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Papers by Nina Søager

Research paper thumbnail of Thermodynamic modelling of continental arc-adjacent magmatism: the Loicas Trough, N. Patagonia, Argentina

Contributions to Mineralogy and Petrology, Dec 17, 2023

Research paper thumbnail of Quaternary basaltic volcanism in the Payenia volcanic province, Argentina:geochemical constraints on sources and magmatic processes in the generation of backarc to intraplate basaltic magmas

Research paper thumbnail of 苏鲁造山带中部晚中生代裂谷作用与深部动力机制<bold>——</bold>来自灵山岛的记录

Research paper thumbnail of Geochemistry of Late Permian basalts from boreholes in the Sichuan Basin, SW China: Implications for an extension of the Emeishan large igneous province

Research paper thumbnail of Thallium isotope constraints on subduction recycling in the Southern Andes Arc

Research paper thumbnail of Delamination of lithopheric mantle in the central Sulu orogenic belt in early Cretaceous: evidence from trachyandesites and lamprophyres of new scientific drilling LK-1

Goldschmidt2022 abstracts, 2022

Research paper thumbnail of Low-Ti basalts from the Faroe Islands constrain the early Iceland depleted plume component

EGU General Assembly Conference Abstracts, Apr 1, 2009

Research paper thumbnail of Constraints on lithosphere-asthenosphere melt mixing in basaltic intraplate volcanism from olivine melt inclusions from southern Payenia, Argentina

Lithos, Jun 1, 2018

We present major and trace element compositions of melt inclusions from three alkali basalts from... more We present major and trace element compositions of melt inclusions from three alkali basalts from the Río Colorado volcanic field in the Payenia backarc province, Argentina. Modeling of diffusion profiles around the inclusions showed that most inclusions equilibrated less than 14 days after formation, indicating a short crustal residence time for the magmas and nearly direct ascent through the crust. Despite overlapping host rock isotopic compositions, the inclusions show a large variation in their degree of enrichment, and display trends that we interpret as mixing between asthenospheric OIB-type low K 2 O-high Nb/U melts and enriched high K 2 Olow Nb/U lithospheric mantle melts similar in composition to alkaline lamprophyres. The low Nb/U magmas are excessively enriched in the elements Cs,

Research paper thumbnail of South-to-north pyroxenite–peridotite source variation correlated with an OIB-type to arc-type enrichment of magmas from the Payenia backarc of the Andean Southern Volcanic Zone (SVZ)

Contributions to Mineralogy and Petrology, Dec 5, 2016

and high Th/La ratios, which suggest a component of upper continental crust (UCC) in the metasoma... more and high Th/La ratios, which suggest a component of upper continental crust (UCC) in the metasomatizing agent of the northern mantle. However, the addition to the mantle source of crustal materials or varying oxidation state cannot explain the variation in Mn and Mn/Fe of the melts and olivines along Payenia. Instead, the correlation between Mn/Fe ol and whole-rock (wr) trace element compositions is evidence of two-component mixing of melts derived from peridotite mantle source enriched by slab fluids and UCC melts and a pyroxenite mantle source with an EM1-type trace element signature. Very low Ca/Fe ratios (~1.1) in the olivines of the peridotite melt component and lower calculated partition coefficients for Ca in olivine for these samples are suggested to be caused by higher H 2 O contents in the magmas derived from subduction zone enriched mantle. Well-correlated Mn/Fe ratios in the wr and primitive olivines demonstrate that the Mn/Fe wr of these basalts that only fractionated olivine and chromite reflects the Mn/Fe of the primitive melts and can be used as a proxy for the amount of pyroxenite melt in the magmas. Using Mn/Fe wr for a large dataset of primitive Payenia rocks, we show that decreasing Mn/Fe wr is correlated with decreasing Mn and increasing Zn/Mn as expected for pyroxenite melts.

