Eclogites are important in order to understand orogenic processes, since their presence indicates high-pressure metamorphism. In northern Jämtland, Swedish Caledonides, eclogites have been found at several places in the Seve Nappe Complex (SNC). The mountain Tjeliken in the Lower Seve Nappe is one of them. Dating relates the high-pressure metamorphism to the Late Ordovican subduction of the Baltoscandian margin during the closure of the Iapetus Ocean. In this study new P-T conditions are presented for the Tjeliken eclogite based on petrographical and geochemical studies of an eclogite sampled on the top of Tjeliken in summer 2010. Peak assemblage consists of garnet + omphacite + phengite + quartz. New peak conditions are calculated to c. 2.7 GPa and 700°C. These P-T conditions are in the upper part of the quartz stability field, close to the quartz - coesite stability line. The new P-T conditions correspond well to other P-T calculations of eclogites in northern Jämtland and indicate a deep subduction of the Baltoscandian margin already in the Late Ordovician.

Sala är beläget i Bergslagen och bergarterna hör därmed till den svekofenniska berggrunden. Berggrunden domineras av 1.9-1.87 Ga sedimentära-, vulkaniska- och metamorfa bergarter. Vad man vet idag har metamorfosen i Bergslagen skett vid temperaturer på 500-650 ºC och på ett djup av 10-15 km. Salas berggrund är till stor del uppbyggd av karbonater, hälleflinta, kvartsdioritporfyrit, granofyr och granit. Karbonatstenen är till största delen magnesiumrik och övervägande dolomitisk till sammansättningen. Ett mer än 300 meter mäktigt dolomitlager innehåller Sala gruvas zink- och silvermalmer. I sydost begränsas dolomiten av graniter och i väster av hälleflintor. Sala gruvas primära malmmineral är järnrik zinkblände, magnetkis, blyglans, magnetit och pyrit. Viktiga associations- och spårmineral är bland annat kopparkis, gudmundit, molybdenglans, boulangerit, diaforit, freibergit och mineral tillhörande Ag-Hg-Sb systemet. Sju polerprover från Salaområdet analyserades med hjälp av reflektionsmikroskop och två dessutom med elektronmikrosond. Blyglans detekterades i alla prover. Zinkblände, pyrit och tetrahedrit återfanns i 6 av 7 prover, rent silver hittades i ett prov från Stenhavet och magnetkis hittades i alla prover från Stensbotten. Kopparkis, AgHg-amlagam och magnetit kunde ses i cirka hälften av proverna. Gudmundit återfanns i två av proverna plockade vid Stensbotten och två av proverna tros innehålla molybdenglans. Ett av proverna undersökt med WDS-analys innehåller ren antimon samt tre andra antimon- och silvermineral. Metamorf påverkan har diskuterats från de texturella sambanden.

Metaller och gruvdrift är ett ständigt aktuellt ämne. Återanvändning av metaller blir allt viktigare då metaller betraktas som en ändlig resurs. Men är de verkligen det, och i sådana fall: ur vilket perspektiv? Arbetet behandlar bildningsprocesser för några av våra viktigaste metaller - guld, järn, nickel och koppar - samt en handfull sällsynta metaller vars användning ökat: indium, gallium och germanium. Arbetet börjar med att kortfattat diskutera begreppen malmer och mineral. Därefter beskrivs de processer som enligt rådande vetenskaplig teori ligger till grund för de viktigaste av dessa malmförekomster. Där behandlas även tidsbegreppet för malmbildande processer. Beräknade tillgångar på dessa metaller i dagsläget, samt beräknade reserver tas också upp. Vidare diskuteras prisutvecklingen på dessa metaller och avslutningsvis förs ett resonemang kring prisutveckling med fokus på den globala marknaden och tillväxtekonomierna i Kina, Ryssland, Indien och Brasilien samt andra mindre men likväl växande ekonomier i världen.

