Concept

Hadéen

Publications associées (8)

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

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

An early geodynamo driven by exsolution of mantle components from Earth's core

James Badro

Recent palaeomagnetic observations(1) report the existence of a magnetic field on Earth that is at least 3.45 billion years old. Compositional buoyancy caused by inner-core growth(2) is the primary driver of Earth's present-day geodynamo(3-5), but the inne ...

Nature Publishing Group2016

Diversity in the Archean Biosphere: New Insights from NanoSIMS

Anders Meibom, François Robert

The origin of organic microstructures in the similar to 3 Ga Farrel Quartzite is controversial due to their relatively poor state of preservation, the Archean age of the cherts in which they occur, and the unusual spindle-like morphology of some of the for ...

2010

Proto-Planetary Disk Chemistry Recorded By D-Rich Organic Radicals In Carbonaceous Chondrites

Anders Meibom, François Robert

Insoluble organic matter (IOM) in primitive carbonaceous meteorites has preserved its chemical composition and isotopic heterogeneity since the solar system formed similar to 4.567 billion years ago. We have identified the carrier moieties of isotopically ...

2009

Melting experiments of a chondritic meteorite between 16 and 25 GPa: Implication for Na/K fractionation in a primitive chondritic Earth's mantle

Philippe Gillet

Melting experiments at high-pressure and temperature were conducted at pressures from 16 to 25 GPa using chondritic starting material but with slightly enhanced Na- and K-contents while keeping the chondritic Na/K ratio constant. The experiments revealed t ...

2004

Surface morphology of GaN grown by molecular beam epitaxy

Nicolas Grandjean

The surface morphology of GaN(0001) grown on Si(111) by molecular beam epitaxy using ammonia has been studied by near-field microscopy techniques. Two distinct morphologies are observed, depending on the growth kinetics. When using Ga-rich growth condition ...

2001

Meteorite stranding surfaces and the Greenland icesheet

Anders Meibom

Thirty years of recoveries in East Antarctica have led to significant understanding of the regional characteristics associated with meteorite stranding surfaces. In Antarctica these sites are characterized by patches of snow-free blue ice at high altitude ...

2001

Formation of sugar phosphates under potentially natural conditions

In studies related to the origin of life on Earth, the authors considered the geochem. conditions for the formation of tetrose-, pentose-, and hexose phosphates in the Archean. Some of the reactions depend on bilateral surface active minerals for concn. an ...

1998

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