Johnson et al. 2022. Giant impacts and the origin and evolution of continents. ...

• Main Authors: Johnson, Tim, Kirkland, Christopher, Lu, Yongjun, Smithies, Hugh, Brown, Michaeal, Hartnady, Michael
• Format: Dataset
• Language: English
• Published: Interdisciplinary Earth Data Alliance (IEDA) 2022
• Subjects: Regional Continents, Oceans; Archaean, early Earth, giant impacts, oxygen isotopes, Pilbara Craton; Iceland
• Online Access: https://dx.doi.org/10.26022/ieda/112307; https://ecl.earthchem.org/view.php?id=2307

Using the oxygen isotope compositions of dated magmatic zircon, we show that the Pilbara Craton in Western Australia, Earth’s best-preserved Archaean (4.0–2.5 billion years ago; Ga) continental remnant, was built in three stages. Stage 1 zircons (3.6–3.4 Ga) form two age clusters with one-third recording sub-mantle δ18O, indicating crystallization from evolved magmas derived from hydrothermally-altered basaltic crust like that in modern-day Iceland. Stage 2 (3.4–3.0 Ga) zircons mostly have mantle-like δ18O and crystallized from parental magmas formed near the base of the evolving continental nucleus. Stage 3 (<3.0 Ga) zircons have above-mantle δ18O, indicating efficient recycling of supracrustal rocks. ... : Smithies, R. H., Lu, Y., Kirkland, C. L., Johnson, T. E., Champion, D. C., Mole D. R., Martin, L., Jeon, H., Wingate, M. T. D. & Johnson, S. P. (2021), Oxygen isotopes trace the origins of Earth’s earliest continental crust, Nature(592): 70–75. Johnson, T. E., Kirkland, C. L., Lu, Y., Smithies, R. H., Brown, M. & Hartnady, M. (2021), Giant impacts and the origin and evolution of continents, Nature(593): xxx–xxx. ...