Nina Simon

• Räss, Ludovic; Yarushina, Viktoriya M.; Simon, Nina Simone C & Podladchikov, Y.Y. (2015). High permeability pathways triggered by subsurface storage operations, Proceedings second EAGE workshop on geomechanics and energy : the ground as energy source and storage. European Association of Geoscientists and Engineers (EAGE). ISSN 9789462821613. doi: 10.3997/2214-4609.201414305. Full text in Research Archive
• Yarushina, Viktoriya M.; Räss, L.; Simon, Nina Simone C & Podladchikov, Y.Y. (2015). Shear-induced dilation and its implications for chimney flow in porous rocks, Proceedings second EAGE workshop on geomechanics and energy : the ground as energy source and storage. European Association of Geoscientists and Engineers (EAGE). ISSN 9789462821613. doi: 10.3997/2214-4609.201414304. Full text in Research Archive
• Gac, Sebastien; Huismans, Ritske; Simon, Nina Simone C; Faleide, Jan Inge & Podladchikov, Yuri Y. (2014). Effects of lithosphere buckling on subsidence and hydrocarbon maturation: A case-study from the ultra-deep East Barents Sea basin. Earth and Planetary Science Letters. ISSN 0012-821X. 407, p. 123–133. doi: 10.1016/j.epsl.2014.09.029. Full text in Research Archive
• Räss, Ludovic; Yarushina, Viktoriya M.; Simon, Nina Simone C & Podladchikov, Yuri Y. (2014). Chimneys, channels, pathway flow or water conducting features - an explanation from numerical modelling and implications for CO2 storage. Energy Procedia. 63, p. 3761–3774. doi: 10.1016/j.egypro.2014.11.405. Full text in Research Archive Show summary

  Large amounts of CO2 have to be captured, transported, injected and safely stored in the subsurface in order to counteract increasing atmospheric CO2 concentrations due to steadily high consumption of energy from fossil fuels. The injection of gigatons of carbon dioxide poses challenges for pressure management and the mechanical integrity of the storage complex. Optimizing the injection strategy, controlling deformation, preventing leakage and assuring safe long term containment requires reliable and predictive hydromechanical modelling. Based on a newly derived thermodynamically consistent set of equations we have developed fully coupled codes in one, two and three dimensions. In accordance with field observations and laboratory measurements, stress dependent poro- viscoelastoplastic deformation is taken into account. Our simulations predict the spontaneous formation of self- localizing high-porosity channels (or pathway flow) under conditions applicable to CO2 storage in reservoirs. These channels form due to mechanical instabilities that occur as a natural outcome of buoyancy driven flow in viscoplastically deforming rocks. Our results indicate that viscous deformation may explain the formation of chimneys such as those observed at the Sleipner pilot, and that non-linear effects have a major impact on the velocity and distribution of the fluid as well as on stress and deformation of the rock matrix. Thus, complex rheology and non-linear coupling between porosity, permeability, pressures and stresses should be included in state of the art reservoir simulation software in order to determine safe injection and storage conditions and correctly model observations and monitoring results.

