Skip to Main content Skip to Navigation
Journal articles

Geochemical Constraints on the Size of the Moon-Forming Giant Impact

Abstract : Recent models involving the Moon-forming giant impact hypothesis have managed to reproduce the striking isotopic similarity between the two bodies, albeit using two extreme models: one involves a high-energy small impactor that makes the Moon out of Earth's proto-mantle; the other supposes a gigantic collision between two half-Earths creating the Earth-Moon system from both bodies. Here we modeled the geochemical influence of the giant impact on Earth's mantle and found that impactors larger than 15% of Earth mass result in mantles always violating the present-day concentrations of four refractory moderately siderophile trace elements (Ni, Co, Cr, and V). In the aftermath of the impact, our models cannot further discriminate between a fully and a partially molten bulk silicate Earth. Then, the preservation of primordial geochemical reservoirs predating the Moon remains the sole argument against a fully molten mantle after the Moon-forming impact.
Complete list of metadata

Cited literature [59 references]  Display  Hide  Download
Contributor : Eva Fareau Connect in order to contact the contributor
Submitted on : Wednesday, April 29, 2020 - 5:57:55 PM
Last modification on : Friday, August 5, 2022 - 12:01:04 PM


Publisher files allowed on an open archive




Hélène Piet, James Badro, Philippe Gillet. Geochemical Constraints on the Size of the Moon-Forming Giant Impact. Geophysical Research Letters, American Geophysical Union, 2017, 44 (23), pp.11,770-11,777. ⟨10.1002/2017GL075225⟩. ⟨insu-02558677⟩



Record views


Files downloads