Medhi Bida is a doctoral student at IGD and he was among the first to receive a mobility grant Mobi-doc. Discover his project! He will go to Arizona State University to study the economic dynamics of cities.
The gap in economic wealth is widening between large and small cities. What are the factors behind this growing inequality?
What are the main implications of your scientific project?
Mehdi Bida: Since the 1980s, some American, but also European, cities have increasingly concentrated wealth and the profiles that create economic wealth (generally people with a high level of education). At the same time, they are becoming less and less viable for people working in sectors with low level of economic value added. Through a systemic approach, I would like to understand the role of the micro dynamics of different skill profiles in this macro growth of inequalities between cities. The aim is to better understand the impact of certain factors, such as the automation of industrial production, on the evolution of the economic performance of cities according to the professional skill profiles (such as financiers, computer scientists, skilled workers, etc.).
What will you gain from this mobility?
MB: At the scientific level, this mobility will enable me to collaborate (with all the contributions that come with it) with specialists in American urban economies and their modelling, which are the two central aspects of my thesis. Besides, this mobility will also offer me the opportunity to meet new people, to extend my professional network, but also to enrich my vision of my research field. I will indeed be working with researchers whose approaches and specialisations differ somewhat from those of the researchers in the field at the IGD.
Why have you chosen the Arizona State University?
MB: I recently came up with the idea of collaborating with Dr. Shade Shutters, who will supervise my work at ASU. This project became more concrete when I interacted with Prof. Céline Rozenblat and him regarding my thesis, but also when I collaborated with him on a project about the economic resilience of Russian cities, alongside other members of our research group. Given Shade Shutters’ knowledge and experience of the systems approach to US urban economies, we immediately saw the value of collaborating with him on one of the papers that will be in the body of my thesis.
Any advice for future applicants for mobility projects?
MB: Preparing the application can be daunting, but don’t get discouraged. Writing the project application proved to be very formative for me. It allowed me to clarify certain points relating to my scientific knowledge. Of course, putting together the application required mastering the scientific aspects, the motivation, the vision, etc. My mastery of these aspects also progressed thanks to the development of the project.
So I would have two pieces of advice: firstly, don’t hesitate to go for it, even if there are points that are not yet clear! Secondly, during the development phase, you should be prepared to question the points that seemed clear at the outset, but which turn out to be failures in the argumentation and coherence of the project.
In a recent publication, Michael Jollands, Elias Bloch and Othmar Müntener present new measurements of Titanium diffusion in quartz. Their results differ from previous studies by more than two orders of magnitude. These new findings allow a re-evaluation of the chronology and contributed to the award of the EGU 2021 Prizeto its first author.
Rewriting the story of a giant eruption
The impressive Bishop Tuff geological formation in California is the result of a colossal silicic eruption about 800,000 years ago. The resulting flow spreads over 1000 km2 and is 150 m thick.
Understanding big silicic volcanic eruptions, their origin, their potential impact on society and the environment is not easy. And for good reason: such eruptions have rarely been observed in modern times. The deposits of eruptions preserved in the geological record are therefore our best allies in describing the past and predicting the future. The Bishop Tuff is a prime testing ground in this regard.
Through the study of quartz, the mineral that typically forms in silicic magmatic systems and fuels these eruptions, geologists attempt to retrace the history of Earth’s dynamics. Quartz contains the records processes from their initial crystallization, their growth, to their final cooling at the Earth’s surface. Quartz has the ability to reveal the thermal, chemical and temporal evolution of magmatic systems.
Calibrating this tool as well as possible is therefore essential. This is why this new study is a fundamental step.
Titanium: slower than expected!
Titanium (Ti) is one of the many trace elements – in minute quantities – that substitute for silicon in quartz. The diffusioncapacity in the mineral, which is strongly dependent on temperature, is thus used by geologists as a geochronometer.
Ti concentration profiles, generally interpreted as resulting partly from crystallization and partly from diffusion, are now commonly analysed to understand a wide range of geological phenomena. This technique has allowed, for instance, to estimate the time required for the formation of porphyry ore deposits (which provide, among others, the “ancient marbles”) and to date metamorphic events. It also makes it possible to determine how long and at what temperatures quartz crystallized before a volcanic eruption, during its stay in the magma of the shallow crust.
Jollands and colleagues’ results are striking: the diffusion of Ti would be two to three times slower than previously reported. These new Ti-in-quartz measurements may seem surprising, but they do reconcile the time scales deduced from Ti diffusion with those determined using radioisotopes and other diffusion timers. By revisiting this technique, the authors have thus helped to establish a theory consistent with all existing studies.
Along with other studies by Dr. Jollands, this latter work provides the community with an arsenal of tools to constrain the time scale of geological processes: from mantle convection and melting to magma migration and cooling, through metamorphic reactions and orogenesis. This work has a direct impact on decoding the thermal history of quartz-rich magmas, in particular the pre-eruptive history of major explosive silicic eruptions.
After his stay at ISTE in Othmar Müntener’s team, Michael Jollands is now pursuing his work on the chemistry and physics of crystals and their application to our understanding of time scales at Columbia University (New York), supported by a grant from the Swiss National Science Foundation (SNSF).
Could palaeoclimatology– the study of past climates based on sedimentary records – provide crucial tools to test our predictive models of climate change?The new SPARK project“More uncertainties for more certainty: using uncertainties to connect fossil pollen records in space and time and better reconstruct past climate dynamics” addresses this challenge.
Manuel Chevalier and Fabio Oriani
Manuel Chevalier, who conceived the project, explains his motivations and goals. At Institute of Earth Surface Dynamics (IDYST), Fabio Oriani will be in charge of developing the project.
What is the main objective of your Spark project?
MC: Our goal is to reconstruct past climate variability. To do this, we will develop an unconventional method of analysing fossil pollen. The first analyses of this type date back to the early 1970s. And while the analysis methods have largely evolved since then, the conceptual approach to climate reconstruction has not changed: each record (even each pollen sample!) is considered independently of the others. The so-called “point-based” reconstructions produced are generally associated with the location where the sediments were collected. Yet, fossil pollen samples do not provide a single, accurate record, like a thermometer or rain gauge in your garden. Fossil pollen samples are a record of plant biodiversity and dynamics over a certain time period and region – specifically the entire region from which the pollen grains observed in the sediments may have originated – and cannot be handled independently.