• Semprich, Julia & Simon, Nina Simone C (2014). Inhibited eclogitization and consequences for geophysical rock properties and delamination models: Constraints from cratonic lower crustal xenoliths. Gondwana Research. ISSN 1342-937X. 25(2), p. 668–684. doi: 10.1016/j.gr.2012.08.018. Full text in Research Archive
• Gac, Sebastien; Huismans, Ritske; Simon, Nina Simone C; Podladchikov, Yuri Y. & Faleide, Jan Inge (2013). Formation of intracratonic basins by lithospheric shortening and phase changes: a case study from the ultra-deep East Barents Sea basin. Terra Nova. ISSN 0954-4879. 25(6), p. 459–464. doi: 10.1111/ter.12057. Full text in Research Archive
• Beuchert, Marcus; Podladchikov, Yuri P.; Simon, Nina Simone C & Rüpke, Lars Heimuth (2010). Modeling of craton stability using a viscoelastic rheology. Journal of Geophysical Research (JGR): Solid Earth. ISSN 2169-9313. 115. doi: 10.1029/2009JB006482. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Podladchikov, Yuri P. (2010). Density variations in the thickened crust as a function of pressure, temperature, and composition. International journal of earth sciences. ISSN 1437-3254. 99(7), p. 1487–1510. doi: 10.1007/s00531-010-0557-7. Full text in Research Archive
• Neumann, Else Ragnhild & Simon, Nina Simone C (2009). Ultra-refractory mantle xenoliths from ocean islands: how do they compare to peridotites retrieved from oceanic sub-arc mantle? Lithos. ISSN 0024-4937. 107(1-2), p. 1–16. doi: 10.1016/j.lithos.2008.06.003. Full text in Research Archive Show summary

  Ultra-refractory harzburgitic mantle is abundantly sampled as xenoliths in ocean island magmas. Its occurrence has potentially important implications for both geochemistry and geodynamics, and we therefore need to understand how these unusually refractory compositions form. In this contribution, we compare ultra-refractory spinel harzburgite xenoliths from ocean islands with peridotites collected along active arcs, based on available major element data on rocks and their minerals. The compositions of arc peridotites vary from ultra-refractory to fertile and estimated equilibration temperatures range from about 800 to >1300 ºC. These variations are not directly related to setting (ocean-ocean or ocean-continent collision; forearc, arc or back-arc). In general, however, fertile compositions seem to be more common in continental arcs and to be accompanied by higher equilibration temperatures. Ultra-refractory peridotites appear to be most common along oceanic forearcs and give generally lower temperatures in the range 950-1050 ºC. Ultra-refractory harzburgites sampled in subduction settings are chemically very similar to the ultra-refractory peridotites found as xenoliths in ocean islands. Both rock types compare quite well with the residues from experiments on the formation of primitive arc magmas. The formation of such magmas and their ultra-refractory harzburgite residues requires melting beyond the stability of clinopyroxene. Such high degrees of partial melting are probably achieved in two stages. The first stage is likely to take place as decompression melting along mid-ocean ridges or in back-arc spreading centers, whereas the second stage seems to require fluid-fluxed melting in the mantle wedge. Large degrees of melting may also be achieved in other types of settings if temperatures are sufficiently high. However, the common occurrence of ultra-refractory harzburgites together with melts generated from a strongly depleted precursor in active arcs is an argument in support of a subduction related origin of ultra-refractory harzburgites both in arc settings and in ocean islands. This implies that ultra-refractory arc material is common and may be recirculated by mantle convection. Because of their low density relative to “normal”, more fertile asthenospheric material, these ultra-refractory residues may rise as diapirs and intrude shallower parts of the asthenosphere, where they can accrete to younger oceanic plate.

