University of Exeter funding: Magmatic to hydrothermal semi-metal

GeoNetZero Centre for Doctoral Training (CDT): Magmatic to hydrothermal semi-metal fluxes in the Caledonides of the British Isles Ref: 3881

About the award

GeoNetZero

The CDT led by Herriot Watt, represents an exciting partnership between the Universities of Aberdeen, Birmingham, Dundee, Durham, Exeter, Keele, Newcastle, Nottingham, Plymouth, Royal Holloway and Strathclyde, the British Geological Survey, the Natural Environment Research Council and the Ministry of Business, Energy & Industrial Strategy. Its bespoke residential training program is funded by 9 industry sponsors: BP, Cairn Energy, Chrysaor, CNOOC, Equinor, ExxonMobil, Shell, Total and Verus Petroleum.

The CDT's research focus is on tackling the challenge of sustainable resource management and the crucial role the subsurface will play in the low-carbon energy transition towards a net zero carbon economy, covering the full spectrum of topics from carbon storage and geothermal energy to sustainable oil and gas resource management. The CDT projects will be of interest to those with a background primarily in the geosciences.

The CDT's academic partners have 17 fully-funded positions PhD available to commence in September 2020.  Studentships are for 4 years, provide funding for tuition fees and stipend at the national UK Research & Innovation (UKRI) level and a generous £5k per annum Research Training & Support Grant (RTSG) allowance.

Location: Camborne School of Mines and the Environment & Sustainability Institute, Penryn, Cornwall.

Primary Supervisor: Dr. Kathryn Moore, Senior Lecturer in Critical and Green Technology Metals, k.moore@exeter.ac.uk

Project Description:

This project interrogates the relative roles of disparate sources and processes in the concentration of potential by- or co-product critical metals, vital for many green energy technologies. The semi-metals tellurium (Te) and selenium (Se) are largely recovered during electrolytic refining of copper but they also contribute to the economic potential of gold and silver deposits. Some mesothermal and epithermal Au-Te deposits have ore fluids and Te sourced from the mantle. The Te distribution in deep soils (open-access Tellus data hosted by the Geological Survey of Ireland) across Northern Ireland broadly correlates with minor intrusions, principally mantle-derived lamprophyres. Controversy surrounds whether gold is mantle-derived and associated with lamprophyric magmas. Lamprophyres are spatially related to gold deposits in the Republic of Ireland and Scotland, are abundant in contiguous terranes hosting gold mineralisation in Northern Ireland, and provide an under-utilised means to interrogate the flux of critical metals from the mantle.

Tellurium2

 

The distribution of tellurium in the Tellus Project S-horizon (deep) soil samples over parts of Northern Ireland (samples with lower concentrations are omitted for clarity) (Lusty, 2016). Note the coincidence of positive Te anomalies on the Downpatrick coastline, which is intruded by lamprophyres.

 

 

 

 

 

 

 

 

 

 

Firstly, this project will use the spatial association of mineralisation and lamprophyres to interrogate mantle influence and the magmatic + magmatic fluid controls on semi-metal enrichment in precious and base metal mineralisation in areas of the Caledonian Terranes of Scotland, Northern Ireland and western Ireland. Investigations of metal and semi-metal fluxes will utilise samples obtained from sites of interest, identified using Tellus (open access) deep soil data.

Secondly, this project will seek to elucidate whether the mantle source is dominant or subordinate to the crustal source. Pilot investigations using the Tellus Northern Ireland data set indicate that the sedimentary succession in the Southern Uplands Terrane has elevated background Te and Se concentrations and possibly represents a geological reservoir for these and related metals. The degree of concentration of critical metals in large basins will be investigated using the Tellus and G-Base data (Southern Uplands, Grampian and Highland Terranes) where alluvial gold is known to have significant Te and Bi content. Northern Ireland is an important case study since it is covered by the highest resolution of geochemical (and geophysical) data.

