Siri Simonsen

• Bunzula, Violeta Lavínia; Müller, Axel; Erambert, Muriel; Schijndel, Valby van; Schulz, Bernhard & Götze, Jens [Show all 9 contributors for this article] (2025). The lithium mineralization potential of Pan-African pegmatites in Mozambique. Journal of Geochemical Exploration. ISSN 0375-6742. 279. doi: 10.1016/j.gexplo.2025.107882. Full text in Research Archive Show summary

  The Pan-African rare-element pegmatites of the Alto Ligonha Pegmatite District in northern Mozambique contain abundant Li-rich micas and primary Li aluminosilicates, such as spodumene. Given the rising global demand for Li in the manufacture of Li-ion batteries, these pegmatites are viewed as potential hard rock sources of Li. In this study, five pegmatites from the Alto Ligonha region were investigated to gain a better understanding of the fractionation processes of pegmatite melts that lead to Li enrichment and to assess the economic potential of the Li mineralization. Mica, quartz, and spodumene collected from various zones within these pegmatites were analyzed. Contents of Li, Rb, Cs, Ta, and Tl in mica and of Li and Al in quartz reveal a very strong internal fractionation of the pegmatite melt with progressing crystallization. Li2O contents in micas increase from 0.1 to 1.4 wt% in the wall zones, to 0.3–1.7 wt% in the intermediate zones, to 1.5–3.8 wt% in the core zones and up to 5.4 wt% in the core zone pockets. Using known mica/melt Li partition coefficients, the Li contents of the melt at the initial crystallization stage was calculated to be between 315 and 3910 ppm for the Li-rich pegmatites. The Li saturation of about 5000 ppm in respect to spodumene crystallization was exceeded for most pegmatites at the final core-zone crystallization. The theoretical calculations confirm field observations that spodumene occurs in pegmatite core zones only. The analyzed spodumene show low and variable bulk Li2O contents between 1.2 and 3.0 wt%. The low Li contents in spodumene are mainly the result of kaolinization due to tropical weathering. The final deposition of the released Li, however, could not be identified. Inferred resource calculations revealed that the investigated pegmatites contain low Li2O tonnages. However, spodumene as well as Li-rich mica might be mined selectively as a by-product of gemstone and columbite-tantalite mining.

• Molinero-García, Alberto; Müller, Axel; Martín-García, J.M.; Simonsen, Siri & Delgado, R. (2022). Provenance of quartz grains from soils over Quaternary terraces along the Guadalquivir River, Spain. Geoderma. ISSN 0016-7061. 414. doi: 10.1016/j.geoderma.2022.115769. Full text in Research Archive Show summary

  The characterisation of quartz grains’ chemical and mineralogical properties in sediments and sedimentary rocks is widely used in provenance studies. This paper analyses quartz grains from the coarse sand fraction in soils in Quaternary fluvial terraces (Guadalquivir River, southern Spain). The tentative soil ages are 0.3 ka (Haplic Fluvisol), 7 ka (Haplic Calcisol), 70 ka (Cutanic Luvisol), 300 ka (Lixic Calcisol) and 600 ka (Cutanic Luvisol). The quartz grains analyses shed light on the sedimentological history of these terraces. Scanning electron microscope cathodoluminescence (SEM-CL) characteristics, micro inclusion inventory established by Energy-dispersive X-ray spectroscopy (SEM-EDX) and trace element contents determined with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) of quartz grains permitted distinguishing six types of grains in the soils studied: metamorphic quartz (type 1), undeformed granitic quartz (type 2), strongly altered granitic quartz (type 3), recrystallised (deformed) granitic quartz (type 4), sandstone-derived quartz (type 5) and hydrothermal quartz grains (type 6). Metamorphic quartz grains (type 1) come from the Sierra Morena (Iberian Massif) and Sierra Nevada (Internal Betic Zone). Granitic quartz grains (types 2 to 4) come from Los Pedroches batholith and its associated plutons (Santa Elena and Linares). The sandstone-derived quartz type 5 comes from the numerous sandstone outcrops scattered in the central catchment area of the Guadalquivir River. Finally, hydrothermal quartz grains (type 6) originate from hydrothermal veins associated with subvolcanic rocks of the Los Pedroches batholith. Variations were noted in the proportions of quartz types in soils of different ages, attributed to spatial and temporal changes in the catchment area. The most remarkable change occurred between 500 and 240 ka ago when the catchment area extended into Sierra Nevadás metamorphic rocks, well reflected in type 1 content (lower in P2, P4, P5 and PM) and their characteristics (quartz with less healed fractures, less Al content, bigger mica microinclusions, smaller Al/Ti ratio) in the post-500–240 ka soils. Our study shows that the combined study of SEM-CL characteristics, micro inclusions (SEM-EDX), and trace element contents (LA-ICP-MS) of quartz grains is an efficient approach for characterising the provenance of quartz grains in the sand fraction of soils.

