This study describes what impact activity within Wifstas, Matfors,Grönstas and Nolbys water protection areas have on the quality of the drinkingwater. It considers the use of the area, environmentally dangerous activitiesin the past and present, the geology’s part, what harm hydroelectric power damsmay cause if they break and how climate change might affect the area in thefuture. It also takes into consideration activities outside the waterprotection areas which might have a suspected impact on the water quality. Theresults of the study are that pollution from infrastructure such as roads, orwastewater from treatment plants may cause occasional contamination of thedrinking water, foremost due to flooding. Substances in the ground which areoriginating from agriculture, forestry and environmentally dangerous activitiesin the past and present, may diffuse into the surface water or ground waterwith a possible negative effect on the drinking water today or in the future.The largest threats to the water quality is in case of an accident withpetroleum products from traffic or hydroelectric power dams. In a case of a dambreakage in Bergeforsen the water supply from Wifstas water source woulddecrease dramatically. The climate change might cause a change of use of theground area in the future.

Diss. Luleå : Luleå tekniska universitet, 2007. / Härtill 4 uppsatser.

This study focuses on the geology of the Nautanen area. It is part of the SGU-financed project, Metamorphic Map of Sweden, which aims to compile metamorphic data from Sweden and takes the form of a number of Bachelor and Master projects. The main metamorphic event in the Nautanen area is the Svecokarelian Orogeny (1.96 – 1.75 Ga). The samples are metamorphosed sedimentary and volcanic rocks, which were intruded by intermediate to mafic intrusions and a later granite intrusion. The supracrustal rocks are folded and the Nautanen Deformation Zone (NDZ) traverses the area in a NW to SE direction. Petrographic studies, XRF analysis and THERMOCALC were used to estimate pressure and temperature and to elucidate evidence of fluid mobility. The average pressure was assumed to be below 4 kbar because of the presence of andalusite. The lowest and highest temperatures for metamorphism were 474±43°C and 681±14°C, with highest temperatures recorded nearest to the granite intrusion. XRF analysis revealed high concentrations of Ba (up to 7000 ppm) in the NDZ. High concentrations of Ba, skarn formation and replacement of garnet by chlorite indicate fluid-controlled metamorphism in the NDZ. The increasing temperature towards the granite intrusion suggests regional or contact prograde metamorphism that need not be related to the NDZ. / Metamorphic Map of Sweden, SGU-project

This report aims to characterize the alteration styles and mineralization of the Zn-Pb-Ag Bronäs deposit, in the Sala area of the Bergslagen mining district, Sweden.  It presents data collected through 237m of lithological logging and subsequent lithogeochemical data, which, coupled with thin section and SEM analysis has led to the first geological descriptions of the rocks in the deposit.  The results are presented in the report through logs and a cross-section interpreted from these logs.  The Bronäs deposit, mined between 1945 and 1962, is a satellite deposit to the well-known Sala mine, and similarly to the Sala deposit, it is hosted within an extensive marble unit interbedded with layers of felsic volcaniclastic material.  The rocks in the area have first been dolomitized and then undergone regional metamorphism to greenschist facies at 1.87 Ga.  There is a large granitic batholith to the south and east of the deposit, and a thin porphyritic intrusion with a complex geometry closely spatially associated with the mineralization.  The marble unit is the host unit for the mineralization and is the most commonly occurring rock type in the study area.  It is commonly quite impure and variably skarn altered throughout, with common gangue minerals including serpentine, chlorite, tremolite, diopside and phlogopite.  The mineralized sections of the marble are spatially related to the skarn-rich areas of marble, and common sulphides include pyrite, galena and sphalerite. The interbedded volcaniclastic beds have a rhyolitic composition, and also contain Mg-silicates such as chlorite, tremolite and phlogopite, giving them a green colour too.  The contacts between volcaniclastic and marble beds is often marked by contact skarns.  The porphyritic intrusion has a granodioritic composition.  It exhibits chilled margins, and the contact between it and the marble is often marked by increased skarn alteration in the marble.  The feldspar crystals in the unit are zoned, with a white outer rim and a green to yellow sericitic core. The cross section shows that all the units are steeply dipping to the south-west, with steeply dipping stratabound lenses of mineralization in the marble, sub-parallel to the volcaniclastic beds in the north east.  The south-western part of the section is thick uninterrupted marble.  Lithogeochemical results have been divided into two groups – a distal group within this thick marble, and a proximal group close to the mineralization and volcaniclastic beds. The proximal zone is enriched in SiO2 and Al2O3 and depleted in FeO, MnO and MgO relative to the distal zone.  The Mn and Mg values are enriched when compared to regional levels however.  The proximal zone also contains more Pb, Zn, Ag, As and Sb than the distal zone, but contains lower amounts of Au and Cu than the distal zone.  There is one hotspot in the distal zone which contains high concentrations of Pb, Zn, Ag, Au, Cu and Sb. The chemical signature is similar to the mined ore at Sala.  The common occurrence of Fe, Mg and Mn-bearing skarn minerals near the mineralization suggests these elements should be higher in the mineralized zone, but skarn minerals are common throughout the study area, and the high levels of Si and Al in the mineralization zone could be diluting the other oxides.  The lenses of mineralization are closely spatially related to the porphyritic intrusion however the intrusion is relatively minor in terms of size and is younger and unaltered.  It could have followed an existing fault which was related to the mineralization though.  Various examples of sulphide replacement and retrograde alteration can be seen, such as galena replacing amphiboles and barite.  The similarity in mineralogy between regional metamorphic calc-silicates and ore-related skarn minerals makes it hard to differentiate between the two, however the presence of high temperature clinopyroxene indicates the deposit is likely a prograde metasomatic skarn deposit.  This is backed up by a similar calc-silicate assemblage, mineralization style and replacement textures to those associated with skarn deposits.  It is also spatially related to magmatism with mineralization occurring along lithological contacts.

