Assoc/Prof Marco Fiorentini
Principal Research Fellow/Future Fellow
Earth and Environment, School of
- Contact details
- School of Earth and Environment
The University of Western Australia (M006)
35 Stirling Highway
CRAWLEY WA 6009
- +61 8 6488 3465
- +61 8 6488 1178
- Personal homepage
- PhD W.Aust.
- Marco has over 4 years of academic and industry experience in the understanding of orthomagmatic mineral systems, with a special interest towards Archaean komatiites and Proterozoic komatiitic basalts and ferropicrites. Marco’s recent experience has focussed on the link between the geochemical features of Ni-Cu-PGE deposits and the specific geological conditions that occurred in the Early Earth, through the study of non-mass dependent sulfur isotope fractionation in sulfides from selected ore deposits around the world. In addition, Marco is currently investigating the highly controversial role of volatiles in komatiite and ferropicrite petrogenesis.
Marco’s research interests also display a very strong applied focus, driven by the desire to provide the mineral industry with new robust cost-effective exploration tools that can be utilised in exploration programs. In this regard, Marco’s major contribution has been in the field of magmatic sulfide deposits.
During his PhD at the University of Western Australia, Marco examined the role of chromite in the fractionation and concentration of the platinum-group elements (PGEs). Specifically, as part of the AMIRA P710 project, he developed a novel lithogeochemical technique based on the contrasting geochemical behaviour of the PGEs in sulfide-supersaturated and sulfide-undersaturated komatiites. This method provided the resource industry with an innovative PGE-based exploration technique, which can be applied in greenfield terrains to assess the fertility of komatiites.
In August 2005, Marco took up the position of Research Fellow at the newly established Centre for Exploration Targeting at the University of Western Australia, where he continued his work within the framework of the AMIRA P710a project (following the successful outcomes of the AMIRA P710 project), which aimed at developing PGE-based vectors towards mineralised environments.
In 2008, Marco started a new appointment as an APDI Research Fellow within the Centre for Exploration Targeting at the University of Western Australia. He aims at defining the tectonostratigraphic controls on the localization of Archaean komatiite-hosted nickel-sulfide deposits and camps in the Yilgarn Craton. The primary aim of this project is to develop a superior metallogenic model to help target areas of high prospectivity for komatiite-hosted Ni-sulfide deposits, based on an improved understanding of the stratigraphy and lithospheric structure of the Yilgarn Craton of Western Australia.
Marco worked in numerous laboratories in Australia (at GEMOC, Macquarie University in Sydney and at MONASH University in Melbourne) and overseas (Carnegie University, Washington, USA, and CPRG-CNRS at Nancy, France), and he is involved in numerous research initiatives through a range of collaborative projects with other research institutions in Australia, Canada, Finland, Russia, Italy and France.
- Key research
- 1. Nickel Mineral system analysis
- 2. Research and development of PGE-based exploration tools towards Ni-Cu-PGE mineralisation associated with mafic and ultramafic systems
- 3. The Early Earth
- 4. Geochemistry of PGEs
- 5. Role of volatiles in the petrogenesis of Precambrian mafic and ultramafic systems
- 6. Role of chromite in the fractionation and concentration of the PGEs
- 7. The use of in-situ stable isotope determination as a tracer of mantle metasomatic processes
- Future research
- Opportunities for Postgrads and Honours students: 1. Definition of vectors to massive sulfides at Eagle Ni-Cu-PGE deposit, Michigan, USA (Masters Level, 1-2 years, Rio Tinto)
This project aims at defining vectors to massive sulfides at the Eagle Ni-Cu-PGE deposit, Michigan, USA. The study will investigate the genesis of the disseminated sulfide mineralisation, and assess its spatial and genetic relationships with the formation and localisation of massive sulfide horizons. It is envisaged that the characterisation of the three-dimensional platinum-group element variation in selected areas of the ore environment will shed light on the ore-forming process and provide invaluable constraints on vectoring parameters in the known ore environment towards higher-grade and higher-tenor areas, and towards potential extensions of the deposit. The three-dimensional geochemical characterisation of the ore environment will not only constrain the genetic aspects related to the ore forming process, but more specifically permit the definition of vectoring parameters in and towards massive sulfides.