• Georgiev, Svetoslav V.; Stein, Holly J.; Yang, Gang; Hannah, Judith L.; Böttcher, Michael E. & Grice, Kliti [Show all 10 contributors for this article] (2020). Late Permian–Early Triassic environmental changes recorded by multi-isotope (Re-Os-N-Hg) data and trace metal distribution from the Hovea-3 section, Western Australia. Gondwana Research. ISSN 1342-937X. 88, p. 353–372. doi: 10.1016/j.gr.2020.07.007. Full text in Research Archive
• Finch, Adrian A.; McCreath, Jamie; Reekie, Callum DJ; Hutchison, William D; Ismaila, Abdulmalik & Armour-Brown, Ashlyn [Show all 8 contributors for this article] (2019). From Mantle to Motzfeldt: A genetic model for syenite-hosted Ta,Nb-mineralisation. Ore Geology Reviews. ISSN 0169-1368. 107, p. 402–416. doi: 10.1016/j.oregeorev.2019.02.032. Full text in Research Archive
• Johansson, Åke; Waight, Tod; Andersen, Tom & Simonsen, Siri Lene (2016). Geochemistry and petrogenesis of Mesoproterozoic A-type granitoids from the Danish island of Bornholm, southern Fennoscandia. Lithos. ISSN 0024-4937. 244, p. 94–108. doi: 10.1016/j.lithos.2015.11.031. Full text in Research Archive
• Müller, Benjamin; Haugen, Håvard Jostein; Simonsen, Siri Lene & Tiainen, Hanna (2016). Grain boundary corrosion of highly porous ceramic TiO<sub>2</sub> foams is reduced by annealing and quenching. Journal of the European Ceramic Society. ISSN 0955-2219. 36(1), p. 179–188. doi: 10.1016/j.jeurceramsoc.2015.09.014. Full text in Research Archive
• Pedersen, Unn; Andersen, Tom; Simonsen, Siri Lene & Erambert, Muriel (2016). Lead isotope analysis of pewter mounts from from the Viking ship burial at Gokstad: On the origin and use of raw materials. Archaeometry. ISSN 0003-813X. 58, p. 148–163. doi: 10.1111/arcm.12222. Full text in Research Archive
• Cornell, David H.; Schijndel, Valby van; Simonsen, Siri Lene & Frei, Dirk (2015). Geochronology of Mesoproterozoic hybrid intrusions in the Konkiep Terrane, Namibia, from passive to active continental margin in the Namaqua-Natal Wilson Cycle. Precambrian Research. ISSN 0301-9268. 265, p. 166–188. doi: 10.1016/j.precamres.2014.11.028. Full text in Research Archive
• Johansson, Åke; Andersen, Tom & Simonsen, Siri Lene (2015). Hafnium isotope characteristics of late Palaeoproterozoic magmatic rocks from Blekinge, southeast Sweden: possible correlation of small-scale Hf and Nd isotope variations in zircon and whole rocks. GFF. ISSN 1103-5897. 137(1), p. 74–82. doi: 10.1080/11035897.2014.992469. Full text in Research Archive
• Sjåstad, Knut Endre; Simonsen, Siri Lene & Andersen, Tom (2014). Lead isotope ratios for bullets, a descriptive approach for investigative purposes and a new method for sampling of bullet lead. Forensic Science International. ISSN 0379-0738. 244, p. 7–15. doi: 10.1016/j.forsciint.2014.07.008. Full text in Research Archive