The central objective of our Spark project is therefore to develop a statistical analysis model that takes these spatial characteristics (the “pollen catchment” of each record) into account and uses them appropriately. In this way, we will produce spatialised climate reconstructions from point-based fossil pollen records.
The Spark scheme supports original, high-impact projects. In what way does your project have these qualities?
MC: Integrating spatial and temporal information from pollen records into climate reconstruction is the central innovation of this project. This approach definitely goes against the trend of the last half-century.
Classical analysis methods tend to minimise these spatiotemporal effects. On the contrary, here, we use them and try to extract as much information as possible. In addition to producing a model closer to reality, this approach will allow us to “connect” the reconstructions to each other. When their catchment overlap, we will create the first continuous and spatialised climate reconstructions, and thus, the first gap-free, large-scale reconstructions.
Once the model is developed, the mid-term objective is to create a new generation of more robust palaeoclimate reconstructions around the world. This will help us improve our understanding of past climate dynamics and thus better anticipate the climate changes that await us in the coming decades.
What will be the main challenge and what are your key strengths to face it?
MC: This project is complex for many reasons. The main challenge will probably be to define a model that properly considers the spatial characteristics of the pollen records. We will have to find a good balance between a too high complexity – that would make our method not very generalisable (and possibly too greedy in computation time) – and a too low complexity – that would not enable the conceptual leap from point-based reconstruction to spatialised reconstruction.
Fabio and I will attack the problem with different but complementary skills, which should allow us to find the right formula. Fabio has a good knowledge of spatial modelling methods, which will allow us to develop an advanced statistical approach. On my side, my experience with point-based climate reconstructions and pollen data will allow us to structure the a priori information to inform the models and ensure that the results are consistent from a palaeoenvironmental point of view.
Existing pollen records around the world (left) and the climate reconstructions derived from them (right) are very heterogeneously distributed among different regions. Our project will produce reconstructions in these underrepresented regions, with an initial focus on Africa and South America (green).
How did the project emerge?
MC: The first time I had this idea – or at least one version of it – was a few years ago. I was looking at a map of all the fossil pollen records in Europe in order to make reconstructions. The most obvious observation was that some areas had a rather high density of points and others were fairly sparse. The implication was that we had to find a way to “create information” where there was none in order to produce homogeneous reconstructions in my study area.
One solution is to collect sediment samples in under-sampled regions, and thus produce these missing data… But when working on a European scale, as is the case for this project, the logistics are costly in time, money and in personnel!
An alternative approach is to maximise the potential of what is already available and work on modelling. The advantage of developing new methodologies is that they can produce results much more quickly and, perhaps more importantly, they can be used in other regions than Europe and have a much broader impact.
How will you make sure that your reconstructions in the regions without data are correct?
MC: We will have several options to check our climate predictions. In particular, the first step of this project will be entirely dedicated to the analysis of modern pollen records. The advantage of such modern samples is that the associated climate is known. As such, we will be able to compare our reconstructions with the true climate. The same logic will apply in the regions without data. By using our spatial model with modern data, we will be able to assess the accuracy of our reconstructions in such regions. This approach will also allow us to test which modelling options can produce the best possible reconstructions. Eventually, these results will give us a degree of confidence in our reconstructions of past climates.
Why is IDYST the right place for your project?
MC: Although the study of pollen fossils and the associated climatic reconstitution is not a research axis developed at IDYST, the heart of this project will actually be very technical. Therefore, it is important that we are in a structure where we can find an adapted support. I naturally approached Prof. Mariéthoz to propose him to host us in the GAIA team. His expertise in the development of stochastic methods to characterise the spatial and temporal variability of natural systems is an asset for the project. Fabio and I have been working at IDYST for several years now and we know how the institute works. No doubt that it is an excellent place to do this project. From a technical point of view, the department also provides us with the computational resources needed to calibrate complex statistical models and implement big data strategies.
Why is this project important to you?
MC: For several reasons. First of all, it is the first time I carry out a project with my own funds and it is a great pride for me to conduct my own research. This project will allow me to develop and test a unique model of spatialised reconstructions under different conditions in order to assess the conditions in which it performs best.
More generally, this project represents for me the first stone of a broader research objective that I want to develop over the next few years. One of my research axes is to reconstruct the history of climate in regions where it is generally missing. In particular, the tropical regions of Africa and South America are largely understudied, despite their importance in regulating the global climate. Robustly describing the palaeoclimate will have a significant impact on our understanding of tropical climate dynamics, and by extension global climate.
Our reconstructions will also be a test of current predictive models, which attempt to estimate climate change in the coming years and decades. We will be able to compare our palaeo-climate simulations with these predictive models on a large scale. Identifying where and when the fossil record and predictive models agree, and where they don’t, will highlight the strengths and weaknesses of these models and, ultimately, allow us to refine our ability to better predict future climate change.
With his new European project DISCO2STORE “Discontinuities in CO2 Storage Reservoirs”, Dr. Santiago Solazzi is leading the UNIL participation in a far-reaching network. This 4-year project starting in February 2021 aims at using geophysical techniques to make CO2 storage in geological reservoirs safer and viable as a long-term alternative. Prof. Klaus Holliger and Dr. Nicolás Barbosa from Institute of Earth Sciences are also actively involved in this project.
What is a Marie Curie RISE project?
Research and Innovation Staff Exchange (RISE) is one of the European Marie Curie Actions designed to generate international collaborations between academia and enterprises, to stimulate knowledge and ideas sharing from research to market (and vice versa) by the exchange of staff. The idea behind these exchanges: to promote creativity and entrepreneurship, helping to turn ideas into innovative products or services. This transfer of knowledge is necessary to address the world’s challenges, amongst which, climate change is arguably one of the most prominent.
What is the main goal of DISCO2STORE?
As we are all aware, every year, billions of tons of CO2 are produced as a consequence of human activity. This enormous amount of CO2 is mainly released into the atmosphere, thus increasing the natural greenhouse effect and, consequently, contributing to global warming. Underground storage of CO2 is an immediate option to reduce the amount of this greenhouse gas released into the atmosphere.
