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  • 1551.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Holmström, Henning
    Geochemistry of the tailings - pond water interface in the flooded tailings pond at Stekenjokk, northern Sweden2000In: Vol. 5, no 2, p. 753-Article in journal (Other academic)
  • 1552.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Holmström, Henning
    Luleå tekniska universitet.
    Carlsson, Erik
    The geochemical dynamics of a pyrrhotite concentrate deposit, remediated by applying a till cover1999In: Vol. 4, no 1, p. 512-Article in journal (Other academic)
  • 1553.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Land, Magnus
    Andersson, P.S.
    Schönberg, H.
    Fractionation of Sm-Nd isotopes during weathering of till1998In: Mineralogical magazine, ISSN 0026-461X, E-ISSN 1471-8022, Vol. 62A, p. 1104-1105Article in journal (Other academic)
  • 1554.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Ponter, C.
    Geochemistry of till weathering in the Kalix river watershed, northern Sweden1990In: Chemical Weathering under Field Conditions: reports from a Nordic seminar, 27-28 September 1990, Wik, Uppsala / [ed] Kaj Rosen, Sveriges Lantbruksuniversitet, 1990, p. 1-18Conference paper (Refereed)
  • 1555.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Pontér, Christer
    Luleå tekniska universitet.
    Lead isotopes as tracers of environmental pollution from mining industries1991In: Abstracts: [2nd International Symposium on Environmental Geochemistry], including 3rd International Symposium on Environmental Geochemistry and Health and 9th European Meeting of The Society for Environmental Geochemistry and Health, 16-19 September 1991, Uppsala, Sweden / [ed] O Selinus, Uppsala: Sveriges Geologiska Undersökning , 1991Conference paper (Other academic)
  • 1556.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Pontér, Christer
    Lead isotopes as tracers of lead pollution from various sources: an example from northern Sweden1993In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 8, no Suppl. 2, p. 67-70Article in journal (Refereed)
    Abstract [en]

    The surface sediments in the central Bothnian Bay are contaminated with antropogenic Pb. Preindustrial sources of the Pb pollution are anthropogenic atmospheric Pb, where the main Pb source is combustion of gasoline, and ore from the Laisvall mine which is processed in the smelter Rönnskärsverken. Because the Pb isotope composition of these possible sources are known, an attempt was made to trace the origin of the antropogenic Pb by studying the Pb isotope composition of sediments. The results show unequivocally that Laisvall Pb is not the source of the pollution. The enrichment of Pb in surface sediments is caused by atmospheric deposition of Pb additives from gasoline. Lead emitted from Rönnskärsverken is deposited relatively close to the smelter, and has not reached central Bothnian Bay in traceable amounts.

  • 1557.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lager, Ingemar
    Luleå University of Technology.
    Loberg, Bengt E. H.
    Luleå University of Technology.
    Schöberg, Hans
    Stratigraphical position and Pb-Pb age of lower Proterozoic carbonate rocks from the Kalix greenstone belt, northern Sweden1992In: Geologiska föreningens i Stockholm förhandlingar, ISSN 0016-786X, Vol. 114, no 3, p. 317-322Article in journal (Refereed)
    Abstract [en]

    In the Kalix area, a more than 3600 m thick sequence of continental rift-associated, well-preserved metasedimentary and mafic metavolcanic rocks occurs in a Lower Proterozoic greenstone belt which has no connection to other areas of mafic volcanites. These supracrustals are probably resting on an Archaean basement, and overlain by at least 2000 m of schists of marine prigin. By analysing for Pb isotopes, an attempt was made to date intertidal dolomites with evenly laminated stromatolites and supratidal, pisolitic dolomite calcretes. The resultant age was 2.1 +/- 0.2 Ga. The large uncertainty is partly due to a narrow range of Pb isotopic ratios. Small-scale postdepositional redristribution of lead in the stromatolites is probable. The sample sites are stratigraphically situated just below a 400 m thick sequence of mafic metalavas, which can be correlated with c. 2.1 Ga old mafic metalavas in the Peräpohja Schist Belt in adjacent parts of northern Finland. Despite the large uncertainty of the age obtained, the lithostratigraphical correlations with the Peräpohja Belt suggest that 2.1 Ga is a good approximation of the depositional age of the rocks studied. Later transgression with subsequent deposition of marine sediments is older than the peak of Svecofennian igneous activity at c. 1.9 Ga.

  • 1558.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Land, Magnus
    Stockholms Universitet.
    Ingri, Johan
    Mobility and transport of Nd isotopes during weathering of till in a boreal forest2007In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 71, no 15S, p. A732-Article in journal (Other academic)
  • 1559.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Land, Magnus
    Mistra Council for Evidence-based Environmental Management (EviEM), The Royal Swedish Academy of Sciences.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Widerlund, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mobility and transport of Nd isotopes in the Vadose zone during weathering of granitic till in a boreal forest2014In: Aquatic geochemistry, ISSN 1380-6165, E-ISSN 1573-1421, Vol. 20, no 1, p. 1-17Article in journal (Refereed)
    Abstract [en]

    There is a broad correlation between the εNd values for rivers (including both the water and the particulate material it carries) and the age of the source terrain. This paper presents Nd isotope distribution data for soil, soil water, groundwater, and stream water samples gathered in a small catchment in northern Sweden. The results show that the release of Nd and Sm from boreal forests into streams and, eventually, into the oceans is more complicated than previously realized. The weathering of till causes changes in both the Nd isotopic composition and Sm/Nd ratios. Both the Sm/Nd ratio and εNd were higher in strongly weathered soils horizons than in less weathered till, since minerals with high Sm/Nd ratios were, on average, more resistant to weathering than those with low Sm/Nd ratios. In contrast to the situation for the main minerals and the major elements, the weathering of rare earth elements (REE) was not restricted to the E-horizon: the measured REE concentrations continued to increase with depth in the C-horizon. In addition, REE released by weathering in the upper parts of the soil profile were partly secondarily retained at deeper levels. Therefore, the dissolved Nd released by weathering in the upper soil horizons was trapped and did not enter the groundwater directly. Rather, the Nd in the groundwater largely originated from weathering within the groundwater zone. However, this was not the only source of Nd in the stream water. The Nd isotope composition and Sm/Nd ratio were determined by the mixing between of Nd and Sm in the groundwater and REE-carrying organic material washed out of the soil profile. The groundwater close to the stream reaches the upper soil horizons during high discharge events such as snowmelts, and organic matter carrying Nd and Sm is washed out of the soils and thus released into the stream. Therefore, the Nd exported from catchment is derived from both the weathering within the groundwater zone, and the organic matter washed out from the soil. If longer timescales with more advanced weathering stages in the groundwater zone are considered, it cannot be ruled out that there will be a shift towards more radiogenic values in the exported Nd. Recorded shifts in the Nd isotopic composition in the ocean may thus not only reflect changed source regions, but also the weathering history of the same source region

