Publications associées à Silicate perovskite

First-Principles Thermodynamics of CsSnI3

CsSnI3 is a promising ecofriendly solution for energy harvesting technologies. It exists at room temperature in either a black perovskite polymorph or a yellow 1D double-chain, which irreversibly deteriorates in the air. In this work, we unveil the relativ ...

AMER CHEMICAL SOC2023

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

Hui Chen

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

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

Philippe Gillet, Cécile Hébert, Marco Cantoni, James Badro, Farhang Nabiei, 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

Philippe Gillet, Marco Cantoni, James Badro, Susannah McGregor Dorfman, Farhang Nabiei, 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

In-line electronic and structural characterization of reactively sputtered Cu-Co-Mn black spinel oxides

Andreas Schueler, Anna Krammer, Maxime Lagier

Cu-Co-Mn spinel oxide thin films are deposited by reactive magnetron sputtering. The x-ray diffraction (XRD) spectrum suggests a nanocrystalline spinel film when sputtered at approximate to 465 degrees C. In-line scanning tunneling microscopy confirms nano ...

A V S AMER INST PHYSICS2021

Reply to Comment by Jennings et al. on "Investigating Earth's Formation History Through Copper and Sulfur Metal-Silicate Partitioning During Core-Mantle Differentiation"

James Badro

Recognizing existing materials that can act as proxies for Earth's building blocks, and understanding the accretionary pathway taken during Earth's growth, persist as outstanding issues in need of resolution. In Mahan, Siebert, Blanchard, Badro, et al. (20 ...

AMER GEOPHYSICAL UNION2019

Characterization of Fly Ashes by a Novel Method in the Scanning Electron Microscope

Karen Scrivener, Cyrille Dunant, Mohsen Ben Haha, Pawel Tadeusz Durdzinski

In this paper, we show a new technique to characterize fly ashes using scanning electron microscopy (SEM). Chemical composition of millions of points is measured by SEM-energy dispersive X-ray spectroscopy and plotted in a ternary frequency plot. This new ...

ASTM INTERNATIONAL2019

Magnesium Partitioning Between Earth's Mantle and Core and its Potential to Drive an Early Exsolution Geodynamo

James Badro

Magnesium partitioning between metal and silicate was experimentally investigated between 34 and 138GPa, 3,500 and 5,450K using laser-heated diamond anvil cells. The 22 measurements are combined with previously published data (total of 49 measurements) to ...

AMER GEOPHYSICAL UNION2018

Phase transition processes of olivine in the shocked Martian meteorite Tissint: Clues to origin of ringwoodite-, bridgmanite- and magnesiowilstite-bearing assemblages

Philippe Gillet

Tissint is a heavily shocked olivine-phyric shergottite. We investigated and documented several phase transformations and dissociation phenomena of olivine adjacent to and in many shock-induced melt-pockets of Tissint. Olivine grains entrained in the melt- ...

Elsevier2016

Chemical Characterisation of Deep Earth Reservoirs

Hélène Marie Piet

Seismic imaging of the internal Earth has emphasized the inhomogeneity of its mantle. This interface layer of nearly 3000 km surrounding the central metallic core conducts heat released from the latter, which played a significant role in shaping the actual ...

EPFL2016

Composition dependence of spin transition in (Mg,Fe)SiO3 bridgmanite

Philippe Gillet, James Badro, Susannah McGregor Dorfman

Spin transitions in (Mg,Fe)SiO3 bridgmanite have important implications for the chemistry and dynamics of Earth's lower mantle, but have been complex to characterize in experiments. We examine the spin state of Fe in highly Fe-enriched bridgmanite synthesi ...

Mineralogical Society of America2015

Unique large diamonds in a ureilite from Almahata Sitta 2008 TC3 asteroid

Philippe Gillet

The Almahata Sitta MS-170 ureilite (a piece of a breccia originating from the asteroid, 2008 TC3) consists mainly of olivine, with many diamond and graphite grains existing between the olivine grains. The occurrences of the diamonds are unique; i.e., (i) s ...

Pergamon-Elsevier Science Ltd2015

Composition of the core from gallium metal-silicate partitioning experiments

James Badro

Gallium concentration (normalized to CI chondrites) in the mantle is at the same level as that of lithophile elements with similar volatility, implying that there must be little to no gallium in Earth's core. Metal-silicate partitioning experiments, howeve ...

Elsevier2015

Effect of Fe-enrichment on seismic properties of perovskite and post-perovskite in the deep lower mantle

Susannah McGregor Dorfman

Recent experimental measurements of the equation of state of perovskites and post-perovskites in the (Mg,Fe)SiO3 and (Mg,Fe,Al)(Fe,Al,Si)O-3 systems over a wide range of iron contents are used to constrain the effects of Fe and Al on density and bulk modul ...

Oxford University Press2014

Shock-induced deformation of Shergottites: Shock-pressures and perturbations of magmatic ages on Mars

Philippe Gillet, Pierre Beck

Shergottites and Chassignites practiced major deformation effects whose nature, magnitude and relevance were controversially evaluated and disputatively debated. Our studies of many shocked shergottites present, contrary to numerous previous reports, ample ...

Pergamon-Elsevier Science Ltd2013

Effects of Fe-enrichment on the equation of state and stability of (Mg,Fe)SiO3 perovskite

Susannah McGregor Dorfman

Fe-rich natural orthopyroxenes with compositions of (Mg0.61Fe0.38Ca0.01)SiO3 (Fe#38) and (Mg0.25Fe0.74Ca0.01)SiO3 (Fe#74) were studied at pressures up to 155 GPa and temperatures up to 3000 K. Single-phase orthorhombic GdFeO3-type perovskite was synthesize ...

Elsevier Science Bv2013

Using Silicate Mineral Particles for pH Control during in situ Bioremediation of Chlorinated Ethene Source Zones

Elsa Marina Lacroix

Soil and groundwater pollution by chlorinated solvents such as tricholorethene (TCE) and tetrachloroethene (PCE) is a frequent problem in the industrialized world. Chlorinated solvents, characterized by a low solubility and a density greater than water, fo ...

EPFL2013

Synthesis and equation of state of perovskites in the (Mg, Fe)(3)Al2Si3O12 system to 177 GPa

Susannah McGregor Dorfman

Natural and synthetic pyrope-almandine compositions from 38 to 100 mol% almandine (Alm38-Alm100) were studied by synchrotron X-ray diffraction in the laser-heated diamond anvil cell to 177 GPa. Single-phase orthorhombic GdFeO3-type perovskites were synthes ...

Elsevier Science Bv2012

Evaluation of silicate minerals for pH control during bioremediation: Application to chlorinated solvents

David Andrew Barry, Christof Holliger, Alessandro Brovelli, Elsa Marina Lacroix

Accurate control of groundwater pH is of critical importance for in situ biological treatment of chlorinated solvents. This study evaluated a novel approach for buffering subsurface pH that relies on the use of silicate minerals as a long-term source of al ...

2012

Microstructural development of early age hydration shells around cement grains

Karen Scrivener, Emmanuel Gallucci, Prakash Chandra Mathur

An important microstructural aspect of the early hydration of Portland cement (K) is the formation of a shell of hydration products around cement grains. There is, at present, limited information on the mechanism of formation of the shell and of the chemis ...

Pergamon-Elsevier Science Ltd2010