Sökning: "tephrochronology"

Visar resultat 1 - 5 av 10 avhandlingar innehållade ordet tephrochronology.

  1. 1. Ashes to ashes : Applications of tephrochronology in Scandinavia

    Författare :Simon A. Larsson; Stefan Wastegård; Britta Sannel; Christine Lane; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tephrochronology; tephrostratigraphy; tephra; palaeoclimate; Last Glacial–Interglacial Transition; Scandinavia; naturgeografi; Physical Geography;

    Sammanfattning : The project presented in this thesis provides two examples of applications of tephrochronology in Scandinavia. The usage of tephra deposits preserved in sediments—i.e. LÄS MER

  3. 2. Tephra horizons in the North Atlantic region during the Early Holocene

    Författare :Ewa Lind; Stefan Wastegård; Margareta Hansson; Britta Sannel; Victoria Smith; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tephrochronology; geochemical composition; Saksunarvatn Ash; Vedde Ash; Fosen Tephra; Askja-S; palaeoclimate; Younger Dryas; Early Holocene; “XRF ITRAX”; sediment geochemistry; stable isotopes; Faroe Islands; Norway; Sweden; kvartärgeologi; Quaternary Geology;

    Sammanfattning : Uncertainties about the rate and magnitude of future climate change have drawn attention to the climate variability following the Late Glacial-Early Holocene transition, c. 12-8 ka BP. LÄS MER

  4. 3. Tree-limit ecotonal response to Holocene climate change in the Scandes Mountains of west-central Sweden

    Författare :Jonas Bergman; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tree-limit ecotone; alpine vegetation; tephrochronology; peat humification; plant macrofossils; Palaeobotany; fylogeni; Paleobotanik; palynology; phylogeny; palynologi; Geologi; Geology; pedology; geomorphology; Physical geography; klimatologi; geomorfologi; climatology; Fysisk geografi; cartography; Holocene climate; palaeoecology; marklära; kartografi; pollen influx;

    Sammanfattning : The aim of this thesis was to reconstruct the Holocene vegetational and climatic development in the Sylarna-Storulvån area, western Jämtland, in the central Scandes Mountains. Temporal trends and fluctuations in the elevation and vegetational character of the tree-limit ecotone were studied mainly by means of pollen and plant macrofossil analysis of two lake sediment sequences (Lakes Stentjärn and Spåime), located above the present-day tree-limit. LÄS MER

  5. 4. Geology of Lagoa das Furnas, a crater lake on São Miguel, Azores archipelago

    Författare :Thommy Andersson; Otto Hermelin; Martin Jakobsson; Alasdair Skelton; Erik Sturkell; Richard Gyllencreutz; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lagoa das Furnas; Azores; crater lake; geophysical mapping; tephrochronology; volcanic dome; Marine Geology; maringeologi;

    Sammanfattning : In this thesis, the results from a geophysical mapping and coring campaign of Lagoa das Furnas are presented. Specific focus is placed on the origin of a subaqueous volcanic cone mapped in the southern part of the lake. LÄS MER

  7. 5. Setting the Holocene clock using varved lake sediments in Sweden

    Författare :Lovisa Zillén; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; climate change; Physical geography; tephrochronology; palaeomagnetic secular variations; radiocarbon time-scale; Holocene varved lake sediments; varve chronology; geomorphology; pedology; cartography; climatology; Fysisk geografi; geomorfologi; marklära; kartografi; klimatologi;

    Sammanfattning : The aim of this thesis was to study annually laminated (varved) Holocene lake sediment in Sweden, their formation and their potential as chronological and palaeoecological archives. Five lakes with continuous Holocene varved lake sediment sequences in northern (Västerbotten) and west central Sweden (Värmland) were investigated. LÄS MER