Our group

FlexPet Lab


The FlexPet Lab hosts a very active and growing group of BSc, MSc, and PhD students, postdoctoral researchers, and visitors, working on mineral-fluid and mineral-melt interaction on the surface of the Earth and in its interior, and from the present time back to the earliest history of our planet. Including;

Naomi Barshi

Deformation-enhanced element mobility in minerals as a tool to quantify palaeo strain-rates

MSc 2015, co-advised by Christie Rowe

A.B. Cum laude with High Honors in Geosciences, 2012, Smith College, Massachusetts, US

My primary research interest is understanding tectonics and crustal deformation through a variety of tools from microscopic to macroscopic scales, from the lower crust to the surface, from orogenesis to earthquakes. Currently I investigate deformation-enhanced element mobility in feldspars to gain insight into strain rate in actively deforming shear zones. Feldspars develop chemical zoning during mineral growth. Diffusion of element across these zones and between mineral grains ultimately destroys this magmatic zoning, and deformation expedites the process. I will conduct fieldwork to sample across a gradient of deformation intensity. I will use these these variably deformed samples to calibrate the effect deformation intensity has on element mobility. I will track element mobility use McGill’s electron microprobe and GEOTOP’s laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS).  

Previous research and field experiences span field assisting for Field Rheology group-mate Nils Backeberg in the Archean Marmion Terrane of the Wabigoon Subprovince, Superior Province, Ontario, and some undergraduate research projects. My honours thesis explored structural characteristics of a deeper crustal shear zone in the Mesoproterozoic Central Metasedimentary Belt of the Grenville Province Keck Geology project, Bancroft area, Ontario, Canada, co-advised by Jack Loveless and Michelle Markley). I am also interested in landscape processes and examined storm-related geomorphic changes on Plum Island, a barrier island on the northeast coast of Massachusetts, USA (independent undergraduate research project advised by Bob Newton).

Calcite precipitated by organisms has a characteristic minor and trace element composition, because organisms will actively take up and excrete a highly selective set of elements. Laure is investigating the trace element composition of calcite grown by organisms and contrasts this with chemically synthesized calcite. The aim is to find patterns in trace element behaviour that can be used to identify whether a certain carbonate deposit formed with involvement of life.

Laure Wassen (BSc 2015) Life’s signature in calcite trace element compositions

Miguel Cruz

Systematics of element exchange between phengite and fluid in subduction zones and its impact on global element cycling

Osisko Postdoctoral Researcher

PhD  Stanford University, 2018

MSc  University of California, Los Angeles, 2010 

BSc  University of California, Los Angeles, 2007 

Sri Budhi Utami

Gypsum as a recorder of element mobility

MSc 2015, co-advised by Bassam Ghaleb

BSc (Hons) Geological Sciences 2013, University of British Columbia

Volcanoes are complex and dynamic systems that provide crucial insight into the Earth’s interior, while caves are valuable recorders of past climate change. Both settings are connected by fluid mobility and circulation in the Earth. For my research I am focusing on developing gypsum, a mineral that precipitates in equilibrium with its fluids, as an indicator mineral for volcanic activity and climate change. I will use natural gypsum from Kawah Ijen volcano in East Java, Indonesia and a cave in the Philippines to reconstruct variations in fluid history from both settings. I will experimentally grow gypsum doped with trace elements to determine partition coefficients between gypsum and the original fluids. I will also use the Electron Microprobe, Inductively Coupled Plasma Mass Spectrometer (ICP-MS) and Laser Ablation ICP-MS (LA-ICP-MS) to analyze trace elements compositions of gypsum. Finally I will determine disequilibrium ages of natural gypsum using alpha and gamma spectrometry to reconstruct fluid composition history and identify markers for volcanic eruptions and past climate change.  