• Schijndel, Valby van; Cornell, David H.; Frei, Dirk; Simonsen, Siri Lene & Whitehouse, Martin J. (2014). Crustal evolution of the Rehoboth Province from Archaean to Mesoproterozoic times: Insights from the Rehoboth Basement Inlier. Precambrian Research. ISSN 0301-9268. 240, p. 22–36. doi: 10.1016/j.precamres.2013.10.014. Full text in Research Archive
• Elburg, Marlina Augusta; Andersen, Tom; Bons, Paul D; Simonsen, Siri Lene & Weisheit, Anett (2013). New constraints on Phanerozoic magmatic and hydrothermal events in the Mt Painter Province, South Australia. Gondwana Research. ISSN 1342-937X. 24(2), p. 700–712. doi: 10.1016/j.gr.2012.12.017. Full text in Research Archive
• Sjåstad, Knut Endre; Andersen, Tom & Simonsen, Siri Lene (2013). Application of laser ablation inductively coupled plasma multicollector mass spectometry in determination of lead isotope ratios in common glass for forensic purposes. Spectrochimica Acta Part B - Atomic Spectroscopy. ISSN 0584-8547. 89, p. 84–92. doi: 10.1016/j.sab.2013.08.011. Full text in Research Archive
• McCreath, Jamie Allan; Finch, Adrian A.; Simonsen, Siri Lene; Donaldson, Colin Henry & Armour-Brown, Ashlyn (2012). Independent ages of magmatic and hydrothermal activity in alkaline igneous rocks: The Motzfeldt Centre, Gardar Province, South Greenland. Contributions to Mineralogy and Petrology. ISSN 0010-7999. 163(6), p. 967–982. doi: 10.1007/s00410-011-0709-1. Full text in Research Archive
• Sjåstad, Knut Endre; Andersen, Tom & Simonsen, Siri Lene (2012). Studies of SRM NIST glasses by laser ablation multicollector inductively coupled plasma source mass spectrometry (LA-ICP-MS). Journal of Analytical Atomic Spectrometry. ISSN 0267-9477. 27(6), p. 989–999. doi: 10.1039/c2ja10295a. Full text in Research Archive
• Augland, Lars Eivind; Andresen, Arild; Corfu, Fernando; Simonsen, Siri Lene & Andersen, Tom (2012). The Beiarn Nappe Complex: A record of Laurentian Early Silurian arc magmatism in the Uppermost Allochthon, Scandinavian Caledonides. Lithos. ISSN 0024-4937. 146, p. 233–252. doi: 10.1016/j.lithos.2012.05.016. Full text in Research Archive
• Elburg, Marlina Augusta; Andersen, Tom; Bons, Paul D; Weisheit, Anett; Simonsen, Siri Lene & Smet, Ingrid (2012). Metasomatism and metallogeny of A-type granites of the Mt Painter-Mt Babbage Inliers, South Australia. Lithos. ISSN 0024-4937. 151, p. 83–104. doi: 10.1016/j.lithos.2011.09.009. Full text in Research Archive
• Sjåstad, Knut Endre; Simonsen, Siri Lene & Andersen, Tom (2011). Use of lead isotopic ratios to discriminate glass samples in forensic science. Journal of Analytical Atomic Spectrometry. ISSN 0267-9477. 26(2), p. 325–333. doi: 10.1039/c0ja00054j. Full text in Research Archive
• Sanna, Laura; Saez, Francisco; Simonsen, Siri; Constantin, Silviu; Calaforra, Jose-Maria & Forti, Paolo [Show all 7 contributors for this article] (2010). Uranium-series dating of gypsum speleothems: methodology and examples. International Journal of Speleology. ISSN 0392-6672. 39(1), p. 35–46. Full text in Research Archive Show summary