  • 1560. Öhlander, Björn
    et al.
    Land, Magnus
    Luleå tekniska universitet.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Widerlund, Anders
    Mobility of rare earth elements during weathering of till in northern Sweden1996In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 11, no 1-2, p. 93-99Article in journal (Refereed)
    Abstract [en]

    Continuous, volume-controlled sampling from the surface down to a depth of 130 cm was conducted at two stations on weathered till (typic haplocryods). All the samples were analysed for major and trace elements including the rare earth elements (REE). Eight thousand seven hundred years of weathering since the glacial ice left the area, has resulted in a strong depletion of REE in the E-horizon. This loss decreases as atomic number increases, so that 80-85% of the La and 54-60% of the Yb have been lost. Europium has been lost to a greater degree than have the neighbouring elements. Possible explanations for the release of REE are: weathering of common silicates such as hornblende and epidote (and plagioclase in the case of Eu); weathering of apatite; weathering of rare but REE-rich minerals such as allanite and monazite; and release of REE adsorbed on clay minerals. Further studies on various size fractions and minerals are needed to quantify the importance of the various possible mechanisms of REE release. The release of REE continues within and below the Bs1-horizon, but the results from one station show that light REE can be enriched in the Bs1-horizon. This secondary enrichment could be caused by adsorption on secondary oxy-hydroxides, on clay minerals or on organic material. However, the net result of the weathering is that all REE have been released to the groundwater.

  • 1561. Öhlander, Björn
    et al.
    Lindvall, Manfred
    Widerlund, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Holmström, Henning
    Carlsson, Erik
    Peinerud, Elsa K
    Correge, Olivier
    A system approach to mine waste remediation, the Kristineberg mine, northern Sweden2003In: Acid rock drainage: application and sustainability of technologies : sixth international conference ; 14 - 17 July 2003, Cairns, Queensland, Australia ; proceedings, Carlton, Victoria: The Australian Institute of Mining and Metallurgy , 2003, p. 81-92Conference paper (Refereed)
  • 1562.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ljungberg, J.
    Holmström, H.
    Luleå tekniska universitet.
    Desorption of metals retained secondarily after release by sulphide oxidation: the main mechanism for groundwater contamination in the tailings at the Laver mine, northern Sweden2001In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 123, no 3, p. 153-162Article in journal (Refereed)
    Abstract [en]

    Geochemical studies of pore water and groundwater in sulphide-bearing tailings have been performed at the Laver mine in northern Sweden. Pore water has been sampled from just above the groundwater table down to the peat and till underlying the tailings. Groundwater has been sampled weekly from April to November in pipes installed at various depths in the tailings. All samples were analysed for major and trace elements by using ICP-AES and ICP-MS. When the oxidation front in the tailings is moving downwards, metals released by weathering in this low-pH environment are to a large extent retained secondarily in the tailings below the oxidation front and do not reach the groundwater, except in areas where the oxidation front is situated close to the groundwater table. Vertical flow of precipitation water contaminated with metals released by sulphide oxidation is, thus, not the major explanation for groundwater contamination. Instead, contamination occurs when the advancing oxidation front pushes the secondary enrichments of metals ahead to meet the groundwater table and the metals are released to the groundwater. The release of metals is caused by desorption due to the low pH in this environment. Areas of the tailings deposit with shallow groundwater table are at present the main sources of metal release. There is a seasonal variation in the composition of groundwater, particularly shallow groundwater. This is caused by changing levels of the groundwater table. Rising groundwater table results in outflush of metals in areas where the groundwater reaches secondarily retained metals. A steady trend with rising groundwater table after snowmelt results in a larger proportion of contaminated water in shallow groundwater, which decreases during the autumn. Concentration peaks of Cu and other metals in shallow groundwater may be the result of small, rapid rises of the groundwater table due to strong precipitation, superimposed on the general seasonal trend.

  • 1563.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lu, Ming
    Alakangas, Lena
    Effect of liming a permanently stratifies pit lake, Rävlidmyran, northern Sweden2007In: Mining and the environment international conference: proceedings, Centre for Environmental Monitoring, Laurentian University , 2007Conference paper (Refereed)
    Abstract [en]

    Rävlidmyran pit lake situated in Northern Sweden had low pH, and a permanent stratification with anoxic water at depth. To improve the water quality, the pit lake was limed by using Ca(OH)2. Before liming, the lake was stratified with low pH (3.0 - 3.4) and high concentration of dissolved oxygen between 0 and 5 m depth, with a transition zone from 5 to 8 m depth, and a zone with pH 3.2 - 5.5 and very low dissolved oxygen from 8 m depth to the bottom. Metals such as Al, Cu and Pb had highest concentrations in the upper zone whereas the concentrations of most other elements including As, Ca, Cd, Fe, Mg, Mn, S and Zn increased with depth. The stratification remained also after the liming treatment. pH increased to about 8 in the whole water column although only one sixth of the Ca(OH)2 was rapidly dissolved, and the remaining part accumulated in the bottom sludge. Redox decreased, especially in the oxygen poor zone at depth. Concentrations of Fe, Mn, Zn and Mg decreased strongly in the upper oxic water, due to formation of oxyhydroxides. In the anoxic bottom water, the concentrations of these elements gradually increased towards pre-liming levels. Aluminium and Cu were almost completely depleted in the entire water column due to pH increase and precipitation of minerals such as gibbsite. The bottom sludge formed after the liming was dominated by Ca(OH)2, calcite and a group of Fe(II)-Fe(III) oxyhydroxides, so called green rust. Metals removed from the dissolved phase of the water column accumulated in the sludge. Although the bottom sludge will have a buffering effect for some time, the poor water mixing in the pit lake will rapidly result in acid water in the upper zones when liming ceases.Key Words: AMD, pit lake, liming, geochemistry, water column, bottom sludge

  • 1564.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Markkula, Heikki
    Luleå University of Technology.
    Alteration associated with the gold-bearing quartz veins at Middagsberget, northern Sweden1994In: Mineralium Deposita, ISSN 0026-4598, E-ISSN 1432-1866, Vol. 29, no 2, p. 120-127Article in journal (Refereed)
    Abstract [en]

