper trycka ner portrycksmätare och sedan vänta på att få portrycket ifrån dem, istället kan portrycket mätas under sondering med CPT.Detta självständiga arbete har som syfte att jämföra portrycksmätningar mellan portrycksmätning med BAT-spets och dissipationstest under CPT-sondering för att se hur bra mätvärden dissipationstester ger och om de eventuellt kan ersätta portrycksmätare. Fältförsöken av metoderna skedde i Uppsalalera, på en tomt i Kungsängen i Uppsala.Två stationer med BAT-spetsar på 5 meter, 7,5 meter och 10 meters djup sattes ner i leran. Sondering med CPT genomfördes sedan, där borren stoppades på samma djup som BAT-spetsarna. CPT:n stoppades på dessa djup i drygt 24 timmar, för att tillåta det generade portrycket som skapades när borren trycks ner i leran att skingras åt sidan. Jämviktsportrycket kommer vara det portryck som finns kvar efter att det generade portrycket har försvunnit. Portrycken från de två olika metoderna jämfördes sedan för att se hur nära dissipationstestet kommer värdena från portrycksmätningen med BAT-spetsarna.Resultatet av dissipationstesterna blev att inga av dem nådde referensvärdena från BAT-spetsarna efter 24 timmar. Beroende på användningsklass ligger dissipationstesterna inom den tillåtna minsta noggrannheten. Dissipationstest är antagligen inte så praktiskt tillämpbart i jordar med låg permeabilitet. / The pore pressure is an important parameter for determining the properties of thesoil, such as drainage, permeability and stability (since the pore pressure has aneffect on the effective stress in the soil). The pore pressure can be measured withpore pressure gauges but it can also be measured during a Cone penetration test(CPT) with a dissipation test. Advantages of a dissipation test compared tomeasurement with traditional pore pressure gauges would be that it would save timeand money, since you don’t have to press down pore pressure gauges and then waitto get the pore pressure from them, instead the pore pressure can be measuredduring probing with CPT.The purpose of this project is to compare pore pressure measurements betweenpore pressure measurements with BAT-tips and dissipation test during CPT probing,to see how good measured values the dissipation tests will provide and if theyeventually can supersede pore pressure gauges for pore pressure measurements.The field tests of the methods were done in Uppsala clay, on a site in Kungsängen inUppsala.Two stations with BAT-tips at 5 meters, 7.5 meters and 10 meters depth wereinstalled in the clay. Probing with CPT was then carried out, by stopping the CPT atthe same depth as the BAT-tips. Measurements with the CPT were done at thesedepths for just over 24 hours, to allow the generated excess pore pressure createdwhen the cone is pushed into the clay to disperse to the sides. The equilibrium porepressure is the pore pressure that remains after the generated pore pressure hasdissipated. The pore pressure from the two different methods was then compared tosee how close the dissipation test results were to the values from the pore pressuremeasurements with the BAT tips.The result of the dissipation tests was that none of them reached the referencevalues from the BAT-tips after 24 hours. Depending on the chosen application class,the dissipation tests are within the permitted minimum accuracy. Dissipation tests areprobably not practically applicable to soils with low permeability.
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Vattentillgång, vattenanvändning och inställning till återanvändning av renat avloppsvatten på en ö i skärgården – en fallstudie om MöjaAdelsköld, Signe, Ilao Åström, Sheryl January 2019 (has links)
Befintliga klimatscenarier visar att vi i framtiden kommer att få längre torrperioder och intensivare nederbörd, vilket ökar sårbarheten i våra system för dricksvattenförsörjning och avloppshantering. Öar är känsliga för kommande klimatförändringar då de har små vattentillgångar och sällan har kommunal vattenförsörjning. Dagens vattensystem är linjära, där renat avloppsvatten återförs direkt till naturen. För att få en bärkraftig avloppshantering kan en vattenanvändning införas som efterliknar den hydrologiska cykeln. Syftet med studien är att undersöka ön Möjas vattentillgång, vatten- och avloppssystem, inställning till att återanvända avloppsvatten, samt om cirkulärt vattenbruk är ett hållbart system. Genom semistrukturerade intervjuer, enkäter, litteraturstudier och fältstudier på ön har data samlats in och analyserats. Resultaten visar att Möjas befolkning använder mindre vatten per person och dygn än den genomsnittlige svensken. Inställningen till att återanvända renat avloppsvatten varierar, med lägst acceptans för återanvändning av svartvatten. Studien visar att cirkulärt vattenbruk är möjligt då ett sådant system redan har installerats på ön. Resultaten tyder på att öbor generellt hushåller med sina vattenresurser, samt att en tveksam inställning till att återanvända svartvatten kan bero på den så kallade äcklighetsfaktorn. Trots en varierande acceptans för att återanvända vatten bör fler cirkulära vattensystem kunna införas på ön, vilket ger Möja en mer bärkraftig hantering av sitt avloppsvatten. / Existing climate scenarios show that in the future we will have longer dry periods and more intense precipitation, which increases the vulnerability of our drinking water and wastewater management systems. Islands are sensitive to future climate change due to limited water resources and the fact that they rarely have a water supply from the municipality. Today's water systems are linear, where purified wastewater is returned directly to nature. In order to obtain a sustainable sewage treatment, the usage and treatment of water need to mimic the hydrological cycle. The purpose of this thesis is to investigate the island's water supply, water and sewage systems, the attitude towards reuse of wastewater, and whether a circular model of using water is a sustainable system. Through semi-structured interviews, surveys, literature studies and field studies on the island, data has been collected and analysed. The results show that Möja's population uses less water per person and day than the average Swede. The attitude towards reusing purified wastewater varies, with the lowest acceptance for the reuse of black water. The study shows that a circular model of using water is possible since such a system has already been installed on the island. The results indicate that islanders generally are more cautious with water resources and there is an uncertain attitude to reusing black water, which may depend on the so-called yuck-factor. Despite a varying acceptance for reuse of purified wastewater, circular water systems can be introduced on the island, which gives the population a more sustainable management of its wastewater.
