[PPS10-P18] Hydrogen Reservoirs in Mars as Revealed by SNC Meteorites
キーワード：水素同位体、火星隕石
The isotopic signatures of three hydrogen reservoirs are now identified based on analyses of Martian meteorites, telescopic observations, and Curiosity measurements: primordial water, surface water, and subsurface water (Usui, in press). The primordial water is retained in the mantle and has a D/H ratio similar to those seen in Martian building blocks (Usui et al. 2012). The surface water has been isotopically exchanged with the atmospheric water of which D/H ratio has increased through the planet’s history to reach the present-day mean value of ~5,000‰ (Kurokawa et al. 2014). The subsurface water reservoir has intermediate δD values (~1,000-2,000‰), which are distinct from the low-δD primordial and the high-δD surface water reservoirs. We proposed that the intermediate-δD reservoir represents either hydrated crust and/or ground ice interbedded within sediments (Usui et al. 2015). The hydrated crustal materials and/or ground ice could have acquired its intermediate-δD composition from the ancient surface water reservoir (Usui et al. 2017).
References:
Kurokawa, H. et al. (2014). Evolution of water reservoirs on Mars: Constraints from hydrogen isotopes in martian meteorites. Earth Planet. Sci. Lett. 394, 179-185.
Usui et al. (2012) Origin of water and mantle-crust interactions on Mars inferred from hydrogen isotopes and volatile element abundances of olivine-hosted melt inclusions of primitive shergottites. Earth Planet. Sci. Lett. 357-358, 119-129.
Usui et al. (2015) Meteoritic evidence for a previously unrecognized hydrogen reservoir on Mars. Earth Planet. Sci. Lett. 410, 140-151.
Usui et al. (2017) Hydrogen isotopic constraints on the evolution of surface and subsurface water on Mars. The 48th Lunar Planetary Science Conference, Abstract #1278.
Usui et al. (in press) Hydrogen reservoirs in Mars as revealed by SNC meteorites. Volatiles In The Martian Crust (eds. Filiberoto J. and Schwenzer S. P.), Elsevier B.V.
References:
Kurokawa, H. et al. (2014). Evolution of water reservoirs on Mars: Constraints from hydrogen isotopes in martian meteorites. Earth Planet. Sci. Lett. 394, 179-185.
Usui et al. (2012) Origin of water and mantle-crust interactions on Mars inferred from hydrogen isotopes and volatile element abundances of olivine-hosted melt inclusions of primitive shergottites. Earth Planet. Sci. Lett. 357-358, 119-129.
Usui et al. (2015) Meteoritic evidence for a previously unrecognized hydrogen reservoir on Mars. Earth Planet. Sci. Lett. 410, 140-151.
Usui et al. (2017) Hydrogen isotopic constraints on the evolution of surface and subsurface water on Mars. The 48th Lunar Planetary Science Conference, Abstract #1278.
Usui et al. (in press) Hydrogen reservoirs in Mars as revealed by SNC meteorites. Volatiles In The Martian Crust (eds. Filiberoto J. and Schwenzer S. P.), Elsevier B.V.