Sökning: "foraminifera"

Visar resultat 16 - 20 av 21 avhandlingar innehållade ordet foraminifera.

  1. 16. Neoproterozoic-Early Cambrian organic-walled microfossils : Ultrastructural and biogeochemical search for their affinities

    Författare :Nina M. Talyzina; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Geovetenskap; Earth sciences; Geovetenskap; Historical Geology and Paleontology; historisk geologi och paleontologi;

    Sammanfattning : The Neoproterozoic-Cambrian transition is marked by conspicuous radiation of skeletal fauna comparable to modern invertebrates. Phylogenetic relationships of living organisms, based on their genetic and ultrastructural complexity, suggest that most prokaryotic and protistan organisms should have evolved by the time of origination of coelomate organisms. LÄS MER

  3. 17. The Weichselian in southern Sweden and southwestern Baltic Sea : glacial stratigraphy, palaeoenvironments and deglaciation chronology

    Författare :Johanna Anjar; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In this thesis the Weichselian glaciation history of southernmost Sweden and the southwestern Baltic Basin is discussed, with special emphasis on Middle and Late Weichselian ice advances and subsequent deglaciations. The main study area was Kriegers Flak in the southwestern Baltic Sea where pre-Late Weichselian sediments were identified. LÄS MER

  4. 18. Problems of stratigraphic correlation across the Arctic Ocean

    Författare :Emma Sellén; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sedimentology; Sedimentologi;

    Sammanfattning : Published articles on Arctic Ocean sedimentation rates generally falls into two categories; one suggesting mm/ka-scale sedimentation rates in the Amerasian Basin and the other cm/ka-scale rates in the Eurasian Basin. This is due to the interpretation of the first measured paleomagnetic polarity change in sediment cores as either the Brunhes-Matuyama (781 ka) reversal or as the short time magnetic excursion, Biwa II (220 ka) within the Brunhes Chron. LÄS MER

  5. 19. 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

  7. 20. Eastern equatorial Pacific bulk sediment properties and paleoceanography since the late Neogene

    Författare :Daniele Reghellin; Helen K. Coxall; Jan Backman; Gerald R. Dickens; Steve Hovan; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Paleoceanography; late Neogene; eastern equatorial Pacific; deep sea sediments; bulk sediment; stable isotopes; surface mixed layer; sediment physical properties; Marine Geology; maringeologi;

    Sammanfattning : Reconstructing eastern equatorial Pacific (EEP) oceanography since the late Neogene (about 8 million years ago, Ma) is a central topic in current paleoceanographic investigations. The reason for this is two-fold. LÄS MER