My past research experience include geochemical characterization of rocks and glasses from shield-stage dikes in Kauai as part of my undergraduate thesis, under the co-supervision of Dominique Weis and Michael. O. Garcia. My primary aim is to determine the dikes’ geochemical signature in relation to the Loa and Kea geochemical trends to understand the geochemical evolution of the Hawaiian mantle plume. I also assisted in analyzing global coral bleaching severity as part of climate change research with Simon Donner. I have also conducted undergraduate research group projects ranging from investigating pumice morphology from Mt. Meager, British Columbia to the geochemistry of the Atlantic Mid-Ocean Ridge basalts. Field experiences include southern British Columbia (Okanagan, Salt Spring Island, Mt. Meager) and the Big Island of Hawaii.


Gunawan et al. (2016) New insights into Kawah Ijen's volcanic system from the wet volcano workshop experiment. Geological Society London Special Publications 437

Haihao Guo

Titanite and tourmaline as indicators of trace element mobility in metamorphic, magmatic and ore forming systems

Osisko Postdoctoral Researcher

PhD Bayerisches Geoinstitut (BGI), University of Bayreuth, Germany, 2017

MSc University of Science and Technology of China, 2013 

MSc University of Science and Technology of China, 2011

I will establish trace elements in tourmaline as a petrogenetic indicator tool, including developing a suite of new tourmaline reference materials. I will also experimentally determine the systematic partitioning of trace elements among titanite, melt and fluid at elevated temperatures and pressures in order to understand the formation of Mo-Sn-W-Ta-Nb mineralization associated with evolved intrusions, and the behaviour of high field strength elements in subduction zones. The influence of fluorine on the element partitioning and stability of titanite will be studied by high temperature and pressure experiments.

Previous studies include experimentally simulate the transfer of metals and volatile elements in magma chambers; experiments on gold in magmatic and related hydrothermal systems; and measurement on dielectric properties of water and electrical conductivity of NaCl bearing fluids under high-pressure/temperature conditions.

FlexPet Graduates - PhD

Majken Poulsen

Corundum genesis in Greenland

PhD student, co-advised by Nynke Keulen, Robert Frei and Jochen Kolb

MSc from University of Copenhagen

The mineral corundum (Al2O3) is widely known for its ruby and sapphire gemstone varieties. Pure corundum is colourless, and the colour of ruby (red) and sapphire (all other colours) are caused by trace impurities in the crystal lattice including Fe, Ti, V, Ga and Cr. The formation of corundum is often related to plate tectonic events such as continental collision and continental rift zones. Corundum is formed in a geological environment with depletion in silica and high Al content, such as marbles, mafic to ultramafic rocks, metamorphic rocks and Al-rich shales. Most ruby and sapphires are mined worldwide from secondary deposits and the original geological environment is thus lost and difficult to determine, but some geochemical signals can indicate a geological environment based on the concentration of certain trace elements as well as the oxygen isotopic composition of the gemstone.

The work in my Ph.D. is focused on corundum from the Tasiilaq area in East Greenland, where the corundum is still sitting in the host rocks and the geological environment can be studied directly. The corundum is formed in ultramafic rocks in reaction with pegmatite veins. The trace element diversity and the mobility of the elements will be examined in the host rocks and the pegmatite veins. The trace element composition and isotopic composition of Pb, Sr, Sm/Nd and O from the pegmatites can indicate the origin of the fluids triggering the formation of corundum, and O-isotope compositions measured in the corundum will reflect the composition of the host rock. The geological environment will also be simulated in experiments at controlled pressure, temperature, fO2 and composition. Heat treatment of ruby and sapphire is very common in the gemstone market, and this is done in order to increase the colour intensity or clarity of the gemstone .The effect from heat treatment on the trace element distribution in the gemstones is poorly known, and test will be performed on the corundum before and after heat treatment to investigate this.

Marion Saby

Metal origins in geothermal systems

PhD, co-advised by Daniele Pinti

MSc Université de Québec à Montréal

Volcanic environments are recognized as modern analogues of mineralized fossil magmatic-hydrothermal systems. The mobilization and redistribution of metals that takes place in these systems can potentially lead to ore formation. But the respective contribution of magma degassing and rock leaching to the metal content of active hydrothermal/geothermal systems is still debated. To answer this question, my Ph.D. project will focus on the behaviour of volatile metals in these active environments and use noble gases as tracers of their sources and pathways. Among noble gases, helium is commonly used to differentiate mantle and crustal sources of fluids in active volcanic systems. Here, I will use helium and argon to trace the respective contribution of magma degassing and rock leaching to the metal content of surface and deep fluids in active volcanic environments of Iceland and New-Zealand.

