Sökning: "isotope excursions"
Hittade 4 avhandlingar innehållade orden isotope excursions.
1. Geology, stratigraphy, and fossil vertebrates of Gotland, Sweden : a review
Sammanfattning : The Silurian limestones of Gotland, Sweden, and their exceptionally well-preserved fossils have attracted the interest of scientists for more than 200 years. The sedimentary rocks represent approximately 10 million years of time, and were deposited in a shallow, equatorial inland sea named the Baltic Basin. LÄS MER
2. Studies on Tropical Palaeo-variation in Climate and Cosmic Ray Influx : Geochemical data from stalagmites collected in Tanzania and northern South Africa
Sammanfattning : The main aims of this project were to contribute to the knowledge about tropical climate variations, and to investigate the possibilities of obtaining cosmic ray influx data from stalagmites.Stalagmites from Tanzania and northern South Africa were palaeoclimatologically analysed. LÄS MER
3. Biostratigraphy and Systematics of Cambrian Small Shelly Fossils from East Antarctica and South Australia
Sammanfattning : The remote lower Cambrian Byrd group of sedimentary rocks from East Antarctica has been studied intermittently since its discovery over a century ago. Previous insights into the trilobites and archaeocyaths indicated a close correlation to the sedimentary sequences of South Australia. LÄS MER
4. Geochemical and sedimentary signatures of Phanerozoic events
Sammanfattning : Geological and biological catastrophic events have occurred repeatedly in the Earth's history, leaving traces in the global stratigraphical record in the form of sedimentary features, geochemical anomalies and biotic turnovers. This thesis focuses on the sedimentological and geochemical signatures of several key events in the Phanerozoic stratigraphical record, and aims to interpret the different signals and the causal mechanisms behind each of these events. LÄS MER