In simple words, CO2 storage and sequestration operations propose to inject CO2 back into the earth, into geological reservoirs that contain salty water (thousands of meters below the ground). Naturally, if we wish to develop and apply this technology in more and more places around the world, we need to be able to assure the permanence of CO2 in the underground. This task can only be done through a deep understanding of the geological reservoir and the development of methodologies to accurately monitor CO2 movements and volume estimations. In these operations, the injected CO2 is trapped in the formation through various processes, but generally we need a caprock, that is, a relative impermeable rock that forms a barrier above the reservoir rock so that fluids cannot flow back to the surface. We know that the main risks of leaks are associated with discontinuities in the reservoir or caprock, like the presence of faults and fractures. We aim to develop new techniques to identify mechanical discontinuities in the subsurface, characterize them, and assess their impact in CO2 storage. As we aim to study discontinuities in CO2 storage reservoirs, the project is called DISCO2STORE, which gives the project a festive spirit if you ask me.
How did this RISE project emerge?
This project started by a set of conversations between researchers about discontinuities in reservoirs. The major questions that the DISCO2STORE project aims to tackle require an intersectoral approach, and the use of different laboratories, computational facilities, and knowhow from diverse groups. Marie Curie RISE Action offers this possibility of building paths to create new networks and innovative research training for young scientists.
What are the main actors involved and what will they bring to the project?
Public and private Research and Development institutions are the main actors involved in the project. As I see it, Academia is mainly focused on creating new knowledge, that is, a better understanding of the world. Private companies are mainly concerned with solving challenging problems and creating new applications, using leading edge technology. We need both of them to advance and solve nowadays increasingly complex challenges.
DISCO2STORE participants around the world, mainly located in Europe and South America.
As an example, our group at the Institute of Earth Sciences is trying to better understand how to detect fractures and fluid content in rocks using seismic waves. That is, we send waves throughout the rock and then interpret the information contained in reflections and refractions (like a medical eco-Doppler, but in other scales and frequencies). This method has the advantage of being non-invasive: we are not drilling to obtain the information. Detecting fractured regions of the geologic reservoir where CO2 is going to be stored is important, as fractures affect permeability.
We will try to verify some interesting theories that may permit detecting rather small fractures, which are below the resolution of the seismic waves. This is like saying that one could obtain information from a picture of features that are smaller than the image’s pixel. That is rather awesome! This work will be the mission of our group at UNIL, CNEA and Y-TEC (Argentina) and SINTEF (Norway), private and public Research and Development institutions. This is just an example of one of the works that will take place in this RISE project, of course. We are quite a large number of institutions and researchers working together in these problems, from different angles.
What will be the main challenge of this project and what are your assets to overcome it?
Our challenge is to better understand how to use geophysical and geological information to make CO2 storage safer and viable as a long-term alternative. This can be done by developing strategies to better characterize the formations prior to the injection operations or by providing means to better monitor the evolution of the fluids.
Diagrams showing CO2 storage in a deep salty aquifer, with its caprock preventing fluids flowing back to the surface from the reservoir rock. Figure taken from Bentham & Kirby (CO2 storage in saline aquifers. Oil & gas science and technology, 60(3), 559-567. 2005 10.2516/ogst:2005038).
However, on the personal level, I think the main challenge is to be able to go outside the comfort zone, and to succeed in bringing the numerical models to the laboratory, from academia to industry, and use this inter fertilization of ideas for developing a new understanding of the processes. Building these bridges has been a long-standing motivation for me, and the knowledge and experience acquired during my PhD and postdoc are certainly important assets. However, I would argue that my most important asset is our research group, that is, the people I am working with in this project. Science is a collective construction, and Marie Curie RISE projects are based on this premise.
Why is this project important to you?
It is a great opportunity to try to answer some of the questions I’ve always had about seismic detection of fractures and fluids. We are ambitious with the goals, and this is rather challenging but also deeply motivating. As an example, we are planning on printing 3D samples that mimic fractured rocks here at UNIL and taking them to Norway to measure the mechanical properties. In this process, scientists from Argentina would join to perform measurements and to learn how to use the measuring device, with the idea to replicate the apparatus in their facilities. I will be leading a significant part of the research, mainly the seismic characterization part, and managing a project like this is a deeply formative task. Least but not last, we wish to forge new and long-lasting links between UNIL and other institutions.
Nicolas Barbosa has started in November 2020 an SNF SPARKproject entitled “Borehole-based fracture unclogging experiment: bridging the gap between laboratory- and field-scale evidence”. This project emerged as a result of two research experiences. First, a PhD with Prof. Klaus Holliger, during which Nicolas Barbosa studied how seismic waves are affected by the presence of fractures and fracture networks. Then a first postdoc with Prof. Matteo Lupi at the University of Geneva, where he explored whether and how low-amplitude seismic waves can alter the properties of a fractured medium.
Inside the underground laboratory that hosts the experiments, the Bedretto Underground Laboratory for Geosciences (BULG)[AD1] . Dr. Barbosa’s research objective fits well into the scope of other ongoing BULG projects, which will not only facilitate the experimental procedures, but will also lead to valuable cross-fertilizations.
What is the main goal of your Spark project?
Understanding an important and ubiquitous, yet largely enigmatic, phenomenon: “fracture unclogging”. It manifests itself in major hydrogeological changes, such as unexpected variations in groundwater levels or spring flows. In addition, it seems that “fracture unclogging” may act as a trigger for volcanic or seismic activity. What could cause this phenomenon? Today, the most viable hypothesis is that propagation of seismic waves induces relatively weak changes in pore pressure, which could lead to the mobilization of colloids and fines that obstruct strategic parts of fluid pathways. My goal is to test this hypothesis – so far only supported by small-scale laboratory experiments – through well-controlled field experiments. I also plan to develop a realistic computational model, to simulate these observations and, thus, to improve our understanding of the governing physical processes.
Le Laboratoire souterrain de géosciences de Bedretto (BULG) se trouve à 1,5 km sous la surface, au milieu d’un tunnel de 5,2 km de long qui relie le Tessin au tunnel de la Furka. Le BULG accueille des projets liés à l’utilisation innovante et durable de l’énergie géothermique. Un accent particulier est mis sur la réduction des risques sismiques associés à la stimulation hydraulique de ces réservoirs. Le BULG est exploité par l’ETH Zürich et offre un environnement unique pour explorer les effets de déblocage des fractures à l’échelle mésoscopique dans des conditions expérimentales exceptionnellement bien contrôlées. (Crédit: Marian Hertrich, manager de BULG).
Why is this project important to you?
