Sökning: "Ordovician"

Visar resultat 1 - 5 av 38 avhandlingar innehållade ordet Ordovician.

  1. 1. Cambro-Ordovician microorganisms: acritarchs and endoliths

    Författare :Martin Stockfors; Malgorzata Vidal-Moczydlowska; John S. Peel; Kenneth John Dorning; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Earth sciences; Cambrian; Ordovician; acritarch; endolith; Kolguev Island; North Greenland; Stratigraphy; Geovetenskap; Earth sciences; Geovetenskap;

    Sammanfattning : Organic-walled microfossils are abundant and taxonomically diverse in Cambrian-Ordovician strata; some are important for biostratigraphy and for the correlation of geological successions. New assemblages of Cambrian-Ordovician acritarchs from Kolguev Island, Arctic Russia and Middle Cambrian ichnofossils of endoliths from Peary Land, North Greenland are studied. LÄS MER

  2. 2. Early–Middle Ordovician biotic and sedimentary dynamics in the Baltoscandian paleobasin

    Författare :Anders Lindskog; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ordovician; ‘orthoceratite limestone’; carbonate sedimentology; microfacies; paleoecology; paleoenvironment; paleontology; Baltoscandia;

    Sammanfattning : The Baltoscandian region forms part of the paleocontinent Baltica, which was largely covered by a shallow epeiric sea throughout much of the Ordovician (c. 485.5–444 Ma). This ancient sea is today recorded by a thin succession of sedimentary rocks. LÄS MER

  3. 3. Late Ordovician-Early Silurian facies development and stratigraphy of Jämtland, central Sweden

    Författare :Peter Dahlqvist; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; biostratigraphy; Sedimentology; Stratigrafi; Stratigraphy; Paleontologi; Palaeontology; Jämtland; provenance; brachiopods; conodonts; Hirnantian; Silurian; Ordovician; glaciation; eustasy; Sedimentologi; sedimentology;

    Sammanfattning : This thesis is based on studies of Lower Palaeozoic sedimentary successions within the central Scandinavian Caledonides. These deposits have been transported by considerable nappe displacement (several kilometres), and are today relatively isolated from the nearest coeval outcrops (Dalarna 250 km, Oslo Region 350 km). LÄS MER

  4. 4. Middle and Upper Ordovician graptolites, trilobites, and biostratigraphy of Scania and Jämtland, Sweden

    Författare :Christian Pålsson; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; physical geography; Geology; Sweden; Jämtland; Scania Skåne ; Upper Ordovician; Middle Ordovician; palaeoecology; biostratigraphy; lithostratigraphy; Graptolites; trilobites; Geologi; fysisk geografi; Palaeontology; Paleontologi;

    Sammanfattning : Graptolites and some trilobites from Middle–Upper Ordovician siliciclastic and calcareous rocks in Scania (Skåne), southern Sweden, and Jämtland, central Sweden, are described and discussed. Their stratigraphic distribution is discussed on the basis of new and old collections from outcrops and drill cores. LÄS MER

  5. 5. Trilobites from the Middle and Upper Ordovician Andersön Shale Formation in Jämtland and the equivalent Killeröd Formation in Skåne, Sweden

    Författare :Kristina Månsson; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; fysisk geografi; Geologi; physical geography; Geology; Sweden; Jämtland; Skåne; Upper Ordovician; Middle Ordovician; Killeröd Formation; Andersön Shale Formation; ontogeny; biostratigraphy; Trilobita; taxonomy; trilobite associations; Systematic zoology; zoogeography; Zoologisk systematik; djurgeografi; Development biology; growth animal ; embryology; Utvecklingsbiologi; ontogeni; embryologi;

    Sammanfattning : Trilobites from the Middle and Upper Ordovician Andersön Shale Formation in Jämtland, central Sweden, and the Middle Ordovician Killeröd Formation in Skåne (Scania), southern Sweden, are revised and discussed. These formations have several genera and a few species in common, e.g. LÄS MER