  Saez, Francisco: c/Actor Paco Rabal, 1-1E 30820 Alcantarilla, Murcia, Spain-/tøf

• Andersen, Tom; Andersson, UB; Graham, Stuart; Aberg, G & Simonsen, Siri Lene (2009). Granitic magmatism by melting of juvenile continental crust: new constraints on the source of Palaeoproterozoic granitoids in Fennoscandia from Hf isotopes in zircon. Journal of the Geological Society. ISSN 0016-7649. 166, p. 233–247. Full text in Research Archive
• Frezzotti, Maria-Luce; Andersen, Tom; Neumann, Else Ragnhild & Simonsen, Siri Lene (2002). Carbonatit melt-CO2 fluid inclusions in mantle xenoliths from Tenerife, Canary Islands: a story of trapping, immiscibility and fluid-rock interaction in the upper mantle. Lithos. ISSN 0024-4937. 64, p. 77–96. Full text in Research Archive Show summary

  Three types of fluid inclusions have been identified in olivine porphyroclasts in spinel harzburgite and lherzolite xenoliths from Tenerife: pure CO2 (Type A); carbonate-rich CO2-SO2 mixtures (Type B); and polyphase inclusions dominated by silicate glass fluid sp silicate sulfide carbonate (Type C). Type A inclusions commonly exhibit a "coating" (a few m thick) consisting of an aggregate of a platy, hydrous Si-Mg-Fe phase, most likely talc, together with very small amounts of halite, dolomite and other phases. Larger crystals (e.g. (Na,K)Cl, dolomite, spinel, sulfide and phlogopite) may be found on either side of the "coating", towards the wall of the host mineral or towards the inclusion center. These different fluids formed through immiscible separations and fluid - wall-rock reactions from a common, volatile-rich, siliceous, alkaline carbonatite melt infiltrating the upper mantle beneath Tenerife. First the original siliceous carbonatite melt separated into a mixed CO2-H2O-NaCl fluid and a silicate/silicocarbonatite melt (preserved in Type A inclusions). Reaction of the carbonaceous silicate melt with wall-rock minerals gave rise to large poikilitic orthopyroxene and clinopyroxene grains, and smaller neoblasts. During the metasomatic processes consumption of the silicate part of the melt produced carbonate-enriched Type B CO2-SO2 fluids which were trapped in exsolved orthopyroxene porphyroclasts. At later stages, the interstitial silicate/silicocarbonatite fluid was trapped as Type C inclusions. At some temperature above 650 C the mixed CO2-H2O-NaCl fluid inside Type A inclusions separated into CO2-rich fluid and H2O-NaCl brine. At T<650 C the residual silicate melt reacted with the host olivine, forming a reaction rim or "coating" along the inclusions walls consisting of talc (or possibly serpentine) together with minute crystals of NaCl, KCl, carbonates and sulfides, leaving a residual CO2 fluid. The homogenization of +2 to +25 C temperatures obtained from Type A CO2 inclusions reflect the densities of the residual CO2 after reactions with the olivine host, and are unrelated to the initial fluid density or the external pressure at the time of trapping. The latter are restricted by estimated crystallization temperatures of 1000-1200 C, and the spinel lherzolite phase assemblage of the xenolith, that is 0.7-1.7 GPa.

• Neumann, Else Ragnhild; Sørensen, Vivian; Simonsen, Siri Lene & Johnsen, Kari (2000). Gabbroic xenoliths from La Palma, Tenerife and Lanzarote, Canary Islands: Evidence for reactions between Canary Islands melts and old oceanic crust. Journal of Volcanology and Geothermal Research. ISSN 0377-0273. 103, p. 313–342. Full text in Research Archive
• Simonsen, Siri Lene; Neumann, Else Ragnhild & Seim, Kristin (2000). Sr-Nd-Pb isotope and trace element geochemistry of basaltic lavas in Tenerife: evidence for regional variations. Journal of Volcanology and Geothermal Research. ISSN 0377-0273. 103, p. 299–312. Full text in Research Archive
• Neumann, Else Ragnhild; Wulff-Pedersen, Erik; Simonsen, Siri Lene; Pearson, Norman J.; Mitjavila, J. & Marti, J. (1999). Evidence for fractional crystallization of periodically refilled magma chambers in Tenerife, Canary Islands. Journal of Petrology. ISSN 0022-3530. 40, p. 1089–1123. Full text in Research Archive

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• Zimmerman, Aaron; Reynard, Bruno; Kreiner, Douglas C; Stein, Holly; Hannah, Judith & Kimball, Justin [Show all 8 contributors for this article] (2025). Re-Os Lens on the Enigmatic Pogo Au District, Tintina Au Province, Alaska. Goldschmidt Conference Abstracts. 2025. Full text in Research Archive Show summary