Arguably, the most defining moment for a young scientist is when he/she can develop and manage the first project independently. Thanks to the SPARK program, I have this opportunity a few years earlier than is commonly the case in our academic system. That said, I am fully aware of the fact that, ultimately, the success of my project hinges on a wide range of collaborations with other scientists and research groups. Indeed, the associated “creative combustion” is, together with the scientific independence and the passion to address an unresolved problem, a key motivational driver for me.
Spark’s vocation is to support original, unconventional and high-impact projects. In what way does your project have these attributes?
Unravelling the physics governing “fracture unclogging” is not only a formidable scientific challenge. It can also lead to a number of potentially important practical applications. Amongst the latter, are the “soft” (that is, aseismic) stimulation of hydrocarbon and geothermal reservoirs to increase their energy production, as well as an improved risk assessment for various natural hazards, such as volcanic eruptions or earthquakes. So far, the only attempts to reproduce this process were performed on centimetre-scale rock samples under highly idealized laboratory conditions. At present, it is unknown how the evidence from these microscale experiment can be transferred over multiple orders-of-magnitude to the field scale, i.e. on a scale at least 100 000 larger, with all the complexities and unknowns that this implies. My idea is to perform mesoscale experiments (between cm and km) under the well-controlled conditions of the Bedretto Underground Laboratory. Specifically, I plan to use a fluid pressure oscillation approach analogous to that in the preceding laboratory experiments and various geophysical techniques for non-invasive monitoring.
Why did you choose the FGSE and ISTE to carry out your project?
I really enjoyed my time as a PhD student at ISTE. During my postdoc, I continued to collaborate with Prof. Holliger’s research group. In addition to a shared scientific focus, it has the required technical resources and has previously worked in the BULG and, thus, pertinent knowledge of the facility and people involved. This significantly facilitated the development and planning of my project. Since the beginning, I have received the full support from ISTE and the FGSE to host my project. The project has recently received additional financial support from the FGSE via the Matterhorn Grants program, for which I am also very grateful. This will permit the drilling of additional short boreholes in which geophysical instruments will be installed for continuously monitoring the hydraulic experiment.
The invasion of land by animals, followed by the establishment of complex continental ecosystems, is a critical event in the history of life on our planet. Nonetheless, little is known about most of the pivotal morphological and physiological adaptations imposed by the water-to-land transition, and particularly air-breathing, because the fossil record for early terrestrial animals is extremely scarce. This is particularly true for myriapods, a large group of terrestrial arthropods including centipedes and millipedes, for which almost no record exists of their aquatic to terrestrial evolution.
In an article published in the Royal Society Open Science journal, Pierre Gueriau, post-doctoral fellow at ISTE, and his international team enlighten us on this subject by describing a unique fossil dating from the Upper Devonian (370 million years ago). Discovered in the 1970s in Belgium by Professor Édouard Poty during a field camp, and named Ericixerxes potii, or “Poty’s hedgehog king” in honor of its discoverer and in reference to its long and large spines (‘ericius’ designating the hedgehog in Latin), this fossil recently rediscovered at the bottom of a drawer is a strange arthropod belonging to the group of euthycarcinoids.
Reconstruction of Ericixerxes potii by Christian McCall.
Euthycarcinoids are rare fossil arthropods that disappeared during the Triassic, some 250 million years ago. They are as fascinating as they are enigmatic: fascinating because they are considered to be the first animals capable of (at least brief) incursions on land, as early as the Cambrian some 500 million years ago! And enigmatic because for a long time palaeontologists had no idea of their precise position in the family tree of arthropods… until they were finally identified this year as the aquatic ancestors of myriapods.
With only a single specimen of this new fossil at its disposal, the team used innovative major-to-trace elemental X-ray fluorescence mapping at the Stanford synchrotron to extract as much information as possible from this arthropod about 10 cm long. The distribution of certain metals and sulphur revealed hitherto invisible morphological details: arsenic and copper uncover a pair of chambers most likely involved in subaerial respiration that clearly differs from the tracheal system of modern myriapods, and sulphur unveil shallow-water evaporation structures.
Photograph of the fossil and maps of arsenic (As), revealing a pair of chambers on the second post-abdominal segment, and sulfur (S), unveiling shallow-water evaporation stains. The colour scale goes from white (low abundance) to black (high abundance).
This new information provides strong support for an amphibious lifestyle in euthycarcinoids and indicates that different respiratory strategies have been used during the marine-to-terrestrial transition in the myriapod lineage, later replaced by tracheal systems.
Pierre Gueriau and his colleagues also emphasize the significance of the novel methodological approach used in this work. While X-ray micro-computed tomography is now regularly used to virtually extract hidden internal information in 3D-preserved fossils, it often fails to reveal hidden anatomies in flat fossils such as their specimen of Ericixerxes potii. This study demonstrates, for the first time, the potential of synchrotron X-ray fluorescence mapping for the visualization of new characters in fossil arthropods. This method, so far essentially applied to fossil vertebrates, has potential applications in all fields of palaeontology and provides a new way of extracting anatomical information from a wide range of compressed fossils.
Thanks to a novel SNF Project funding, Professeur Othmar Müntener (ISTE) will address major unknowns in the role of phosphorusin the shallow crust.
Phosphorus is one of the essential and limiting ingredients for living organisms. Understanding how phosphorus is stored in the continental crust and, in particular, how phosphorus is distributed in silicates is fundamental to estimating how quickly it would be available to organisms. This project proposes to use field and laboratory studies to understand the history of the continental crust.
Why is this project important to you?
The new SNF project is embedded in one of my major research interests: How does continental crust form and evolve? The new project circles around phosphorus (P) in minerals that are important rock clocks: garnet and feldspar. Phosphorus is one of the slowest diffusing elements in these minerals and has therefore the potential to track complicated geological histories.
We are hoping to better quantify cooling histories of granitic rocks in the upper crust by investigating in detail the phosphorus and other trace element distribution in feldspar. Maybe we will also be able to track the growth history, together with other tracers (proxies) such as Barium, Titanium, and Strontium. Overall, we will learn more about rates of geological processes related to the growth and modification of the continental crust.
Studying the traces of chemical elements will ultimately enable us to understand the history of the Earth crust. For example, Barium traces growth zones in k-feldspar from plutonic rocks of the Sierra Nevada (US), in an image from the FEG-EPMA – field emission electron probe micro-analysis – of UNIL (sample kindly provided by T. Sisson)
What has led you to address these issues?
