ERC FUNDED PROJECTS

"The eruption of volcanoes appears one of the most unpredictable phenomena on Earth. Yet the situation is rapidly changing. Quantification of the eruptive record constrains what is possible in a given volcanic system. Timing is the hardest part to quantify. The main process triggering an eruption is the refilling of a sub-volcanic magma chamber by a new magma coming from depth. This process results in magma mixing and provokes a time-dependent diffusion of chemical elements. Understanding the time elapsed from mixing to eruption is fundamental to discerning pre-eruptive behaviour of volcanoes to mitigate the huge impact of volcanic eruptions on society and the environment. The CHRONOS project proposes a new method that will cut the Gordian knot of the presently intractable problem of volcanic eruption timing using a surgical approach integrating textural, geochemical and experimental data on magma mixing. I will use the compositional heterogeneity frozen in time in the rocks the same way a broken clock at a crime scene is used to determine the time of the incident. CHRONOS will aim to: 1) be the first study to reproduce magma mixing, by performing unique experiments constrained by natural data and using natural melts, under controlled rheological and fluid-dynamics conditions; 2) obtain unprecedented high-quality data on the time dependence of chemical exchanges during magma mixing; 3) derive empirical relationships linking the extent of chemical exchanges and the mixing timescales; 4) determine timescales of volcanic eruptions combining natural and experimental data. CHRONOS will open a new window on the physico-chemical processes occurring in the days preceding volcanic eruptions providing unprecedented information to build the first inventory of eruption timescales for planet Earth. If these timescales can be linked with geophysical signals occurring prior to eruptions, this inventory will have an immense value, enabling precise prediction of volcanic eruptions."

1 993 813 €

Start date: 2014-05-01, End date: 2019-04-30

Human activities are altering the global climate system at rates faster than ever recorded in geologic time. Ample observational evidence exists for anthropogenic climate change including measured increased in atmospheric CO2, temperature and sea level rise. Biomass burning causes CO2 emissions of ~50% of those from fossil-fuel combustion and so are highly likely to influence future climate change. However, aerosols continue to be the least understood aspect of the modern climate system and even less is known about their past influence. Anthropogenic aerosols may have altered the global climate system for thousands of years as suggested by comparing late-Holocene greenhouse-gas concentrations to those from previous interglacials. The decrease in the spatial extent of forests beginning ~8000 yrs BP may be related to early agricultural activity including forest clearance through burning which should leave a quantifiable signal in climate proxies. We pioneered a ground-breaking technique for determining a specific molecular marker of biomass burning (levoglucosan) which can record past fire in ice cores and lake sediments. The research incorporates continuous ice and lake core climate records from seven continents with parallel histories of fire regime. These can provide essential insight into the interplay between climate and human activity, especially with the advent of agriculture. Key objectives include: 1) How does biomass burning change through time and space? 2) How do climate parameters respond to or correlate with changes in biomass burning? 3) Did fires increase ~8000 and/or ~5000 years ago? 4) Can natural and anthropogenic fires be differentiated? If so, how do fires and associated climate change ascribed to human activity differ from natural biomass burning?

2 370 767 €

Start date: 2011-07-01, End date: 2016-12-31

Diamonds and their inclusions are the deepest materials originating from the Earth’s interior reaching the surface of our planet. Their study plays a key role in understanding and interpreting the geodynamics, geophysics, petrology, geochemistry and mineralogy of the Earth’s mantle and those processes which governed trough the time the evolution of the Earth. The most abundant mineral inclusions in diamonds are olivines, orthopyroxenes, clinopyroxenes, garnets, spinels, and sulfides. All of these mineral phases have been identified by X-ray diffraction or electron microprobe analysis since the 1950’s almost always after their extraction from the diamonds. However, a non-destructive in-situ investigation of an inclusion in diamond is useful and important because: (a) some mineral inclusions under pressure could have a different crystal structure, and thus different petrologic significance compared to that at ambient pressure; (b) the internal pressure on the inclusion can provide information about the formation pressure of the diamond; (c) the morphology and growth relationships of the inclusion with the host diamond can provide indications about its protogenetic vs. syngenetic and/or epigenetic nature. In this project a new experimental approach, based on X-ray diffraction technique, will be used in order to determine, for the first time, the crystal structure of the inclusions still trapped in their host diamonds allowing to obtain chemical information capable to provide the inclusion remnant pressure and, from this, the pressure of formation of the diamond-inclusion pair. At the same time, our approach will allow to obtain any possible epitaxial relationship between diamond and its inclusions in order to provide strong constraints about the syngenetic or protogenetic nature of minerals included in diamond solving a 50 years old debate. Several geochemical and geodynamical models are based on the assumption of syngenesis but this has yet to be demonstrated.

1 423 464 €

Start date: 2013-01-01, End date: 2018-12-31

Earthquakes represent one of our greatest natural hazards. Even a modest improvement in the ability to forecast devastating events like the 2016 sequence that destroyed the villages of Amatrice and Norcia, Italy would save thousands of lives and billions of euros. Current efforts to forecast earthquakes are hampered by a lack of reliable lab or field observations. Moreover, even when changes in rock properties prior to failure (precursors) have been found, we have not known enough about the physics to rationally extrapolate lab results to tectonic faults and account for tectonic history, local plate motion, hydrogeology, or the local P/T/chemical environment. However, recent advances show: 1) clear and consistent precursors prior to earthquake-like failure in the lab and 2) that lab earthquakes can be predicted using machine learning (ML). These works show that stick-slip failure events –the lab equivalent of earthquakes– are preceded by a cascade of micro-failure events that radiate elastic energy in a manner that foretells catastrophic failure. Remarkably, ML predicts the failure time and in some cases the magnitude of lab earthquakes. Here, I propose to connect these results with field observations and use ML to search for earthquake precursors and build predictive models for tectonic faulting. This proposal will support acquisition and analysis of seismic and geodetic data and construction of new lab equipment to unravel earthquake physics, precursors and forecasts. I will use my background in earthquake source theory, ML, fault rheology, and geodesy to address the physics of earthquake precursors, the conditions under which they can be observed for tectonic faults and the extent to which ML can forecast the spectrum of fault slip modes. My multidisciplinary team will train the next generation of researchers in earthquake science and foster a new level of broad community collaboration.

3 459 750 €

Start date: 2020-01-01, End date: 2024-12-31