Research paper thumbnail of Origin of Silicic volcanism in the North Patagonian Rear Arc

Goldschmidt2022 abstracts, 2022

Research paper thumbnail of EM1 pyroxenite melts from the SCLM: a possible source of the enriched isotope signatures in Andean NSVZ arc magmas

Research paper thumbnail of The role of pyroxenite sources in theorigin of the Payenia volcanicprovince, Argentina: insights fromtrace elements in olivine

2359 The role of pyroxenite sources in the origin of the Payenia volcanic province, Argentina: in... more 2359 The role of pyroxenite sources in the origin of the Payenia volcanic province, Argentina: insights from trace elements in olivine NINA SØAGER1*, MAXIM PORTNYAGIN1, KAJ HOERNLE1 AND DIETER GARBE-SCHÖNBERG2 1GEOMAR, Helmholtz Centre for Ocean Research, Wischhofsstraße 1-3, 24148 Kiel, Germany (*correspondence: ns@ign.ku.dk) 2Christian-Albrechts-Universität zu Kiel, Christian-AlbrechtsPlatz 4, 24118 Kiel, Germany

Research paper thumbnail of アルゼンチン,メンドーサ南部のPayenia火山区:背弧環境におけるOIBマントル上昇

Research paper thumbnail of Asthenospheric versus lithospheric sources of the Payenia basalts (Argentina): Constraints from Al-in olivine thermometry and melt inclusions

Research paper thumbnail of Delamination of lithopheric mantle in the central Sulu orogenic belt in early Cretaceous: evidence from trachyandesites and lamprophyres of new scientific drilling LK-1

Goldschmidt2022 abstracts, 2022

Research paper thumbnail of Recycled Crustal Components of the Iceland Plume Centre: Ultra-Dehydrated Crust and Oxidised Water-Bearing Fertile Mantle

Journal of Petrology

Primitive basalts erupted mainly above the proposed centre of the Iceland plume have been analyse... more Primitive basalts erupted mainly above the proposed centre of the Iceland plume have been analysed geochemically. The data shed light on the distribution of plume heterogeneities and constrain their nature and origin. Low Ca (down to 1420 ppm) olivine macrocrysts and chromite inclusions in Snæfell rocks of the Eastern Flank Zone indicate that the magmas were hydrous (c. 2 wt% H2O) and relatively oxidised (fO2 = c. ΔQMF+1). Al-in-olivine crystallisation temperatures indicate that magmas from central Iceland magmas are not hotter than from other parts of Iceland. Some Gæsafjöll rocks with high Nb/U = 110–120 from the Northern Rift Zone represent magmas widespread in Iceland that are also characterized by low Ba/La and high La/U, La/Th, Nb/Th and Ce/Pb. They reflect a mantle component with Nb/U ≈ 200 present in many basalts of all rift zones. This mantle apparently consists of peridotite refertilised by ultra-dehydrated recycled oceanic crust. This component is in clear contrast to the...

Research paper thumbnail of Contrasting sources for North Atlantic margin and Iceland basalts:a discussion of effects from melting regime and plume composition

Research paper thumbnail of Records of magma-crust interaction as constraints on the sub-basalt basement beneath the Faroe Islands

Research paper thumbnail of Late Mesozoic rifting and its deep dynamic mechanisms in the central Sulu orogenic belt: Records from Lingshan Island

Science China Earth Sciences

Research paper thumbnail of A geochemical probe into the magma plumbing system and the ancient continental crust underlying the Faroe Islands Basalt Group

Magma plumbing systems represent the physical framework of magma transport and storage from the s... more Magma plumbing systems represent the physical framework of magma transport and storage from the source region in the mantle, through the crust, until reaching the surface in a volcanic eruption. Characterising the different aspects of magma plumbing, in particular the distribution of magma storage zones throughout the crust, is of key importance to better understand the behaviour of individual volcanoes. In particular, shallow crustal magma storage and associated magma-crust interaction processes could potentially explain some of the worlds most unpredictable and explosive volcanoes. This thesis studies magma plumbing architecture in the Sunda Arc (Indonesia), and the North Atlantic Igneous Province, based on elemental and isotope geochemistry, and derived petrological modelling.In this study, I have employed petrological models, so called geothermobarometers, to calculate pressures and temperatures (P-T) of crustal magma storage. Geothermobarometers are calibrated thermodynamic for...

