Publications associées à A deep crust-mantle boundary in the asteroid 4 Vesta

New tools for phase segmentation and denoising of analytical STEM data for enhanced chemical sensitivity, applied to Earth mantle research

This thesis is dedicated to developing innovative methodologies that improve elemental quantification in scanning transmission electron microscopy (STEM) using energy-dispersive X-ray spectroscopy (EDXS). The primary motivation stems from a geochemistry pr ...

EPFL2023

Fluid flow through microcracked and fractured granitic reservoirs

Marie Estelle Solange Violay, Michael Heap, Lucille Jocelyne Nadine Carbillet

The permeability of crustal rocks and rock-masses dictates the efficiency of hydrothermal circulation and therefore the productivity of geothermal resources. In this study, we find by monitoring P-wave velocity that thermal microcracking in Lanhélin granit ...

2023

Southern Hemisphere atmospheric history of carbon monoxide over the late Holocene reconstructed from multiple Antarctic ice archives

Jérôme Chappellaz

Carbon monoxide (CO) is a naturally occurring atmospheric trace gas, a regulated pollutant, and one of the main components determining the oxidative capacity of the atmosphere. Evaluating climate–chemistry models under different conditions than today and c ...

2023

Hot rocks: Constraining the thermal conditions of the Mistastin Lake impact melt deposits using zircon grain microstructures

Cyril Cayron

The production of superheated melt during hypervelocity impact events has been proposed to be a common occurrence on terrestrial planetary bodies. Recent direct evidence of superheated impact melt temperatures exceeding > 2370 degrees C from the Kamestasti ...

ELSEVIER2022

Investigating Magma Ocean Solidification on Earth Through Laser‐Heated Diamond Anvil Cell Experiments

Marco Cantoni, Cécile Hébert, Philippe Gillet, Farhang Nabiei, James Badro, Charles-Edouard Boukaré

We carried out a series of silicate fractional crystallization experiments at lower mantle pressures using the laser-heated diamond anvil cell. Phase relations and the compositional evolution of the cotectic melt and equilibrium solids along the liquid lin ...

2021

Composition and Pressure Effects on Partitioning of Ferrous Iron in Iron-Rich Lower Mantle Heterogeneities

Marco Cantoni, Philippe Gillet, Farhang Nabiei, Susannah McGregor Dorfman, James Badro, Charles-Edouard Boukaré

Both seismic observations of dense low shear velocity regions and models of magma ocean crystallization and mantle dynamics support enrichment of iron in Earth’s lowermost mantle. Physical properties of iron-rich lower mantle heterogeneities in the modern ...

2021

The Effects of Planetary and Stellar Parameters on Brittle Lithospheric Thickness

Marie Estelle Solange Violay, Michael Heap

The thicknesss of the brittle lithosphere—the outer portion of a planetary body that fails via fracturing— plays a key role in the geological processes of that body. The properties of both a planet and its host star can influence that thickness, and the po ...

2021

On the effects of fluid pressure variations on rock-mass and fault mechanical behaviour

Corentin Jean-Marie Rémi Noël

In the past 20 years, the growing interest in deep geo-reservoirs for purposes such as carbon storage, waste water disposal, or geothermal energy exploitation have led to large-volume fluid injections into the upper continental crust. These fluid injection ...

EPFL2021

Blocked radiative heat transport in the hot pyrolitic lower mantle

Farhang Nabiei, James Badro, Hélène Marie Piet

The heat flux across the core-mantle boundary (Q(CMB)) is the key parameter to understand the Earth's thermal history and evolution. Mineralogical constraints of the Q(CMB) require deciphering contributions of the lattice and radiative components to the th ...

ELSEVIER2020

Effects of composition and pressure on electronic states of iron in bridgmanite

Arnaud Magrez, Philippe Gillet, Susannah McGregor Dorfman

Electronic states of iron in the lower mantle's dominant mineral, (Mg,Fe,Al)(Fe,Al,Si)O-3 bridgmanite, control physical properties of the mantle including density, elasticity, and electrical and thermal conductivity. However, the determination of electroni ...

MINERALOGICAL SOC AMER2020

PyFrac: A planar 3D hydraulic fracture simulator

Brice Tanguy Alphonse Lecampion, Haseeb Zia

Fluid driven fractures propagate in the upper earth crust either naturally or in response to engineeredfluid injections. The quantitative prediction of their evolution is critical in order to better understandtheir dynamics as well as to optimize their cre ...

2020

Fault Stability Across the Seismogenic Zone

François Xavier Thibault Passelègue

Across the seismogenic zone, the transition from brittle to plastic deformation corresponds to a semibrittle regime where brittle fracturing and plastic flow coexist at high strength conditions. Thorough experimental investigations on brittle-plastic trans ...

AMER GEOPHYSICAL UNION2020

Propagation of fluid driven fractures in transversely isotropic material

Fatima-Ezzahra Moukhtari

The propagation of fluid driven fractures is used in a number of industrial applications (well stimulation of unconventional reservoirs, development of deep geothermal systems) but also occurs naturally (magmatic dyke intrusion). While the mechanics of hyd ...

EPFL2020

Ab Initio Molecular Dynamics Investigation of Molten Fe-Si-O in Earth's Core

James Badro

Silicon and oxygen are potential light elements in Earth's core because their stronger affinity to metal observed with increasing temperature posits that significant amounts of both can be incorporated into the core. It was proposed that an Fe-Si-O liquid ...

AMER GEOPHYSICAL UNION2019

Shock-produced high-pressure (La, Ce, Th)PO4 polymorph revealed by microstructural phase heritage of monazite

Cyril Cayron

The responses of uranium-bearing accessory minerals to shock metamorphism have received growing interest, because under extreme pressure and temperature conditions, these phases can form unique microstructures and/or polymorphs and their radiometric ages c ...

GEOLOGICAL SOC AMER, INC2019

Variations in elastic and electrical properties of crustal rocks with varying degree of microfracturation

Luis Felipe Orellana Espinoza, Marie Estelle Solange Violay, Lucas Xan Pimienta

This work aims at investigating the effect of varying degrees of microfracturing on the joint elastic and electrical transport properties of rocks. Different crustal rocks were subjected to Thermal Treatment, expected to induce microfracturing, up to diffe ...

2019

Investigating Earth's Formation History Through Copper and Sulfur Metal-Silicate Partitioning During Core-Mantle Differentiation

James Badro

Identifying extant materials that act as compositional proxies for Earth is key to understanding its accretion. Copper and sulfur are both moderately volatile elements; however, they display different geochemical behavior (e.g., phase affinities). Thus, in ...

AMER GEOPHYSICAL UNION2018

From 2D to 3D Characterization of Materials Subjected to Extreme Pressure and Temperature Conditions

Farhang Nabiei

Planetesimal were the first planetary objects to form in the solar system, which later grew to make the proto-planets. Most of these bodies were differentiated as a result of internal heating. Several differentiated bodies have, then, been accreted followi ...

EPFL2017

The importance of mantle wedge heterogeneity to subduction zone magmatism and the origin of EM1

Stéphane Laurent Escrig

The composition of the convecting asthenospheric mantle that feeds the mantle wedge can be investigated via rear-arc lavas that have minimal slab influence. This "ambient mantle wedge" composition (the composition of the wedge prior to the addition of a sl ...

Elsevier2017

Cubic zirconia in >2370◦C impact melt records Earth’s hottest crust

Cyril Cayron

Bolide impacts influence primordial evolution of planetary bodies because they can cause instantaneous melting and vaporization of both crust and impactors. Temperatures reached by impact-generated silicate melts are unknown because meteorite impacts are e ...

Elsevier2017