Evidence of extensive lunar crust formation in impact melt sheets 4,330 Myr ago

Lee Francis White, Ana Černok, James Darling, Martin J. Whitehouse, Katie Joy, C. Cayron, Joseph Nicholas Dunlop, Kimberly Tait, Mahesh Anand

Research output: Contribution to journalArticlepeer-review

93 Downloads (Pure)

Abstract

Accurately constraining the formation and evolution of the lunar magnesian (Mg) suite is key to understanding the earliest periods of magmatic crustal building that followed accretion and primordial differentiation of the Moon. However, the origin and evolution of these unique rocks is highly debated. Here, we report on the microstructural characterisation of a large (~250 μm) baddeleyite (monoclinic-ZrO2) grain in Apollo troctolite 76535 that preserves quantifiable crystallographic relationships indicative of reversion from a precursor cubic-ZrO2 phase. This observation places important constraints on the formation temperature of the grain (> 2300 °C) which endogenic processes alone fail to reconcile. We conclude that the troctolite crystallized directly from a large, differentiated impact melt sheet 4326 ± 14 million years (Myr) ago. These results suggest that impact bombardment would have played a critical role in the evolution of the earliest planetary crusts.
Original languageEnglish
Article number0
Pages (from-to)974-978
Number of pages5
JournalNature Astronomy
Volume4
Issue number10
Early online date11 May 2020
DOIs
Publication statusPublished - 1 Oct 2020

Keywords

  • Moon
  • meteorite
  • Baddeleyite
  • Geochronology
  • meteorite impact
  • Apollo
  • Lunar
  • Microstructure
  • EBSD
  • SIMS
  • geology
  • geological materials
  • RCUK
  • STFC
  • ST/L000776/1
  • ST/P000657/1
  • ST/M001253
  • ST/S000291/1

Fingerprint

Dive into the research topics of 'Evidence of extensive lunar crust formation in impact melt sheets 4,330 Myr ago'. Together they form a unique fingerprint.

Cite this