• Simon, Nina Simone C & Podladtchikov, Iouri (2008). The effect of mantle composition on density in the extending lithosphere. Earth and Planetary Science Letters. ISSN 0012-821X. 272, p. 148–157. doi: 10.1016/j.epsl.2008.04.027. Full text in Research Archive
• Hopp, Jens; Trieloff, M.; Brey, G.P.; Woodland, A.B.; Simon, Nina S.C. & Wijbrans, J.R. [Show all 8 contributors for this article] (2008). Ar-40/Ar-39-ages of phlogopite in mantle xenoliths from South African kimberlites: Evidence for metasomatic mantle impregnation during the Kibaran orogenic cycle. Lithos. ISSN 0024-4937. 106(3-4), p. 351–364. doi: 10.1016/j.lithos.2008.09.001. Full text in Research Archive
• Simon, Nina Simone C; Neumann, Else Ragnhild; Bonadiman, C.; Coltorti, M.; Delpech, G. & Gregoire, M. [Show all 7 contributors for this article] (2008). Ultra-refractory domains in the oceanic mantle lithosphere sampled as mantle xenoliths at ocean islands. Journal of Petrology. ISSN 0022-3530. 49(6), p. 1223–1251. doi: 10.1093/petrology/egn023. Full text in Research Archive Show summary

  Many peridotite xenoliths sampled at ocean islands appear to have strongly refractory major element and modal compositions. In order to better constrain the chemistry, abundance and origin of these ultra-refractory rocks we compiled a large number of data for xenoliths from 9 different groups of ocean islands. The xenoliths were filtered petrographically for signs of melt infiltration and modal metasomatism and the samples affected by these processes were excluded. Most ocean islands are dominated by ultra-refractory harzburgites. Exceptions are Hawaii and Tahiti peridotites which are more fertile and contain primary clinopyroxene, and Cape Verde, which contains both ultra-refractory and more fertile xenoliths. Ultra-refractory harzburgites are characterized by the absence of primary clinopyroxene, low whole rock Al2O3, CaO, FeO/MgO and HREE concentrations, low Al2O3 in orthopyroxene (generally <3 wt%), high Cr# in spinel (0.3-0.8) and high forsterite contents in olivine (averages >91.5). They are therefore on average significantly more refractory than peridotites dredged and drilled from mid-ocean ridges and fracture zones. Moreover, their compositions resemble those of oceanic fore-arc peridotites. The formation of ultra-refractory ocean island harzburgites requires potential temperatures above those normally observed at modern mid-ocean ridges, and/or fluid fluxed conditions. Some ultra-refractory ocean island harzburgites give high Os model ages (up to 3300 Ma), showing that their formation significantly pre-dates the oceanic crust in the area. A genetic relationship with the host plume is considered unlikely based on textural observations, equilibration temperatures and pressures, inferred physical properties, and long-term depleted Os and Sr isotope ratios of some of the harzburgites. Although we do not exclude the possibility that some ultra-refractory ocean island harzburgites have formed at mid-ocean ridges, we favor a model in which they formed in a process spatially and temporally unrelated to the formation of the oceanic plate and the host plume. They most likely represent residues of ancient large degree melting events, possibly during periods of enhanced arc magmatism and crust formation. Due to their whole rock compositions, ultra-refractory harzburgites have low densities and very high viscosities, and will tend to accumulate at the top of the convecting mantle. They may be preserved as fragments in the convecting mantle over long periods of time and be preferentially incorporated into newly formed lithosphere.

• Simon, Nina Simone C; Carlson, R. W.; Pearson, D.G. & Davies, G.R. (2007). The origin and evolution of the Kaapvaal cratonic lithospheric mantle. Journal of Petrology. ISSN 0022-3530. 48, p. 589–625. Full text in Research Archive

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• Røyne, Anja; Simon, Nina; Nyheim, Martine & Haynes, Helene Victoria (2025). Tverrfaglig kompetanse og bærekraftskompetanse: hvordan fremme integrasjon i prosjektarbeid? Full text in Research Archive
• Røyne, Anja & Simon, Nina (2025). Including consumer behavior in assessing the systems wide environmental impacts of business decisions in sustainability transitions. Full text in Research Archive
