Stimulating new exploration strategies for copper mining in Africa
Submitting Institution
University of SouthamptonUnit of Assessment
Earth Systems and Environmental SciencesSummary Impact Type
EnvironmentalResearch Subject Area(s)
Earth Sciences: Geochemistry, Geology
Summary of the impact
The Zambian Copperbelt is the largest known repository of copper on
Earth. Research at the
University of Southampton has transformed the exploration landscape in the
region, providing the
world's mining companies with new opportunities for mineral exploration in
Zambia and other
sedimentary basins in Africa. This inward investment has contributed to
rapid economic growth in
Zambia and boosted local employment. Southampton's research model has
contributed to the
discovery of two world class copper deposits, impacted on the earnings of
global mining
companies, as well as ensuring a flow of highly skilled geologists from
academia to industry.
Underpinning research
Ore deposits represent the culmination of rare and complex geological
processes. Sediment-hosted
copper deposits are recognised as some of the world's most high-quality
sources of copper
and cobalt, making them much sought-after exploration targets.
Southampton's research focused
on developing new insights into these large-scale hydrothermal systems and
generating new
models to explain how deposits were formed and preserved, with the aim of
identifying new areas
for exploration.
Zambia is the seventh largest copper producer in the world. The
100km-long Central African
Copperbelt that cuts through the north of Zambia contains world-class
copper and cobalt deposits
thought to be in excess of two billion tonnes. Yet it wasn't until 1999,
following a 25-year gap in
exploiting the resource under the influence of the Soviet Union, that the
Zambian government de-nationalised
the country's mines, reigniting overseas-led development of its copper
mining sector.
It provided an opportunity for the University of Southampton's Professor
Steve Roberts to lead
investigations into the formation of copper deposits in the region. Over
the past 14 years, Roberts,
supported by Ross McGowan, post-doctoral research fellow (2004) and PhD
student (1999-2003),
and PhD students Robin Bernau (2003-2007) and James Nowecki (2009-2012),
has carried out a
series of geological studies into the origins of Copper-Cobalt
mineralisation in the Zambian
Copperbelt. There have also been numerous projects undertaken by Masters
students.
In the early 2000s Roberts led field studies at Zambia's Nchanga mine,
one of the largest open
cast mines in the world. Researchers used a combination of structural
mapping and geochemical
techniques, including major, trace and radiogenic isotope analyses carried
out at the National
Oceanography Centre Southampton, to challenge the long-accepted assertion
that ore Cu-Co
deposits formed at the same time as the sediments in which they were
found. They showed, for the
first time, that ore formation — and crucially location — is controlled by
geological processes that
occurred much later in the evolution of the basin than previously accepted
[3.1, 3.2]. Roberts' team
found that within the 800-million-year-old basin, ore formation had
occurred over a 300-million-year
period as a result of the thermochemical reduction of sulphate and metal
enriched hydrothermal
fluids introduced during basin inversion. This new evidence expanded the
applicable exploration
criteria to include additional, substantive structures that developed
within the basin during its
evolution [3.3].
The team extended their studies to the Cu-Co deposits of the Lumwana
Mine, in Zambia's Domes
Region, through the PhD studies of Bernau (2003-2007) and Nowecki
(2009-2012). The origin of
these deposits had been the subject of much debate. However, Southampton
firmly established
that copper was located within basement rocks of the Zambia Copperbelt,
and developed along
basement shear zones [3.4]. This work amplified the results of the
earlier Southampton studies,
further developing the role of tectonics in the origins of mineralization
and broadening further
potential exploration targets in the region.
Taken together, the new studies showed that successful base metal
exploration within the
Zambian Basin requires an understanding of the contrasting styles and
timing of mineralization.
This knowledge opens significant new regions for exploration previously
dismissed by scientists
and the mining industry.
References to the research
(the best 3 illustrating quality of research are starred)
*[3.1] (2003) McGowan R., Roberts S., Foster R.P., Boyce A.J.
& Coller D. Origin of the copper-cobalt
deposits of the Zambia Copperbelt: An epigenetic view from Nchanga. Geology,
31,
497-500.
*[3.2] (2006) McGowan R., Roberts S. & Boyce A. Origin of the
Nchanga Copper-Cobalt Deposits
of the Zambian Copperbelt Mineralium Deposita, 40, 617-638.