    The mesothermal Au deposit at Middagsberget in northern Sweden is associated with irregular stock-works of quartz veins occurring in shear zones across a dioritic intrusion. Alteration in the shear zones is characterized by sericitization, chloritization, the presence of sulphides and several generations of veins and small-scale fractures. Small fractures which are filled with variable amounts of quartz, carbonate, sericite, chlorite, albite and sulphides, are particularly abundant in zones having a high Au content. In general, these fractures are younger than the major quartz veins and were apparently important for strong Au-enrichment. Au is associated with arsenopyrite and it occurs as droplets or interfillings in the arsenopyrite or at the crystal surface; together with pyrrhotite as inclusions in arsenopyrite; as free grains in silicates but close to arsenopyrite; or in very small fractures in carbonates. The Au-mineralization is associated with elevated contents of As, S, Sb and W and depletion of Cu, Zn, Ge and Bi. The entire altered areas are enriched in Au compared with the < 1 to 15 ppb found in the host intrusion. During alteration an initial increase in Na or K was accompanied by a weak enrichment of Au and associated elements together with a depletion of elements such as Ca and Mg. In Au-rich samples this alkali enrichment was overprinted by the carbonate-and sulphide-bearing fractures, which often led to an increased Ca-content. An clear zonation of alteration types has not been found. The host rock has been altered by several generations of fluids: the shear zones were repeatedly ruptured and new small-scale fractures were opened. The different fluids did not, therefore, flow through identical paths although they penetrated the same major zones. This resulted in a complex pattern of variously superimposed alterations.

  • 1565.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mellqvist, C.
    Skiöld, T.
    Swedish Museum of Natural History.
    Sm-Nd isotope evidence of a collisional event in the Precambrian of northern Sweden1999In: Precambrian Research, ISSN 0301-9268, E-ISSN 1872-7433, Vol. 93, no 1, p. 105-117Article in journal (Refereed)
    Abstract [en]

    The Sm-Nd isotope characteristics of c. 1.9 and c. 1.8 Ga granitoids occurring close to the edge of the Archaean craton in northern Sweden have been studied. Strongly negative εNd(t) values occur farther southwest in the potassic 1.8 Ga granitoids than in the calc-alkaline 1.9 Ga granitoids. Intrusions of the younger granitoids with distinctly negative εNd(t) values are surrounded by granitoids of the older group with positive values. Northeast of the 1.8 Ga granitoids discussed here, the c. 1.9 Ga calc-alkaline intrusions formed within the Archaean continent have the same Sm-Nd isotope characteristics as the 1.8 Ga granitoids to the southwest. Our interpretation is that a juvenile volcanic-arc terrane to the south collided with and was thrust onto the Archaean continent after the formation of the 1.9 Ga granitoids. The outcome was that these juvenile rock masses were obducted onto the reworked Archaean continent. The 1.8 Ga granitoids were formed by remobilisation of continental crust. Partial melting at 1.8 Ga resulted in the intrusion of granitoids carrying the Sm-Nd isotopic signature of the Archaean continent into juvenile rocks. It is probable that the collision discussed here was part of a major accretion and amalgamation to the Archaean craton after the formation of the calc-alkaline 1.9 Ga granitoids, but before the formation of the 1.8 Ga granitoids.

  • 1566.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Müller, Barbara
    Institute of Geotechnical Engineering, ETH Hönggerberg, Zürich.
    Axelsson, Mikael
    Varian Analytical Instruments, Solna.
    Alakangas, Lena
    An attempt to use LA-ICP-SMS to quantify enrichment of trace elements on pyrite surfaces in oxidizing mine tailings2007In: Journal of Geochemical Exploration, ISSN 0375-6742, E-ISSN 1879-1689, Vol. 92, no 1, p. 1-12Article in journal (Refereed)
    Abstract [en]

    Metals released from oxidation and weathering of sulphide minerals in mine tailings are to a high degree retained at deeper levels within the tailings themselves. To be able to predict what could happen in the future with these secondarily retained metals, it is important to understand the retention mechanisms. In this study an attempt to use laser ablation high-resolution ICP-MS (LA-ICP-SMS) to quantify enrichment of trace elements on pyrite surfaces in mine tailings was performed. Pyrite grains were collected from a profile through the pyrite-rich tailings at the Kristineberg mine in northern Sweden. At each spot hit by the laser, the surface layer was analyzed in the first shot, and a second shot on the same spot gave the chemical composition of the pyrite immediately below. The crater diameter for a laser shot was known, and by estimating the crater depth and total pyrite surface, the total enrichment on pyrite grains was calculated. Results are presented for As, Cd, Co, Cu, Ni and Zn. The results clearly show that there was an enrichment of As, Cd, Cu and Zn on the pyrite surfaces below the oxidation front in the tailings, but not of Co and Ni. Arsenic was also enriched on the pyrite grains that survived in the oxidized zone. Copper has been enriched on pyrite surfaces in unoxidized tailings in the largest amount, followed by Zn and As. However, only 1.4 to 3.1% of the Cd and Zn released by sulphide oxidation in the oxidized zone have been enriched on the pyrite surfaces in the unoxidized tailings, but for As and Cu corresponding figures are about 64 and 43%, respectively. There were many uncertainties in these calculations, and the results shall not be taken too literally but allowed the conclusion that enrichment on pyrite surfaces is an important process for retention of As and Cu below the oxidation front in pyrite rich tailings. Laser ablation is not a surface analysis technique, but more of a thin layer method, and gives no information on the type of processes resulting in enrichment on the pyrite surfaces. Although only pyrite grains that appeared to be fresh and without surface coatings were used in this study, the possibility that a thin layer of Fe-hydroxides occurred must be considered. Both adsorption to the pyrite directly or to Fe-oxyhydroxides may explain the enrichment of As, Cd, Cu and Zn on the pyrite surfaces, and, in the case of Cu, also the replacement of Fe(II) by Cu(II) in pyrite.

