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Visar resultat 1 - 5 av 11 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Hydrogen in nominally anhydrous silicate minerals : Quantification methods, incorporation mechanisms and geological applications

   Författare :Franz A. Weis; Henrik Skogby; Peter Lazor; Jannick Ingrin; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NAMs; clinopyroxene; hydrogen; hydrothermal pressure; magmatic water content; zoisite; OH-dipole; Raman spectroscopy; FTIR; luminescence; proton-proton scattering;

   Sammanfattning : The aim of this thesis is to increase our knowledge and understanding of trace water concentrations in nominally anhydrous minerals (NAMs). Special focus is put on the de- and rehydration mechanisms of clinopyroxene crystals in volcanic systems, how these minerals can be used to investigate the volatile content of mantle rocks and melts on both Earth and other planetary bodies (e. LÄS MER

3. 2. Magma plumbing architecture in Indonesia and the North Atlantic Igneous Province

   Författare :Börje Dahrén; Valentin R Troll; Abigail K. Barker; Steffi Burchardt; Ben Ellis; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magma plumbing; geothermobarometry; plagioclase; clinopyroxene; magma-crust interaction; hazard mitigation; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

   Sammanfattning : 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. LÄS MER

4. 3. Volcanism at the tip of a propagating rift : the Heimaey volcanic centre, south Iceland

   Författare :Hannes B. Mattsson; Armann Höskuldsson; Alasdair Skelton; Sigurdur Steinthorsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geology; Volcanology; Petrology; Heimaey; Vestmannaeyjar; Propagating rift; Phreatomagmatic; Diatreme; Tumuli; Earth sciences; Geovetenskap;

   Sammanfattning : Primary magmas are generated by 4-6% partial melting near the garnet-spinel stability fields beneath Heimaey (i.e. 80-65 km depth). The magmas fractionate 31% olivine and clinopyroxene en-route to ponding at the base of the crust (and forming a parental Vestmannaeyjar magma). LÄS MER

5. 4. The Alnö alkaline and carbonatitic complex, east central Sweden - a petrogenetic study

   Författare :Jaana Hode Vuorinen; Alasdair Skelton; Ulf Hålenius; Stefan Claesson; Ian Parsons; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbonatite; alkaline; Alnö; geochemistry; isotope; Earth sciences; Geovetenskap;

   Sammanfattning : The Alnö complex on the central Swedish east coast is composed of a main composite intrusion (the main intrusion) and four smaller satellite intrusions (Söråker, Sälskär, Långharsholmen and Båräng) distributed around the main intrusion on Alnö Island and on the mainland north of the island. The major rock types exposed within the complex are melilitolite, pyroxenite, ijolite series (melteigite-ijolite-urtite), nepheline syenite, carbonatite and alnöite dykes. LÄS MER

7. 5. Hydrogen diffusion and storage mechanisms in diopside

   Författare :Rickard Sundvall; Henrik Skogby; Alasdair Skelton; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mineralogy; Mineralvetenskap; mineralogi; petrologi och geokemi; Mineralogy; Petrology and Geochemistry;

   Sammanfattning : Hydrogen is a widespread trace element in many nominally anhydrous minerals (minerals without water or hydroxyl ions in their structural formula) from the Earth's crust and mantle. The hydrogen is normally incorporated in the form of hydroxyl ions and can be regarded as structurally bound water. LÄS MER