  Models for low-sulfide, quartz vein hosted Au deposits are many and highly variable, whether the discussion be on relationship to magma composition, fluid source, or Au source(s) and transport. The well-endowed Tintina Au Province, spanning interior Alaska and the Yukon is exemplary, containing numerous diverse gold deposits that prove difficult to relate to one another. Pogo lacks obvious temporally related intrusion(s) for a potential Au source, even as the metamorphosed (pre-120 Ma) Devonian-Mississippian basement is filled with Cretaceous intrusions emplaced continuously from ~115-90 Ma across the region. Pogo is defined by gently northwest-dipping sheeted quartz-dominant lodes exhibiting variable pre- and post-mineralization fault-related deformation. Gold-bearing quartz lodes exhibit overprinting relations including quartz textures that present as multiple ghost breccias with multiple annealing events. Magmatism in the immediate region is restricted to ~114-112 Ma altered and mineralized peraluminous granites, the ~107 Ma Goodpaster batholith >5 km away, and ~98-93 Ma monzodiorite plutons cutting mineralization. Re-Os geochronology on Au-associated sulfides (pyrrhotite and arsenopyrite) in some Pogo deposits suggest pyrrhotite may be slightly older (~112-110 Ma). The majority of arsenopyrite (interestingly, two varieties, one with and the other without common Os) provides Re-Os ages of ~106-105 Ma. Here we address an unexpected age of ~142 Ma, determined for a highly unusual vein type at Pogo. Non-planar, hairline to 3-mm auriferous sulfide veinlets with tight squiggle-like morphologies, prominently crisscross an undefined, but seemingly early quartz generation. The mineralogy of these veins is pyrrhotite and arsenopyrite, with disseminated Au, and Bi2Te3. Both SEM and CT imaging support emplacement of the auriferous sulfide veinlets during a catastrophic event that appears to have produced nearly simultaneous sulfide-Au-Bi-Te and local quartz melt. Rounded sulfide-Au- Bi2Te3 melt-like blobs are suspended in quartz together with mostly rounded quartz grains containing the same sulfide-Au-Bi-Te mineralogy as the vein. Melting, freezing and brecciation may define a nearly instantaneous geologic time span. Significantly, initial 187Os/188Os ratios for key isochrons are chondritic. We are presently investigating quartz and Pogo’s non-magnetic pyrrhotite using Raman spectroscopy, in the context of a possible impact origin for early Pogo mineralization. Special thanks to Northern Star for samples and support.

• Augland, Lars Eivind; Andresen, Arild; Corfu, Fernando; Simonsen, Siri Lene & Andersen, Tom (2012). The Beiarn Nappe Complex: a record of Laurentian Early Silurian arc magmatism in the Uppermost Allochthonon, Scandinavian Caledonides. Full text in Research Archive
• Andersen, Tom; Simonsen, Siri Lene & Rämö, O.T. (2008). Laser-ablation multicollector inductively coupled mass spectrometry: Development, and application to Mesoproterozoic A-type granites in Antarctica. Full text in Research Archive
• Damås, Jan Kristian; Gullestad, Lars; Ueland, Thor; Solum, Nils Olav; Simonsen, Siri Lene & Frøland, Stig Sophus [Show all 7 contributors for this article] (1999). Elevated circulating levels of CXC-chemokines, a new group of cytokines involved in the pathogenesis of congestive heart failure. Full text in Research Archive
• Simonsen, Siri Lene & Neumann, Else Ragnhild (1999). Change in apatite chemistry during the evolution of the Diego Hernandez Formation. Full text in Research Archive
• Neumann, Else Ragnhild; Sørensen, Vivian; Simonsen, Siri Lene & Johnsen, Kari (1999). Gabbroic Xenoliths from La Palma, Tenerife and Lanzarote, Canary Islands: Evidence for Reactions between Canary Islands Melts and Old Oceanic Crust. Full text in Research Archive
• Neumann, Else Ragnhild; Simonsen, Siri Lene; Wulff-Pedersen, Erik & Seim, Kristin (1998). Source regions of Tenerife magmatism. Full text in Research Archive
• Neumann, Else Ragnhild; Wulff-Pedersen, Erik; Simonsen, Siri Lene & Pearson, Norman J. (1998). Magma chamber processes and eruptive mechanisms. Full text in Research Archive
• Simonsen, Siri Lene; Neumann, Else Ragnhild; Wulff-Pedersen, Erik & Seim, Kristin (1998). Decoupling between trace element ratios and radiogenic isotope data from Tenerife, Canary Islands. Full text in Research Archive
• Simonsen, Siri Lene; Neumann, Else Ragnhild; Wulff-Pedersen, Erik & Seim, Kristin (1998). Decoupling between trace element ratios and radiogenic isotope data from Tenerife, Canary Islands. Full text in Research Archive
• Simonsen, Siri Lene (1997). Mantel-Crust mixing modelling in the Gjeving complex, South Norway. Full text in Research Archive
• Simonsen, Siri Lene (1997). Radiogenic isotope systematics of charnockite and retrograded augen gneiss in the Gjeving complex, South Norway. Universitetet i Oslo. Full text in Research Archive

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