Bakgrundshalter för olika metaller i svenska sjöar och vattendrag stämmer inte alltid överens med geologin i lokala områden, som kan ha anrikats många gånger högre än beräknade halter i jordskorpan. Detta är fallet i Barseleområdet, norra Sverige där Agnico Eagle genomför undersökningsarbeten med fokus på guld. Syftet med arbetet är att undersöka vad som anses vara naturliga halter av metaller i området med avseende på lokal geologi och jämföra dessa med bedömda bakgrundshalter. Fokus ligger på metallerna arsenik, antimon, bly och zink där även dess geokemiska beteende undersöks. Vattendata från vattendrag och sjöar från tio lokaler i området kring fyndigheten under perioden 2001–2016 har bearbetats. Analyserna har gjorts med analyspaket V2 (grundämnen i sötvatten). Bakgrundshalter har erhållits från SLU och Sveriges miljöinstitut som jämförts med vattendata från området. Resultaten visar att arsenik och antimon har genomgående högre halter än beräknade bakgrundshalter, där antimon, bly och zink generellt ligger i linje med bakgrundshalterna beroende på klassning av vattnet. Faktorer som pH, hydrologiska förhållanden samt löslighet och rörlighet i vatten visar sig ha stor påverkan på om halterna av metaller kommer överskrida bakgrundshalterna. Adsorption till järnoxider är ett exempel på en faktor som påverkar metallers rörlighet i vatten, och därmed om de kommer anrikas eller inte. / The levels of metals measured in individual Swedish lakes and waterways (local scale) do not always correspond to levels expected from knowledge of the underlying geology (regional scale), and in some cases can be orders of magnitude higher than expected. This is the case in the Barsele area, northern Sweden, where Agnico Eagle are exploring for gold. The purpose of this work is to investigate the natural levels of metals in waters with regard to local geology in the area, and compare these with calculated background levels. The study focuses on the metals arsenic, antimony, lead and zinc, and their geochemical behavior. Water data from ten sites during 2001–2016 have been studied. The analyzes were carried out with V2 analyzing package. Background levels were obtained from SLU and Sweden's environmental institute, which have been compared with water data from the area. The results show that arsenic and antimony have consistently higher levels than calculated background levels, while levels of lead and zinc generally correspond to background levels, depending on the classification of the water. Factors such as pH, hydrological conditions, and solubility and mobility in water have a major influence on whether or not the levels of metals exceed the calculated background levels. Adsorption to iron oxides is an example of a factor that decreases the mobility of metals in water.

The well-known Skellefte Ore District, northern Sweden, hosts a large number of massive sulphide deposits, a few porphyry-type-deposits and a number of gold deposits in different geological settings. Southwest of this district a new ore province, the so called Gold Line, is presently being uncovered. During the past decade a number of gold occurrences have been discovered in this area. Only one deposit is in production, the Svartliden gold deposit (2 Mton at 4.3 ppm Au). However, with regards to tonnage the Fäboliden gold deposit stands out with a known mineral resource of c. 16 Mton with 1.33 ppm Au. Additional 24.5 Mton with 1.5 ppm Au is indicated down to a depth of 350 m. The late- to post-orogenic, c. 1.81-1.77 Ga, Revsund granite constitutes the main rock type in the Fäboliden area and surrounds a narrow belt of metavolcanic rocks and metagreywackes. The metasedimentary rocks are strongly deformed, within a roughly N-S trending subvertical shear zone, with boudinaged competent horizons that indicate E-W shortening and a suggested dextral sense of shear within the shear zone. The mineralization at Fäboliden constitutes a 30-50 m wide, N-S striking, steeply dipping ore zone. The mineralization is commonly hosted in arsenopyrite-bearing quartz-veins, which parallel the main foliation, within the metagreywackes in the shear zone. The fine-grained (2-40 µm) gold is closely associated with arsenopyrite-löllingite and stibnite and found in fissures and as intergrowths in the arsenopyrite-löllingite. Gold is also seen as free grains in the silicate matrix of the metagreywacke host rock. Microprobe analysis shows that the gold occurs as electrum (Au:Ag 2:1). The proximal ore zone display enrichment in Ca, total S, As, Ag, Au, Sb, Sn, W, Pb, Bi, Cd, Se, and Hg, whereas K and Na are slightly depleted. The hydrothermal alteration assemblage in the proximal ore zone is diopside, calcic amphibole, biotite, and minor andalusite and tourmaline. This type of assemblage is commonly recognized in hypozonal orogenic gold deposits worldwide. The c. 1.3 km long ore body (lode) is steeply dipping and known to a depth of 150 m, with a few deeper boreholes indicating a continuation of the mineralization towards depth. The mineralization is also open towards north and