Research paper thumbnail of Thermodynamic modelling of continental arc-adjacent magmatism: the Loicas Trough, N. Patagonia, Argentina

Contributions to Mineralogy and Petrology, Dec 17, 2023

Research paper thumbnail of Quaternary basaltic volcanism in the Payenia volcanic province, Argentina:geochemical constraints on sources and magmatic processes in the generation of backarc to intraplate basaltic magmas

Research paper thumbnail of 苏鲁造山带中部晚中生代裂谷作用与深部动力机制<bold>——</bold>来自灵山岛的记录

Research paper thumbnail of Geochemistry of Late Permian basalts from boreholes in the Sichuan Basin, SW China: Implications for an extension of the Emeishan large igneous province

Research paper thumbnail of Thallium isotope constraints on subduction recycling in the Southern Andes Arc

Research paper thumbnail of Delamination of lithopheric mantle in the central Sulu orogenic belt in early Cretaceous: evidence from trachyandesites and lamprophyres of new scientific drilling LK-1

Goldschmidt2022 abstracts, 2022

Research paper thumbnail of Low-Ti basalts from the Faroe Islands constrain the early Iceland depleted plume component

EGU General Assembly Conference Abstracts, Apr 1, 2009

Research paper thumbnail of Constraints on lithosphere-asthenosphere melt mixing in basaltic intraplate volcanism from olivine melt inclusions from southern Payenia, Argentina

Lithos, Jun 1, 2018

We present major and trace element compositions of melt inclusions from three alkali basalts from... more We present major and trace element compositions of melt inclusions from three alkali basalts from the Río Colorado volcanic field in the Payenia backarc province, Argentina. Modeling of diffusion profiles around the inclusions showed that most inclusions equilibrated less than 14 days after formation, indicating a short crustal residence time for the magmas and nearly direct ascent through the crust. Despite overlapping host rock isotopic compositions, the inclusions show a large variation in their degree of enrichment, and display trends that we interpret as mixing between asthenospheric OIB-type low K 2 O-high Nb/U melts and enriched high K 2 Olow Nb/U lithospheric mantle melts similar in composition to alkaline lamprophyres. The low Nb/U magmas are excessively enriched in the elements Cs,

Research paper thumbnail of South-to-north pyroxenite–peridotite source variation correlated with an OIB-type to arc-type enrichment of magmas from the Payenia backarc of the Andean Southern Volcanic Zone (SVZ)

Contributions to Mineralogy and Petrology, Dec 5, 2016

and high Th/La ratios, which suggest a component of upper continental crust (UCC) in the metasoma... more and high Th/La ratios, which suggest a component of upper continental crust (UCC) in the metasomatizing agent of the northern mantle. However, the addition to the mantle source of crustal materials or varying oxidation state cannot explain the variation in Mn and Mn/Fe of the melts and olivines along Payenia. Instead, the correlation between Mn/Fe ol and whole-rock (wr) trace element compositions is evidence of two-component mixing of melts derived from peridotite mantle source enriched by slab fluids and UCC melts and a pyroxenite mantle source with an EM1-type trace element signature. Very low Ca/Fe ratios (~1.1) in the olivines of the peridotite melt component and lower calculated partition coefficients for Ca in olivine for these samples are suggested to be caused by higher H 2 O contents in the magmas derived from subduction zone enriched mantle. Well-correlated Mn/Fe ratios in the wr and primitive olivines demonstrate that the Mn/Fe wr of these basalts that only fractionated olivine and chromite reflects the Mn/Fe of the primitive melts and can be used as a proxy for the amount of pyroxenite melt in the magmas. Using Mn/Fe wr for a large dataset of primitive Payenia rocks, we show that decreasing Mn/Fe wr is correlated with decreasing Mn and increasing Zn/Mn as expected for pyroxenite melts.