• Mørkved, Pål Tore; Soldal, Jostein; Dörsch, Peter; Noort, Reinier Van; Simon, Nina Simone C & Bakken, Lars (2016). Soil pH regulation and reduction of N2O emissions by mafic rock application. Full text in Research Archive
• Räss, L.; Yarushina, Viktoriya M.; Simon, Nina Simone C & Podladchikov, Y.Y. (2014). The importance of poromechanics for CO2 storage integrity. Full text in Research Archive
• Mørkved, Pål Tore; Simon, Nina Simone C; Dörsch, Peter & Bakken, Lars (2013). Combined N2O mitigation and CO2 trapping: A step toward a carbon negative agriculture? Full text in Research Archive
• Mørkved, Pål Tore; Simon, Nina Simone C; Dörsch, Peter & Bakken, Lars (2013). Combined N2O mitigation and CO2 trapping: A step toward a carbon negative agriculture? Full text in Research Archive
• Simon, Nina Simone C (2013). Fluid focusing and breaching of low permeability layers in reacting and visco-elasto-plastically deforming reservoir rocks. European Geosciences Union General Assembly Abstracts. 15. Full text in Research Archive
• Simon, Nina Simone C & Podladchikov, Yuri Y. (2013). A consistent physical model for the formation of focused flow channels (chimneys) through intra-reservoir shales. The 7th Trondheim CCS Conference (TCCS-7). Full text in Research Archive
• Simon, Nina S.C.; Podladchikov, Yuri Y. & Johansen, Harald (2011). Dynamic permeability due to physical coupling of reactive CO2-flow and deformation. Full text in Research Archive
• Simon, Nina S.C. & Haug, T. Anette (2011). Dissolution and carbonation of mechanically activated olivine - implications for in-situ CO2 sequestration in mafic and ultramafic rocks? Full text in Research Archive
• Simon, Nina S.C. (2011). A phase change model for (on of) the LAB(s). Full text in Research Archive
• Simon, Nina S.C.; Løberg, Magnus Bjørnsen; Podladchikov, Yuri Y. & Huismans, Ritske (2011). Is enhanced heat and tracer transfer an important process in deep geothermal systems? Full text in Research Archive
• Simon, Nina S.C.; Johansen, Harald & Podladchikov, Yuri Y. (2011). Dynamic behaviour of porosity and permeability as a response to CO2 injection. Full text in Research Archive
• Simon, Nina S.C.; Semprich, Julia & Podladchikov, Yuri Y. (2011). A phase transition model for basins. Full text in Research Archive
• Simon, Nina Simone C; Yarushina, Viktoriya M. & Podladchikov, Yuri P. (2010). Fluid-rock interaction in deep goethermal systems. Full text in Research Archive
• Simon, Nina Simone C; Vrijmoed, Johannes Christiaan; Yarushina, Viktoriya M. & Podladchikov, YY (2010). Fluid-rock interaction in deep geothermal systems. Full text in Research Archive
• Simon, Nina Simone C & Podladchikov, Y.Y. (2010). Enhanced heat transfer by intermittent porous flow. Full text in Research Archive
• Loberg, Magnus; Huismans, Ritske S.; Simon, Nina Simone C & Podladchikov, YY (2010). Fluid-rock interaction in deep geothermal systems. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Vrijmoed, Johannes Christiaan (2010). Geodynamic significance of incomplete reactions: A case study of coronas from the Norwegian Caledonides. Full text in Research Archive
• Simon, Nina Simone C & Semprich, Julia (2010). Compositional buoyancy in the crust and upper mantle – implications for vertical motions. Full text in Research Archive
• Simon, Nina Simone C (2010). Ultra-refractory peridotite xenoliths: what’s their story? Full text in Research Archive
• Simon, Nina Simone C & Podladchikov, YY (2010). Interplay of lower crustal metamorphism and continental lithosphere dynamics. Full text in Research Archive
• Semprich, Julia; Podladtchikov, Iouri & Simon, Nina Simone C (2009). Compression, reaction activation and phase transitions: How to form a basin. Geochimica et Cosmochimica Acta. ISSN 0016-7037. 73(13), p. A1194–A1194. Full text in Research Archive
• Gac, Sebastien; Huismans, Ritske S.; Podladchikov, YY; Simon, Nina Simone C & Semprich, Julia (2009). Can phase changes be at the origin of the large subsidence of Barents Sea basins? Insights from density modelling. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Podladtchikov, Iouri (2009). Compression, reaction activation and phase transitions: how to form a basin. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Podladchikov, Yuri (2008). The effect of pressure, temperature and composition on physical rock properties. Full text in Research Archive