Since my arrival à l’ISTE, one aspect has been the absolute dating of minerals by in-situ Laser ablation ICP-MS (induced coupled plasma – mass spectrometry), a powerful analytical technology that enables highly sensitive elemental and isotopic analyses, directly on solid mineral samples that contain Uranuim, Thorium and Lead. But these age determinations come along with errors, so that individual processes in igneous rocks are in the same age range, given the error margin.
Over the last years, together with a group of talented PhD students and postdocs, and the excellent scientific staff, we worked on the distribution of trace elements – whose concentration is very low – in minerals. These elements have the potential to preserve diffusion profiles, from which timescales of geological processes can be calculated, independent of the absolute age. By studying natural diffusion profiles combined with experimental data, we hope to shed new light on the timescales of magmatic processes in plutonic and volcanic rocks.
What main challenges need to be overcome?
There are two principal challenges. Finding the right samples, where nature has left some traces that can be studied and may provide answers to our questions. And finding the key parameters that may control the governing physical and chemical processes. Bridging the scales between laboratory and natural data is then one of the major issues. This is what we hope to achieve in this project.
What are your expectations from your research?
To develop tools or solutions to establish at what time scales magmatic rocks assemble. Ultimately, advance our understanding of the inner workings of magmatic systems and how they contribute to the formation and evolution of the Earth crust.
The FGSE is pleased to welcome since April 2020 Virginia Ruiz-Villanueva, recipient of an Eccellenza scholarship. She will be interested in the dynamics of rivers and the particularly little-known role of the woods carried there.
Virginia Ruiz Villanueva, Institute of Earth Surface Dynamics (IDYST)
What is the main motivation of your Eccellenza project?
In order to preserve and restore healthy and dynamic rivers, while mitigating potential flood risks, I want to better understand the feedbacks between flow-sediment-wood. As a geomorphologist, I am indeed interested in the physical processes that shape the Earth’s surface and interplay with us, humans. And as a river geomorphologist, I focus on the processes that control the shape and function of rivers.
The importance for rivers of downed trees, trunks, branches and rootwads laying on the river – the so-called instream large wood – is still overlooked. Classically, the physical conceptualisation of rivers focuses mostly on the interactions between water and sediment. However, by interacting with the flow and sediments, the instream wood sustains the physical and ecological integrity of the river, in other words: its health. On the other hand, large quantities of wood transported during floods can constitute a danger. The accumulation of wood in infrastructure such as bridges, among others, might be a major risk. The health of a river thus depends on the flow, sedimentation and wood regimes. I am particularly concerned to assess the latter, which is rarely recognised.
Here, you can see a wood accumulation in a stream, in Vallon de Nant (Vaud). This is a nice example of how instream wood influences river processes and forms. Wood enhances river physical complexity and improves habitat diversity, and thus also biodiversity in the broadest sense. The wood accumulates and forms a step which creates a backwater, dissipates flow energy, lowers velocity, boosts sediment deposition upstream and scouring downstream with the formation of a pool.
What questions you will tackle for next years at the FGSE?
My SNSF Eccellenza Project “Towards a new understanding of fluvial ecosystems: integrating wood regime across multiple scales” focuses on integrating the instream wood regime across multiple disciplines and spatial and temporal scale.
With my team, we will advance wood supply modelling by developing probabilistic models and describe for the first time the wood cascade. To infer where the stored instream wood in rivers comes from, we will combine dendrochemistry and fingerprinting techniques. The ambition is to establish the first Swiss instream wood dynamics observatory and monitor wood motion in several alpine rivers. Among others, this will allow to quantify how much and for how long wood is stored in alpine rivers, and the links between the neighbour forest and the characteristics of the stored instream wood. We will ultimately develop guidelines on the use of natural instream wood for river restoration.
Why have you chosen the FGSE to carry out your project?
For understanding Earth surface processes using a multidisciplinary approach, FGSE and IDYST were the perfect fit for me and my team. With an outstanding team of earth and environmental scientists working on similar topics, but none on wood in rivers, and state-of-the-art facilities, IDYST offers us a great working environment. The project will benefit from the strong collaborative interactions among all groups, especially regarding the analysis of geomorphic processes, the use of remote sensing and Drones, the development of isotope and elemental geochemistry, and the ecology. We hope to strengthen the existing linkages between the groups, becoming an integral part of the Institute’s activities. Despite the difficulties of launching the project during a pandemic (I started in April 2020), FGSE´s welcome has been excellent, and we are already perfectly integrating within the institute.
A word about your new team?
Thanks to the SNSF Eccellenza Professorial Fellowship, I am building the River Ecosystems Research Group (RivES) at IDYST. The team will consist of three PhD students, one research assistant and one Post-doc. I believe the best way to frame and implement our project is building an interdisciplinary team, to draw on knowledge from different disciplines. Thus, the team members have a very varied background, such as forest and environmental engineering, geomorphology, geology, biology or ecology.
Leanne Phelps left Lausanne for Madagascar where she launched her project « Reconstructing the Holocene savannas of Madagascar: implications for long-term disturbance dynamics and modern human land use » thanks to an Early-Postdoc-Mobility grant.
Leanne explains how her desire to understand human land use and sustainable management issues emerged. After having simultaneously carried out the end of her PhD and set up her project, she aims to decipher the role that human land use plays in changing Malagasy savannas. Her first field trips reinforce her hope of reconciling academic research with the search for practical solutions for field actors.
How did this project of mobility come about?
The idea for my Early Postdoc.Mobility was born at an international conference. There was one scientist in particular whose work I knew could expand my research experience in a very beneficial way… so I sat down with her, and within an hour or so we came up with an exciting preliminary idea for a postdoc project! In the following months I did a lot of reading, reaching out to relevant experts whose work I admired, and honing the project proposal.
What was decisive in the preparation of the application?
The application process for the Early Postdoc.Mobility requires a lot of time and attention. For me, this included copious preliminary investigations and reaching out to a number of experts. All this in a very short period of time, and at the same time as the completion and submission of my PhD thesis. Combined, I found these tasks difficult to accomplish! I was lucky enough to find supportive hosts who are as keen to work with me as I am with them. Their support was essential to put together a successful proposal. This was an invaluable resource for me during the write-up period.
