University of Hong Kong Featured PhD Programmes
Birkbeck, University of London Featured PhD Programmes
University of East Anglia Featured PhD Programmes

About the Project

Mars atmospheric evolution was marked by an early, dense CO2-rich atmosphere giving sufficient greenhouse warming to enable liquid water at the surface, followed by atmospheric loss leaving a less dense atmosphere with cold, arid surface conditions. The timing of atmosphere loss is not known, but may have coincided with a period of heavy meteorite bombardment ~4 billion years ago. Noble gases offer key insight into the processes controlling the atmosphere systems on terrestrial planets. Because they are inert, the behaviour of noble gases in planetary reservoirs is controlled by relatively simple physical processes. As volatile elements, they are strongly depleted leading to significant modification of their primary isotope ratios (i.e. acquired at the time of accretion) by radioactive decay of isotopes of other elements. Where this occurs, the range of half lives provided by the precursors 129I (decaying to 129Xe in 16 Ma), 244Pu fission (131-136Xe, 80 Ma), 40K (40Ar, 1.3 Ga), 238U fission (131-136Xe, 4.5 Ga) provide distinct time constraints on models of atmosphere evolution.

Martian meteorites are our only samples from Mars and are mostly relatively young (≤1.3 Ga) igneous rocks that are considered to be largely unrepresentative of the martian surface. However, in 2013, the first martian meteorite identified as a regolith breccia from the martian surface was described. As a breccia, this meteorite contains a diverse array of lithic components that crystallised by ~4.4 Ga punctuated by impact-driven resetting events all the way to 170 Ma. Martian atmospheric gases trapped within different lithic clast components could potentially provide a unique record of the early martian atmosphere.

The aim of this project is to determine the noble gas isotopic composition of the martian atmosphere through time. A major focus will be on noble gases in clast components of the matain regolith breccia meteorite North West Africa (NWA) 8114. A clast-by-clast approach will be used in an attempt to piece together the evolution of the martian atmsophere over time. If ancient and modern noble gas components in NWA 8114 can be resolved it will provide insight into the source of accretionary volatiles (e.g. solar, cometary), the timing and extent of atmospheric loss, and the rate of atmospheric replenishment by degassing of the martian mantle. To provide context and additional insights, results from NWA 8114 will be supported by analyses of other selected martian meteorites, including the younger shergottites which retain a noble gas signature representative of the modern martian atmosphere, and nahklites which show evidence for a more ancient atmospheric noble gas composition.

Samples will be characterised using optical and electron microscopy techniques, and mineral chemistry by electron microprobe. Noble gas isotopes will be analysed in individual components (clasts, mineral separates, shock glass) using noble gas mass spectrometry.

Suggested skills needed. The project would suit a student interested in planetary evolution, Mars science and geochemistry. This is a laboratory-focussed project so good practical skills and a willingness to learn and apply analytical techniques is essential. A background in geoscience, physics or chemistry at undergraduate level is desirable.

Application process:

• Read the information on the DEES webpage https://www.ees.manchester.ac.uk/study/postgraduate-research/doctoral-training/planetary-science/ to ensure that you understand the funding eligibility requirements for the award.
• Contact the supervisors to discuss your interest in the project – this is an essential step so that you can ask questions and find out more about the supervisory team before you apply.
• Your application must be made online at https://www.ees.manchester.ac.uk/study/postgraduate-research/how-to-apply/.
• The applications received will be reviewed by the project supervisory team and they will put forward their preferred candidates for a panel review process. An STFC DTP academic panel will then review all the nominated students and decide who to shortlist for an interview. An interview will take place so that the panel can meet the short-listed candidates and decide who to offer the studentship to. The interview normally is about 20-30 minutes and on the interview day you will have a chance to visit the department and group research facilities and meet with our current STFC stduents and staff. Candidates are normally informed within a few days of the interview if they have been offered a studentship.

Please contact Ray Burgess () if you are interested and wish to find out further information.

Funding Notes

This is a 3.5 year STFC-funded studentship.

Funding eligibility
Please see the link below for more information about funding eligibility:
View Website

We particularly welcome applications from students from under-represented groups.

References

Agee C. B., et al. (2013) Science, 339, 780–785.
Cartwright J.A. et al (2014) Earth and Planetary Science Letters 400, 77-87
MacArthur J.L. et al (2019) Geochimica Cosmochimica Acta 246, 267-298.
Ott U. et al (2019) Volatiles in the Martian Crust, Chapter 3, 35-70.

Email Now

Insert previous message below for editing? 
You haven’t included a message. Providing a specific message means universities will take your enquiry more seriously and helps them provide the information you need.
Why not add a message here

The information you submit to The University of Manchester will only be used by them or their data partners to deal with your enquiry, according to their privacy notice. For more information on how we use and store your data, please read our privacy statement.

* required field

Your enquiry has been emailed successfully



Search Suggestions

Search Suggestions

Based on your current searches we recommend the following search filters.



FindAPhD. Copyright 2005-2020
All rights reserved.