1. Extraction by grinding

Fluid inclusions are small cavities (0.1 < Ø (μm) < 1,000) present in magmatic, metamorphic or sedimentary rocks that may, depending on the case, have one or more phases (vapor: CO ₂ , H ₂ O, N ₂ , etc. liquid: CO ₂ , H ₂ O, etc.; and solid: NaCl, carbonate, etc.) and may have formed at the same time as the rock (or mineral) (primary inclusion) or after its formation (secondary inclusion). Accessing and analyzing the noble gases trapped in them provides the information needed for a better understanding of fluid circulation in the Earth's crust or at the mantle-crust interface.