Your project has an important applied part for land management. Can academic research contribute to tackling environmental issues?
It’s very important to me that the research I carry out addresses practical and relevant land management issues. Just a few years ago I was quite sceptical about whether formalized research could really address these issues in an effective manner. However, it became increasingly clear during my PhD that research is ideally suited to address practical issues. So long as it’s designed with them in mind. This is what I wished to do for this first postdoc: to place practical questions at the core of the research aims and plan, and to seek collaborators who have this vision.
How are the first field trips shaping up?
My postdoc project (formally) started about a month ago (Nov 2019) in Madagascar. I just conducted my first field trip in tandem with a group of conservationists and really jump-started my understanding of changes in Malagasy vegetation and the role of human land use. This kind of tandem seems to have two primary benefits (so far): my research is more likely to stay rooted in practical management issues pertaining to both local communities and conservation efforts; and we are able to contribute to local capacity building along the way. Of course, this is only the beginning. The most important part will be to ensure that, in addition to the scientific community, our findings will be effectively communicated and discussed with relevant stakeholders: the local communities, the conservation associations, the governmental authorities… This will require a variety of efforts, but I am confident, given the project’s wide net of collaborators and connections.
Advice for future researchers in Mobility?
Develop a project that really addresses a question you’re invested and interested in, and seek out core collaborators that have the potential to dramatically expand your skill set and network (…and start planning as early as possible!). In the year leading up to the deadline for the Early Postdoc.Mobility I knew that I was interested to apply — especially because of the freedom that it could offer me in addressing my own research topic. But I was unsure whether I should submit a proposal for the upcoming deadline or wait for the next round. Once I had the chance to develop my project in detail, it became clear that I wanted to submit a proposal as soon as possible so that I’d have the chance to apply again if my application was unsuccessful. So, I submitted 3 months before my private defence and submitted the thesis just after submitting this application. I am currently very glad that I went out on a limb and did that.
How do you see the next step after Early-Postdoc-Mobility?
I suspect that the next steps will include an application to the FNS Postdoc Mobility scheme (!) so that I can continue to work on new and relevant aspects of my current project, which I am now very invested in.
Pierre Gueriau has started his one-year SPARK project last December. His objective is to identify remains of ancient biomolecules in enigmatic fossil animals. If successful, the project will permit to classify these singular organisms and better understand the evolution of life on our planet. Dr. Gueriau shares his enthusiasm and experience in writing this new type of somewhat unusual project.
Spark focuses on unconventional projects. How is it different from a conventional research project?
The idea I have in mind for this project was born out of the very recent advent of new methodologies that offer unexpected perspectives in this field. The project is audacious, especially from a methodological point of view. Such analysis, which is in full expansion but also still in development, is very constraining in terms of sample preparation. The heterogeneous and complex « fossil animal » material does not fit at all into the textbook cases…
The potential impact of the results is another important criterion for Spark. What is the main impact of your project?
If successful, this project could represent the first stone of a new paradigm in Paleontology. An innovative alternative to DNA that is not preserved beyond a million years, especially in the early stages of animal life. We are still a long way from this, and in the short term this project will, for sure, provide unprecedented scientific data on the chemistry of emblematic early animal fossils that populated our planet.
Was anonymizing the research plan difficult? What difference does this make in writing compared to a traditional research call?
Anonymization had initially worried me a lot, mainly because there is no mention of the identity of the project’s reviewers: internal commission or external experts? The « world is sometimes small » in disciplines involving the use of fresh methods. But in the end, because of its audacious side, which must be put into context (clearly beyond the work of the applicants alone), and because of its five-page limit, this type of project is easily written in the 3rd person. On the other hand, when in some projects there is a tendency to incorporate as much of one’s own work as possible in order to highlight one’s contribution, in the case of Spark there is another document specifically aimed at justifying the applicants’ ability to carry out the project. In addition, and this should be kept in mind when writing, Spark wishes to promote the idea more than the applicants’ CV.
Why is this project important to you?
Quite frankly, this project means a lot to me. It is the first funding of this magnitude (with a salary) that I have obtained on my own behalf. And from a scientific point of view, it is the first project that (finally 5 years after my PhD!) unifies the different aspects of my thesis, which became serendipitously very bipartite after only a few months… This important step, taken during the writing of this a priori « small » project (since only for one year), allows me today to draw the outlines of my research project in the long term.
Au cœur de la production du cacao, David Amuzu cherche à évaluer la durabilité et ses enjeux au Ghana grâce à son Doc.Mobility « Land Use Transition and Socio-Ecological Outcomes in Asunafo Cocoa Growing Region of Ghana ». David Amuzu, doctorant à l’Institut de géograhie et durabilité, a engagé son projet de mobilité à l’automne 2019. Il nous explique ses motivations et ses espoirs.
Sur la photo, David (au centre, les mains croisées) assiste à un entretien dans le cadre d’un programme de certification du cacao, où l’auditeur externe évalue la durabilité des pratiques de production. Il est très habituel pour David de dialoguer avec les agriculteurs sur le terrain pour comprendre leurs pratiques agricoles et la transformation de l’utilisation des terres : Quelles espèces d’arbres sont utilisées ? Pourquoi certains arbres sont-ils préférés à d’autres ? Pourquoi certains sont-ils maintenus ou éliminés dans les exploitations ?
Propos recueillis par Amélie Dreiss
Je connais bien cette région cacaoyère du sud Ghana où j’ai choisi de mener mon projet. Le Ghana est le second plus grand producteur de cacao du monde. Mais malgré leur énorme contribution à l’économie mondiale, les exploitants restent pauvres ; leurs activités agricoles constituent en outre une menace permanente pour la forêt.
Ma région d’étude a connu une transformation dans son mode de production. Ces transformations agraires vont-elles conduire à un système de production plus durable ? Comment les innovations agronomiques et les pratiques de conservation que j’observe se répandent-elles ? J’espère pouvoir mieux comprendre ces questions suite à mon séjour.
J’ai pris conscience du potentiel de mon travail lors d’un premier séjour de 5 mois. J’ai donc cherché des financements plus longs pour aller au bout de mon projet. En consultation avec mon directeur de thèse, le professeur Christian Kull, j’ai réalisé que la bourse Doc.Mobility était une bonne option. Elle offrait en effet le soutien financier le mieux adapté pour continuer mon projet et le mener à bien. Elle permet également de s’appuyer sur les installations, les connaissances et l’expertise analytique d’autres chercheurs qui entreprennent des recherches similaires en-dehors de la Suisse.
