Building the oceans: the anatomy of magma flow in sheeted dykes at fast-spreading ridges

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To apply please use the online application form. Simply search for PhD Geological Sciences (and select the entry point of October 2023), then clearly state that you are applying for a PhD studentship and name the project at the top of your personal statement.

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Director of Studies: Professor Tony Morris
2nd Supervisor: Dr Michelle Harris
3rd Supervisor: Dr Andy Parsons
4th Supervisor: Professor Chris MacLeod (macleod@cardiff.ac.uk), School of Earth and Environmental Sciences, Cardiff University 
Applications are invited for a 3.5 years PhD studentship. The studentship will start on 01 October 2023.

Project description
Fast-spreading rate ocean ridges are responsible for forming 50% of the world’s oceans, yet the magmatic processes involved in building the crust remain poorly understood. Transportation of melt at these ridges is typically considered as a 2D process, yet lateral variations in seafloor morphology and erupted lava compositions along ridge axes show that there must also be significant along-axis (3D) transport and evolution of melt during formation of the crust. This project aims to discover how this 3D magma transport system operates in upper crustal sheeted dyke complexes along fast-spreading ridges, using field and laboratory analyses of rocks exposed in the Oman ophiolite, a major slice of oceanic crust and mantle exposed on land, representing the only place in the world where this problem may be addressed.
The student will collect samples from sheeted dykes exposed along a >100 km fossil spreading ridge segment in Oman. In Plymouth, they will perform magnetic fabric analyses on these samples to detect imbrication of crystals along dyke margins, use these microfabrics to determine the 3D orientation of magma flow during dyke intrusion, and map out domains of different dyke emplacement directions along the ridge. They will also determine dyke geochemical compositions and relate these to flow regimes. Paleomagnetic analyses will allow the student to correct dyke orientations and flow directions for the effects of later tectonic rotations, thereby reconstructing the Oman spreading ridge system. 
The student will be trained in: (i) advanced geological fieldwork techniques (including field description and structural analysis of mafic rocks) during two field seasons in Oman; and (ii) a range of magnetic and geochemical techniques that also have wide applications outside of the specific topic of this project. The project links to a wider NERC-funded investigation of the 3D anatomy of magma transport along fast-spreading ridges, allowing the student to become skilled in collaborative research practices via membership of an interdisciplinary research team addressing a major topic in marine geoscience.
Person specification
We are looking for an enthusiastic individual with an Earth Science-related degree, and a passion for fieldwork, geophysics, igneous petrology and structural geology.
Funding notes
This project has been shortlisted for funding by the ARIES NERC DTP and will start on 1 October 2023.
Successful candidates who meet UKRI’s eligibility criteria will be awarded a NERC studentship for 3.5 years, covering fees, stipend (£17,668 p.a. for 2022-23 rate) and research funding. International applicants (EU and non-EU) are eligible for fully-funded UKRI studentships.
ARIES students benefit from bespoke graduate training and £2,500 for external training, travel and conferences.
ARIES is committed to equality, diversity, widening participation and inclusion. Academic qualifications are considered alongside non-academic experience. Our recruitment process considers potential with the same weighting as past experience.
For information and full eligibility visit https://www.aries-dtp.ac.uk/.
Apply
Please clearly state the name of the studentship project code MORRIS_P23ARIES that you are applying for on your personal statement.
If you wish to discuss this project further informally, please contact Professor Tony Morris.
Please see our 'how to apply for a research degree' page for a list of supporting documents to upload with your application.
For more information on the admissions process generally, please contact research.degree.admissions@plymouth.ac.uk.
The closing date for applications is 23:59 (UK Time) 11 January 2023. 

References

1Morris, A., Meyer, M., Anderson, M. W. and MacLeod, C. J., 2019. What dovariable magnetic fabrics in gabbros of the Oman ophiolite reveal about lowercrustal magmatism at fast spreading ridges? Geology, 47, 275-278, doi:10.1130/G45442.1.

2Morris, A., Meyer, M., Anderson, M. W. and MacLeod, C. J., 2016. Clockwiserotation of the entire Oman ophiolite occurred in a suprasubduction zonesetting. Geology, 44, 1055-1058, doi:10.1130/G38380.

3Morris, A. and Maffione, M., 2016. Isthe Troodos ophiolite (Cyprus) a complete, transform fault-bounded Neotethyanridge segment? Geology, 44, 199-202, doi: 10.1130/G37529.1.

4Kelemen, P. B., Matter, J. M., Teagle, D. A. H. Coggon, J. A., and the OmanDrilling Project Science Team (inc. Morris, A., Harris, M., and MacLeod, C. J.), 2020. Proceedings of theOman Drilling Project: College Station, TX (International Ocean DiscoveryProgram), doi: 10.14379/OmanDP.proc.2020.

5 Maffione, M., van Hinsbergen, D. J. J., de Gelder,G. I. N. O., van der Goes, C. and Morris, A., 2017. Kinematics of LateCretaceous subduction initiation in the Neo-Tethys Ocean reconstructed fromophiolites of Turkey, Cyprus and Syria. Journal of Geophysical Research, 122,3953-3976, doi: 10.1002/2016JB013821.