At the Eagle deposit, the project aims to:
· Characterise the three-dimensional variation of platinum-group element and nickel tenor in massive and disseminated sulfides;
· Define tenor (in multiple metals, including Ni and PGEs);
· Generate a model for the genesis of different types of orebodies within the deposit; and
· Determine vectors to higher grade portions of the known orebody or extensions of the orebody.
2. Understanding nickel mineral systems in the Archean Yilgarn Craton: Quantifying melt-lithosphere interaction in space and time (PhD Level, 3 years)
This project will investigate how geotectonic setting, nature of the lithosphere, and plume-derived magmas may affect the prospectivity of ultramafic horizons at the terrane scale to answer the question why komatiite Ni-sulfide systems form camps in specific belts. It will evaluate whether Ni deposits form in specific tectonic or basin settings by a combination of favourable events close to the locus of komatiite emplacement (e.g. crustal assimilation, sulphur source, etc.), or whether a significant mantle source component is involved in the Ni-sulfide ore-forming process.
Comparative studies of komatiites from the Eastern Goldfields and the Abitibi belt of the Superior Province in Canada show that presence of large excesses of cumulate olivine in komatiite flows is a key indicator of highly prospective komatiite units at the terrane scale. One hypothesis to be tested is whether this feature is the result of voluminous and sustained magmatic episodes that may be linked to specific tectonic environments. Critical factors may be the age, structure and bulk density of the lithosphere through which komatiite magmas ascend. This study will aim to model and quantify melt-lithosphere interactions, mantle source or source process variations, and map them in space and time.
I am currently supervising three postgraduate students:
Mr Geoff Heggie, who started his PhD at UWA in September 2006. He investigates the scale of the geochemical signature associated with ore-forming processes in different types of komatiites;
Mr Marek Locmelis, who started his PhD at Macquarie University (Sydney) in August 2006. He investigates the role of chromite in the fractionation of platinum-group elements in order to define geochemical vectors to mineralisation in komatiites and komatiitic basalts;
Mr Ian Pryor, who started his Honours’ in March 2008. He investigates the genesis of anomalously enriched sulfide-free PGE horizons in komatiites.
- Funding received
- In the past three years I have been successful in obtaining four major research grants:
· ARC Linkage project LP0776780 (800k AUD over three years): Tectonostratigraphic controls on localisation of komatiite-hosted nickel-sulfide deposits and camps;
· AMIRA/MERIWA Grant (500k over three years): Controls on Platinum Group Element Variation in Mafic and Ultramafic Magmatic systems;
· ARC Linkage in collaboration with ANU (200k AUD over two years): Experimental constraints on Platinum-Group Element geochemistry: developing lithogeochemical exploration tools for nickel sulfides in mafic and ultramafic systems;
· NASA Astrobiology Institute (10k USD over one year): Non-mass dependent sulphur isotope characterisation of komatiite-hosted magmatic sulfides
In addition to the research grants listed above, in the past 3 years I have secured 3 fully-funded scholarships (IPRS) for international students and I have been successful in receiving funds for pilot studies in a broad range of fields from the Society of Economic Geologists and the Siberian Branch of the Russian Academy of Sciences.
- Member of the Geological Society of Australia (GSA), Society of Economic Geologists (SEG) and Society for Geology Applied to Mineral Deposits (SGA).
- I am involved in teaching selected modules within the undergraduate program of the School for Earth and Geographical Sciences. In addition, I teach specific course units on Ore Deposit Conceptual Models within the Master Program on Ore Deposit Geology and Evaluation (www.cet.uwa.edu.au).
The coursework Masters program is designed for geoscientists who want to gain up to date knowledge and skills in economic geology and mineral exploration. The course at UWA is part of the national Minerals Geoscience Masters program and is supported by the Minerals Council of Australia.
The program is run jointly between the Centre for Exploration Targeting (UWA), CODES (UTAS), EGRU (JCU), VIEPS (Monash) and the CRC LEME (ANU). In addition to my academic teaching duties, I actively organise and deliver workshops on latest advances in research on orthomagmatic deposits, which are specifically designed for industry.
