Sökning: "Kvartärgeologi"

Visar resultat 1 - 5 av 153 avhandlingar innehållade ordet Kvartärgeologi.

  1. 1. Dansgaard-Oeschger cycles and Heinrich events in western Europe - A diatom perspective

    Författare :Linda Ampel; Barbara Wohlfarth; Jan Risberg; Sherilyn Fritz; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Dansgaard-Oescher cycles; Heinrich events; MIS 3 and 2; diatoms; Les Echets; France; Quaternary geology; Kvartärgeologi; Quarternary Geology; kvartärgeologi;

    Sammanfattning : The last glacial period was characterised by several abrupt climatic shifts referred to as Dansgaard-Oeschger (DO) cycles and Heinrich events. These shifts were most frequent between 60,000 and 20,000 years before present coinciding with Marine Isotope Stages (MIS) 3 and 2. LÄS MER

  2. 2. Late Holocene humidity variability in central Sweden

    Författare :Sofia Andersson; Stefan Wastegård; Gunhild Rosqvist; Kristian Schoning; Frank Chambers; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; humidity change; stable isotopes; Chara spp; Pisidium spp; testate amoebae assemblages; humification; C N ratio; late Holocene; central Sweden; Quaternary geology; Kvartärgeologi; Quarternary Geology; kvartärgeologi;

    Sammanfattning : The aim of this thesis was to reconstruct humidity variability in central Sweden during the late Holocene. A multi-proxy approach was used to infer humidity changes as recorded in a lake and a mire. Age-models were constructed based on radiocarbon dating and the Askja-1875 tephra. LÄS MER

  3. 3. Late Quaternary ice sheet history and dynamics in central and southern Scandinavia

    Författare :Timothy Johnsen; Helena Alexanderson; James T. Teller; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Scandinavian ice sheet; ice sheet dynamics; luminescence dating; cosmogenic exposure dating; geochronology; moraine; interstadial; deglaciation; nunatak; Quaternary geology; Kvartärgeologi; Quarternary Geology; kvartärgeologi;

    Sammanfattning : Recent work suggests an emerging new paradigm for the Scandinavian ice sheet (SIS); one of a dynamically fluctuating ice sheet. This doctoral research project explicitly examines the history and dynamics of the SIS at four sites within Sweden and Norway, and provides results covering different time periods of glacial history. LÄS MER

  4. 4. Holocene climate change in high latitudes recorded by stable isotopes in peat

    Författare :Päivi Kaislahti Tillman; Steffen Holzkämper; Stefan Wastegård; Peter Kuhry; Mats Rundgren; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; -; Quaternary geology; Kvartärgeologi; Quarternary Geology; kvartärgeologi;

    Sammanfattning : A key to the understanding of natural and human induced climate variations is to reconstruct past changes from different environments. No outstanding method for general use has been pinpointed, instead, a need of multi-proxy studies is often stressed and the reconstructions are under constant improvement by new techniques. LÄS MER

  5. 5. Terrestrial response to Dansgaard-Oeschger cycles and Heinrich events : the lacustrine record of Les Echets, south-eastern France

    Författare :Daniel S. Veres; Barbara Wohlfarth; John J. Lowe; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; lake sediments; palaeoclimate; organic matter; Dansgaard-Oeschger cycles; Heinrich events; MIS 3; Western Europe; Quaternary geology; Kvartärgeologi; Quarternary Geology; kvartärgeologi;

    Sammanfattning : Marine Isotope Stage (MIS) 3 was an interval characterized by large and abrupt temperature changes on a millennial time scale, the so-called Dansgaard-Oeschger (DO) cycles and Heinrich events. Evidence for this high-frequency climate variability has been identified in many marine and ice core records. LÄS MER