  • 1567.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nisca, Dan
    Tectonic control and genesis of Proterozoic molybdenite occurrences in northern Sweden1988In: Proceedings of the Seventh Quadrennial IAGOD Symposium / [ed] Ebbe Zachrisson, Taylor and Francis Group , 1988, p. 603-612Conference paper (Refereed)
  • 1568.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nisca, Dan
    Swedish Geological Co..
    Tectonic control of Precambrian molybdenite mineralization in Northern Sweden1985In: Economic geology and the bulletin of the Society of Economic Geologists, ISSN 0361-0128, E-ISSN 1554-0774, Vol. 80, no 2, p. 505-512Article in journal (Refereed)
    Abstract [en]

    The major molybdenite occurrences of N Sweden are mostly confined to the Proterozoic continental domain. The molybdenite occurrences are in aplites, pegmatites and metamorphosed volcanics, located in narrow supracrustal belts surrounding granites. The Mo deposits are associated with faults and dome structures (apical parts of cupolas), as recognized by geophysical methods

  • 1569.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nordblad, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lax, Kaj
    Geological Survey of Sweden.
    Ecke, Frauke
    Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Biogeochemical mapping of stream plants to trace acid sulphate soils: A comparison between water geochemistry and metal content in macrophytes2014In: Geochemistry: Exploration, Environment, Analysis, ISSN 1467-7873, E-ISSN 2041-4943, Vol. 14, no 1, p. 85-94Article in journal (Refereed)
    Abstract [en]

    The efficiency of biogeochemical mapping for identifying acid sulphate soils (AS soils) was studied by sampling and analysing water, transplanted aquatic moss (Fontinalis antipyretica) and leaves of the vascular plant Calamagrostis purpurea at two sites in a stream in northern Sweden with AS soils in its drainage area. One upstream sampling station (Mårtsmarken) was situated in an area dominated by till, and a downstream station (Persraningen) was situated in an area where AS soils are common. Metal contents in F. antipyretica and C. purpurea at these sites were compared to those in water (both unfiltered samples, and samples subjected to 0.22 μm membrane filtration and 1 kDa ultrafiltration to obtain data on metal speciation and its effects on uptake). Oxidation of sulphides with associated increases in acidity and release of metals were clearly reflected by differences in the water samples. At Persraningen the pH was lower than at Mårtsmarken, and the unfiltered concentrations of Al, Ca, Cd, Co, Cu, K, Mg, Mn, Ni, P, S, Sr, Y and Zn were higher. At the upstream station, Mårtsmarken, the suspended fraction was an important carrier of Fe and P, and the colloidal concentrations were higher than or similar to the dissolved concentrations for all determined elements except Na and K. At Persraningen the low pH resulted in changes of speciation, so that the dissolved concentrations were higher than the colloidal concentrations for most elements. For Al, As, Cr, Cu, Pb and Y, the dissolved and colloidal concentrations were similar. For Fe, the colloidal concentration was usually higher than the dissolved concentration, and suspended Fe was detected. Aluminium, Cr, Cu, Fe and Y concentrations were significantly higher in Fontinalis antipyretica at Persraningen than at Mårtsmarken. In addition, concentrations of Al and Fe in C. purpurea were significantly higher at Persraningen. Our results highlight the potential of biogeochemical mapping for predicting the occurrence of AS soils. A limitation is the strong pH dependence of the uptake of metals in the aquatic mosses resulting in that only a few of the elements typically occurring at high concentrations in waters draining AS soils are enriched in the macrophytes. A combination of maps showing both absolute concentrations and elemental ratios would be useful for this, including not only ratios of previously suggested utility (e.g. Y:Pb and Ni:Pb), but also others, such as Y:Ca, Al:Ca, Cu:Ca, Y:Mg, Al:Mg and Cu:Mg. © 2014 AAG/The Geological Society of London.

  • 1570.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Romer, Rolf L.
    Luleå University of Technology.
    Zircon ages of granites occuring along the Central Swedish Gravity Low1996In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 118, no 4, p. 217-225Article in journal (Refereed)
    Abstract [en]

    Two major types of late Svecofennian granitoids occur in south central Sweden. Large homogeneous massifs of coarse-grained granite with trace element characteristics typical of granites formed in tensional settings occur along the Central Swedish Gravity Low (CSGL). The other type comprises smaller intrusions of irregular, heterogeneous, locally derived granites (IHLD granites). We present U-Pb zircon ages are presented of one IHLD granite and of three varieties of the homogeneous intrusions. The result for the IHLD granite is 1779+-8 Ma. One of the samples of the homogeneous type yielded an age of 1769.7 +- 3.4 Ma. The remaining two samples have heterogeneous zircon populations. The emplacement age of these rocks is bracketed by the intercept ages of 1770 +- 6 and 1779 +- 23 Ma.The overlapping ages of granite groups of different types show that different types of granites were formed contemporaneously in the same region as a result of melt formation at various depths and from various sources.

  • 1571.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Schöberg, Hans
    Character and U-Pb zircon age of the Proterozoic Ale granite, northern Sweden1991In: Geologiska föreningens i Stockholm förhandlingar, ISSN 0016-786X, Vol. 113, no 2-3, p. 105-112Article in journal (Refereed)
    Abstract [en]

    The Ale granite west of Lule in northern Sweden forms an irregular, almost elliptical exposure covering an area of roughly 30 by 15 km in size. The central part of the intrusion consists of a homgeneous, quartz- and microcline-rich porphyritic granite, whereas its marginal parts are made up of a heterogeneous granite slightly less rich in quartz. Pegmatites and aplites are common in the surroundings. Zircons from two samples, one from the central part of the Ale granite and one from the border zone, were dated at 1802±3 (2σ) Ma and 1796±2 (2σ) Ma, respectively, by using the U-Pb method. An analysis of Sm-Nd istopes of these samples gave initital Nd values of -5.2 and -3.2, respectively, indicating a significant contribution of Archaean crustal material. Thirteen samples were analysed for major and trace elements. The isotopic and geochemical results suggest that the Ale granite was formed in a compressional environment 1.80 Ga ago, and that mature sediments were not an important source material.

  • 1572.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, T.
    Elming, Sten-åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Delineation and character of the Archaean-Proterozoic boundary in northern Sweden1993In: Vol. 5, no Suppl. 1, p. 320-321Article in journal (Other academic)
  • 1573.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, T.
    Elming, Sten-åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Claesson, S.
    Nisca, D.H.
    Luleå tekniska universitet.
    Delineation and character of the Archaean-Proterozoic boundary in northern Sweden1993In: Precambrian Research, ISSN 0301-9268, E-ISSN 1872-7433, Vol. 64, no 1-4, p. 67-84Article in journal (Refereed)
    Abstract [en]