In previous research, I worked on hydrogeological systems and studied the impact of rock leaching on the geochemical composition of groundwater. I showed that highly mineralized formations heavily impact groundwater quality. I also investigated groundwater residence times and used noble gases to differentiate water sources and pathways in the aquifer system. Along with rock types, long residence times impact the groundwater element concentrations.

Current position:

PhD student at the Asian School of Environment at Nanyang Technological University, Singapore

Tourmaline commonly shows prominent compositional zoning. One type of zoning observed is hourglass sector zoning, which forms because of small positive and negative charges induced on growth surfaces that are inclined relative to tourmaline’s polar c-axis. Previous compositional studies of metamorphic tourmaline samples have revealed that the partitioning of major elements among these sector zones depends heavily on temperature. As the temperature at the time of growth increases, so do the bond lengths and vibrations at tourmaline’s crystallographic sites, hence the partitioning of elements among growth surfaces is diminished. Because the diffusion rates for elements within tourmaline are known to be negligibly low, the distribution of elements among the sectors can be assumed to be the same as at the time of growth. This means that the temperature record in sector zoning is preserved, and, using partition coefficients from different stages of a tourmaline crystal’s growth, a temperature history can be determined. Tourmaline is present in a large range of geological settings, and so the study of its composition provides an invaluable source of data for reconstructing the past physical and chemical conditions of source melts and the growth history of the host rocks.

In this study, the compositions of four pegmatite tourmaline samples were analyzed, and the compositional trends and zoning styles of two of the samples investigated in detail. Elemental intersector partition coefficients were determined to evaluate their use as a qualitative temperature record for igneous tourmaline samples.

Catherine Armstrong

Composition and zoning in pegmatite tourmaline

BSc 2014

Current position:

PhD student at the University of British Columbia, Vancouver, Canada

Olivia Dagnaud

Geochemical mapping of the abandoned Mine de la Rodde, Massif Central, France

BSc 2017

The Mine de la Rodde in central France was a major producer of antimony in the late 19th century. However, mining at this site can be traced back to Roman times, when the focus was on silver. The mine occupies a forested valley on the boundary between paragneisses and the Celoux orthogneiss, with waste tailings, shafts and abandoned mine buildings scattered around. This project seeks to geochemically map the valley around the mine site to determine the geological background concentrations and the imprint of the mineralization and the mine workings. It will use data collected by grid sampling and analyzed for major and trace elements by XRF.

Torie Roseborough

Investigating Laser-Ablation ICP-MS as a method to obtain bulk rock compositions

BSc 2017

Laser ablation ICP-MS on pressed powder pellets provides an interesting method to obtain the major to trace element composition of geological materials. This project investigated the precision and accuracy of this method for powdered rock samples. It was found that the quality of data depends strongly on the grain size of the powder, with better data for more finely ground material. Finer grained material also produces more resilient pellets.

Stan Roozen

Tourmaline-fluid element partitioning

PhD student, co-advised by Kristoffer Szilas (University of Copenhagen)

MSc from ETH Zürich, Switzerland

In my research, I aim to reconstruct the major and trace elemental composition of crustal fluids with the mineral chemistry of tourmaline. In order to get the major elemental composition of the fluid, I measure the thermodynamic properties of the various endmembers of the tourmaline supergroup minerals and integrate this data into internally consistent databases, so it can be used in solubility models. The same data can also be used for pseudosection thermobarometry. For the trace elemental composition of the fluid, I measure partition coefficients between fluid and synthesized tourmaline and fit the experimental data to a lattice strain model with the help of speciation prediction from phase equilibria modelling. The solubility, lattice strain and pseudosection models are used to reconstruct the fluid evolution from a natural tourmaline in an Archean subduction zone in the Tartoq greenstone belt in SW Greenland.