Awarded "SGA Best Paper"
published in Mineralium Deposita for 2005 - 2006.
[3.3] (2009) Roberts S., Palmer M., Cooper M., Buchaus P., Sargent
D. REE and Sr isotope
characteristics of carbonate within the Cu-Co mineralized sedimentary
sequence of the
Nchanga Mine, Zambian Copperbelt. Mineralium Deposita, 44,
881-891.
*[3.4] (2012) Bernau R., Roberts S., Richards M., Nesbitt B.,
Boyce A.J., Nowecki J. The Geology
and Geochemistry of the Lumwana Cu (± Co ± U) deposits, NW Zambia. Mineralium
Deposita, v48, 137-153.
Funding:
2011 NERC-Stable Isotope Support- Zambian Copperbelt (IP-1241-0511) £55K
2000 NERC PhD award (NE/H524922/1) £65K
2007 Equinox Resources. Copperbelt Uranium £10K
2005 NERC-Stable Isotope Support — Zambia Copperbelt (IP/890/1105) £24K
2006 NERC PhD CASE Award — (Equinox Resources) (NER/S/A/2003) £55K
2003 Anglo American PLC — Geochemistry of the Copperbelt £140K
2002 Anglo American PLC — Geochemical Exploration Vectors in the
Copperbelt £20K
2002 NERC-Stable Isotope Support — Zambia Copperbelt (IP/755/0302) £19K
1999 Geological Society London — Fermor PhD award. Towards a new genetic
model for pre-Cambrian
sediment-hosted copper deposits £55K
Plus "In Kind" Support from: Anglo American, Equinox Resources, Vale,
First Quantum. During a
10 year period this includes all transport and accommodation costs in
Zambia and the costs of
sample shipment. Estimated value in excess of £100K.
Details of the impact
The de-nationalisation of its copper mines has powered economic growth in
Zambia over the last
decade [5.1]. The Economist ranks Zambia as one of the
world's fastest-growing economies over
this period and since 2000 average income per capita has risen more than
40 per cent. Copper
accounts for 80 per cent of Zambia's export earnings, which were 9 billion
US dollars for 2011.
Research at Southampton that successfully challenged conventional wisdom
on the formation of
copper deposits in Zambia, is credited with playing a key role in
furthering the development of the
Central African Copperbelt. Prior to studies led by Roberts, the Zambian
Copperbelt was regarded
as a mature exploration terrane, with limited opportunities for new ore
discoveries. Southampton's
intervention was timely as the renascent mining industry in Zambia was
attracting substantial
incoming investment from the world's mining giants. Insights published by
Roberts et al gave
mining companies the licence to be more creative in generating new targets
and allowed them to
manage risk more effectively. On behalf of Anglo American, Graham Brown [5.2],
Group Head of
Geosciences, comments that research at Southampton "changed our
exploration targeting
methodologies and, by encouraging us to think about the process of
formation, opened up the
whole (copper) package, and made regions prospective that weren't
prospective previously."
The lessening of risk was crucial. The new Southampton research model
gave several mining
companies, including Anglo American, Equinox/Barrick, First Quantum, Vale
and Rio Tinto, the
confidence to launch new exploration programs in the knowledge that viable
Cu-Co deposits
existed outside the regions explored under the traditional research
paradigm. The published
research provided these companies with the geochemical tools and
theoretical modelling to find
them. It has been impossible to obtain commercially confidential figures
detailing the amount of
investment global mining companies have poured into these programs. In
2012 Rio Tinto used the
new Southampton model to shift its exploration focus to a relatively
unexplored area south of the
Domes region, committing a substantive exploration budget. Adam Duffin [5.3],
Chief Geoscientist
at Rio Tinto, said: "Rio Tinto has invested considerable resources in
copper exploration in Zambia
over the past two years based on the new understanding of the geology of
the copperbelt and its
mineral resources and enjoys a strong relationship with The University
of Southampton group led
by Steve Roberts which it has drawn on in developing our exploration
strategy." World-leading
exploration consultant Richard Sillitoe [5.4] notes: "The
University of Southampton group led by
Steve Roberts has played a key role in an ongoing reinterpretation of
the geology of the Zambian
Copperbelt. This fresh vision is stimulating exploration activity in the
region, impacting on the
strategies that companies are employing and leading to increased
expenditure."
