Sökning: "petrologi och tektonik"

Visar resultat 21 - 25 av 34 avhandlingar innehållade orden petrologi och tektonik.

  1. 21. The High-Pressure Study on the Fe - O System: Thermodynamics and Phase Transitions of Iron Ferrite (FeFe2O4)

    Författare :Olga Shebanova; Peter Lazor; Viktor Struzhkin; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; high pressure; high temperature; thermodynamics; phase transitions; magnetite; Geovetenskap; Earth sciences; Geovetenskap; mineralogi; petrologi och tektonik; Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : Knowledge about the stability of phases and their relationships in the Fe-O system at high pressures and temperatures is essential in implications of the multifarious states of iron oxides for models of the evolution of the Earth. In this respect, the iron ferrite magnetite (FeFe2O4) plays a significant role since it participates in the control of geochemistry of ferric iron, and hence oxygen fugacity in the Earth`s deep interior. LÄS MER

  3. 22. Experimental Study of some Potassium and Sodium Bearing Aluminosilicates at High Temperatures and High Pressures

    Författare :Faramarz Tutti; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Phlogopite; Orthoclase; Jadeite; Albite; Calcium ferrite; Hollandite; Dehydroxylation; High temperature; High pressure; Lower mantle; Geochemistry; Geovetenskap; Earth sciences; Geovetenskap; mineralogi; petrologi och tektonik; Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : This dissertation presents the results of a high-temperature and high-pressure experimental study of some abundant aluminositicates, which are the main repositories for the two geochemically important elements, sodium and potassium, in the Earth's crust. Phase transitions of end member alkali feldspars and jadeite clinopyroxene are studied at high and ultrahigh pressures corresponding to the conditions between the transition zone and the deep Earth's lower mantle. LÄS MER

  4. 23. Processes of Magma-crust Interaction : Insights from Geochemistry and Experimental Petrology

    Författare :Frances M Deegan; Valentin R Troll; Luigi Dallai; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Canary Island magmatism; HP-HT experimental petrology; magma-crust interaction; Merapi volcano; radiogenic isotopes Sr; Nd; Pb ; stable isotopes O; B .; Solid earth geology and petrology; Berggrundsgeologi och petrologi; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : This work focuses on crustal interaction in magmatic systems, drawing on experimental petrology and elemental and isotope geochemistry. Various magma-chamber processes such as magma-mixing, fractional crystallisation and magma-crust interaction are explored throughout the papers comprising the thesis. LÄS MER

  5. 24. Elementfördelningen i samexisterande aktinolit, biotit och magnetit från Kiirunavaara-Luossavaara

    Författare :Tom Ekström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : .... LÄS MER

  7. 25. Geological Evolution of the Supracrustal Palaeoproterozoic Hamrånge Group: A Svecofennian Case Study

    Författare :Erik Ogenhall; Håkan Sjöström; Hans Annersten; Markku Väisänen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hamrånge; Ljusdal; Hagsta Gneiss Zone; geochemistry; geochronology; thermobarometry; metamorphism; fold-thrust belt.; Earth sciences; Geovetenskap; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : The work presented in this thesis utilizes several geological methods to investigate the origin and evolution of the supracrustal rocks in the Palaeoproterozoic Hamrånge Group (HG) in the south-central Swedish Svecofennian. The first paper is based on whole-rock geochemistry to show the plate tectonic setting of volcanic rocks within the HG. LÄS MER