Sökning: "magma evolution"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden magma evolution.

  1. 1. Characterising volcanic magma plumbing systems : A tool to improve eruption forecasting at hazardous volcanoes

    Författare :David A. Budd; Valentin Troll; Tod Waight; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; magma plumbing; oxygen isotopes; thermobarometry; crustal assimilation; Katla; Merapi; Kelud; Toba; volcanic hazards; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : This thesis attempts to develop our understanding of volcanic magma plumbing systems and the magmatic processes that operate within them, such as fractional crystallisation, crustal partial melting, assimilation, and magma mixing. I utilise petrology, rock and mineral geochemistry, and isotope systematics to seek to improve our ability to forecast the eruptive frequency and style of active volcanoes, an aspect often lacking in current volcano monitoring efforts. LÄS MER

  2. 2. Geochemical Development of Proterozoic Granites in the SW Baltic Shield

    Författare :Kirsten Holme; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; principal component analysis; granite classification; magma evolution; magma genesis; granite; Eastern Segment; Western Segment; Southwestern Swedish Gneiss Complex; Sweden; Sveconorwegian Orogen; Petrology; mineralogy; geochemistry; Petrologi; mineralogi; geokemi; Geology; physical geography; Geologi; fysisk geografi;

    Sammanfattning : The plutonic rocks in the Western Segment of the Southwestern Swedish Gneiss Complex show a distinct geochemical evolution. The 1.6 Ga Åmål granitoids and Slottsbron migmatites are a quartz dioritic to granodioritic, calc-alkaline rock suite with smooth, but somewhat fractionated, REE and other trace-element patterns. LÄS MER

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

    Författare :Frances M Deegan; Valentin R Troll; Luigi Dallai; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; 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

  4. 4. Silicic Magma Genesis in Basalt-dominated Oceanic Settings : Examples from Iceland and the Canary Islands

    Författare :Sylvia E. Berg; Valentin Troll; Steffi Burchardt; Frances Deegan; Morten Riishuus; Nicholas Arndt; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Silicic magmatism; Iceland; magma-crust interaction; proto-continental crust; early Earth; zircon geochronology and geochemistry; oxygen isotopes; 2011-2012 El Hierro eruption; crustal xenoliths; 3D X-ray μ-CT; volatiles; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : The origin of silicic magma in basalt-dominated oceanic settings is fundamental to our understanding of magmatic processes and formation of the earliest continental crust. Particularly significant is magma-crust interaction that can modify the composition of magma and the dynamics of volcanism. LÄS MER

  5. 5. Trans-crustal magma storage in contrasting tectonic settings

    Författare :Harri Geiger; Frances Deegan; Valentin R. Troll; Katharine Cashman; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; magma plumbing systems; thermobarometry; oxygen isotope analysis; shallow arc storage systems;

    Sammanfattning : Magmatic plumbing systems comprise magma chambers, sheet intrusions, and conduits which link the Earth’s deep interior with the Earth’s surface. As such, they are the structural framework of magma transport and storage that is governed by complex physical and chemical processes in magma reservoirs and through the interaction of magma bodies with surrounding crustal rocks over timescales from hours to millions of years. LÄS MER