One of the most significant outcomes of this expanded exploration
activity in Zambia was the
opening, by Australian miners Equinox, of a new mine in Lumwana, in the
Domes region, in
January 2009, an asset that part motivated Barrick's takeover of Equinox
for £4.5 billion in July
2011. The population of Manyama, the nearest settlement to the mine has
increased five-fold over
the last ten years. The opening of the mine has offered employment
(directly and indirectly) to
around 3000 Zambians in the region and improved local infrastructure [5.5].
Mike Richards [5.6],
former Chief Geologist at Barrick, said: "The decade-long collaboration
between Steve Roberts's
team and our geology team in Zambia to reinterpret the geology of the
Zambian Copperbelt has
been an integral part of our exploration efforts in Zambia. It has had a
profound influence on our
exploration strategies, expenditure and success in the region."
The impact of the research has extended beyond Zambia. Mining companies
have applied the
Southampton model to similar environments in Gabon and Democratic Republic
of Congo (DRC).
Canada's Ivanplats led the discovery of the Kamoa mine near Lubumbashi,
the mining capital of
DRC, in 2011. DRC produces more than three per cent of the world's copper
and half its cobalt.
Kamoa ranks as the world's largest undeveloped high-grade copper
discovery, with 739 million
tonnes grading 2.67% copper. In Gabon another Canadian firm Armada
Exploration is investing
more than $5 million in exploration for copper in a region with a similar
formation history to the
Zambian Copperbelt [5.7].
Through research led by Roberts, a number of highly skilled scientists
that trained at Southampton
have filled high-profile industry posts. PhD students McGowan and Bernau
are CEO at Armada
Exploration and Project Geologist at Micon International respectively.
McGowan was actively
involved in the discovery of the Kamoa Deposit in DRC. Masters student
Adam Burley (1996-2000)
was, until July 2013, President of Kennecott Eagle Minerals Co. and is now
managing strategy,
growth and innovation for copper at Rio Tinto.
Roberts has also actively shared his expertise and research findings with
industry, as is
demonstrated by his pivotal role in a recent workshop. In June 2013
Roberts organised and
delivered a capacity-building workshop, African Metallogeny II — Base
Metals in Basins in Kitwe,
Zambia. The aim of this workshop, supported by UNESCO, "is to train
young African geoscientists
in the specific field of metallogeny, i.e. practical aspects of the
genesis of ore deposits that can be
applied in the formulation of future exploration strategies" [5.8].
The course was attended by over
50 delegates from 14 countries and twenty mining companies such as Rio
Tinto, First Quantum
and Barrick. Feedback from delegates was very positive, particularly
praising the link between
theory and practical exposure to example rocks. Delegate feedback
included: "The workshop
structure was fantastic with the right balance between lectures, mine
visits and core viewing. I
personally enjoyed that while looking at the core you guys assigned
tasks that made our
observation of the rocks, alteration and mineralization styles and
discussion about stratigraphic
positioning much more objective.", "The workshop was one of the
best that I've ever participated in
10 years of professional life. I believe that you guys had found the
right structure for future events"
and "Thanks for organising an excellent workshop. The Barrick team
really appreciated the effort
and time you put into organising the workshop and the seamless execution"
[5.9].
Sources to corroborate the impact
[5.1] http://www.economist.com/blogs/baobab/2013/05/development-africa
[5.2] Group Head of Geosciences, Anglo American.
[5.3] Chief Geoscientist, Rio Tinto.
[5.4] Exploration Consultant.
[5.5] http://barrickbeyondborders.com/2012/12/managing-in-migration-at-lumwana/
and
http://www.eib.org/infocentre/press/news/stories/2010-august-02/lumwana-stimulates-economic-growth-in-zambia.htm
[5.6] Chief Geologist, Barrick.
[5.7] Chief Executive Officer, Armada Exploration Limited.
[5.8] Industry workshop: African Metallogeny II — Base Metals
in Basins , Kitwe, Zambia, June
2013 http://www.meetingpoints-mining.net/2013/02/2nd-sga-seg-unesco-iugs-short-course-on-african-metallogeny/
[5.9] Report for SGA Council Meeting (draft).