The first Al-Cu-alloy-bearing unmelted micrometeorite suggests contributions from the disrupted ureilite protoplanet
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
We report the discovery of Al-Cu-alloys within a coarse-grained micrometeorite from the Congo. Oxygen isotope ratios of the sample are consistent with a CV3 source, similar to the Khatyrka meteorite. The petrology of the micrometeorite is also similar to Khatyrka and testifies to the disequilibrium impact mixing between the CV3 parent body and a differentiated body, which was the source of the Al-Cu-alloys. The oxygen isotope composition, however, suggests either limited mixing with projectile silicates or a differentiated projectile with oxygen isotopes close to the CCAM. The most plausible origin of the Al-Cu-alloys is the desilication of an aluminous igneous protolith by hydrothermal activity under highly reduced conditions. We argue that the ureilite parent body is the most likely source for the projectile owing to its silicic magmatism, late-stage reduction and similar oxygen isotope ratios. Al-Cu-alloys can, thus, be found on the disrupted remnants of such protoplanets.
Date Issued
2025-04-15
Date Acceptance
2025-02-17
Citation
Earth and Planetary Science Letters, 2025, 656
ISSN
0012-821X
Publisher
Elsevier
Journal / Book Title
Earth and Planetary Science Letters
Volume
656
Copyright Statement
© 2025 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
License URL
Subjects
Al-Cu-alloy
CHONDRULES
CV3 chondrite
Geochemistry & Geophysics
HISTORY
IMPACT
Micrometeorite
OXYGEN-ISOTOPE
Physical Sciences
Science & Technology
Ureilite
Publication Status
Published
Article Number
119276
Date Publish Online
2025-02-22