Hydrothermal inputs to global geochemical cycles: a novel high resolution approach to quantifying hydrothermal exchange

(HARRIS_P22ARIES)

Hydrothermal inputs to global geochemical cycles: a novel high resolution approach to quantifying hydrothermal exchange

(HARRIS_P22ARIES)

Project Description

Supervisors

Dr Michelle Harris (School of Geography, Earth and Environmental Sciences, University of Plymouth) – Contact me

Professor Antony Morris (SoGEES, University of Plymouth)

Dr Rebecca Greenberger (California Institute of Technology)

 

Project Background

Global geochemical cycles are fundamental to the Earth system; where, when, and how much elements are cycled through the Earth underpins a broad range of science, including our understanding of ocean chemistry and how the oceans will be impacted by future climate change. Geochemical fluxes from deep sea hydrothermal systems, where seawater circulates through the seafloor and exits back into oceans via hydrothermal vents, are a key component of global geochemical cycles. The ocean crust preserves this fluid/rock interaction (“hydrothermal alteration”) and by analysing these crustal rocks we can estimate the hydrothermal geochemical flux. However, such studies are limited by poor core recovery by scientific ocean drilling and the time-limitations of mineralogical and geochemical studies.

To advance our understanding of hydrothermal budgets, we need higher resolution characterisation of the distribution and composition of hydrothermal alteration throughout the ocean crust. To achieve this, micro-imaging infrared spectroscopy datasets can be collected on recovered drill core, where mineral specific spectral fingerprints can identify the minerals present at sub-mm resolution. This novel project aims to redefine our geochemical budgets by using preserved hydrothermal alteration sampled by drill cores from the Oman Drilling Project and from the International Ocean Discovery Program to calculate geologically robust estimates of hydrothermal geochemical fluxes.

Research methodology

The individual will (1) use micro-imaging spectroscopy datasets to define a set of hydrothermal alteration types in the drill-cores and interpret their abundance and distribution; (2) use representative samples of the different alteration types to characterise the geochemical (major and trace elements and isotopic compositions) variability, and (3) integrate the abundance of alteration types with their geochemical variability to calculate geologically robust geochemical fluxes.

Training

The individual will develop a range of industry and academia relevant skills, with specialist training in micro-imaging spectroscopy and a range of analytical geochemistry (including XRF, ICP-MS and isotopic analysis). The successful candidate will join an international team of researchers including the broader Oman Drilling Project Science team and the ocean drilling community.

Person specification

This PhD is suitable for individuals with degrees in Geology/Earth Sciences with interests in petrology, geochemistry and big-picture Earth Science questions.

References

  • 1) Greenberger, RN., Harris, M., Ehlmann, BE., Crotteau, M., Kelemen, PB., Manning, CE., Teagle, DAH., and the Oman Drilling Project Science Team (inc. Antony Morris) (2021) Hydrothermal Alteration of the Ocean Crust and Patterns in Mineralization with Depth as Measured by Micro-Imaging Infrared Spectroscopy. JGR Solid Earth. doi.org/10.1029/2021JB021976
  • 2) Harris M, Coggon RM, Wood M, Smith-Duque CE, Henstock TJ, Teagle DAH (2017) Hydrothermal cooling of the ocean crust: Insights from ODP Hole 1256D. Earth and Planetary Science Letters, 462:110–121. https://doi.org/10.1016/j.epsl.2017.01.010
  • 3) Vance D, Teagle DAH, Foster GL (2009) Variable Quaternary chemical weathering fluxes and imbalances in marine geochemical budgets. Nature, 458(7237):493–496. https://doi.org/10.1038/nature07828
  • 4) Coggon RM, Teagle DAH, Harris M, Davidson GJ, Alt JC, Brewer TS (2016) Hydrothermal contributions to global biogeochemical cycles: Insights from the Macquarie Island ophiolite. Lithos, 264:329–347. https://doi.org/10.1016/j.lithos.2016.08.024
  • 5) Greenberger RN, Mustard JF, Ehlmann BL, Blaney DL, Cloutis EA, Wilson JH, Green RO, Fraeman AA (2015) Imaging spectroscopy of geological samples and outcrops: Novel insights from microns to meters. GSA Today, 25(12):4–10. https://doi.org/10.1130/GSATG252A.1

Key Information

  • This project has been shortlisted for funding by the ARIES NERC DTP and will start on 1st October 2022. The closing date for applications is 23:59 on 12th January 2022.
  • Successful candidates who meet UKRI’s eligibility criteria will be awarded a NERC studentship, which covers fees, stipend (£15,609 p.a. for 2021-22) and research funding. International applicants (EU and non-EU) are eligible for fully-funded UKRI studentships. Please note ARIES funding does not cover visa costs (including immigration health surcharge) or other additional costs associated with relocation to the UK.
  • ARIES students benefit from bespoke graduate training and ARIES provides £2,500 to every student for access to external training, travel and conferences. 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 in the subject area.
  • 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, visa requirements notwithstanding
  • For further information, please contact the supervisor. To apply for this Studentship click on the “Apply now” link below.
  • 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.

Applications are open

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