south. The fabric that hosts the mineralization is also found in the outer margin of the surrounding Revsund granite. It is therefore suggested that at least the final stages of the gold mineralization are late- or post-orogenic in age, and the maximum age for the mineralization is constrained at c. 1.80 Ga (Revsund age). The mineralizing fluids were composed of CO2-CH4-H2S. Gold, arsenopyrite- löllingite, and graphite were precipitated from this fluid. The crystal structure of the graphite, enclosed in the gold related quartz veins, indicates a maximum temperature of 520-560ºC for the mineralizing event, temperature conditions equal to mid-amphibolite facies. These temperatures indicate pressure conditions of c. 4 kbar for the mineralizing event. During deformation mineralizing fluids are often concentrated into deformation zones. Therefore, the potential for economic mineralization in the Lycksele-Storuman region is regarded as very high since the initial results from this project have indicated the existence of several larger ductile to semi-ductile shear zones and accompanied silica alteration in the studied area. During 2004 the project strongly assisted in locating a new gold target in the Gold Line area. For more effective future exploration in this area a better understanding of the structural conditions and evolution is a key factor. / Godkänd; 2005; 20061214 (haneit)

The northern Norrbotten ore province is an intensely mineralised area and has traditionally been a very important mining district. It contains Fe, Cu-Au, Au, and Ag deposits ranging from world-class ore deposits to small and uneconomic ones (Martinsson 2004). The most important are the Kiruna and Malmberget iron ores and the Aitik Cu-Au deposit.The cross-discipline approach called geometallurgy connects two different but closely related areas in the mining industry, namely geology and mineral processing. It involves understanding and measurements of the ore properties significant for its successful processing. Geometallurgy takes both the geological and mineral processing information to create a spatially-based (3D) predictive model for product management in mining operations (Lamberg, 2011).This case study investigates how to establish a geometallurgical model using the Malmberget iron ore deposit as a case study. A mineralogical approach (Lamberg 2011) was selected meaning that the focus is on mineralogy, and therefore parameters like modal mineralogy, mineral textures, mineral associations, mineral grain sizes and their relation to liberation characteristics are important. The main effort is to deliver a geological model which gives quantitative rather than descriptive information to be used in a process submodel.The ore characterisation (Papers I and II) gives new information on the chemical composition of minerals, mineralogical composition of both ore and host rocks, as well as the variation within the individual ore bodies. This sets a firm basis for the quantitative methods developed for routine analysis of modal mineralogy (Paper III) and mineral textures (Paper IV). Also, this increases the understanding regarding the primary origin and metamorphic evolution of the deposit, which is important since the origin of the apatite iron ore of the Kiruna type is still controversial.Based on the modal composition, preliminary geometallurgical (GEM) ore types were established for the Malmberget ore body. Each of these GEM-types describes quantitatively: the minerals present, their chemical composition, rules how to calculate the modal composition from routine chemical assays (element to mineral conversion, EMC rules) and a textural archetype in a library of archetypes. Using these GEM-types it is possible to calculate the modal mineralogy and the liberation distribution for every geological unit from the sample level to GEM-types to be further used in building a GEM block model of the ore.The applicability of the geological model was tested by developing a liberation based process model of simple one stage dry magnetic separation for the GEM-types. The model returns the metallurgical response, in terms of grade and recovery, of each of the developed GEM-types. The model was validated with another ore sample representing the same archetype from a different ore body and with a different grade. The model forecasted the recovery and concentrate grade within 2%-unit accuracy.This is the first published study where a full predictive geometallurgical model is entirely based on the mineralogy. The approach is a generic approach and valid not only for iron ores but also for other metallic mines. / Godkänd; 2013; 20130422 (luncec); Tillkännagivande disputation 2013-08-13 Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Cecilia Lund Ämne: Malmgeologi/Ore Geology Avhandling: Mineralogical, Chemical and Textural Characterisation of the Malmberget Iron Ore Deposit for a Geometallurgical Model Opponent: Professor emeritus Terje Malvik, Department of Geology and Mineral resources Engineering, NTNU, Trondheim, Norway Ordförande: Professor Pertti Lamberg, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Fredag den 6 september 2013, kl 10.00 Plats: F531, Luleå tekniska universitet

The Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit, situated in the Palaeoproterozoic (1.9–1.8 Ga) Bergslagen lithotectonic unit in the south-western part of the Fennoscandian Shield, is one of the major base and precious metal sulphide deposits in Sweden. Felsic volcanic rocks and limestone hosting the deposit, as well as their hydrothermally altered equivalents and the mineralization, were affected by heterogeneous ductile strain and metamorphism under low-pressure, lower amphibolite-facies conditions during the Svecokarelian orogeny (2.0–1.8 Ga). These processes reworked the mineral assemblages of the original hydrothermal system and the mineralization, and also reshaped the structural geometry of the deposit. A three-dimensional modelling approach has been used in order to evaluate geometric relationships between lithologies at the deposit. The polyphase character (D1 and D2) of the strong ductile deformation at Falun is apparent. The main rock-forming minerals in the altered silicate-rich rocks are quartz, biotite and anthophyllite with porphyroblasts of cordierite and garnet, as well as retrogressive chlorite. Major static grain growth occurred between D1 and D2, inferred to represent the peak of metamorphism, as well as after D2 with growth (or recrystallization) of anthophyllite. A major shear zone with chlorite, talc and disseminated sulphides bounds the pyritic Zn-Pb-Cu-rich massive sulphide mineralization to the north, the latter being surrounded elsewhere by disseminated to semi-massive Cu-Au mineralization. F2 sheath folding along axes plunging steeply to the south-south-east is suggested as a key deformation mechanism, accounting for the cone-shaped mineralized bodies, which pinch out at depth, and explaining the similar character of intensely altered rocks on all sides of the massive sulphide mineralization. Immobile-element lithogeochemistry suggests that they share a common volcanic precursor. These relationships are consistent with a model in which the pyritic massive sulphide mineralization is located in the core of a sheath fold structure, surrounded by the same altered stratigraphic footwall rocks with Cu-Au mineralization. The geological evolution in the metavolcanic inlier that hosts the Falun deposit, constrained by secondary ion mass spectrometry (SIMS) U–Pb (zircon) geochronology, involved emplacement of a felsic volcanic and sub-volcanic rock suite at 1894±3 Ma, followed by hydrothermal alteration and mineralization. Subsequent burial and intrusion of late- to post-mineralization dykes occurred between 1896±3 Ma and 1891±3 Ma, followed by further burial and emplacement of plutons with variable composition during the time span 1894±3 Ma to 1893±3 Ma. The age determinations for all these magmatic suites overlap within their uncertainties, indicating a rapid sequence of continuous burial and different magmatic pulses. A metamorphic event, herein dated at 1831±8 Ma and 1822±5 Ma (SIMS U–Pb monazite), falls in the age range of a younger Svecokarelian metamorphic episode (M2). U-Th-Pb isotope systematics in monazite was completely reset during this event. During hydrothermal alteration and mineralization, a hot, reducing and acidic fluid carrying metals and sulphur together flowed upward along syn-volcanic faults, leading to intense chloritization, sericitization and silicification of calc-alkaline volcanic rocks in the stratigraphic footwall to the deposit. This resulted in proximal siliceous associations including Fe-rich chlorite, and dominant Mg-rich chlorite and sericite in more peripheral parts. Cu-Au stockwork mineralization formed in the siliceous core of the hydrothermal system as result of fluid cooling. Neutralization of the metal-bearing fluids upon carbonate interaction stratigraphically higher in the sub-seafloor regime led to formation of Zn-Pb-Cu-rich massive sulphide mineralization, the space for which was created by a combination of carbonate dissolution, primary porosity in the overlying volcanic rocks and secondary porosity produced during syn-volcanic faulting. A hybrid model for mineralization is suggested by alteration styles, metal zoning and textures indicating replacement of carbonate rock or highly porous pumice breccia by pyritic massive sulphide. Aspects of a sub-seafloor volcanogenic massive sulphide (VMS) system and carbonate replacement are both present. Partly Zn-Pb-(Ag) mineralized skarns comprise a separate and subordinate type of mineralization, probably formed after burial of the hydrothermal system to the contact-metasomatic regime. Textures and microstructures in the massive sulphide mineralization indicate that the ductile deformation and metamorphism resulted in internal mechanical and chemical remobilization of sulphide minerals. Laser ablation inductively coupled mass spectrometry (LA-ICP-MS) analysis of the main sulphide minerals suggests, for example, that trace elements (including Au) were liberated from pyrite during metamorphism. A system of auriferous quartz veins, affected by D2 ductile strain, occurs in intensely altered and mineralized rocks on the eastern side of the deposit. It is suggested that they formed after the peak of metamorphism and prior to the completion of the D2 tectonic event, as a result of fluid-assisted remobilization of sulphides and Au in the disseminated to semi-massive Cu-Au mineralization and possibly also the massive sulphide mineralization. / Structural evolution, hydrothermal alteration and tectonic setting of the Falun base metal and gold deposit, Bergslagen region, Sweden

