PhD opportunity: The evidence and implications of Cretaceous Wildfires

Supervisors: Professor Gregory Price; Dr Paul Sutton; Dr Steve Grimes University of Plymouth; Dr Rhodri Jerrett University of Manchester

Project Description

Major perturbations in the Cretaceous global carbon cycle are reflected in long- and short-term fluctuations of δ13C and are commonly associated with the deposition of organic-rich sediments in the world oceans. The first major carbon cycle perturbation of the Cretaceous is within the Valanginian (the Weissert Event). This enigmatic event is proposed to have resulted from an increase in the rate of sedimentary burial of 13C-depleted organic carbon which has been tentatively related to oceanic anoxia. The enhanced burial rate should have led to a drop in the atmospheric pCO2 concentrations and the leak of O2 to the atmosphere. A means to evaluate the significance and potential impact of perturbations in the global carbon cycle and linked changes in atmospheric O2 is to examine the record of wildfires from a range of well-constrained Late Jurassic to Cretaceous marine sections in Europe as well as samples derived from the IODP. Assuming that oxygen is a dominant factor influencing fire during this time, estimates of atmospheric pO2 variability can be derived from wildfire proxies i.e. Polycyclic Aromatic Hydrocarbons and charcoal. Therefore, this project aims to determine trends in Polycyclic Aromatic Hydrocarbons, coupled with charcoal abundance and carbon isotopic analyses, through the latest Jurassic -Early Cretaceous (and across a major carbon cycle perturbation) in a number of key sections providing quantitative data on wildfire activity. As well as using these organic proxies to detect and quantify the wildfire this combined chemostratigraphic and organic-geochemical approach will provide further data regarding characterising the controls on one of the most significant paleoceanographic events of the Early Cretaceous. This research has significant in terms of understanding other Mesozoic events as deep time variation in atmospheric O2 has also played a key role in the evolution of life on Earth.

You will become an expert in cutting-edge techniques to sample and analyse Cretaceous marine sediments conducting geological fieldwork in Spain and France as well as sampling from the IODP core repository. You will receive training in advanced analytical techniques, including stable isotope mass spectrometry, isolation of PAHs from sediment samples and charcoal analysis.

This project will provide a first-class research experience for a student interested in Earth sciences. The scope of the research question will allow independent thinking and hypothesis testing, and result in a significant contribution to knowledge. This project will also allow the student to develop a broader methodological profile as well as develop research that has direct relevance to the petroleum field.

Eligibility

Applicants should have as a minimum a 1st or 2.1 degree in Earth sciences and be enthusiastic about taking an interdisciplinary approach to research. A knowledge of isotope geochemistry is desired. 

If you wish to discuss this project further, please contact  Professor Gregory Price.  

However, applications must be in accordance with the details below.

Funding

The studentship is supported for three years and includes full home/EU tuition fees plus a stipend of £15,009 per annum.  

Applicants normally required to cover overseas fees will have to cover the difference between the home/EU and the overseas tuition fee rates (approximately £12,285 per annum).

How to apply

General information about applying for a research degree at the University of Plymouth.

Please apply via the online application form which can be found at: https://www.plymouth.ac.uk/study/postgraduate and click ‘Apply’.  

Please mark it FAO Nikki King, clearly stating that you are applying for a PhD studentship within the School of Geography, Earth and Environmental Sciences. Please attach a covering letter detailing your suitability for the studentship, a CV, research statement, and 2 academic references. 

The closing date for applications is 12 noon on 31 May 2019. Shortlisted candidates will be invited for interview mid June. We regret that we may not be able to respond to all applications. Applicants who have not received an offer of a place by 30 June 2019 should consider their application has been unsuccessful on this occasion.