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- Ingri, Johan, et al.
(författare)
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Hydrogeochemistry of sulfur isotopes in the Kalix River catchment, northern Sweden
- 1997
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Ingår i: Applied Geochemistry. - 0883-2927 .- 1872-9134. ; 12:4, s. 483-496
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Tidskriftsartikel (refereegranskat)abstract
- The 34S-to-32S ratio in dissolved SO4 has been studied in the Kalix River, Northern Sweden, and its catchment. Weekly sampling over 17 months revealed temporal variations from +5.3‰ up to +7.4‰ in the δ34S values in the river. Snow and rain samples showed lower δ34S values (average +5.6‰ and +5.0‰, respectively). The atmosphere is the major source for S in surface waters in the catchment, and the heavier δ34S values in the river are a result of SO4 reduction within the catchment. Most of the temporal variations in the δ34S value in the river are caused by a mixing of water from the mountain areas (relatively light δ34S) and the woodland. The δ34S value is relatively heavy in the woodland tributaries because of bacterial SO4 reduction in peatland areas influenced by groundwater. The highest δ34S values were measured during the spring flood, in June and in November. These heavy δ34S values are related to different types of water with diverse origins. The heavy δ34S values coinciding with the early spring flood originate from peatland areas in the woodland. Relatively heavy δ34S values (up to +14.4‰) were registered in mire water. Smaller variations of the δ34S value during summer and early autumn most likely were caused by the input of ground-mire water during heavy rains. A correlation between increased TOC concentrations and increased δ34S values was observed. The heavy δ34S values in June and November probably originate from SO4 reduction in bottom water and sediments in lakes within the catchment. Bottom water, enriched in 34S---SO4, was transported in the river during the spring and autumn overturn.
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| 2. |
- Billstrom, K., et al.
(författare)
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Geochronological, stable isotopes and fluid inclusion constraints for a premetamorphic development of the intrusive-hosted Bjorkdal Au deposit, northern Sweden
- 2009
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Ingår i: International journal of earth sciences. - : Springer Science and Business Media LLC. - 1437-3254 .- 1437-3262. ; 98:5, s. 1027-1052
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Tidskriftsartikel (refereegranskat)abstract
- The Bjorkdal gold deposit, bound to a quartz vein system which is mainly hosted by a quartz-monzodioritic intrusion, is situated at the easternmost part of the 1.9 Ga Skellefte base metal district in the Fennoscandian shield. Three fluid stages may be distinguished, referred to as a ""barren"" stage, a main gold stage, and a remobilization stage, respectively. From oxygen and hydrogen isotope evidence, it is argued that fluids of different origins (magmatic and surface waters) penetrated the ore zone at the inferred stages, but regional metamorphic fluids appear essentially only to have redistributed elements. Early quartz veining took place during a pre-metamorphic stage at ca. 1.88 Ga, as evidenced by unradiogenic galena data and an Sm-Nd scheelite errorchron of 1,915 +/- A 32 Ma (MSWD = 0.25). Temporarily, the main ore-forming stage was closely related to the first barren stage and took place during a major uplift event close to 1.88 Ga. Although other source rocks cannot be totally ruled out, available isotope data (O, S, Sr and Pb) are seemingly consistent with the view that these elements, and by inference other ore elements, were derived from the host intrusion.
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| 7. |
- Kilpi, F, et al.
(författare)
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The Authors Respond
- 2018
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Ingår i: Epidemiology (Cambridge, Mass.). - 1531-5487. ; 29:4, s. E37-E37
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 8. |
- Mörth, Carl-Magnus, et al.
(författare)
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Sources of stream water sulfate during the spring snowmelt in boreal streams: evidence from stable 34S isotope measurements
- 2008
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Ingår i: Journal of Geophysical Research – Biogeosciences. ; 113, s. G01005-
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Tidskriftsartikel (refereegranskat)abstract
- Episodic hydrological events, such as snowmelt during spring, have a marked effect on stream water chemistry. Here we investigated how spring snowmelt affected δ 34S values of sulfate in six streams situated in northern Sweden. Four streams had high δ 34SSO4 values during base flow with values ranging from +11.9 to +8.6‰. During snowmelt the δ 34SSO4 decreased to around +6‰. In one of the streams and in the forested upper reaches of a second stream, δ 34SSO4 values were close to +5‰ during base flow and decreased to about +3.8‰ during the spring snowmelt. One stream, which drained cultivated postglacial sediments dominated by acid sulfuric soils, was differentiated from the other streams by low δ 34SSO4 values (−5.0‰ to −0.5‰). We could identify two stream water SO4 sources: sedimentary sulfides and anthropogenic S. Bacterial dissimilatory sulfate reduction was identified as an important process affecting stream water δ 34SSO4 values and suggests that in this boreal landscape, peatlands and possibly riparian zones have a large influence on the biogeochemistry of SO4 2− during base flow conditions. Our results suggest that during the spring snowmelt, snow S and desorbing SO4 of mainly anthropogenic origin are the two major S sources in four of the investigated streams. Two streams in forested areas also indicate that reoxidation of reduced S may be released during the spring flood. The stream in the cultivated area was found to be strongly influenced by the acid sulfuric soils independent of stream flow conditions.
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