    Before the deposition of a Proterozoic cover and the repeated Proterozoic reworking of the older rocks, the presently exposed Archaean areas in northern Sweden formed part of a coherent craton. In the present study, we have used Sm---Nd isotopic analyses of Proterozoic granitoids and metavolcanics to delineate the Archaean palaeoboundary. In a regional context, the transition from strongly negative εNd(t) values in the northeast to positive values in the southwest is distinct, and approximately defines the border of the old craton. The Archaean palaeoboundary extends in a WNW direction, and is subparallel to the longitudinal axis of the Skellefte sulphide ore district but it is situated ≈ 100 km farther to the north. The ≈ 1.9 Ga old granitoids on the two sides of the palaeoboundary were all formed in compressional environments, but those situated to the north have higher contents of LILE and LREE at similar contents of Si. This indicates that they were generated in an area with thicker crust and supports the location of the Archaean-Proterozoic palaeoboundary. There is no simple correlation between the Archaean palaeoboundary, as defined by the isotopic results, and any of the major fracture systems as interpreted from regional geophysical measurements. Reflection seismic work indicates that juvenile volcanic-arc terrains to the south have been thrust onto the Archaean craton. Possible thrust faults have been identified from aeromagnetic measurements. Rifting of the Archaean craton created a passive margin ≈ 2.0 Ga ago. Spreading shifted to convergence with subduction beneath the Archaean continent ≈ 1.9 Ga ago. Subsequently, the resulting juvenile volcanic arc collided with the old continent, and the Archaean palaeoboundary as existing today was formed by a collision characterized by overthrusting. The boundary then was disturbed by later deformation predominantly along NNE-trending fracture systems.

  • 1574.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, T.
    Laboratoriet för Isotopgeologi, Naturhistoriska Riksmuseet, Stockholm.
    Hamilton, P. J.
    IIsotope Geology Unit, Scottish Universities Research and Reactor Centre, East Kilbride, Glasgow.
    Claesson, L. Å.
    Swedish Geological Co..
    The western border of the Archaean province of the Baltic Shield: evidence from northern Sweden1987In: Contributions to Mineralogy and Petrology, ISSN 0010-7999, E-ISSN 1432-0967, Vol. 95, no 4, p. 437-450Article in journal (Refereed)
    Abstract [en]

    Restricted areas of acid to intermediate gneisses in northernmost Sweden are known to be Archaean and several other gneissic granodioritic to tonalitic massifs have been suggested to be of this age. To delimit the western border of the Archaean province of the Baltic Shield, and to characterize the Swedish Archaean, we have studied the 2.83 Ga old Soppero gneiss and 8 of the proposed Archaean massifs in northern Sweden by Sm-Nd isotopic analyses, U-Pb zircon dating (in two cases), and geochemistry. Of the Archaean gneisses proposed thus far, only those from the Soppero and Kukkola areas have Archaean ages (2.83 and 2.67 Ga, respectively). These gneisses have geochemical characteristics such as LREE-enrichment, low U-contents, and low K/Na-ratios, which are typical of Archaean TTG (tonalite-trondhjemite-granodiorite) rocks worldwide. The REE results indicate that the Soppero and the Kukkola gneisses were generated by partial melting of basic rocks, presumably amphibolites. According to the Sm-Nd isotopic data for the Soppero gneiss, this process occurred only a short time after initial segregation from the mantle (εNd values between +0.9 and +3.5). The Kukkola gneiss, however, has longer crustal residence time as indicated by negative εNd values (-1.0 and -2.5) at the U-Pb zircon age of 2.67 Ga. Evidence in support of an important event at that time is given by secondary overgrowth on zircon cores in the 2.83 Ga old Soppero gneiss. The Sm-Nd isotope results show that the Proterozoic granitoids in northern Sweden have a decreasing involvement of Archaean source material with increasing distance from the Archaean areas. Before the Proterozoic reworking, the rather small Archaean areas in northern Sweden presumably belonged to a large continuous Archaean craton. The western palaeoboundary of this craton in Sweden probably follows approximately a line extrapolated from the western limit of the Archaean of central Finland, passing west of Kukkola, and then continues to the Lofoten area in northern Norway.

  • 1575.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Contrasting 1.8 Ga granitoids in northern Sweden: the Edefors and Lina suites1993In: Abstracts of lectures and posters: 21:a Nordiska geologiska vintermötet 10-13 Januari 1994 Luleå / [ed] Jan-Anders Perdahl, Luleå: Högskolan i Luleå , 1993, p. 235-Conference paper (Other academic)
  • 1576.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Contrasting 1.8 Ga potassic granitoids in northern Sweden: the Edefors and Lina suites1996In: Jubilee issue: short papers and abstracts for the Jubilee meeting "Current problems, ideas and results in geology" : Stockholm 16th-18th October 1996 at the celebration of the 125th anniversary of the Geological society of Sweden / [ed] Björn Sundquist, Geologiska föreningen , 1996, p. 22-Conference paper (Other academic)
  • 1577.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Laboratory for Isotope Geology. Swedish Museum of Natural History, Stockholm.
    Diversity of 1.8 Ga potassic granitoids along the edge of the Archaean craton in northern Scandinavia: a result of melt formation at various depths and from various sources1994In: Lithos, ISSN 0024-4937, E-ISSN 1872-6143, Vol. 33, no 4, p. 265-283Article in journal (Refereed)
    Abstract [en]

    The edge of the Archaean craton in northern Scandinavia had been intensively reworked during the Svecofennian orogeny 1.93-1.86 Ga ago and was subsequently intruded by potassic granitoids of 1.79–1.80 Ga age. Despite similar or even identical ages and overlapping areas of occurrence, these rocks belong to two different groups, the Edefors and Lina granitoids, which have contrasting geochemistries and Sm---Nd isotopic characteristics. The Edefors granitoids range from syenites to granites, and are alkali-rich and distinctly metaluminous. They crystallized from dry magmas. This is indicated by the scarcity of pegmatites and aplites. The contacts to older rocks are often distinct, but gradual transitions to Lina-type granitoids are common. The Edefors granitoids have high contents of Zr but not of elements such as Y, REE, Ta and Nb, and have low Mg/Mg+Fe ratios. They also frequently have positive Eu anomalies, even in the quartz rich varieties. Initial εNd values range from −2.1 to +1.4, indicating that the Edefors granitoids were formed by the mixing of mantle-derived magmas and continental crustal materials. The amount of crustal component was probably less than 35% in most cases. The Lina granitoids are accompanied by abundant pegmatites and aplites. Ghost structures and remnants of country rock are common. True granites predominate, but also quartz monzonites occur. The content of HFS elements is low and the Mg/Mg+Fe ratios are higher than in the Edefors granitoids. Initial εNd values range from −9.3 to −3.7, reflecting a significant portion of Archaean Nd in the source materials. The Lina granitoids are largely the result of remobilisation of continental crust with a small input of juvenile material. However, the dominant source for these crustally derived granitoids are c. 1.9 Ga old granitoids. These carry a large proportion of Archaean Nd. The most probable environment of the formation of potassic migmatite granitoids, such as the Lina type, is a collision zone between two masses of felsic crust (e.g. arc-continent or continent-continent), but the details of such a collision in the Baltic Shield remain to evaluated. The formation of the Edefors granitoids could have been associated with an extensional zone developed due to delamination caused by separation of the down-dip oceanic lithosphere from the continental lithosphere.