Critical metal concentrations in sedimentary rocks and lamprophyres, analysed by the student, will inform comparisons of metal fluxes and co-variation in the critical metal budget as a function of geological environment. Ultimately, the project aims to generate a petrogenetic model for the fluxes of semi-metals from the mantle through the crust on the Atlantic margins. Training in utilisation of the Tellus and G-Base data will be based at BGS; analysis and modelling will be based at the University. The core of the project comprises geochemical and numerical modelling.

Project Objectives:

The successful PhD candidate will:

  1. Review the extensive literature on the use of tellurium, arsenic and other metals as path finders for gold deposits; the ultimate sources of gold and fluid pathways; the association between gold and lamprophyres.
  2. Interrogate the occurrence of semi-metals and associated metals in the G-Base data, Tellus NI data, and the more recently released cross-border Tellus data.
  3. Enhance the Tellus data set with published analyses from the literature and target areas around the North Atlantic margins for further investigation.
  4. Obtain further geochemical (bulk rock and mineral) data where appropriate.
  5. Use statistical methods to establish end member compositions for modelling of fluxes.
  6. Use finite element modelling of magmatic injection or fluid flux, into and through sedimentary basins to simulate focussing of semi-metals into mineralising systems.
  7. Discuss the results in terms of the global settings of mineralisation and potential for by-product semi-metal production.

Funding
Studentships are fully funded for 4 years and cover tuition fees and stipend at the UK Research & Innovation recommended levels for each year of study.  For the 2020/21 academic session, this is £4,327 for fees and £15,009 for stipend.

The studentship period is 4 years in order to accommodate the CDT’s bespoke 20-week residential training programme, attendance on which is a condition of acceptance of a funded CDT studentship.

Eligibility
Funding of tuition fees is at the UK level which currently also applies to EU students but this may change in respect of the later years of study depending on the outcome of Brexit negotiations and the stance adopted by each participating CDT university.  EU and International students are therefore advised to contact the hosting university to check whether additional funding is available to cover the potential difference in fee levels charged to Home and International students before submitting an application.


Visit the GeoNETZero CDT website for information about the partnership or contact the CDT manager, Lorna Morrow, on L.H.Morrow@hw.ac.uk

Entry requirements

Applicants for this studentship must have obtained, or be about to obtain, a First or Upper Second Class UK Honours degree, or the equivalent qualifications gained outside the UK, in an appropriate area of science or technology.

If English is not your first language you will need to have achieved at least 6.0 in IELTS and no less than 6.0 in any section by the start of the project.  Alternative tests may be acceptable see /http://www.exeter.ac.uk/pg-research/apply/english/

How to apply

In the application process you will be asked to upload several documents.  Please note our preferred format is PDF, each file named with your surname and the name of the document, eg. “Smith – CV.pdf”, “Smith – Cover Letter.pdf”, “Smith – Transcript.pdf”.

  • CV
  • Cover Letter (outlining your academic interests, prior research experience and reasons for wishing to undertake the project)
  • Research proposal
  • Transcript(s) giving full details of subjects studied and grades/marks obtained (this should be an interim transcript if you are still studying)
  • Two references from referees familiar with your academic work. If your referees prefer, they can email the reference direct to stemm-pgr-admissions@exeter.ac.uk quoting the studentship reference number 3881
  • If you are not a national of a majority English-speaking country you will need to submit evidence of your proficiency in English

The closing date for applications is midnight on 31st March 2020.  Interviews are likely to be held between 29 and 30 April 2020.

If you have any general enquiries about the application process please stemm-pgr-admissions@exeter.ac.uk

Project-specific queries should be directed to the main supervisor.

Please quote reference 3881 on your application and in any correspondence about this studentship.

 

Summary

Application deadline:31st March 2020
Number of awards:1
Value:4-year studentship: Tuition fees (UK/EU) and an annual stipend at the national UKRI level
Duration of award:per year
Contact: Postgraduate Admissions Office stemm-pgr-admissions@exeter.ac.uk