Catherine Crotty

Trace element reconstruction of Archean hydrothermal fluids

PhD student, co-advised by Kristoffer Szilas (University of Copenhagen)

MSc from University of Copenhagen, 2017

B.Sc. Hons. Geology, University College Dublin, Ireland, 2014

Currently, there are few direct samples of Archean fluids that have been preserved in pristine condition. Previous methods have involved analysis of chemical sediments and fluid inclusions but are only quantitative for the major elements. In my PhD, I will attempt to reconstruct the trace element composition of hydrothermal fluids from the Archean. This will be done in three steps: 1. Determining the P-T path of the 3.2 Ga Tartoq greenstone belt from SW Greenland, by thermodynamic modelling 2. Experimentally determining partition coefficients between relatively abundant minerals found in supracrustal belts and a hydrothermal fluid. 3. Applying the experimentally derived partition coefficients to minerals for which the pressure, temperature and composition are known, and that preserve the fluid they interacted. This will allow a quantitative reconstruction the trace element composition of Archean fluids that we no longer have direct access to.

Previously I worked in the Andes, where I carried out a geochemical and petrological study of Miocene to Pliocene volcanism in the Southern Volcanic Zone. Along with a Pb, Sr and Nd isotopic analysis, using TIMS, I was able to geochemically track the transition from back arc to fore arc volcanism, as the subduction slab steepened from the Miocene to the Pliocene.

Nick Ogasa

Putting quantitative constraints on the fault-valve model for the formation of gold mineralisations

MSc student, co-advised by Jamie Kirkpatrick

Fault-valve behaviour is a gold-mineralizing mechanism that has frequently been used to explain the formation of orogenic gold deposits around the world. This conceptual model involves the cycling of fluid pressure in a reverse fault system, resulting in repetitive hydrofracturing and mineralization events. While many geological observations have been made that support the existence of fault-valve behaviour, quantitative constraints are lacking. My research involves using microstructural analysis, tourmaline thermometry, pseudo-section analysis, and tensile strength experiments to constrain the shear stress magnitude and pressure drop during fault valve behaviour in Au-bearing quartz-tourmaline veins at Val d'Or, Quebec. The results from this research will allow us to test the viability of the fault-valve model as a gold-mineralizing mechanism at Val d'Or and give us a better understanding of the role of fluid pressure cycling in the generation of gold deposits.

Haylea Nisbet

Th mobility in REE hydrothermal systems

MSc, co-advised by Artas Migdisov, Hongwu Xu and Willy Williams-Jones

Project in collaboration with the Los Alamos National Laboratory, US

The interest in the Rare Earth Elements (REE) has grown considerably over the past few decades because of their significant application to today’s energy and environmental technologies. With this growing demand requires new information on the geochemical processes involved in enriching these elements to economic concentrations. One of the main factors controlling the economic feasibility of extraction is the presence of Th which, due to its intrinsic radioactivity, leads to higher costs of recovery for mining companies. Thorium, a tetravalent actinide, is commonly associated with the REE because of its ability to incorporate into the structure of two of the main REE ore minerals, monazite and xenotime. Hydrothermal fluids often play an important role in mobilizing, and fractionating these elements to ore quantities, and while we generally have a good understanding of the behavior of the REE in hydrothermal systems, our knowledge of Th is essentially non-existent due to a lack of high T thermodynamic data.

The focus of my research is thus to understand the behavior of Th in hot, aqueous fluids, and to determine the environ-mental conditions that lead to the fractionation of the REE and Th in hydrothermal systems. This will be done experi-mentally by deriving essential thermodynamic data for Th solubility and speciation in aqueous solutions at elevated temperatures, which can be incorporated into models simulating natural systems. The objective is to derive a genetic model that describes the physicochemical conditions that lead to Th-enriched and Th-depleted REE ore deposits.

Rare metals have become an exploration focus in recent years, as they are important components in electronics and green energy technologies. A number of peralkaline igneous systems in Northern Canada contain potentially important cumulates of zircon, which are highly enriched in REEs. I am investigating how trace elements partition between pyroxene, peralkaline melts, and associated fluids. I will perform high temperature - high pressure experiments, and will undertake a field study of natural peralkaline systems to test this new tracer for melt and fluid composition.