  • 1578.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Diversity of approximately coeval 1.8 Ga granitoids in northern Sweden: a result of melt formation at various depths and from various sources1993In: Symposium on "The Svecofennian Domain": geological/geophysical aspects of the continental crust and annual meeting of IGCP-275. Abstract volume, 1993, p. 64-Conference paper (Other academic)
  • 1579.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Elming, Sten-åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    The Archaean-Proterozoic boundary in northern Sweden1992In: Abstracts Volume, IGCP 275 meeting Deep Geology of the Baltic Shield: Petrozavodsk September 15-17, 1992, 1992, p. 66-67Conference paper (Other academic)
  • 1580.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Nisca, Dan
    Delineation and origin of the Archaean-Proterozoic boundary in northern Sweden1990In: Abstracts: Second Symposium on the Baltic Shield with Workshop on Correlation with Laurentia, Lund, Sweden June 5-7, 1990, Lund: International Geological Correlation Programme , 1990, p. 69-Conference paper (Other academic)
  • 1581.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Thunberg, Jonas
    Luleå tekniska universitet.
    Land, Magnus
    Stockholm University.
    Höglund, Lars-Olof
    Kemakta Konsult AB.
    Han, Quishang
    Luleå tekniska universitet.
    Redistribution of trace metals in a mineralized spodosol due to weathering, Liikavaara, northern Sweden2003In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 18, no 6, p. 883-899Article in journal (Refereed)
    Abstract [en]

    The till east of the Liikavaara Östra ore deposit in northern Sweden is in some parts rich in Cu and other sulphide-associated metals. Groundwater flowing in this till has higher concentrations of Cu than groundwater in a reference area where the till has low concentrations of Cu and other metals. To understand the processes that release metals from the mineralized till at Liikavaara into the groundwater, the authors performed a detailed study of the <2 mm fraction of a till profile where the highest metal concentrations in the Liikavaara area occur. The geochemistry and mineralogy of the till were determined, and the soil water was sampled by tension lysimeters. The importance of local diffusion of Cu-bearing airborne dust from the adjacent Aitik mine tailings impoundment was quantified and solid speciation of metals in airborne material was performed by sequential extraction. The results from Liikavaara were compared to results from the reference area. Glacial ice picked up sulphide-rich material from the Liikavaara Östra Cu ore during its flow. This material was deposited in the till east of the ore body when the ice melted. The sulphides have been dissolved in the <2 mm fraction during 8.7 ka of weathering since the glacial ice retreated. After dissolution of the sulphides, Cu was redistributed and secondarily retained in association with Fe-oxyhydroxides and altered biotite. Other sulphide-associated elements such as Co, Ni and Zn show the same pattern in the till profile as Cu, though the concentrations are much lower. Uptake of Cu2+ in the biotite through ion exchange with K+ may be an important mechanism for Cu-enrichment in biotite at Liikavaara. The airborne dust is not the source of Cu in the till. Although the soil water at Liikavaara has higher concentrations of Cu and other metals than the soil water at the reference area, the Cu-concentration is too low for infiltrating soil water to explain the high Cu-concentrations observed in groundwater. The high metal concentrations in the till, of Cu in particular, cause the increased concentrations in the local groundwater. A fluctuating groundwater table washes out Cu and other metals from the till. It is possible that increased Cu concentration in the local groundwater is caused by dissolved organic complexes, or by colloids (<0.45 μm) rich in organic matter and/or Fe-oxyhydroxides

  • 1582.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Proterozoic mineralizations associated with granitoids in northern Sweden: Excursion guide no 71986In: 7th IAGOD symposium and Nordkalott project meeting / [ed] Ebbe Zachrisson, Sveriges Geologiska Undersökning , 1986Conference paper (Other academic)
  • 1583.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Widerlund, Anders
    Holmström, Henning
    Ingri, Johan
    MiMi – Field studies and characterisation: state-of-the-art-report1998Report (Other academic)
  • 1584.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Zuber, Josef
    Aspects of the formation of the 1.80-1.77 Ga old granitoids in south-central Sweden1990In: Vol. 112, no 2, p. 189-190Article in journal (Other academic)
  • 1585.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Zuber, Josef
    Luleå University of Technology.
    Genesis of the Fellingsbro-type granites: evidence from gravity measurements and geochemistry1988In: Geologiska föreningens i Stockholm förhandlingar, ISSN 0016-786X, Vol. 110, no 1, p. 39-54Article in journal (Refereed)
    Abstract [en]

    The Fellingsbro granite sensu stricto is a porphyritic coarse-grained rock characterized by red angular microcline megacrysts. Samples of the Fellingsbro and the similar Lisjö granite have been analysed chemically. Both intrusions belong to a belt of ca. 1.78 Ga old granites which coincides with a major negative gravity anomaly, the so called Central Swedish Gravity Low. We have carried out gravity measurements and obtained a fairly dense regional gravity network from the Fellingsbro area to Västerås. In addition, an approx. 60km long profile with gravity stations approx. 200m apart was measured across the Lisjö granite. The porphyritic Fellingsbro and Lisjö granites were generated in a tensional environment. They rose from a huge granite ridge through structurally controlled root zones, flowed out and formed mushroom-shaped intrusions. Even-grained grained granites occurring in the Fellingsbro and Lisjö areas were generated through a mixing between the original granitic magma and locally remobilized country rocks. The porphyritic granites are of the same age and have similar geochemical and geophysical properties as the Småland-Värmland granites. Both groups were probably generated in a tensional environment on the continental side of a major subduction-related calc-alkaline belt; remnants of which may be preserved in the Southwest Swedish Gneiss region. The Lisjö and Fellingsbro granites were generated more towards the interior of the pre-existing ca 1.9 Ga old continent.

