Sublithospheric diamond ages and the supercontinent cycle

Suzette Timmerman*, Thomas Stachel, Janne M. Koornneef, Karen V. Smit, Rikke Harlou, Geoff M. Nowell, Andrew R. Thomson, Simon C. Kohn, Joshua H.F.L. Davies, Mandy Y. Krebs, Sarah E.M. Milne, Jeffrey W. Harris, Felix Kaminsky, Dmitry Zedgenizov, Galina Bulanova, Chris B. Smith, Izaac Cabral Neto, Francisco V. Silveira, Antony D. Burnham, Fabrizio NestolaSteven B. Shirey, Michael J. Walter, Andrew Steele

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

2 Citations (Scopus)

Abstract

Subduction related to the ancient supercontinent cycle is poorly constrained by mantle samples. Sublithospheric diamond crystallization records the release of melts from subducting oceanic lithosphere at 300–700 km depths1,2 and is especially suited to tracking the timing and effects of deep mantle processes on supercontinents. Here we show that four isotope systems (Rb–Sr, Sm–Nd, U–Pb and Re–Os) applied to Fe-sulfide and CaSiO3 inclusions within 13 sublithospheric diamonds from Juína (Brazil) and Kankan (Guinea) give broadly overlapping crystallization ages from around 450 to 650 million years ago. The intracratonic location of the diamond deposits on Gondwana and the ages, initial isotopic ratios, and trace element content of the inclusions indicate formation from a peri-Gondwanan subduction system. Preservation of these Neoproterozoic–Palaeozoic sublithospheric diamonds beneath Gondwana until its Cretaceous breakup, coupled with majorite geobarometry3,4, suggests that they accreted to and were retained in the lithospheric keel for more than 300 Myr during supercontinent migration. We propose that this process of lithosphere growth—with diamonds attached to the supercontinent keel by the diapiric uprise of depleted buoyant material and pieces of slab crust—could have enhanced supercontinent stability.

Original languageEnglish
Pages (from-to)752-756
Number of pages5
JournalNature
Volume623
Issue number7988
DOIs
Publication statusPublished - 23 Nov 2023

Bibliographical note

Publisher Copyright:
© 2023, The Author(s).

Structured keywords

  • PetrologyLabs

Fingerprint

Dive into the research topics of 'Sublithospheric diamond ages and the supercontinent cycle'. Together they form a unique fingerprint.

Cite this