The composition of the Earth's atmosphere has evolved over time under the influence of numerous mechanisms such as atmospheric escape, magmatic degassing, biological activity, and geodynamics (crustal growth, subduction), etc. Tracking the evolution of atmospheric composition offers the opportunity to track the geological history of the entire planet. Understanding the factors that control a planet's atmospheric composition is also essential for apprehending the geological history of other planets in our solar system, as well as that of exoplanets.

In this presentation, I will show how paleo-atmospheric archives allow us to track the evolution of the atmosphere's composition from the Archean to the present day. This is the primary objective of the ERC Starting Grant project ATTRACTE. Traditionally used archives present certain disadvantages: the atmospheric signal is often masked by excesses of radiogenic gases produced within the Earth's crust, and the true age of the trapped atmospheric signal is very difficult to determine. I will present how hydrothermal minerals formed in impact craters serve as new, easily datable paleo-atmospheric archives that contain a high-purity atmospheric signal.

The paleo-atmospheric archives, scrutinized through coupled noble gas and nitrogen mass spectrometry, demonstrate for example, using xenon isotope systematics, that hydrogen escape likely played a major role in the emergence of oxidizing conditions at Earth's surface. A recent study puts new constraints on how much xenon had been escaping from the Earth’s atmosphere. The evolution of the isotopic composition of argon traces the global degassing of the Earth over time, rather than the evolution of continental crust volume. Mantle degassing is also recorded by the isotopic composition of atmospheric neon.