Je suis très heureux de bénéficier de cette bourse qui me donne l’espoir de terminer un doctorat potentiellement de grande qualité. Cette bourse me permet aussi de créer un nouveau réseau universitaire au Royaume-Uni, d’acquérir de l’expérience en matière d’enseignement et de recherche. L’établissement-hôte, l’Université de Lancaster, m’offre une large gamme de possibilités de formations complémentaires. Compte tenu de cette diversité, je suis même face à un dilemme dans le choix des compétences et connaissances qui conviennent le mieux à mon projet de recherche et au développement de ma carrière. Aspirant à devenir un jeune chercheur polyvalent, j’essaie de profiter pleinement de ces possibilités variées pour développer ma carrière académique.
J’encourage vivement les futurs doctorants à se lancer dans une mobilité. Participer à ce programme Doc.Mobility avec un projet bien défini est toujours un plus !
Inigo Irarrazaval has obtained a Doc-Mobility grant for his project « Subglacial systems and ice flow dynamics induced by glacial lakes in Exploradores glacier, Patagonia » which he started last October. He shares here his experience.
Can you say a word about the genesis of your Doc.Mobility project ?
From relatively small alpine glaciers, I switched to the Patagonian Ice Fields. The idea came from the desire to use my early doctoral knowledge to expand my expertise to a different setting. And to complete my thesis with skills that were difficult to develop at UNIL. Before I started my doctorate in mobility, I obtained a one-month grant (Mobility2018 CLS-HSG, Centro Latinoamericano-Suizo of the University of St. Gallen) to conduct a pilot study. The success of this pilot study allowed me to clearly define what objectives I could achieve in one year with Doc.Mobility. The Aysén University team I had met immediately showed interest and supported my project.
What difficulties have you overcome ?
Unlike the Alps, there are still few studies in Patagonia. One of the challenges was to collect and compile the few available observational data. Fieldwork in a remote area where weather forecasts are not accurate poses an additional challenge! Especially for piloting the drone, where windless and dry weather conditions are needed….
What do you think this experience will bring you ?
New skills in glaciology of course (such as photogrammetry, mass balance). Being fully in charge of a project, from proposal to implementation, is also a great experience.
Advice for future PhD students in mobility ?
Plan well ahead and have a plan B and C ready. And try to meet face-to-face with the supervisor abroad before establishing a collaboration.
So how do you see the next step after Doc. Mobility ?
So many questions about glaciers remain unanswered! Research in Patagonia is expanding and I would like to continue my research there as a post-doctoral fellow, based in Chile, Switzerland or elsewhere.
A massive ice fall was observed during a sampling campaign at the Mer de Glace in the Mont Blanc massif. In between 30’000 and 60’000 m2 of ice collapsed from the Charpoua glacier, which is a small temperate glacier in the south-east face of the Aiguille Verte.
A glacier is a perennial system on a human scale, a stock of solid water (snow, firn, ice). It is continually renewed by the combined accumulation (snowfall, snow brought by the wind or avalanches) upstream and ablation (melting) downstream. It flows continuously under the effect of its weight, the upper parts, where the accumulation prevails, towards the lower parts, where the ablation dominates. The altitude at which accumulation equals ablation, where the mass balance between gain and loss is zero, corresponds to the equilibrium line. In the Mont Blanc massif, this line was at an elevation of 2800 m.a.s.l. in between 1995 and 2011. Since that it raised to 3200 m.a.s.l.
For a small and steep glacier like the Charpoua glacier, this change in temperature has strong consequences. The Charpoua glacier is a temperate glacier. It means its base is at 0°C and more, so not frozen to the bedrock. When the temperature are rising, ice at the base melts, the resulting water acts like a lubricant, the basal friction drops and the glacier starts to collapse. According to Ludovic Ravanel (CNRS researcher in Edytem Institute) the recent summer temperature anomalies are not the main drivers. It is more likely caused by the local geography in complex balance between its steep topography, its subglacial hydrology and the strong input of avalanche coming from its right side (South face of the Drus).
There is no known study for this specific glacier. But few publications were made in the Mont Blanc massif, especially on the Mer de Glace, the main glacier flowing downstream of the Charpoua glacier. Since 1993, the Mer de Glace experienced a horizontal retreat of about 700m and lost around 70m of thickness at its terminus (Montenvers train station).
During the 5 min event recorded on Sunday 9th, in between 30000 and 60000 m3 of ice collapse, which represents more than 4% of its total volume. Few blocks start falling, then the big part followed. Later in the afternoon when the subglacier river outflow became important, strong debris flows washed the polish from sediments and ice blocks. These debris flows are strongly erosive and it is easy to understand how the canyon shaped into the moraine downstream was made. Other catastrophic events happened this year in the massif due to the rise of the temperature. In august several hundreds of cubic meter of rock collapsed under the ridge of the Cosmic due to the melting of the permafrost.
This catastrophic evolution of high mountain brings many questions. What is the future of the alpinism regarding the instability of these slopes ? How safe and sustainable hydroelectricity produced into large mountain dams is ? How can we manage the production of so many sediments in our rivers? One thing is sure, the climate change is already happening and our mountains are paying the heavy tribut.
Benjamin Lehmann Doctorant FNS Institut des dynamiques de la surface terrestre
Assessment of rockfall susceptibility is a difficult task because numerous processes contribute to make the rock mass unstable.
The Risk Analysis Group of the Institute of Earth Sciences of the University of Lausanne has been working for several years to improve the forecasting of such events. Since 2010, several PhD students and researchers of the group have worked on rockfalls in Yosemite National Park.
This research, funded by the Swiss National Science Foundation, is performed collaboratively with Dr. Greg M. Stock, Yosemite Park’s geologist of the United States National Park Service (USNPS) and Dr. Brian D. Collins of the Landslide Hazards Program of the U.S. Geological Survey (USGS).
The recent rockfall events (Figure 1) that occurred on the southeast face of El Capitan rock formation caused one fatality and several injuries (refer to the New York Times, the New York Times, the Mercury News and the National Park Service). These rockfall events have been analyzed in detail (Figure 2) by the Risk Analysis Group and in particular by Antoine Guerin, a fifth-year PhD student. Antoine has provided the first estimations of the collapsed volumes (450 m3 and 10’250 m3) by comparing the terrestrial laser scans acquired over several years with new post-event photogrammetric models built with photos taken by Dr. Stock on 27 and 28 September.