• Beuchert, Marcus Johannes; Podladchikov, YY; Simon, Nina Simone C & Rüpke, Lars Heimuth (2008). Viscoelastic modeling of craton stability. Full text in Research Archive
• Beuchert, Marcus Johannes; Podladchikov, YY & Simon, Nina Simone C (2008). Phase transitions and thickness of the oceanic lithosphere. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Podladchikov, Yuri (2008). Compression and subsequent phase transitions as a mechanism for basin formation. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Podladchikov, Yuri (2008). The effect of pressure, temperature and composition on physical rock properties. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Podladchikov, Yuri (2008). Evaluation of phase transitions in the lower crust as mechanism for basin formation. Full text in Research Archive
• Beuchert, Marcus Johannes; Podladchikov, YY & Simon, Nina Simone C (2008). Stability of the Large Low Shear Velocity Provinces (LLSVPs) in the lower mantle. Full text in Research Archive
• Neumann, Else Ragnhild & Simon, Nina Simone C (2008). Ultra-Depleted Domains in the Oceanic Mantle Lithosphere. Full text in Research Archive
• Semprich, Julia; Simon, Nina Simone C & Podladtchikov, YY (2008). The effect of pressure, temperature and composition on physical rock properties. Geochimica et Cosmochimica Acta. ISSN 0016-7037. 72, p. A847–A847. Full text in Research Archive
• Neumann, Else Ragnhild & Simon, Nina Simone C (2008). Ultra-depleted domains in the oceanic mantle lithosphere. Geochimica et Cosmochimica Acta. ISSN 0016-7037. 72, p. A677–A677. Full text in Research Archive
• Hartz, Ebbe Hvidegård; Podladchikov, Yuri; Medvedev, Sergei; Faleide, Jan Inge & Simon, Nina Simone C (2007). ARCTIC ‘OUT-OF-SEQUENCE’ BASINS: NEW DATA AND MODELS FOR THE EAST GREENLAND AND BARENTS SEA BASINS. Full text in Research Archive
• Simon, Nina Simone C; Podladchikov, YY & Hartz, Ebbe Hvidegård (2007). Subsidence in the East Barents Basin: Are mineral phase transitions the clue? Full text in Research Archive
• Simon, Nina Simone C; Neumann, Else Ragnhild; Medvedev, Sergei & Podladchikov, YY (2007). Isostatic Response of Strongly Extended Continental Lithosphere to Refertilization. Full text in Research Archive
• Simon, Nina Simone C & Semprich, Julia (2007). Crustal density as a function of pressure, temperature and composition. Full text in Research Archive
• Simon, Nina Simone C; Rüpke, Lars Helmuth & Podladchikov, YY (2007). Quantifying the effect of mantle phase transitions and application to the Vøring basin, off-shore Norway. Full text in Research Archive
• Simon, Nina Simone C; Beuchert, Marcus Johannes & Podladchikov, YY (2007). What determines the thickness of the lithosphere? Full text in Research Archive
• Neumann, Else Ragnhild; Simon, Nina Simone C; Bonadiman, C.; Coltorti, M.; Delpech, G. & Gregoire, M. (2007). Ultra-refractory domains in the oceanic lithosphere: evidence from major element and modal relationships in mantle xenoliths from ocean islands. Full text in Research Archive Show summary

  We have compiled a database for major element and modal data of mantle harzburgite and lherzolite xenoliths from different ocean islands. The xenoliths fall in two main categories. Xenoliths showing no petrographic evidence of metasomatism (OI1) from the Canary Islands, Kerguelen, Cape Verde and Samoa are ultra-depleted spinel harzburgites. These xenoliths formed by high degrees of partial melting leading to total exhaustion of cpx. Small amounts of cpx observed in these rocks (mainly $<$3 vol. percent) have partly formed through exsolution from opx followed by recrystallization, and partly through reactions between mantle wall-rocks and LREE-enriched metasomatic melts. Peridotites from the same islands (and the Azores) which show petrographic evidence of metasomatism (OI2) partly fall within the major element and modal range of OI1 xenoliths, partly they are less refractory. On average, the OI1 xenoliths are significantly more refractory than peridotites collected along mid-ocean ridges and fracture zone (MORP), although the most refractory mid-ocean