From the mantle to the seafloor: How do oceanic core complexes form at mid-ocean ridges?

PARSONS_P25ARIES

From the mantle to the seafloor: How do oceanic core complexes form at mid-ocean ridges?

PARSONS_P25ARIES

Project Description

Supervisors

Dr Andy Parsons, Geography, Earth and Environmental Sciences (SoGEES), University of Plymouth – contact me

Dr Michelle Harris, School of Geography, Earth, and Environmental Sciences, University of Plymouth

Professor Sandra Piazolo, School of Earth and Environmental Sciences, University of Leeds

Dr Jeremy Deans, School of Biological, Environmental, and Earth Sciences, University of Southern Mississippi

 

Project background

At slow-spreading mid-ocean ridges, fault systems known as Oceanic Core Complexes [1] (OCCs) exhume mantle rocks to the seafloor, creating hydrothermal systems that directly impact ocean chemistry, seafloor mineralization, lithospheric rheology, and microbial ecosystems [1-2]. Despite their importance, the formation of OCCs is a poorly understood process which must be constrained to fully understand the how OCCs and mantle exhumation impact our oceans [1-5]. This project will address this fundamental tectonic and marine geoscience problem with a new understanding of how OCCs form.

In 2023, International Ocean Discovery Program (IODP) Expedition 399 collected 1.2km of rock core (U1601C) from the Atlantis Massif OCC on the Mid-Atlantic Ridge [1]. This PhD project investigates the deformation processes that control OCC formation through analyses of U1601C, focusing on the roles of ductile deformation and magmatism as drivers of strain localization during OCC formation [3-4].

Methodology & Training:

–  Microstructural analyses will constrain deformation process recorded in U1601C using state-of-the-art facilities at the Plymouth Electron Microscopy Centre.

–  The candidate will be trained in cutting-edge techniques including Electron Backscatter Diffraction, Wavelength Dispersive Spectroscopy, and Element Mapping to constrain deformation kinematics, temperatures, and extent of magmatic deformation [3-4].

–  The candidate will integrate their microscale analyses with borehole geophysics [5] from Site U1601, using industry-standard software to constrain the km-scale structural evolution of Atlantis Massif.

–  The candidate will test hypotheses and constrain new models for the roles of magmatism and ductile deformation during OCC formation [1, 3-5].

The PhD candidate will develop expertise in electron microscopy, petrophysics, and deformation processes. They will join a world-leading international network of >25 IODP researchers conducting multi-disciplinary research on Atlantis Massif [1], with opportunities to participate in IODP workshops, training, and applications to sail on future IODP expeditions. They will receive support and training to present their work at international conferences and through peer-reviewed publications. These opportunities will provide a strong foundation of transferable skills and expertise for a career in geoscience research.

Person specification

We seek enthusiastic candidates with an Earth Sciences related degree and interests including structural/microstructural geology, plate tectonics/marine geoscience and big-picture Earth Science questions.

Acceptable first degree subjects: Geology, Geophysics, Geology & Geography, Geoscience, Earth Science, or similar.

References

  • Lissenberg CJ, Parsons AJ, et al. (2024). A long section of serpentinized depleted mantle peridotite. Science, 385, 623-629. DOI:10.1126/science.adp1058.
  • Schwarzenbach E, Harris M (2023). Hydrothermal alteration of the oceanic lithosphere. Reference Module in Earth Systems and Environmental Sciences. Elsevier. DOI:10.1016/B978-0-323-99762-1.00016-4
  • Casini L, Maino M, Sanfilippo A, Ildefonse B, Dick HJ (2021). High‐Temperature Strain Localization and the Nucleation of Oceanic Core Complexes (16.5° N, Mid‐Atlantic Ridge). Journal of Geophysical Research: Solid Earth, 126(9), p.e2021JB022215. DOI: 10.1029/2021JB022215
  • Gardner RL, Piazolo S, Daczko NR, Trimby P. (2020). Microstructures reveal multistage melt present strain localisation in mid-ocean gabbros. Lithos, 366, p.105572. DOI: 10.1016/j.lithos.2020.105572
  • Deans JR, Yoshinobu AS (2019). Geographically re-oriented magmatic and metamorphic foliations from ODP Hole 735B Atlantis Bank, Southwest Indian Ridge: Magmatic intrusion and crystal-plastic overprint in the footwall of an oceanic core complex. Journal of Structural Geology, 126, pp.1-10. DOI: 10.1016/j.jsg.2019.05.001

Key Information

  • This studentship has been shortlisted for funding under the UKRI NERC DLA funding scheme and will commence on 1 October 2025. The closing date for applications is 23:59 on 8th January 2025.
  • Successful candidates who meet UKRI’s eligibility criteria will be awarded a fully-funded studentship, which covers fees, maintenance stipend (£19,237 p.a. for 2024/25) and research funding. A limited number of studentships are available for international applicants, with the difference between 'home' and 'international' fees being waived by the registering university. Please note however that ARIES funding does not cover additional costs associated with relocation to, and living in, the UK, such as visa costs or the health surcharge.
  • ARIES postgradute researcher (PGRs) benefit from bespoke graduate training and ARIES provides £2,500 to every student for access to external training, travel and conferences, on top of all Research Costs associated with the project. Excellent applicants from quantitative disciplines with limited experience in environmental sciences may be considered for an additional 3-month stipend to take advanced-level courses.
  • ARIES is committed to equality, diversity, widening participation and inclusion in all areas of its operation. We encourage enquiries and applications from all sections of the community regardless of gender, ethnicity, disability, age, sexual orientation and transgender status. Academic qualifications are considered alongside non-academic experience, and our recruitment process considers potential with the same weighting as past experience.
  • All ARIES studentships may be undertaken on a part-time or full-time basis. International applicants should check whether there are any conditions of visa or imigration permission that preclude part-time study. All advertised project proposals have been developed with consideration of a safe, inclusive, and appropriate research and fieldwork environment with respect to protected characteristics. If you have any concerns please contact us.
  • For further information, please contact the supervisor. To apply for this Studentship follow the instructions at the bottom of the page or click the 'apply now' link.
  • ARIES is required by our funders to collect Equality and Diversity Information from all of our applicants. The information you provide will be used solely for monitoring and statistical purposes; it will remain confidential, and will be stored on the UEA sharepoint server. Data will not be shared with those involved in making decisions on the award of Studentships, and will have no influence on the success of your application. It will only be shared outside of this group in an anonymised and aggregated form. You will be ask to complete the form by the University to which you apply.
  • If funded under the BBSRC-NERC DLA scheme, ARIES studentships will be subject to UKRI terms and conditions. Postgraduate Researchers are expected to live within reasonable distance of their host organisation for the duration of their studentship. See https://www.ukri.org/publications/terms-and-conditions-for-training-funding/ for more information

Apply Now

Apply now via the  University of Plymouth Application Portal