Previously, I used radiogenic isotopes to investigate melt sources and the redistribution of crystal slurries in the Neoproterozoic Franklin Large Igneous Province, Victoria Island, Arctic Canada (MSci). Here I worked with Dominique Weis and Jean Bédard, as part of the Geological Survey of Canada Geomapping for Energy and Minerals project. During my undergraduate degree I visited field sites spanning from rainy Scotland to sunny Syros (Greek Cyclades) where I spent a summer mapping exhumed HP metamorphic terranes.

Charlie Beard

Rare Earth Elements in alkaline intrusions

PhD 2017, co-advised by John Stix

MSci Geology, University of Bristol, UK, 2012 

Longbo Yang

Fluorite as a monitor of fluid composition

PhD 2018, co-advised by Iain Samson

MSc Mineralogy, Petrology and Ore Geology, 2013, China University of Geosciences (Beijing)

BS in Geology, 2010, China University of Geosciences (Beijing), China

I study the chemical composition of ore-forming fluids in ore deposits.  Currently I’m looking at establishing fluorite as a monitor of fluid composition. Fluorite is a common gangue mineral in ore deposits from low temperature base metal deposits to high temperature magmatic deposits. As fluorite grows from the ore fluids, it records the composition of the fluids through element uptake by partitioning, which could be modeled and predicted. Fluorite therefore could be used to obtain information about the concentration of elements in the ore fluids. My PhD study will focus on determining the elements partitioning behavior between fluorite and fluids experimentally under various pressure-temperature conditions, which would involve developing experimental methods for fluorite synthesis, obtaining data of element partitioning coefficients and modeling partitioning behavior. These data and models would be applied to a variety of fluorite-bearing ore deposits, including Pb-Zn deposits in France and deposits associated with the El Capitan pluton in the US, to reconstruct the elemental composition of the ore fluids.

Previous research includes the study of geological and geochemical characteristics of the Jinshan gold deposit in Xinjiang, China for undergraduate thesis and the study of ore-forming mechanism of the Huachanggou gold deposit in Shaanxi, China for Master thesis. Both projects involved microscopic observation, electron microprobe analysis, stable isotope analysis and fluid inclusion analysis.

FlexPet Graduates - MSc

FlexPet Graduates - BSc

Current position:

MSc student at Dartmouth College

Romain Lauzeral

A gypsum record of volcanic activity at crater lakes

PhD student, co-advised by Kim Berlo

MSc from Université Blaise-Pascal, Clermont-Ferrand, France, 2018

Volcanic crater lakes are an open window into the underlying magmatic-hydrothermal system. Their changing water chemistry over time provide a formidable opportunity to monitor volcanic activity. However, previous studies lack perspective regarding the geochemical measurements, as records only became prevalent in the late 20th-to early 21st century. Extending these records back in time would aid monitoring and hazard prediction. My PhD study will address the potential of gypsum as a recorder of volcanic activity in order to fill this historical gap. Gypsum is an evaporite mineral: it preserves the chemical composition of the fluid from which it precipitates. However, knowledge of the partition coefficients is required if one wants to use gypsum as an accurate proxy of original lake composition. To this end, I will synthetize gypsum with the help of a flow-through autoclave to experimentally determine element partitioning between the mineral and the acidic fluid. I will also develop new methods that allow for rapid and concomitant quantification of major and trace elements by tandem LA-LIBS, of both gypsum and water samples. Chemical analysis of natural samples from two target volcanoes (Kawah Ijen and Poás) coupled with experimentally determined partition coefficients will allow me to infer and reconstruct the temporal chemical evolution of acidic crater lakes

I am interested in trace element partitioning in subduction zones, especially between micas and fluids; argon diffusion and partitioning and how it relates to the problem of excess argon in micas; calcium diffusion and the thermochronologic significance of mica potassium-calcium ages; and other interactions between minerals and fluids in the deeper, hotter geologic environments.