Isotopic Composition of the Moon and the Lunar Isotopic Crisis
The isotopic compositions of the Earth and the Moon are nearly identical for a variety of elements, while other solar system bodies show considerable variations. The isotopic similarity of the Earth and Moon places, together with the depletion in volatile elements, the density deficit, and the large size of the Moon relative to the Earth, strong observable constraints on lunar formation models. Currently, the paradigm of lunar formation, the Giant Impact model, is going through an “isotopic crisis” because it can only be reconciled with the isotope data when some ad hoc assumptions are made.
Origin of Isotopic Variations
Variations in isotopic composition can be of mass-dependent or mass-independent origin. The two types of isotopic variations are fundamentally different and are used to address different questions. Mass-dependent changes in isotope compositions are due to equilibrium or kinetic reactions that follow mass-dependent laws and can provide evidence for various nebular and...
- Kleine T, Kruijer TS, Sprung P (2014) Lunar 182 W and the age and origin of the Moon. In: Paper presented at the 45th lunar and planetary science conference, The Woodlands, Houston, 2895Google Scholar
- Stevenson DJ, Halliday AN (eds.) (2014) Origin of the Moon: challenges and prospects. In: Papers of a discussion meeting issue organized and edited by David J. Stevenson and Alex N. Halliday. Philosophical Transactions of the Royal Society A, vol 372Google Scholar