Tremendous physical and chemical exchanges occur along oceanic ridges between the lithosphere, the hydrosphere and the biosphere. During these exchanges important mobilisation of metals by hydrothermal fluid circulation takes place within the oceanic crust. Volcanogenic massive sulphide (VMS) deposits are hydrothermal ore deposits rich in Cu-Zn-Pb bearing sulphide minerals that form during submarine venting of these hydrothermal fluids near the seafloor. A proportion of the metals enriched in these deposits are mobilised from deeper crustal levels during high-temperature hydrothermal alteration. Gold-rich VMS deposits represent an important sub-set of VMS deposits that are enriched in Au and related elements such as As, Sb, Se and Te. The processes that form Au-rich VMS are still debated, due in part to our lack of understanding of the behaviour of these elements during formation and alteration of the oceanic crust. In this thesis we carry out a systematic investigation into the behaviour of Au, As, Sb, Se and Te during evolution of the oceanic crust. Three localities are studied: the Ocean Drilling Program (ODP) Hole 1256D in the Cocos plate, the Troodos ophiolite in Cyprus and the ODP Hole 786B in the Izu-Bonin forearc. The investigation has been carried out using cutting-edge analytical techniques including ultra-low detection limit analyses of Au and other metals in rock samples. The objectives of the thesis are 1) to quantify the mobilisation of metals including Au, related elements As, Sb, Se and Te and base metals during the alteration of the oceanic crust; 2) to determine the mineral reactions which promote this mobilisation; 3) to investigate the variability in metal mobility in different tectonic settings in the oceanic crust and 4) to investigate the extent to which the composition of  “source area” oceanic crust controls the composition of VMS deposits in different tectonic settings. The main outcomes of this study are fourfold. 1) The distribution of Au and related elements in primary crust varies considerably between different tectonic settings. Sulphide minerals play an important role in the behaviour of Au, Se and Cu during magmatic differentiation and hydrothermal alteration, but have a lesser influence on other metals. The oxidation state of the primary crust controls whether sulphide minerals are present, and thus is an important control on the budget and mobility of strongly chalcophile metals during hydrothermal alteration. 2) Large masses of Au and related elements are mobilised from the sheeted dyke complex in mid-oceanic ridge (MOR) and ophiolite settings. Significantly more metals are mobilised from the source areas than are trapped in the VMS deposits observed in these settings. Therefore, most of the metals mobilised from the source areas are lost, either during transport, venting, sedimentation or late fluid mobilisation. 3) Insufficient Au is mobilised from MOR settings at ODP Hole 1256D to form Au-rich VMS deposits. The quantity of Au mobilised from the Troodos ophiolite could potentially lead to Au-rich VMS formation but additional processes such as vapour separation by sub-seafloor boiling or magmatic volatile input would be required to increase the Au : base metal ratio. The lack of evidence for these processes in Troodos implies that Au-rich VMS deposits are not likely to be abundant in this area. 4) Isotopic and trace element evidence supports magmatic input in the hydrothermal system at ODP Hole 786B, implying that magmatic fluid input into hydrothermal systems leaves a specific signature which can be tracked. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.</p>

The Tjårrojåkka area is located about 50 km WSW of Kiruna, northern Sweden, and hosts one of the best examples of spatially related Fe-oxide Cu-Au occurrences (the Tjårrojåkka-Fe and Tjårrojåkka-Cu). The bedrock, depositional environment and tectonic evolution of the area were studied through petrological, geochemical and geophysical-petrophysical investigations. The bedrock is dominated by intermediate and basic extrusive and intrusive rocks. The intermediate andesites and basaltic andesites are cut by diabases which acted as feeder dykes for the overlying basalts. The intrusive rocks range from gabbro to quartz-monzodiorite in composition. The area is metamorphosed to epidote-amphibolite facies and has been affected by scapolite, K-feldspar, epidote and albite alteration that is more intense