From arc magmas to ores (FAMOS): A mineral systems approach

Lead Research Organisation: University of Leicester
Department Name: Sch of Geog, Geol & the Environment

Abstract

Society is dependent on a reliable supply of metals and minerals for economic growth, improved standards of living, and development of infrastructure. Population growth means that even with increased recycling and resource efficiency, new mineral deposits still need to be discovered. The efficient exploration for, and discovery of, new resources requires new concepts and new tools.
The Mineral Systems approach to exploration considers ore deposits on a lithospheric scale, in terms of the "ingredients", processes and environments that favour their formation. This approach amounts to a "source-pathway-trap" model, with an increased emphasis on predictive capacity, rather than just feature recognition. Historically, much research has focused on the trap, and characterisation of the ore deposits themselves; here we aim to focus deeper in the system by integrating ore deposit formation with concepts of magmatism that arise from igneous petrology and volcanology. Therein lies a challenge because extant models for porphyry systems are increasingly at odds with magmatic models for crustal construction and arc volcanism. Rather than seeing magmatic systems in terms of large, liquid-rich magma chambers, emerging petrological models for crustal magmatism are turning instead to crystal-dominated, volatile-bearing "mushy" systems that traverse most or all of the crust. The dynamics of such systems have important consequences not just for arc magmatism, but also for the chemistry of the volatiles that are exsolved. These same volatiles fuel mineralisation and this is the synergy that we aim to exploit by assembling a multidisciplinary team of researchers from economic geology, igneous and metamorphic petrology, volcanology, geochemistry, numerical modelling and fluid dynamics. Our team embraces almost everyone currently engaged in porphyry mineralisation research in the UK and capitalises on strong existing links between UK ROs and the mining industry, many of who are Project Partners.
The research will involve analysis of minerals from a wide variety of mineralised and barren settings using a wealth of modern analytical tools that enable determination of an extensive suite of trace elements and isotope tracers. As each trace element responds to magmatic processes in subtly different ways due to the affinity of different elements for different phases (minerals, melts and fluids), so the multi-element approach affords many advantages over conventional proxies in which the full potential of the Periodic Table is not exploited. The analysis of natural systems will be underpinned by high pressure and temperature experiments to establish the phase relationships of ascending arc magmas and the partition coefficients that capture the affinities of elements for certain phases. As fluid accumulation and migration is an essential, but poorly understood, final step in ore deposit formation, we will develop, in tandem with the geochemistry, numerical models for fluid-bearing mushy systems. Finally, consideration will be given to critical metals that are passengers through the main ore-forming processes, but constitute important, often under-explored, by-products of porphyry mineralisation.
The research proposed has a strong element of blue skies investigation, but a particular focus on outcomes that will benefit industry through improved exploration tools. Thus the project bridges the divide between academic and applied research in a way that is not normally possible through industry-funded projects. This bridging activity lies at the heart of the Highlight Topic call, specifically through the integration of new advances in the study of mineral systems, igneous petrology and geochemistry, with a view to identifying conditions that can act as pathfinders for new targets. A key outcome will be a range of trace element proxies that will enable the mining industry to establish the potential fertility of a magmatic arc on local to regional scales.

Planned Impact

We have taken an "embedded impact" approach with FAMOS. Stakeholders and beneficiaries have been involved with the development of the project from its initiation (including the initial Highlight Topic suggestion). The scientific content of the proposal was developed in discussion with representatives from industry, and the final consortium has assembled an Advisory Board that includes industry representatives so as to maintain two-way knowledge exchange and ensure development of impact. We have also engaged an international set of project partners (PP) who will extend the reach of our impact (see letters of support). The embedded impact will be delivered through various activities to support outreach, engagement and dissemination.

The key impact goal for FAMOS is to improve discovery rates of porphyry deposits by aiding exploration under cover, influencing decision making in the exploration process, reducing exploration risk and reducing the environmental impacts of drilling and associated disruptive fieldwork through more efficient prospectivity assessment.

