2025 年 35 巻 3 号 p. 135-143
Nitrogen is abundant on the Earth’s surface as it is an essential element of life and occupies 78 vol.% of the Earth’s atmosphere. However, the relative abundance of nitrogen normalized by carbonaceous chondrite in the bulk silicate Earth is depleted compared to other volatile elements. This is the so-called “missing” nitrogen which has been an unraveled mystery in geochemistry and the Earth’s interior is one of the candidates for solving it. In this paper, the behavior of nitrogen in the deep Earth is introduced, mainly about nitrogen differentiation by the core formation, formation of nitrogen reservoir through solidification of the magma ocean, and nitrogen transportation via subducting slabs.