  • 1586.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Zuber, Josef
    Luleå University of Technology.
    Geochemistry of the fellingsbro type granites, south central Sweden1988In: Geologie & Mijnbouw, ISSN 0016-7746, E-ISSN 1573-9708, Vol. 67, no 2-4, p. 213-225Article in journal (Refereed)
    Abstract [en]

    The Fellingsbro granite sensu stricto is a massive coarse-grained rock characterized by red, angular microcline megacrysts up to 7 cm long. The Lisjo granite is of the same type as the Fellingsbro granite but is situated 20 km to the NE. Gravity studies suggest that the Fellingsbro and Lisjo granites rose from a huge granite ridge through structuraly controlled root zones, forming mushroom-shaped intrusions. These porphyritic granites have the geochemical characteristics (eg high Y, Nb, Zr and HREE) of granites generated as "within-plate' or tensional rifting environments. The even-grained interior of the Lisjo granite and the contemporaneous Dingtuna and Pingstaberg granites, were generated by differentiation of granites with similar characteristics as the porphyritic Fellingsbro granite. Recently published U-Pb zircon datings have demonstrated that the Smaland-Varmland granite-porphyry Belt has approximately the same age as the granites in this study. We speculate that both groups were emplaced in a tensional environment on the continental side of a subduction related calc-alkaline belt, remnants of which may be preserved in the SW Swedish Gneiss Region.

  • 1587.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Applications of the DGT technique for measurements of anions and cations in natural waters2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Since the toxicity and mobility of trace metals are related to the metals' speciation, robust methods for trace metal speciation analysis are of great interest. During the last 15 years, hundreds of scientific articles have been published on the development and applications of the diffusive gradients in thin films (DGT) passive sampling technique.In this work the commercially available DGT containing ferrihydrite adsorbent, used for determination of phosphate and inorganic arsenic, was characterised with respect to anionic molybdate, antimonate, vanadate and tungstate determination. Tests were performed in the laboratory as well as in the field. Diffusion coefficients were determined for the anions using two different methods with good agreement. Simultaneous measurements of arsenate were conducted as quality control to facilitate comparison of the performance with previous work. The ferrihydrite-backed DGT was concluded useful for application over the pH-range 4 to 10 for vanadate and tungstate, and 4 to <8 for molybdate and antimonate. At pH values ≥8, deteriorating adsorption was observed.The combination of a restricted pore (RP) version of DGT and the normal open pore (OP) DGT was used for speciation of copper and nickel at three brackish water stations with different salinities in the Baltic Sea. Time series and depth profiles were taken, and complementary membrane- (<0.22 μm) and ultrafiltration (<1 kDa) was conducted. Comparing DGT and ultrafiltration measurements indicated that copper and nickel were complexed. Due to small differences in results between the OP and RP DGTs it was suggested that the complexes were smaller than the pore size of the RP gel (~1 nm) resulting in that both DGTs accumulating essentially the same fraction. Further, there seemed to be a trend in copper speciation indicating higher degree of strong complexation with increasing salinity. The low salinity stations are more affected by fluvial inputs which will likely affect the nature and composition of the organic ligands present. Assuming that copper forms more stable complexes with ligands of marine rather than terrestrial origin would be sufficient to explain the observed trend.

  • 1588.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Further characterisation and applications of the diffusive gradients in thin films technique: In situ measurements of anions and cations in environmental waters2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    As both the toxicity and the mobility of trace elements are related to chemical forms present, robust methods for element speciation analysis are of great interest. During the last 15 years, hundreds of scientific articles have been published on the development and applications of the diffusive gradients in thin films (DGT) passive sampling technique. The aim of this thesis was to explore new application areas as well as carry out further characterisation of DGT-adsorbents already on the market. The commercially available DGT containing ferrihydrite adsorbent, currently in use for the determination of phosphate and inorganic arsenic, was characterised with respect to anionic arsenate, molybdate, antimonate, vanadate and tungstate determination. Tests were performed in the laboratory as well as in the field. Diffusion coefficients were determined for the anions using two different methods with good agreement. Simultaneous measurements of arsenate were conducted as quality control to facilitate comparison of the performance with previous work. The ferrihydrite-backed DGT was concluded useful for application over the pH-range 4 to 10 for vanadate and tungstate, and 4 to <8 for molybdate and antimonate. At pH values ≥8, deteriorating adsorption was observed. Further investigations of the ferrihydrite-DGT device were done with respect to organic arsenic species. From previous research it is understood that the two most prevalent forms of organic arsenic in natural waters, monomethylarsinate (MMA) and dimethylarsonate (DMA), adsorb to ferrihydrite. It was concluded that MMA and under some conditions DMA are accumulated and might therefore be included in total arsenic measurements. A method for speciation of inorganic As, DMA and MMA was described. DGT sampling was applied at three stations, with different salinities, in the brackish Baltic Sea. Time series as well as vertical profiles were taken and complementary membrane- (<0.22 μm) and ultrafiltrations (<1 kDa) were conducted on discrete samples collected at 5 m depth. A combination of a restricted pore (RP) version of DGT and the normal open pore (OP) DGT, both loaded with Chelex cation exchanger, was used for speciation of copper and nickel. Due to minimal differences in results between the OP- and RP-DGTs it was suggested that the complexes were smaller than the pore size of the RP gel (~1 nm) resulting in both DGTs accumulating essentially the same fraction. Furthermore, there seemed to be a trend in copper speciation indicating a higher degree of strong complexation with increasing salinity. The low salinity stations are more impacted by fluvial inputs which will likely affect the nature and composition of the organic ligands present. Assuming that copper forms more stable complexes with ligands of marine rather than terrestrial origin would be sufficient to explain the observed trend. Additionally, uranium results from the same sampling tours were used to evaluate OP-DGT for in situ uranium measurements. Previous research has focused on laboratory studies for characterisation of a range of suitable uranium adsorbents, including Chelex. From the Baltic Sea study, a strong correlation between DGT-labile uranium and pH was revealed. The correlation could not be associated to organic complexation, since the ultrafiltration results implicated that uranium was truly dissolved. Instead it must be attributed to the formation of stable inorganic anionic uranyl-carbonate complexes, the stability of which increases with increasing numbers of carbonates and pH. Transplanted aquatic moss has commonly been used to monitor bioavailable trace metal contaminations in freshwater. Like the DGT technique the method has the advantage of generating time-weighted averaged concentrations. The DGT technique has in several previous studies been suggested to mimic biological uptake of trace metals. Four speciation/fractionation techniques – DGT, transplanted aquatic moss, ultrafiltration (1 kDa) and membrane filtration (0.22 μm) – were used in parallel for measurements of Al, Cd, Co, Cu, Fe, Mn, Ni and Zn in a contaminated freshwater stream in northern Sweden. Differences and similarities between the methods were investigated and how these depend on geochemical water quality. Strong correlations between DGT-results and the concentrations in the filtrate (<0.22 μm) and ultrafiltration permeate for Al, Cu, Cd, Co and Zn were detected and, generally, elevated trace metal concentrations were found in the transplanted moss, compared to moss from the non-polluted reference stream. However, no correlation between moss and DGT-labile concentrations could be discerned.