ridge peridotites fall within the OI1 range. Although the OI1 xenoliths show indications of metasomatism in trace elements, Na2O, and radiogenic isotopes, their major element and modal compositions seem to be essentially unaffected by metasomatic processes. The ultra-depleted nature of the OI1 xenoliths is also reflected in the Fo-contents in ol, and in the HREE and MREE in opx. OI2 xenoliths are OI1 rocks, many of which have been metasomatized to the degree that major element and modal phase compositions have been modified. The other main category, consisting of harzburgite and lherzolite xenoliths collected in Hawaii, Tahiti and Grande Comore (OIcpx) are significantly less refractory that the OI1 xenoliths and show similarities to MORP. Many of these xenoliths contain significant amounts of cpx (up to 20 vol. %), and contain primary cpx, indicating only moderate amounts of partial melting (or extensive re-fertilization). Unradiogenic Os isotopes and high Re-Os model ages suggest that OI1 and OI1cpx rocks from some islands are much older than the abyssal lithosphere in which they are found. P-T estimates of 0.7-1.3 GPa and 850-1200C indicate that the OI1 xenoliths last equilibrated at depths corresponding to $>$80 Ma old oceanic lithospheric mantle. We interpret the ultra-depleted xenoliths as fragments of “exotic” material trapped in the oceanic mantle lithosphere. Major element similarities to some series of oceanic sub-arc mantle, and significant differences from continental xenolith series, makes it most likely that the ultra-refractory OI1 peridotites represent recycled abyssal mantle. The large proportion of ultra-refractory peridotite xenoliths in ocean islands, and the presence of such rocks also along some mid-ocean ridges and in sub-arc mantle, suggest that ultra-refractory material may be important ingredients in the convecting mantle. Because of their ultra-depleted chemistry the OI1 type harzburgites will have relatively low densities and are therefore buoyant relative to less refractory mantle rock types. Their high solidus temperatures make the OI1 xenoliths immune to further partial melting (sterile).

• Hartz, Ebbe Hvidegård; Podladchikov, Yuri; Medvedev, Sergei; Faleide, Jan Inge & Simon, Nina Simone C (2007). Force, energy and mass balanced basin models: New concepts and Arctic examples. Full text in Research Archive
• Hartz, Ebbe Hvidegård; Podladchikov, Yuri; Medvedev, Sergei; Faleide, Jan Inge & Simon, Nina Simone C (2007). The effects of energy balanced metamorphic reactions and far-field tectonic and gravitational forces on basin formation. Full text in Research Archive
• Simon, Nina Simone C & Semprich, Julia (2007). Crustal density as a function of pressure, temperature and composition. Full text in Research Archive
• Hartz, Ebbe Hvidegård; Podladchikov, Yuri; Medvedev, Sergei; Faleide, Jan Inge & Simon, Nina Simone C (2007). The effects of energy balanced metamorphic reactions and far-field tectonic and gravitational forces on basin formation. Full text in Research Archive
• Simon, Nina Simone C; Podladtchikov, Iouri & Rüpke, Lars Helmuth (2007). Lithospheric geodynamics with thermo-chemical density anomalies and mineral phase transitions switched on. Geochimica et Cosmochimica Acta. ISSN 0016-7037. 71, p. A940–A940. Full text in Research Archive
• Beuchert, Marcus Johannes; Podladchikov, YY; Rüpke, Lars Helmuth & Simon, Nina Simone C (2007). Numerical modeling of craton stability and formation. Full text in Research Archive
• Beuchert, Marcus Johannes; Podladchikov, YY; Rüpke, Lars Helmuth & Simon, Nina Simone C (2007). Modeling of craton stability using a viscoelastic rheology. Full text in Research Archive
• Rüpke, Lars Helmuth; Simon, Nina Simone C & Podladtchikov, Iouri (2007). Studies of continent stability using joint petrological and geodynamical models. Geochimica et Cosmochimica Acta. ISSN 0016-7037. 71, p. A858–A858. Full text in Research Archive
• Neumann, Else Ragnhild; Simon, Nina Simone C; Bonadiman, C; Coltort, M; Delpech, G & Gregoire, M (2007). Extremely refractory oceanic lithospheric mantle and its implications for geochemical mass balance. Geochimica et Cosmochimica Acta. ISSN 0016-7037. 71, p. A712–A712. Full text in Research Archive
