Sökning: "calcareous nannofossils"
Hittade 4 avhandlingar innehållade orden calcareous nannofossils.
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. The emergence of pelagic calcification and its influence on seawater chemistry in the Upper Triassic
Sammanfattning : After the early biomineralisation event in the early Paleozoic (Cambrian –Ordovician; 541 – 443.8 Ma), the Late Triassic (237 – 201.3 Ma) represents another key period of biomineralisation with the onset of the Mesozoic plankton radiation. LÄS MER
3. Eastern equatorial Pacific bulk sediment properties and paleoceanography since the late Neogene
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
4. Origin and the evolution of diatoms through the integration of paleontology and phylogenetics
Sammanfattning : Diatoms, the prominent photosynthetic eucaryotes, have inhabited the world’s oceans for at least the past 120 Ma since their first appearance in the Lower Cretaceous. There are also records of older diatoms, from the Jurassic dating to ca. 172 Ma and ca. 165 Ma, however these are poorly documented. LÄS MER