Sökning: "palaeomagnetic secular variation"

Hittade 4 avhandlingar innehållade orden palaeomagnetic secular variation.

1. 1. Testing palaeomagnetic and 14C based geochronological methods in the Baltic Sea

   Författare :Bryan Lougheed; Kvartärgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; coastal; geochronology; palaeomagnetic secular variation; PSV; radiocarbon; 14C; reservoir age; R t ; ΔR; salinity; δ18O; geomagnetic field; Holocene; deglacial; Fennoscandia.;

   Sammanfattning : The Baltic Sea is a continental shelf sea that is influenced by both river runoff and marine water. The two water masses are vertically stratified in the Baltic Sea, resulting in a positive, estuarine circulation system, which has undergone changes in the past due to isostatic uplift of the Baltic basin. LÄS MER

3. 2. Pollen analysis, chronology and palaeomagnetism of three Late Weichselian sites in southern Sweden

   Författare :Jonas Ising; Kvartärgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; southern Sweden; calendar year chronology; Late Weichselian; Pollen stratigraphy; palaeomagnetic secular variations; Geology; physical geography; Geologi; fysisk geografi;

   Sammanfattning : Three sites, Torreberga in Skåne, Farslycke in Blekinge and Lake Bolmen in Småland, with Late Weichselian lake sediments were studied with respect to pollen analysis and palaeomagnetism. The chronologies are based on pollen stratigraphical correlations, radiocarbon dating and, for two of the sites, on a clay-varve chronology. LÄS MER

4. 3. 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

5. 4. Investigations of temporal changes in climate and the geomagnetic field via high-resolution radiocarbon dating

   Författare :Anette Mellström; Kvartärgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; wiggle-matching; Radiocarbon dating; 14C; 2800 cal BP; climate change; solar activity; palaeomagnetism; lake sediments; varves; post-depositional remanent magnetisation; PDRM; lock-in; peat deposits; Sweden;

   Sammanfattning : Geological archives have shown periods of abrupt climate change in the relatively stable Holocene epoch (last ca. 11 700 years). One of these periods was around 2800 cal BP. Several records, mainly from Europe, reveal a shift towards wetter, cooler and windier conditions. LÄS MER