Sökning: "Vulkanism"

Visar resultat 6 - 9 av 9 avhandlingar innehållade ordet Vulkanism.

  1. 6. Studies of Volcanic Influence on Aerosols, Clouds and Climate

    Författare :Johan Friberg; Ergonomi och aerosolteknologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lowermost stratosphere; volcanic aerosol; upper troposphere; sulfurous aerosol; carbonaceous aerosol; ion beam analysis; volcanism; indirect effect; radiative forcing; direct effect; Stratosphere; Fysicumarkivet A:2016:Friberg;

    Sammanfattning : This thesis focuses on the influence of volcanism on the compositions of the aerosols in the upper troposphere (UT) and lowermost stratosphere (LMS), and their direct and indirect impact on climate. Aerosol data were obtained by aircraft-borne sampling, using the CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container) platform, and laboratory-based ion beam analysis of aerosol samples at the Lund Ion Beam Analysis Facility (LIBAF). LÄS MER

  3. 7. Geochemical and sedimentary signatures of Phanerozoic events

    Författare :Jane Wigforss-Lange; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; geokemi; Sedimentology; Petrology; mineralogy; geochemistry; Petrologi; mineralogi; Carbon and oxygen isotopes; Jurassic-Cretaceous boundary; K-T boundary; Late Silurian; Events; Trace elements; Sedimentologi;

    Sammanfattning : Geological and biological catastrophic events have occurred repeatedly in the Earth's history, leaving traces in the global stratigraphical record in the form of sedimentary features, geochemical anomalies and biotic turnovers. This thesis focuses on the sedimentological and geochemical signatures of several key events in the Phanerozoic stratigraphical record, and aims to interpret the different signals and the causal mechanisms behind each of these events. LÄS MER

  4. 8. 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

  5. 9. Conodont biostratigraphy, taxonomy and palaeoecology in the Darriwilian (Middle Ordovician) of Baltoscandia - with focus on meteorite and extraterrestrial chromite-rich strata

    Författare :Johanna Mellgren; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Conodonts; biostratigraphy; taxonomy; palaeoecology; morphometrics; extraterrestrial chromite; meteorites; Darriwilian; Middle Ordovician; Baltoscandia;

    Sammanfattning : This thesis deals with conodont biostratigraphy and palaeoecology in the Darriwilian (Middle Ordovician) of Baltoscandia, with focus on limestone strata showing traces of the ~ 470 Ma L-chondrite parent body break-up. The evidence for this cosmic event includes abundant centimeter to decimeter-sized fossil meteorites and elevated levels of sediment-dispersed extraterrestrial L-type chromite found in a stratigraphical interval corresponding to the uppermost Lenodus antivariabilis, the L. LÄS MER