- Current projects
- 1. Tectonostratigraphic controls on the localisation of Archaean komatiite-hosted nickel-sulfide deposits and camps in the Yilgarn Craton (ARC Linkage)
This study aims to:
Adopt a scale-integrated multidisciplinary approach to reconstruct the volcanic basins and the overall geodynamic environment at the time of komatiite emplacement;
Constrain key tectonostratigraphic controls on nickel mineralization and place known distributions of nickel systems into the wider geodynamic environment;
Investigate the roles of mantle source, melt-lithosphere interaction and surface processes in the generation and localization of highly mineralised camps within komatiite belts.
2. Controls on Platinum Group Element Variation in Mafic and Ultramafic Magmatic Systems (AMIRA P710a/ MERIWA)
The principal objectives of the project are to:
Define the scale of the geochemical footprint associated with the nickel-sulfide ore-formation process in variably mineralised komatiites;
Investigate the PGE systematics of mafic and ultramafic systems in a range of petrogenetic environments;
Look into the role of pyroxene and oxide phases in the fractionation and concentration of PGE in non-komatiite systems, in order to apply the Ru fertility indicator to more evolved systems;
Develop PGE-based vectors towards mineralised environments within mineralised mafic and ultramafic sequences.
3. Experimental constraints on Platinum-Group Element geochemistry: developing lithogeochemical exploration tools for nickel sulfides in mafic and ultramafic systems (ARC Linkage in collaboration with ANU)
Essential to any development in the application of PGEs to nickel-sulfide lithogeochemistry is a substantial advance in the quantitative determination of PGE partitioning behaviour during segregation and fractionation of silicates, oxides, and sulfides during the evolution of mafic and ultramafic magmas. Consequently, this study aims to address three areas of experimental investigation:
Experimental investigation of PGE partitioning in sulfides and chromites at varying conditions of T, P and fO2;
PGE solubility in silicate and sulfide melts as a function of sulfur (S), tellurium (Te), bismuth (Bi), arsenic (As) and water (H2O) concentrations;
Experimental investigation of PGE diffusivity in sulfide and chromite.
4. Three dimensional X-Ray tomographic imaging of magmatic sulfides (iVEC project in collaboration with CSIRO)
In this project we aim to utilise three-dimensional X-ray tomographic imaging techniques in order to image and characterise the morphology of magmatic sulfides in igneous cumulates. Such a study may have crucial outcomes since the formation of nickel-sulfide ores, the behaviour of sulfide liquids during mantle melting, and potentially the segregation of the Earth’s core, are all controlled by the ability of sulfide liquids to migrate through the pore space of partially molten silicates.
5. Role of volatiles in the petrogenesis of mafic and ultramafic magmas (ARC Discovery and Russian Academy of Science grant in collaboration with Irkutsk Crust Research Centre)
This project investigates the highly controversial role of volatiles in the petrogenesis of Archaean and Proterozoic komatiites, komatiitic basalts and ferropicrites. In addition, the study focuses on the possible implications that the occurrence of volatiles at various stages during the petrogenesis and evolution of mafic-ultramafic magmas may have in the generation of large Ni-Cu-PGE sulfide deposits.
6. The Sulfur Cycle in the Early Earth (NASA Pilot Study and ARC Discovery Proposal)
This project represents an ongoing effort to delineate the S source for Archean komatiite-hosted magmatic iron-nickel sulfides, whether mantle- or crustal-derived. Our current multiple sulfur isotope data for komatiite-hosted iron-nickel sulfides, sulfidic black shales and hydrothermal exhalative massive sulfides from the ca. 2.7 Ga Agnew-Wiluna Greenstone Belt (Western Australia) and ca. 2.7 Ga Abitibi Greenstone Belt (Ontario, Canada) suggest that sulfur from hydrothermal exhalative massive sulfides hosted by felsic volcanic rocks in the footwall of the komatiite sequences was the major S source for the komatiite-hosted iron-nickel sulfides. However, the database is still relatively small and more data need to be generated.
- Research profile
Research profile and publications