| Summary: | The Paleocene-Eocene Thermal Maximum (PETM) was a global warming event that occurred ~56 Ma and was associated with a negative carbon isotope excursion (CIE). The injection of greenhouse gases during the PETM led to sharp temperature increases and had profound biological effects on both marine and continental ecosystems. The event, with its rapid onset (~3 kyr), is considered one of the best analogues in the geological record for today’s anthropogenic global warming. For this reason, the PETM has attracted the interest of the scientific community with the intent to understand and predict, within limitations, what bioecological changes might occur in the near future. In this thesis, I present new high-resolution isotopic, geochemical, mineralogical and palynological datasets to reconstruct palaeoenvironmental changes around and within the North Sea basin. The North Sea is an important study area due to its proximity to an active Large Igneous Province (LIP) known as the North Atlantic Igneous Province (NAIP). It is believed that the NAIP emplacement led to uplift of the NW section of the North Sea with consequent strong regional basin restriction. One of the aims of the thesis is to discern whether previously observed precursor environmental perturbations were a response to pre PETM climatic change, or were rather driven by local topographic changes. Particular emphasis is on discriminating the causal mechanisms that led to the observed environmental shifts, and consequently to decouple the triggers and drivers of the PETM. The thesis contains geochemical evidence that the North Sea became anoxic and euxinic just before the negative CIE. Bottom water oxygen depletion is commonly associated to climatic responses, such as eutrophication and water column stratification due to atmospheric warming and increased nutrient input during the PETM. Herein I attempt to discern whether anoxia before the CIE was driven by early climatic change or basin restriction. A decoupling of TOC and redox/basin restriction proxies just ...
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