Noble Gases from the Planetary Nebula Stage of Stellar Evolution Implanted in Meteoritic

Noble gases from the planetary nebula stage of stellar evolution implanted in meteoritic SiC grains

Primordial Krypton in the Terrestrial Mantle Is Not Solar

Introduction: Noble gases are key tracers for the origin of volatiles in the terrestrial planets and of interaction between mantle reservoirs and the atmosphere. General consensus is that material accreting in the solar nebula and nebula gases from the Sun itself were incorporated into the terrestrial planets, providing a starting point for models of planetary evolution. However, the isotopic s...

Low-pressure adsorption of Ar, Kr, and Xe on carbonaceous materials (kerogen and carbon blacks), ferrihydrite, and montmorillonite: Implications for the trapping of noble gases onto meteoritic matter

Noble gases trapped in meteorites are tightly bound in a carbonaceous carrier labeled “phase Q.” Mechanisms having led to their retention in this phase or in its precursors are poorly understood. To test physical adsorption as a way of retaining noble gases into precursors of meteoritic materials, we have performed adsorption experiments for Ar, Kr, and Xe at low pressures (10 4 mbar to 500 mba...

Late Impacts and the Origins of the Atmospheres on Venus, Earth, and Mars

Introduction. Diverse origins of terrestrial planet atmospheres are inferred from differences in the noble gas abundances and isotope ratios observed on Venus, Earth, and Mars [e.g., 1, 2]. Models for the origin of terrestrial atmospheres typically require an intricate sequence of events, including substantial loss and isotopic fractionation of solar nebula gases, outgassed mantle volatiles, an...

The Accretionary Origin of Noble Gases in the Earth’s Mantle

Introduction: An outstanding problem in the Earth and planetary sciences is the source and mechanism by which the Earth-like planets accreted their highly volatile elements. Unlike highly refractory elements, which preserve close to solar proportions in even quite evolved meteorites and the inner planets, moderately refractory and more volatile elements are depleted relative to the highly refra...