There are four impact objectives within FAMOS:

1) A revised Mineral Systems model of porphyry deposit formation. This will lead to improved targeting at regional and igneous complex scales and better inputs to national strategies on mineral resources. Beneficiaries include PRIVATE SECTOR COMPANIES involved in mining, exploration and consultancy (e.g. PPs Anglo American, Rio Tinto, BHPBilliton, Freeport McMoRan), and NATIONAL AGENCIES charged with encouraging exploration and developing strategic resources (e.g. BGS and PP USGS).

2) New proxies for porphyry fertility. This will provide low-cost tools and approaches that will support improved decision-making during exploration. By using multiple proxies within a single sample, more data-rich exploration is possible, and in turn less sampling is required and less environmental impact is caused. Beneficiaries will include PRIVATE SECTOR COMPANIES involved in exploration, consultancy, and the provision of data and analytical equipment to industry (i.e. service companies, e.g. see PPs Olympus, Zeiss and SRK ES letters of support).

3) E-tech elements in porphyries. We will generate vital data for better global and national e-tech resource estimation. This facilitates improved targeting for specific e-techs during exploration, and improved metallurgical characterisation of them. Beneficiaries will be GOVERNMENT AGENCIES who advise on resource strategy (e.g. BGS, PP USGS), and POLICY MAKERS IN GOVERNMENT planning future clean energy strategies. PRIVATE SECTOR COMPANIES exploring for resources (see PP Anglo American letter of support) and end-users of e-techs will benefit through improved strategic knowledge of future supplies and the WIDER PUBLIC will gain through support of sustainable environmental technologies for a low-carbon society.

4) Outreach, education and training. We have planned activities to increase public understanding of resource issues (discovery, depletion, environmental and social impacts, the 'e-tech' concept), particularly through NHM outreach, and activities to encourage the uptake of the new model and proxies with professional geoscientists through training workshops, short courses and engagement at high profile conferences. Beneficiaries include the WIDER PUBLIC, PRIVATE SECTOR COMPANIES as publicly traded bodies and employers of skilled professionals and PROFESSIONAL BODIES such as the IOM3 and Mineral Deposits Studies Group (see letter of support) who support training and professional development for their members.

Publications

10 25 50
 
Description Yes -where we have presented to the general public, amateur societies or government agencies (so the presentations to the Chilean ambassador and to the Govt Chief Science Advisor would fall into this category).
First Year Of Impact 2018
Sector Other
Impact Types Policy & public services

 
Description Zeiss 
Organisation Carl Zeiss AG
Country Germany 
Sector Private 
PI Contribution Case study material, meeting and networking connections
Collaborator Contribution Analytical equipment training, follow on research, student support.
Impact Publications by Holwell, funding opportunities
Start Year 2016
 
Description Fermor Conference 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Conference hosted at the Geological Society of London. All content recorded and made freely available through YouTube. Conference brought together academics from fields of petrology, geochemistry, volcanology and ore deposits to deliver presentations on current state-of-the-art on copper porphyry mineralisation (and associated ore styles).
Year(s) Of Engagement Activity 2017
URL https://www.geolsoc.org.uk/fermor17
 
Description MDSG Conference 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact MDSG is an annual conference with attendees representing academia (all levels) and industry (particularly mineral exploration)
Year(s) Of Engagement Activity 2018
 
Description Mineralogical Society Distinguished Lecturer 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact The Mineralogical Society of Great Britain and Ireland has invited Dan Smith to tour the UK and Ireland as a 2017-18 Distinguished Lecturer. He has delivered multiple talks on his research and its impact to audiences from academia (all levels), professional societies, and amateur interest groups.
Year(s) Of Engagement Activity 2017,2018
URL https://www.minersoc.org/distinguished-lectures-17-18.html
 
Description Project Meeting (Bristol) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Project meeting, with attendance from industry partners and industry advisory board.
Year(s) Of Engagement Activity 2017
 
Description SEG Conference, Keystone, Colorado 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact International conference dedicated to ore deposit research - presented posters from ongoing research projects
Year(s) Of Engagement Activity 2018