in the vicinity of deformation zones and mineralisations. Based on geochemistry the andesites and basaltic andesites are similar to the Svecofennian Porphyrite Group intermediate volcanic rocks, but have also features common with the intermediate volcaniclastic unit in the underlying Kiruna Greenstone Group. Chemically the basalts and diabases have the same signature, but cannot directly be correlated with any known basaltic unit. Some of the samples have characteristics comparable to the basalts of the Kiruna Greenstone Group. Whether the volcanic sequence at Tjårrojåkka represents the Porphyrite Group or is part of the greenstones could not be unequivocally determined without geochronological data. Three events of deformation have been distinguished in the Tjårrojåkka area; the first one involving NW-SE compression creating NE-SW-striking steep foliation corresponding with the strike of the Tjårrojåkka-Fe and Cu bodies, followed by the creation of an E-W deformation zone. Finally a second compressional event resulted in folding and the formation of a NNW-SSE striking and gently dipping structure possible related to thrusting from SW. The Tjårrojåkka apatite-magnetite ore (52.6 Mt of iron ore @ 51.5% Fe) is a blind ore consisting of a massive magnetite core surrounded by an ore- breccia containing low-grade Cu-mineralisation. Apatite, amphiboles and carbonate occur disseminated and as veins within the massive ore and in the wall rock. The Tjårrojåkka-Cu mineralisation is located 750 m from the Tjårrojåkka-Fe and contains 3.23 Mt ore @ 0.87% Cu. The main ore minerals are chalcopyrite and bornite occurring both disseminated and in veinlets. Minor pyrite, molybdenite and gold have also been observed. The host rock has been affected by strong albite, scapolite, amphibole and K-feldspar alteration. The alteration assemblages at Tjårrojåkka are highly variable with several of the alteration minerals occurring in several generations and settings, and with multiple reactivations of already existing veins and overlapping alteration stages indicating a complex, long history of fluid activity in the area. Similarity in alteration minerals and paragenesis in the iron and copper mineralisation is described in terms of whole rock geochemistry, mineral chemistry and paragenesis. This may partly be explained by the common host rock to the mineralisations, but indicates also similarities in fluid composition. Within the massive magnetite ore apatite, tremolite and carbonate veinlets fill fractures probably formed during cooling of the magnetite body. The wall rock has been affected by extensive pervasive albite and plagioclase alteration. Scapolite occurs locally as porphyroblasts and later veins. The albitised and scapolitised rocks are overprinted by pervasive K-feldspar alteration and veins of K-feldspar + Mg-hornblende ± titanite ± quartz ± magnetite ± sulphides along the foliation. Epidote is common in veins together with K-feldspar. Allanite occurs as an accessory mineral associated with epidote, otherwise REE-minerals are rare. Carbonate and zoelites were the last phases to form in vacancies. The area between the apatite-iron and copper bodies is strongly albite + magnetite altered. The footwall of the copper body is characterised by pervasive albite alteration spatially associated with magnetite and apatite veins cut by later carbonate veinlets. Scapolite (porphyroblasts and veins) is formed in an early stage in the hanging wall overprinted by pervasive K-feldspar alteration. Amphiboles (tschermakites, Mg-hornblende and actinolite) occur in several generations as porphyroblasts, in veins on its own, or together with K-feldspar ± titanite ± quartz ± carbonate ± chalcopyrite ± bornite. Epidote, REE- carbonate, zeolites and fluorite are the latest alteration phases in the copper mineralisation. Ba, Cl, S and F are enriched in the alteration minerals in the Tjårrojåkka occurrences. Barium-rich varieties of K-feldspar (max. 3.5% BaO) occur in the Cu-mineralised breccia surrounding the apatite-magneitie body indicating high concentrations of Ba in the hydrothermal fluids. Absence of sulphate in the fluids probably caused the formation of Ba-feldspars instead of barite. Scapolite shows a trend with more Cl-rich varieties around the magnetite body gradually getting more SO3 and CO2-rich in the Cu-mineralisation. The presence of accessory barite in the copper mineralisation also indicates that the SO3 content in the fluids were higher than in the iron ore. The biotites are rich in Ti while Cl and F contents are more moderate and do not show great variation in different parts of the systems. All amphiboles are Ca-rich ranging from tschermakites, Mg-hornblende to actinolite and tremolite. The apatites are F-dominate with higher Cl content in the apatite- iron ore than in the copper occurrence. Overall the alteration minerals related to the apaite-iron ore are more rich in Cl and Ba than the ones in the Cu-mineralisation that show higher contents of F, SO3 and CO2. / Godkänd; 2003; 20070215 (ysko)

No description available.