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Visar resultat 1 - 5 av 10 avhandlingar som matchar ovanstående sökkriterier.
1. Late Eocene through Oligocene calcareous nannofossils from the paleo-equatorial Pacific Ocean – taxonomy, preservation history, biochronology and evolution
Sammanfattning : This study aims to unravel the ecological and evolutionary dynamics within the calcareous nannofossil communities at the Eocene/Oligocene (E/O) transition and during the Oligocene time when Cenozoic 'icehouse' conditions were established. The main question this study aims to answer is whether the changes in the nannofossil assemblages were controlled by intrinsic evolutionary trends or if the changes were controlled by environmental factors such as changes in temperature and nutrient availability in the surface water. LÄS MER
2. Mapping bathymetry : From measurement to applications
Sammanfattning : Surface elevation is likely the most fundamental property of our planet. In contrast to land topography, bathymetry, its underwater equivalent, remains uncertain in many parts of the World ocean. Bathymetry is relevant for a wide range of research topics and for a variety of societal needs. LÄS MER
3. Late Quaternary Biostratigraphy and Paleoceanography of the central Arctic Ocean
Sammanfattning : The central Arctic Ocean is one of the least explored deep sea regions and long biostratigraphic sediment records are sparse. The main focus of this thesis is the Arctic Ocean foraminiferal record and its application to reconstruct paleoceanographic variations and summer sea ice cover changes between late Quaternary interglacial periods. LÄS MER
4. Quaternary paleoceanography of the Arctic Ocean : A study of sediment stratigraphy and physical properties
Sammanfattning : A Quaternary perspective on the paleoceanographic evolution of the central Arctic Ocean has been obtained in this PhD thesis by studying sediment cores from all of the Arctic’s major submarine ridges and plateaus. The included cores were mainly recovered during the Healy-Oden Trans-Arctic expedition in 2005 and the Lomonosov Ridge off Greenland expedition in 2007. LÄS MER
5. Organic geochemical investigation of sources, transport and fate of terrestrial organic matter in the southeast Laptev Sea
Sammanfattning : Permafrost carbon stores have been suggested to react to warming trends with increased terrestrial loading to its coastal waters. Presently, the warming has been seen to be especially high in the East Siberian Arctic and the fate of the major release of terrestrial matter to these coasts is yet to be detailed. LÄS MER