Zirkon är ett mycket viktigt mineral inom geokronologin. Tack vare dess specifika kristallstruktur tassmå mängder uran och andra spårämnen upp av zirkonen vid dess bildning. Det är möjligt attbestämma en bergarts ålder genom att beräkna förhållandet mellan de radioaktiva ämnena och dessstabila slutprodukter som bildas hos zirkonen med tiden. Olika metoder och tekniker har sedandenna upptäckt utvecklats i snabb takt.Grötingengraniten har tidigare daterats med hjälp av TIMS till en ålder mellan 1,74 och 1,75 miljarderår. Denna datering har visats sig mycket osäker varför ett nytt försök till att bestämma dess ålder harplanerats in inom den närmsta framtiden. Innan man utför en sådan datering görs alltid enmikroskopisk förstudie där zirkonerna hos bergartsprovet avbildas med hjälp av olika sorterstekniker. De strukturer som kan identifieras hos zirkonerna kan sedan avslöja viktig information omvilka geologiska processer som verkat på bergarten.Syftet med denna studie var att extrahera ett antal zirkoner från Grötingengraniten för att undersökadess yttre morfologi och inre strukturer. Detta gjordes under både ett vanligt optiskt mikroskop ochett svepelektronmikroskop där BSE användes. Zirkonerna i provet uppvisade många olika strukturerfrån tydligt zonerade zirkoner till i stort sätt helt opåverkade och homogena zirkoner. Trots den storavariationen mellan strukturerna bland zirkonerna kan slutsatser dras om att denna granit troligtvisinte har påverkats av några postmagmatiska processer. Däremot syns tydliga tecken på attmagmatiska fluider funnits tillgängligt hos bergarten vid ett eller flera tillfällen. Många zirkoneruppvisar nämligen olika typer av flytstrukturer som bildats då fluider trängt in i zirkonen ochomfördelat den kemiska sammansättningen. Med tanke på att de flesta zirkoner i provet hadegenomgått en kraftig metamiktisering är det inte särskilt anmärkningsvärt att det tidigare försöket tillatt datera denna granit gav ett relativt dåligt resultat.

It takes a very long time for ionizing radiation of used nuclear fuel toreturn to a natural background level, for this reason one of the requirements for theselection of the location of a repository was that the environment as well people'shealth would be protected from the harmful effect of radioactivity. This requirementmeans that the waste must be isolated in a geological formation. In Sweden therepository will be built in the crystalline bedrock. The location for the Swedish nuclearfuel repository at nearly 500 meters depth at Forsmark in Östhammar was decided 3June 2009. The repository will be located at Söderviken, close to the Forsmarknuclear power plant in a 1.90 billion year old bedrock that will accommodate 12,000tons of spent nuclear fuel. The bedrock of Östhammar is a seismically quiet, howeverthere is a large system of fracture zones and fractures at the site considered to havebeen formed shortly after the ductile shear zone deformaton. The geology isdominated by medium grained metagranite with mafic intrusions. These rock volumeshave been subjected to metamorphism and ductile deformation at c. 1.85 Ga.The site investigations shown that the bedrock composition was asexpected, except for a few locations of a porous granite (episyenite) and a fracturedbedrock down to about 200 meters depth. This rock is relatively uncommon, but mayaffect the quality of the repository. Most episyenites are geographical associated tofractures and fracture zones, but there are exceptions where there are no distinctrelationships to the latter.