• Beuchert, Marcus Johannes; Podladchikov, YY; Rüpke, Lars Helmuth & Simon, Nina Simone C (2007). Influence of rheology on craton stability - Implications from numerical modeling. Full text in Research Archive
• Neumann, Else Ragnhild & Simon, Nina Simone C (2006). The abyssal Mantle Lithosphere as indicated by Xenoliths from Ocean Islands. Full text in Research Archive Show summary

  When studying metasomatism and other processes in the abyssal mantle, it is essential to know the composition of the unmodified lithospheric mantle. Most information available on the abyssal lithospheric mantle has been obtained on the basis of peridotites sampled through dredging and drilling along mid ocean ridges and fracture zones. However, the compositions of such samples have been modified through serpentinization, marine weathering, metamorphism, melt infiltration and deformation. Furthermore, such samples represent only the uppermost part of the abyssal mantle, and thus cannot give information about potential vertical zoning. An alternative approach is through peridotite massifs and ophiolites, but also these rocks have experienced a complex set of processes after initial formation, and the origin of a given unit (oceanic or continental) is not always easy to determine. As a matter of fact, it is doubtful if any of the units for which data are available represent abyssal mantle. A third setting where information about the abyssal mantle lithosphere may be obtained is ocean islands where mantle xenoliths are commonly brought to the surface during volcanic eruptions. Although the intraplate magmatism forming ocean islands leads to metasomatism of the underlying abyssal lithosphere, and there is evidence that there may be fragments of continental lithosphere beneath some ocean islands (e.g. Cape Verde), mantle xenoliths from ocean islands are proving to be a fruitful source of information about the abyssal mantle lithosphere. The mantle xenolith series from many ocean islands include samples that have mainly suffered cryptic metasomatism so that their pre-metasomatism chemistry is preserved in the most abundant major elements (SiO2, MgO, FeO and CaO) and in their modal phase proportions. These parameters are most robust against metasomatism. We use major element and modal data on spinel harzburgite and lherzolite xenoliths from different oceanic islands (Canary Islands, Cape Verde, Azores, Kerguelen, Hawaii, Tahiti, Samoa) in order to throw light on the compositional character of the abyssal mantle lithosphere. The least metasomatized xenoliths from different ocean islands are, on average, significantly more refractory (most of these samples fall in the range 44-49 wt% MgO, 0.4-1.1 wt% CaO, 1.5 wt% Al2O3) than peridotites sampled along mid-ocean ridges and fracture zones (40-48 wt% MgO, 0.3-2.5 wt% CaO, 0.3-4.0 wt% Al2O3; with the least refractory suites along slow-spreading ridges). The major element and modal compositions of the mantle xenoliths from ocean islands indicate that they represent residues after partial melting into the olivine+orthopyroxene±spinel stability field. Small amounts of clinopyroxene (<2 volume %) found in these samples appear to have formed as the results of exsolution from orthopyroxene. Comparison with experimental data suggests partial melting at 1 GPa. Samples with >>65 % olivine and significant amounts of clinopyroxene generally show abundant evidence of metasomatism, including clinopyroxene-producing reactions. The peridotite series xenoliths from Hawaii and Tahiti are anomalous as they are less refractory (on the average, lower MgO and modal olivine, higher FeOtotal, CaO, TiO2, Al2O3 and modal clinopyroxene). The observed major element and modal differences between spinel harzburgite/lherzolite series collected in ocean islands and along mid-ocean ridges and fracture zones are interpreted as (1) the result of partial melting at higher pressures of the former (leading to exhaustion of clinopyroxene at a lower olivine-content), and (2) melt infiltration and refertilization which has affected the shallow mantle close to the mid-ocean ridges, but not the deeper parts of the upwelling mantle that has moved away from the mid-ocean ridge zone without being subjected to the refertilization processes in the main ridge zone.