Figure 1: Before-after comparison of the 28 September 2017 rockfall event. The top photo shows the scar (bottom center) of the 27 September 2017 rockfall event, as well as the one of 11 June 2014 (details in Figure 2). (Photo credit: U.S. National Park Service)
Figure 2: Location of the scars of the 27-28 September 2017 rockfall events with their associated estimated volumes. Data sources: 2006 & 2010 airborne LiDAR by the National Center for Airborne Laser Mapping (NCALM); 2015 terrestrial LiDAR & 2017 Structure-from-Motion (SfM) models by the Risk Analysis Group; SfM pictures taken by Dr. Stock (credit: U.S. National Park Service).
In Yosemite Valley, Drs. Collins and Stock have shown that thermal forcing and solar radiation play a major role in the destabilization and rupture of large granitic rock slabs (See Collins and Stock, 2016, in Nature Geoscience and this video of exfoliating rock from YouTuber dotysan).
By comparing infrared thermal images and high resolution 3D models, the Risk Analysis Group has shown that the El Capitan rockmass, amongst others, goes through significant deformations because of daily thermal cycles. Such deformation occurs every day and leads to a progressive weakening of the rock that may result with ruptures and collapses similar to the events that occurred last week in the southeast face of El Capitan.
The rapid progression of remote sensing techniques over the past decade has improved not only characterization of rockfalls (in terms of number and volume), but also improved understanding of the mechanisms causing these events. However most of these types of analyses are performed only after an event, and forecasting the precise location of a future rockfall remains a difficult task requiring further investigation. Achieving this would require a detailed knowledge of dimensions of all the fractures cutting the rock mass in order to define rock compartments more susceptible to collapse. The trajectories of the resulting falling blocks would then need to be simulated to produce rockfall hazard maps that could be used for land planning in mountainous areas. This issue of rockfall susceptibility is precisely the topic of a scientific paper to be published this year in the journal Landslides (Matasci et al., 2017).
Collins, B. D., & Stock, G. M. (2016). Rockfall triggering by cyclic thermal stressing of exfoliation fractures. Nature Geoscience, 9(5), 395-400.
Matasci, B., Stock, G. M., Jaboyedoff, M., Carrea, D., Collins, B. D., Guerin, A., Matasci, G., Ravanel, L. (2017). Assessing rockfall susceptibility in steep and overhanging slopes using three-dimensional analysis of failure mechanisms. Landslides.
Gérard Stampfli, geologist and honorary professor at the FGSE, received the prestigious Leopold von Buch Medal (German Geological Society) at the end of 2014 for his lifetime achievement. A look back at an exceptional career.
Presenting Gérard Stampfli, I had the pleasure to collaborate with him during the last 20 years. Trying to understand plate tectonic reconstructions, I had to learn that this is just not “moving basement pieces around the globe”, but to find the geographic coordinates for a past time period, where an assemblage of data and observations would fit best the given geological framework.
Born in Pont-l’Evêque (Calvados, France) on 23. February 1949, Gérard Stampfli obtained in 1973 his master in Earth-Sciences at the Department of Geology and Paleontology, University of Geneva/Switzerland, and concluded his studies in the NE Alborz range (Iran) with his PhD thesis in 1978: Etude géologique générale de l’Elbourz oriental au sud de Gonbad-e-Qabus (Iran NE).
His scientific career, then, led him from 1978 to 1987 to Shell International, where he acquired his wide knowledge and experience as seismic interpreter and basin analyst in the Shell main office, The Hague, and subsequently in Borneo and New Zealand, and continued subsequently in the Shell research centre Rijswijk in charge of the 3D seismic interpretation development, before he became team leader for the Gulf of Suez team in Cairo.
Since 1987, Gérard was nominated Professor at the University of Lausanne, Institute of Geology and Paleontology, in charge of general geology, geodynamics, 3D seismostratigraphy and sequential stratigraphy, basin analysis and dynamics, and post grade courses and field trips on Tethyan geology.
During all these years, Gérard participated and organised many national and international scientific conferences and lectures, acted often as key-note speaker, and was responsible in International Geological projects like IGCP 369 (Peritethys Rift Basins, 1994?1999), the TRANSMED Project IGC 2004, Florence, and ELD, Europrobe project on the dynamics of Europe, 2006.
Gérard, consequently, spent most of his lifetime as a geologist, and mostly together with his PhD-students, to gather in the field evidences for the existence of Tethyan oceans, and specifically for the definition of Palaeotethys and Neotethys. Beginning in Geneva with his PhD in Iran, he already dug out in 1978 convincing evidence of what had to become the first step in defining Palaeotethys.
At present, its existence is not to be demonstrated anymore, and about a dozen of reviewed publications on this subject with numerous field data can no more be discarded nor ignored. The fauna and stratigraphy, the evolution in space and time, the suture with the seamounts, the ophiolites, all presenting evidences for the northern margin of Palaeotethys, the observations covering the areas from China to Thailand, the Himalaya, Afghanistan, Iran, to Turkey, Greece and Italy. Nice evidences of the Palaeotethys’ southern margin were found in the Moroccan Anti-Atlas and Meseta, and will certainly be proven even in Spain.
A new door opened since 1996, when including the evolution of the Gondwana margin in the frame of the Intra-Alpine terrain. The input of new data for the pre-Mesozoic basement during my regular visits at Lausanne resulted in the present-day models on the geodynamic evolution of the Gondwana margin in the frame of its worldwide plate-tectonic situation. I remember well, how all these new data were digested in the working group, and that even my bad understanding as a hard-rock geologist would not hinder Gérard, to repeat patiently, why certain models would not work, and why there were only specific reasons, how to see the plate-tectonic evolution through time. I also learnt, that the so-called “Steinmann trilogy”, the beloved model for the evolution of oceanic crust, had to be replaced by thinking in a multivariate evolution model through time, remaining probably like a 3D-web in Gerard’s mind, I suppose. How to communicate such multivariate knowledge, when we have still difficulties to see such models in two dimensions and on a geographic map ?
It is consequently a great pleasure for me to present Gerard Stampfli as the 2014 recipient of the Leopold von Buch medal. With my congratulations!