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Interaction Between Different Magma Types in the Reyðarártindur Magma Chamber, SE Iceland / Interaktion mellan olika magmatyper i magmakammaren Reyðarártindur, sydöstra IslandRousku, Sabine January 2019 (has links)
Southeast Iceland exhibits a granophyre pluton called Reyðarártindur, which has never been described in detail before. The Reyðarártindur magma chamber formed 7.30 ± 0.06 Ma ago (Padilla, 2015). Glacial and coastal erosion expose the pluton, and a river cuts through the pluton roof and walls, revealing interaction between different blob-like structures of magma. The formation of magma chambers can take a very long time, it is therefore likely for several different magmas to interact. Incremental formation of different magma batches give rise to mixing and mingling in magma chambers. To understand when the magma mixing was initiated and the mechanisms controlling it, descriptive analysis were made to obtain textural properties of collected rock samples from the field. The purpose for this thesis study was to examine if there is a frequency size and shape distribution of the magma blobs and if the different magma blobs are systematically distributed across the river. Previous studies have inferred conduit locations and magma mixing processes through similar methods. Extensive field studies have provided all samples for this thesis. Five distinct, magma types were described and found to be interacting. There was one ‘host magma’ which the other four different magma types are exposed as ‘blobs’ within. The statistical analysis involved mapping the blob-like structures from photos taken with an Unmanned Aerial System (URA; drone), using the software Inkscape. The data and measurements for the blobs was collected and summarized in ImageJ. The data was then statistically analyzed in Excel, illustrating the frequency of the magma blob’s size and shape distribution in selected parts of the river. The results of the statistical analysis of the magma blobs showed that ~80 % of the blobs existed in a size interval between 0 – 0.1 m2 . This thesis provides a discussion about the implications of the blob distributions for magma chamber recharge and processes within this section of the magma chamber. The shape distribution analysis showed an indication for all the blobs to be more rounded and equant. This suggest that the magma mixing event probably happened at the same time, during a liquid phase. / På sydöstra Island återfinns en granofyrisk pluton kallad Reyðarártindur. Det är en magmakammare som aldrig tidigare blivit beskriven i detalj. Magmakammaren bildades för 7,30 ± 0,06 Ma sedan (Padilla, 2015). Plutonen har blivit exponerad genom glacial- och fluvial erosion samt att en flod skär igenom plutonens tak och väggar. Den eroderande floden exponerar olika fläckliknande strukturer av magmainteraktioner. Ett gradvist bildande av olika magmasatser har över lång tid gett upphov till en blandning i magmakammaren. För att förstå när magmablandningen initierades och mekanismerna bakom fenomenet, har en beskrivande analys gjorts för att ta reda på texturella egenskaper av insamlade bergartsprover från fält. Syftet med denna studie var att undersöka om det fanns en storleks- och formdistribuering av magmafläckarna samt om de olika magmafläckarna är systematiskt distribuerade i flodbädden. Tidigare studier har antytt var undersökta magmakanalsystemen kan finnas samt hur blandningsprocesser för magma går till med hjälp av liknande metoder. Redan genomförda fältstudier har samlat in allt råmaterial som ligger till grund för denna studie. Fem olika magmatyper har beskrivits och påvisades interagera. Det fanns en ”värdmagma” som de andra fyra magmatyperna var exponerade som fläckar i. De statistiska analyserna inkluderade kartering av de fläckliknande magmaformerna baserat på foton tagna med hjälp av en drönare. Tre olika mjukvaror användes för att samla in, mäta och analysera data; Inkscape, Image J och Excel. Resultaten från den statistiska analysen visade att ungefär 80 % av alla fläckar existerade inom ett areaintervall mellan 0 – 0,1 m2 . Denna studie innehåller en diskussion om implikationerna av magmafläckarnas distribution med avseende på magmaomladdning och -processer inuti denna sektion av magmakammaren. Den generella formdistributionen visade en indikation för att alla fläckar tenderar att vara mer rundade och kvadratiska. Detta antyder att magmans blandningsförlopp troligtvis inträffade vid ungefär samma tidpunkt, under en flytande fas.
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