• Podladchikov, Yuri; Rüpke, Lars Helmuth; Schmalholz, Stefan Markus & Simon, Nina Simone C (2006). Late syn-rift (65-55 Ma) uplift in the Voring Basin, Norwegian Sea - was it a 'hot' or a 'cold' event? Full text in Research Archive
• Simon, Nina Simone C & Podladchikov, Yuri (2006). The effect of mantle petrology on lithosphere dynamics during extension. Full text in Research Archive
• Simon, Nina Simone C & Neumann, Else-Ragnhild (2006). A strongly melt-deprived oceanic lithosphere: what does it mean for geodynamics? Full text in Research Archive
• Simon, Nina Simone C; Podladchikov, Yuri; Rüpke, Lars Helmuth & Neumann, Else-Ragnhild (2005). Craton stability and basin formation - The influence of mantle petrology on large scale geodynamics. Full text in Research Archive
• Rüpke, Lars Helmuth; Simon, Nina Simone C & Podladchikov, Yuri (2005). A Modeled Confirmation That Cratons are Strong, Cold, and Long-Lived. Full text in Research Archive
• Simon, Nina Simone C (2005). Evidence for formation and modification of the Kaapvaal craton (Southern Africa) in Archaean subduction zones. Bollettino del gruppo di lavoro sulle ofioliti mediterranee. ISSN 0391-2612. 30. Full text in Research Archive
• Simon, Nina Simone C & Podladchikov, Yuri (2005). The influence of mantle petrology on basin subsidence during rifting. Transactions of the American Geophysical Union. Full text in Research Archive
• Simon, Nina Simone C (2005). Re-Os isotope evidence for orthopyroxene addition to the Kaapvaal cratonic mantle in (Archaean) subduction zones. Geophysical Research Abstracts. ISSN 1029-7006. 7, p. 03534–03534. Full text in Research Archive
• Laitala, Kirsi; Sigaard, Anna Schytte; Simon, Nina; Rubach, Synnøve & Sadeleer, Irmeline de (2025). Mot en mer bærekraftig garderobe: Forbrukerperspektiver, markedspotensial og faren for grønnvasking i bruktmarkedet. OsloMet - storbyuniversitetet. ISSN 9788270635825. Full text in Research Archive Show summary

  Vi har undersøkt årsakene til den lave gjenbruksgraden av tekstiler i Norge og identifisert flere barrierer gjennom litteraturgjennomganger, kundeundersøkelser, workshops og intervjuer. For å øke gjenbruk foreslås det å utfordre fordommer om gjenbruksbutikker, ulike former for promotering, og forbedre butikkopplevelsen og tilgjengeligheten. Kundeundersøkelsen viser at bruktkjøp utgjør en betydelig andel av anskaffelsene, noe som indikerer delvis erstatning av nykjøp. Samtalene med prosjektaktørene har avdekket utfordringer som manglende tilgjengelighet av kvalitetsklær, høye kostnader for innsamling og sortering, og kompliserende lovverk. Det er behov for bedre samarbeid mellom verdikjedeaktører og investeringer i digitale løsninger. Arbeidsgruppen bestående av bedriftspartnere i prosjektet foreslår å fjerne merverdiavgift på reparasjoner, støtte bærekraftige produsenter, og sikre høyere kvalitet på varer, samt reguleringer for rene materialer og produktmerking. For å unngå grønnvasking må markedsføringen av gjenbruk være nøye vurdert, med dokumentasjon av bærekraftspåstander.

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