A geophysical investigation on the northern part of Utö was carried out between 2020 and 2021 to asses the extent of the iron ore (BIFs) and the iron bearing sulfides that have been surveyed and mined in the past. The survey using analog field equipment combined magnetometry, gravimetry, susceptibility, leveling, density, and thin-section microscopy. Magnetic measurement reduction method was done through SGU’s communicated advice and modeling software was used. Additionally, an in depth literature analysis was performed to understand the historical context of mine operations to aid interpretation. The results of the multidisciplinary analysis show a number of observations. The interpolated local magnetic anomaly and the gravimetric results fit well with current SGU magnetic and Bouguer anomaly maps. The crosscutting magnetic profile between Nyköpingsgruvan and Långgruvan remains anomalously high despite the volume of removed ore. Susceptibility results confirmed past reports of localities where iron bearing sulfides were found and provide evidence to early ore formation and fluid mobilization. The 2D Bouguer anomaly profile revealed deformation structures reported in literature and also suggests a possible volume of remaining iron ore. Rediscovered meta-tuffite and ignimbrite rock samples were collected and petrological analysis infers a high resolution lithology. Newly discovered literature and material of previous geophysical surveys determined iron ore depths up to 1000 meters. Despite the amount of survey data the results are concluded to be coarse in resolution but can be improved.

I denna uppsats kommer jag att studera landskapet i Krok By som ligger i den sydvästra delen av Nagu i den finska skärgården. De element som skapat Finland är att under en omvälvande tid som kallas lopiska orogenesen pressades vulkanbågar ihop mot den baltiska skölden och skapade den första berggrunden i östersjölandskapet. Därefter slets berggrunden åter isär innan den pressades ihop igen. Vidare kom en kontinent underifrån och splittrade Finlands sydspets. Detta är vad vi idag ser som Finlands skärgård. Vid den senaste istiden pressades jordskorpan som utgär Finland och norden ner. Vart efter isen smälte pågick en landhöjning som i sin tur kom att påverka landskapet. Hur har denna landhöjning påverkat landskapet i termer av jordarter, geomorfologi och sedementavlagring? Vilka spår har inlandsisen lämnat i landskapet? Finns det ett samband mellan landhöjning och människors val av att upprätta boplatser och bruksmark? I området Krok By kan man finna flera olika spår av inlandsisen i form av rundhällar och räfflor. Vidare finner man tydliga spår av ssedimentavlagringar som kan kopplas ihop med landhöjningen. Detta i sin tur kan kopplas ihop med människors möjligheter till bosättningar.

Porcelain is a translucent vitreous material that consists of clay (kaolin), feldspar and quartz which has been mixed and heated together to cause a metamorphic reaction. In Sweden, the Porcelain industry was established in 1726 at Rörstrands castle in Stockholm and is today one of the oldest industries in Europe to produce porcelain. Around the 1790’s Rörstrand got its feldspars and quartz from the Ytterby mine that was located at Resarö in Stockholm’s archipelago making the raw material somewhat easy to access. Rörstrand owned the mine in the 1850’s to 1926. During the time Ytterby mine was active, an amateur geologist by the name of Carl Axel Arrhenius, discovered an unusual black mineral in the quarry ore in 1787 which later led to the discovery of 8 new rare earth elements (REE) with the help of several Swedish chemists throughout time. These elements are Yttrium, Ytterbium, Gadolinium, Terbium, Thulium, Erbium, Holmium and scandium. This study will focus on the Swedish porcelain industry and how it has evolved throughout history and Rörstrand’s role in the discovery of yttrium.

<p>Gaut, S., 2005: Factors influencing microbiological quality of groundwater from potable water supply wells in Norwegian crystalline bedrock aquifers. Doktor Ingeniør thesis 2005:99. Department of Geology and Mineral Resources Engineering, NTNU, 153 pp and appendices.</p><p>Microbiological analyses from 195 Norwegian waterworks based on groundwater in bedrock have been examined to study the vulnerability of bedrock wells to microbiological contamination. Inspections have been carried out at 49 of the 195 waterworks to identify possible causes to the recorded microbiological contamination. It is found that groundwater derived from bedrock wells is susceptible to microbiological contamination and needs better protection. Seasonal variations in the water quality occur. Coliforms are mostly detected from June to September. <i>Cryptosporidium</i>, but not <i>Giardia</i>, is detected in the groundwater from three of twenty waterworks. The microbiological water quality is correlated to (i) wellhead completion (including the well casing), (ii) type and thickness of superficial deposits, (iii) land use and contamination sources and (iv) distance from wells to running water. Recommended wellhead completion includes a well-house and a casing of at least 5.5 m, rising 40-50 cm above ground. The gap between casing and bedrock should be sealed. Wells are least vulnerable to microbiological contamination when the superficial deposits are > 2.5 m thick and the wells are located > 100 m from farmland and not within 75-125 m of running water. Variations in parameters, such as colour, turbidity, and iron, and high levels of total organic carbon can indicate that the aquifer or the well is vulnerable to microbiological contamination. Vulnerability mapping combined with a hygienic evaluation of the well area and delineation of protection zones based on simple analytical methods is suggested as a method to protect Norwegian bedrock wells.</p>