Sökning: "Petrology"

Visar resultat 11 - 15 av 66 avhandlingar innehållade ordet Petrology.

  1. 11. 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

  3. 12. Thermal history of the Phanerozoic sedimentary succession of Skåne, southern Sweden, and implications for applied geology

    Författare :Ingela Olsson; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mineralogy; geochemistry; Petrologi; mineralogi; geokemi; Petrology; organic matter reflectance; organic geochemistry; illite crystallinity; clay mineralogy; thermal history; Phanerozoicum; Skåne; Sweden;

    Sammanfattning : Post-depositional thermal conditions have been investigated throughout the Phanerozoic sedimentary succession in Skåne. Clay mineralogy and illite crystallinity have been the main tools for the Lower Palaeozoic strata. Within the Mesozoic sequence thermal influence was examined using RockEval pyrolysis and vitrinite reflectance analysis. LÄS MER

  4. 13. Understanding Zircon Geochronology - Constraints from Imaging and Trace Elements

    Författare :Andrius Rimsa; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hydrothermal; Petrology; mineralogy; hydraulic fracturing; Sveconorwegian; incipient charnockite; EBSD; cathodoluminescence; REE; Zircon; U-Pb geochronology; geochemistry; Petrologi; mineralogi; geokemi; Kerala Khondalite Belt;

    Sammanfattning : Formation of incipient charnockite in Söndrum, SW Sweden and the Kerala Khondalite Belt (KKB), S. India is accompanied by zircon growth. The age of the dehydration event is constrained by dating newly formed zircon to 1397±4 Ma (2?, MSWD=1.7) in Söndrum and ca. LÄS MER

  5. 14. Constraining the Southern Part of the Greenland Ice Sheet since the Last Glacial Maximum from Relative Sea-Level Changes, Cosmogenic Dates and Glacial-Isostatic Adjustment Models

    Författare :Charlotte Sparrenbom; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; physical oceanography; geokemi; Sedimentology; Sedimentologi; Geophysics; meteorology; mineralogi; geochemistry; mineralogy; Petrology; Geologi; fysisk geografi; physical geography; Geology; neo-glacial; in-situ cosmigenic nuclide; XRF-scanning; glacial-isostatic adjustment models; glacial history; sea-level changes; Greenland; isolation basins; fysisk oceanografi; Petrologi; meteorologi; Geofysik;

    Sammanfattning : New results are presented from the investigation of relative sea-level changes in the Nanortalik and Qaqortoq-Narsarsuaq areas in SW Greenland from c. 11 000 cal. years BP to the present. LÄS MER

  7. 15. Experimental, petrological and geochemical investigations of ikaite (CaCO3·6H2O) formation in marine environments

    Författare :Elin Tollefsen; Alasdair Skelton; Carl-Magnus Mörth; Erik Sturkell; Andrew Putnis; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ikaite; petrology; experiment; geochemistry; marine environments; pseudomorphs; calcium carbonate; Ikka Fjord; glendonite; nepheline; siderite; paleotemperature; carbonatite; Geology; geologi;

    Sammanfattning : Carbonates are a group of minerals that play an essential role in several processes on planet Earth, for example in the global carbon cycle and as a product of biomineralisation. Calcite (CaCO3) is by far the most common mineral in the carbonate group, and the stable form of carbonate at Earth surface conditions. LÄS MER