  • 1589. Österlund, Helene
    et al.
    Chlot, Sara
    Faarinen, Mikko
    ALS Laboratory Group, Luleå.
    Widerlund, Anders
    Rodushkin, Ilya
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    Simultaneous measurements of As, Mo, Sb, V and W using a ferrihydrite diffusive gradients in thin films (DGT) device2010In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 682, no 1-2, p. 59-65Article in journal (Refereed)
    Abstract [en]

    The ferrihydrite-backed DGT (diffusive gradients in thin films), recently developed for arsenic and phosphate measurements was, for the first time, characterized with respect to molybdate, antimonate, vanadate and tungstate determination. Arsenate was included in the characterization to allow comparison with literature data and thus provide quality control of the measurements. In addition to laboratory experiments, field measurements were carried out in a natural stream in northern Sweden affected by mine drainage. It was shown that ferrihydrite-DGT is suitable for simultaneous determination of labile arsenic, molybdate, antimonate, vanadate and tungstate over a wide pH range. Diffusion coefficients were estimated using two different methods; diffusion cell and direct uptake to DGT devices in synthetic solutions. Estimations of the coefficients using the direct uptake method were performed between pH 4 and 8. The results from the two methods agreed well irrespective of pH, except for molybdate and antimonate that showed decreased values at pH 8. Adsorption of the analytes to ferrihydrite gel discs was rapid at all pH values. However, there was a tendency toward lower adsorption affinity for antimonate compared to the other anions. 100% recovery of accumulated analytes was achieved through complete dissolution of the ferrihydrite adsorbent using 1.4 mol L-1 HNO3 with 0.1 mol L-1 HF. From field sampling it was concluded that the opportunities for accurate antimonate and molybdate determination decrease at pH ≥8.7. DGT labile concentrations were generally lower than dissolved concentrations. Relatively lower DGT concentrations, compared to dissolved (<0.45 μm), were observed under a period when ferric oxide precipitations were detected on the DGT protective filter.

  • 1590.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Faarinen, Mikko
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    Contribution of organic arsenic species to total arsenic measurements using ferrihydrite-backed diffusive gradients in thin films (DGT)2012In: Environmental Chemistry, ISSN 1448-2517, E-ISSN 1449-8979, Vol. 9, no 1, p. 55-62Article in journal (Refereed)
    Abstract [en]

    In previous publications discussing arsenic determination using ferrihydrite-backed diffusive gradients in thin films (DGT) devices, organic arsenic forms have been disregarded, even though it is known that the two most prevalent in natural waters, dimethylarsinate (DMA) and monomethylarsonate (MMA), may adsorb to ferrihydrite and thereby be included in the measurement. In this work the accumulation of DMA and MMA, as well as inorganic arsenite and arsenate, to ferrihydrite-backed DGT devices was investigated. It could be demonstrated that MMA, and under acidic conditions also DMA, adsorbed to the binding layer and might therefore contribute to the total mass of measured arsenic. Diffusion coefficients were measured for all four species to enable quantification of DGT-labile concentrations of organic and inorganic arsenic. Elution of the analytes from the ferrihydrite binding layer was performed using 1 mL of 1 M NaOH to facilitate arsenic speciation analysis using chromatographic separation. Average recovery rates were between 87 and 108%. This study shows that the contribution of DMA and MMA to the total accumulated mass must be taken into consideration when evaluating DGT data in future studies.

  • 1591.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Gelting, Johan
    Nordblad, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    ALS Scandinavia AB.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Copper and nickel in ultrafiltered brackish water: labile or non-labile?2012In: Marine Chemistry, ISSN 0304-4203, E-ISSN 1872-7581, Vol. 132-133, no 1, p. 34-43Article in journal (Refereed)
    Abstract [en]

    Copper and nickel were sampled at three stations in the Baltic Sea using diffusive gradients in thin films (DGT) passive samplers and ultrafiltration (< 1 kDa). Two versions of DGT devices were used, the normal open pore (OP) and a restricted pore (RP). The OP DGT and RP DGT concentrations closely followed each other both in depth profiles and time series. The lack of significant difference between OP and RP DGT suggests that the labile complexes were smaller than the pore size of the RP gel (approximately 1 nm). These data, together with OP DGT measurements at the same location in two different years, clearly demonstrate that the DGT method is robust and indicates reproducible results during routine field conditions.Between 50 and 80% of the ultrafiltered fractions for Ni and Cu could not be detected by the DGT method, using standard procedures. This suggests the presence of complexing ligands for Cu and Ni. Assuming 100% complexation of Ni to fulvic acid ligand gave DGT concentrations similar to ultrafiltered Ni concentrations. The equivalent calculation for Cu indicates that up to 75% of the ultrafiltered Cu fraction is non-labile. The non-labile Cu complexes are proposed to be produced at sea since the fraction increases with decreasing terrestrial influence.

  • 1592.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Rodushkin, Ilya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ylinenjärvi, Karin
    ALS Scandinavia AB.
    Baxter, Douglas
    Determination of total chlorine and bromine in solid wastes by sintering and inductively coupled plasma-sector field mass spectrometry2009In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 29, no 4, p. 1258-1264Article in journal (Refereed)
    Abstract [en]

    A sample preparation method based on sintering, followed by analysis by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) for the simultaneous determination of chloride and bromide in diverse and mixed solid wastes, has been evaluated. Samples and reference materials of known composition were mixed with a sintering agent containing Na2CO3 and ZnO and placed in an oven at 560 °C for 1 h. After cooling, the residues were leached with water prior to a cation-exchange assisted clean-up. Alternatively, a simple microwave-assisted digestion using only nitric acid was applied for comparison. Thereafter the samples were prepared for quantitative analysis by ICP-SFMS. The sintering method was evaluated by analysis of certified reference materials (CRMs) and by comparison with US EPA Method 5050 and ion chromatography with good agreement. Median RSDs for the sintering method were determined to 10% for both chlorine and bromine, and median recovery to 96% and 97%, respectively. Limits of detection (LODs) were 200 mg/kg for chlorine and 20 mg/kg for bromine. It was concluded that the sintering method is suitable for chlorine and bromine determination in several matrices like sewage sludge, plastics, and edible waste, as well as for waste mixtures. The sintering method was also applied for determination of other elements present in anionic forms, such as sulfur, arsenic, selenium and iodine.

29303132 1551 - 1592 of 1592
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