Research paper thumbnail of Origin of Silicic volcanism in the North Patagonian Rear Arc

Goldschmidt2022 abstracts, 2022

Research paper thumbnail of EM1 pyroxenite melts from the SCLM: a possible source of the enriched isotope signatures in Andean NSVZ arc magmas

Research paper thumbnail of The role of pyroxenite sources in theorigin of the Payenia volcanicprovince, Argentina: insights fromtrace elements in olivine

2359 The role of pyroxenite sources in the origin of the Payenia volcanic province, Argentina: in... more 2359 The role of pyroxenite sources in the origin of the Payenia volcanic province, Argentina: insights from trace elements in olivine NINA SØAGER1*, MAXIM PORTNYAGIN1, KAJ HOERNLE1 AND DIETER GARBE-SCHÖNBERG2 1GEOMAR, Helmholtz Centre for Ocean Research, Wischhofsstraße 1-3, 24148 Kiel, Germany (*correspondence: ns@ign.ku.dk) 2Christian-Albrechts-Universität zu Kiel, Christian-AlbrechtsPlatz 4, 24118 Kiel, Germany

Research paper thumbnail of アルゼンチン,メンドーサ南部のPayenia火山区:背弧環境におけるOIBマントル上昇

Research paper thumbnail of Asthenospheric versus lithospheric sources of the Payenia basalts (Argentina): Constraints from Al-in olivine thermometry and melt inclusions

Research paper thumbnail of Delamination of lithopheric mantle in the central Sulu orogenic belt in early Cretaceous: evidence from trachyandesites and lamprophyres of new scientific drilling LK-1

Goldschmidt2022 abstracts, 2022

Research paper thumbnail of Recycled Crustal Components of the Iceland Plume Centre: Ultra-Dehydrated Crust and Oxidised Water-Bearing Fertile Mantle

Journal of Petrology

Primitive basalts erupted mainly above the proposed centre of the Iceland plume have been analyse... more Primitive basalts erupted mainly above the proposed centre of the Iceland plume have been analysed geochemically. The data shed light on the distribution of plume heterogeneities and constrain their nature and origin. Low Ca (down to 1420 ppm) olivine macrocrysts and chromite inclusions in Snæfell rocks of the Eastern Flank Zone indicate that the magmas were hydrous (c. 2 wt% H2O) and relatively oxidised (fO2 = c. ΔQMF+1). Al-in-olivine crystallisation temperatures indicate that magmas from central Iceland magmas are not hotter than from other parts of Iceland. Some Gæsafjöll rocks with high Nb/U = 110–120 from the Northern Rift Zone represent magmas widespread in Iceland that are also characterized by low Ba/La and high La/U, La/Th, Nb/Th and Ce/Pb. They reflect a mantle component with Nb/U ≈ 200 present in many basalts of all rift zones. This mantle apparently consists of peridotite refertilised by ultra-dehydrated recycled oceanic crust. This component is in clear contrast to the...

Research paper thumbnail of Contrasting sources for North Atlantic margin and Iceland basalts:a discussion of effects from melting regime and plume composition

Research paper thumbnail of Records of magma-crust interaction as constraints on the sub-basalt basement beneath the Faroe Islands

Research paper thumbnail of Late Mesozoic rifting and its deep dynamic mechanisms in the central Sulu orogenic belt: Records from Lingshan Island

Science China Earth Sciences

Research paper thumbnail of A geochemical probe into the magma plumbing system and the ancient continental crust underlying the Faroe Islands Basalt Group

Magma plumbing systems represent the physical framework of magma transport and storage from the s... more Magma plumbing systems represent the physical framework of magma transport and storage from the source region in the mantle, through the crust, until reaching the surface in a volcanic eruption. Characterising the different aspects of magma plumbing, in particular the distribution of magma storage zones throughout the crust, is of key importance to better understand the behaviour of individual volcanoes. In particular, shallow crustal magma storage and associated magma-crust interaction processes could potentially explain some of the worlds most unpredictable and explosive volcanoes. This thesis studies magma plumbing architecture in the Sunda Arc (Indonesia), and the North Atlantic Igneous Province, based on elemental and isotope geochemistry, and derived petrological modelling.In this study, I have employed petrological models, so called geothermobarometers, to calculate pressures and temperatures (P-T) of crustal magma storage. Geothermobarometers are calibrated thermodynamic for...

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