Unfortunately, Dr Richard Stockey will not be joining us due to illness. We hope to reschedule his visit ASAP.

Our speaker instead will be Dr Michael Henehan (School of Earth Sciences, University of Bristol). His talk is titled: Carbon Cycling at the Dawn of the Cenozoic.

Michael is a relatively new addition to the school, so please do come along and learn more about his exciting research. Refreshments will be provided!

While we look forward to seeing you all in-person in G27, the seminar will also be available via Zoom. However online participants may not be able to engage fully in live discussion or Q&A.

Join Zoom Meeting: https://bristol-ac-uk.zoom.us/j/97513672994

Abstract: The Paleocene – the first epoch of the Cenozoic (66–56 Ma) – is an intriguing, and often puzzling, time interval sandwiched between the charismatic events of the Paleocene-Eocene Thermal Maximum (PETM) and Cretaceous-Palaeogene (K-Pg) boundary. The epoch spans numerous notable climatic and biogeochemical phenomena. In the oceans, the Paleocene saw the drawn-out recovery of calcifying plankton communities after severe extinction caused by the K-Pg impact, followed by one of the largest excursions in benthic marine carbonate δ¹³C values of the last 100 Myr in the form of the Paleocene Carbon Isotope Maximum. On land, an as-yet-unexplained extreme step-change in global weathering regime is indicated by marine carbonate δ⁷Li values. More generally, despite benthic foraminiferal oxygen isotopes that suggest a greenhouse climate much warmer than today, scant proxy estimates of atmospheric CO₂ in the Paleocene mostly indicate low levels more like those seen during the relatively colder late Neogene.

In this talk, Michael will summarise some of the recent headway we have made in understanding geochemical cycling and ocean chemistry at the dawn of the Cenozoic, immediately after the K-Pg impact. Following this, new benthic and planktic foraminiferal boron and lithium isotope data will be presented that address some of the outstanding puzzles of this formative period for the Cenozoic carbon cycle. Our new, higher boron-derived atmospheric CO₂ estimates for this interval resolve some of the apparently anomalous behaviour of the Paleocene climate system, and in doing so provide a better understanding of the climatic baseline to the PETM.

At the end of the talk, Michael will introduce future research plans at Bristol - specifically my 5-year ERC Consolidator Grant (now a UKRI Frontier Research Grant) PETRARCH, with the help of which hopes to push some of these quantitative proxy approaches back to the peak warmth of the Cretaceous period. 

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The text for the original talk is below:

We are pleased to welcome Dr Richard Stockey who will be delivering a seminar on: Earth systems palaeobiology - reconstructing the habitats of ancient marine animals through the bad times and the good.

Abstract:

The fossil and geochemical records offer the tantalising opportunity to study the responses of marine ecosystems to environmental change at extended timescales. At face value, this avenue for investigating the impacts of environmental change on Earth’s biosphere is very appealing for addressing questions about both Earth’s long-term habitability and the ecological consequences of climate change. However, although many fruitful insights have been gained by correlating fossil and geochemical data, we are faced with the challenge that geologic records generally provide indirect archives of the living phenomena that many deep time studies are motivated by. As a result, empirical datasets that take immense effort to generate often speak obliquely to the questions that palaeobiologists and Earth historians would most like to answer. Intermediate complexity Earth system and ecological modelling, and statistical approaches, are used to try to confront these issues and bridge the communication gaps between our geological records of environmental and ecological change.

Dr Richard Stockey will discuss recent and ongoing research using Earth system, ecological and statistical modelling to better understand how changing environmental conditions have impacted the inhabitants of Earth’s oceans at long timescales. New insights will be presented into the role of permissive environments in major evolutionary and ecological radiations of marine animals, including the Cambrian radiation and Great Ordovician Biodiversification Event. There will also be discussion of preliminary results from ongoing work using experimental Earth systems modelling to better compare ancient climate change events and their ecological impacts, with the aim of constraining how and when ancient hyperthermals can be useful for understanding scenarios for Earth’s future.

All staff and students welcome