Sökning: "acritarchs"
Visar resultat 1 - 5 av 8 uppsatser innehållade ordet acritarchs.
1. Investigation of Thermal Maturity of Organic Matter at the Cambro Ordovician Transition in the Zagros Basin, Iran
Master-uppsats, Uppsala universitet/Institutionen för geovetenskaperSammanfattning : The thermal maturity of sediments from the upper Cambrian to lower Ordovician Mila and Ilbeyk formations in the Zagros Basin in southwestern Iran is evaluated in this thesis. A number of low-cost, fast, optical evaluation methods are utilised to assess their effectiveness for providing accurate, well constrained thermal maturity results. LÄS MER
2. Biodiversity of Organic-Walled Eukaryotic Microfossils from the Tonian Visingsö Group, Sweden
Master-uppsats, Uppsala universitet/Institutionen för geovetenskaperSammanfattning : The diversification of unicellular, auto- and heterotrophic protists and the appearance of multicellular microorganisms is recorded in numerous Tonian age successions worldwide, including the Visingsö Group in southern Sweden. The Tonian Period (1000-720 Ma) was a time of changes in the marine environments with increasing oxygenation and a high input of mineral nutrients from the weathering continental margins to shallow shelves, where marine life thrived. LÄS MER
3. The life cycle and developmental phases of Cambrian-Ordovician organic-walled microfossils from Kolguev Island, Arctic Russia.
Master-uppsats, Uppsala universitet/Institutionen för geovetenskaperSammanfattning : Light microscopy studies of collections of late Cambrian/Early Ordovician organic-walled microfossils, informally called acritarchs, provide the observations on phenotypic traits that are comparable to Modern microalgae and make possible recognition of various developmental stages in their complex life cycle. The exceptionally preserved Saharidia fragilis microfossils show the internal body within the vesicle and the formation of the fringe and pylome, the opening for releasing of the daughter cells from the phycoma-like cyst. LÄS MER
4. A palynological study across the Ordovician Kinnekulle bentonite, Sweden
Kandidat-uppsats, Lunds universitet/Geologiska institutionenSammanfattning : A palynological analysis across the Ordovician (Sandbian) Kinnekulle bentonites in south Central Sweden has been performed. The sedimentary successions were recovered from the Borenshult -1 drillcore in the Motala area, south central Sweden. The lithology is dominated by mudstones and two thick bentonite beds. LÄS MER
5. Sequence stratigraphy, palynology and biostratigraphy across the Ordovician-Silurian boundary in the Röstånga-1 core, southern Sweden
Master-uppsats, Lunds universitet/Geologiska institutionenSammanfattning : A multiproxy study on sedimentary rocks spanning the Ordovician-Silurian boundary has been performed on material from the Röstånga-1 core, with the aims to improve the biostratigraphical and sedimentological framework and to interpret the depositional environment during this interval in Earth’s history. The sedimentary succession in the Röstånga-1 core is developed in the Scanian Lithofacies Belt and is considered an excellent upper Middle Ordovician-Lower Silurian reference section for southernmost Sweden. LÄS MER
