Earth’s oldest evolved (felsic) rocks, the 4.02-billion-year-old Idiwhaa gneisses of the Acasta Gneiss Complex, northwest Canada, have compositions that are distinct from the felsic rocks that typify Earth’s ancient continental nuclei, implying that they formed through a different process. Using phase equilibria and trace element modelling, we show that the Idiwhaa gneisses were produced by partial melting of iron-rich hydrated basaltic rocks (amphibolites) at very low pressures, equating to the uppermost ~3 km of a Hadean crust that was dominantly mafic in composition. The heat required for partial melting at such shallow levels is most easily explained through meteorite impacts. Hydrodynamic impact modelling shows not only that this scenario is physically plausible, but also that the region of shallow partial melting appropriate to formation of the Idiwhaa gneisses would have been widespread. Given the predicted high flux of meteorites in the late Hadean, impact melting may have been the predominant mechanism that generated Hadean felsic rocks.
Subscribe to Journal
Get full journal access for 1 year
only $14.08 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Marchi, S. et al. Widespread mixing and burial of Earth’s Hadean crust by asteroid impacts. Nature 511, 578–582 (2014).
Koeberl, C. Impact processes on the early Earth. Elements 2, 211–216 (2006).
O’Neill, C., Marchi, S., Zhang, S. & Bottke, W. Impact-driven subduction on the Hadean Earth. Nat. Geosci. 10, 793–797 (2017).
Van Kranendonk, M. J., Bennett, V. & Smithies, H. R. Earth’s Oldest Rocks Vol. 15 (Elsevier, Amsterdam, 2007).
Wilde, S. A., Valley, J. W., Peck, W. H. & Graham, C. M. Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago. Nature 409, 175–178 (2001).
Mojzsis, S. J., Harrison, T. M. & Pidgeon, R. T. Oxygen-isotope evidence from ancient zircons for liquid water at the Earth’s surface 4,300 Myr ago. Nature 409, 178–181 (2001).
Valley, J. W., Peck, W. H., King, E. M. & Wilde, S. A. A cool early Earth. Geology 30, 351–354 (2002).
Harrison, T. M. et al. Geochemistry: heterogeneous hadean hafnium: evidence of continental crust at 4.4 to 4.5 Ga. Science 310, 1947–1950 (2005).
Harrison, T. M., Schmitt, A. K., McCulloch, M. T. & Lovera, O. M. Early (≥4.5 Ga) formation of terrestrial crust: Lu–Hf, δ18O, and Ti thermometry results for Hadean zircons. Earth. Planet. Sci. Lett. 268, 476–486 (2008).
Iizuka, T. et al. 4.2 Ga zircon xenocryst in an Acasta gneiss from northwestern Canada: evidence for early continental crust. Geology 34, 245–248 (2006).
Reimink, J. R. et al. No evidence for Hadean continental crust within Earth’s oldest evolved rock unit. Nat. Geosci. 9, 777–780 (2016).
Darling, J., Storey, C. & Hawkesworth, C. Impact melt sheet zircons and their implications for the Hadean crust. Geology 37, 927–930 (2009).
O’Neil, J. & Carlson, R. W. Building Archaean cratons from Hadean mafic crust. Science 355, 1199–1202 (2017).
Bowring, S. A. & Williams, I. S. Priscoan (4.00–4.03 Ga) orthogneisses from northwestern Canada. Contrib. Mineral. Petrol. 134, 3–16 (1999).
Stern, R. A. & Bleeker, W. Age of the world’s oldest rocks refined using Canada’s SHRIMP: the Acasta Gneiss Complex, Northwest Territories, Canada. Geosci. Can. 25, 27–31 (1998).
Reimink, J. R., Chacko, T., Stern, R. A. & Heaman, L. M. Earth’s earliest evolved crust generated in an Iceland-like setting. Nat. Geosci. 7, 529–533 (2014).
Reimink, J. R., Chacko, T., Stern, R. A. & Heaman, L. M. The birth of a cratonic nucleus: lithogeochemical evolution of the 4.02–2.94 Ga Acasta Gneiss Complex. Precambr. Res. 281, 453–472 (2016).
Moyen, J. F. The composite Archaean grey gneisses: petrological significance, and evidence for a non-unique tectonic setting for Archaean crustal growth. Lithos 123, 21–36 (2011).
Koshida, K., Ishikawa, A., Iwamori, H. & Komiya, T. Petrology and geochemistry of mafic rocks in the Acasta Gneiss Complex: implications for the oldest mafic rocks and their origin. Precambr. Res. 283, 190–207 (2016).
Iizuka, T., Komiya, T., Rino, S., Maruyama, S. & Hirata, T. Detrital zircon evidence for Hf isotopic evolution of granitoid crust and continental growth. Geochim. Cosmochim. Acta 74, 2450–2472 (2010).
Iizuka, T. et al. Geology and zircon geochronology of the Acasta Gneiss Complex, northwestern Canada: new constraints on its tectonothermal history. Precambr. Res. 153, 179–208 (2007).
Nicholson, H. et al. Geochemical and isotopic evidence for crustal assimilation beneath Krafla, Iceland. J. Petrol. 32, 1005–1020 (1991).
Bindeman, I. et al. Silicic magma petrogenesis in Iceland by remelting of hydrothermally altered crust based on oxygen isotope diversity and disequilibria between zircon and magma with implications for MORB. Terra Nova 24, 227–232 (2012).
Martin, E. & Sigmarsson, O. Thirteen million years of silicic magma production in Iceland: links between petrogenesis and tectonic settings. Lithos 116, 129–144 (2010).
Gibson, R. Impact‐induced melting of Archaean granulites in the Vredefort Dome, South Africa. I: anatexis of metapelitic granulites. J. Metamorph. Geol 20, 57–70 (2002).
Grieve, R. A. Petrology and chemistry of the impact melt at Mistastin Lake crater, Labrador. Geol. Soc. Am. Bull. 86, 1617–1629 (1975).
Vishnevsky, S. & Montanari, A. Popigai impact structure (Arctic Siberia, Russia): geology, petrology, geochemistry, and geochronology of glass-bearing impactites. Geol. Soc. Am. Spec. Pap. 339, 19–60 (1999).
Grieve, R. A., Stoeffler, D. & Deutsch, A. The Sudbury structure: controversial or misunderstood? J. Geophys. Res. Planets 96, 22753–22764 (1991).
Kring, D. A. & Boynton, W. V. Petrogenesis of an augite-bearing melt rock in the Chicxulub structure and its relationship to K/T impact spherules in Haiti. Nature 358, 141–144 (1992).
Pierazzo, E., Vickery, A. & Melosh, H. A reevaluation of impact melt production. Icarus 127, 408–423 (1997).
Green, E. C. R. et al. Activity–composition relations for the calculation of partial melting equilibria in metabasic rocks. J. Metamorph. Geol. 34, 845–869 (2016).
Bédard, J. H. A catalytic delamination-driven model for coupled genesis of Archaean crust and sub-continental lithospheric mantle. Geochim. Cosmochim. Acta 70, 1188–1214 (2006).
Johnson, T. E., Brown, M., Gardiner, N. J., Kirkland, C. L. & Smithies, R. H. Earth’s first stable continents did not form by subduction. Nature 543, 239–242 (2017).
Brown, M. & Johnson, T. Secular change in metamorphism and the onset of global plate tectonics. Am. Mineral. 103, 181–196 (2018).
Hofmeister, A. M. Effect of a Hadean terrestrial magma ocean on crust and mantle evolution. J. Geophys. Res. 88, 4963–4983 (1983).
Amsden, A., Ruppel, H. & Hirt, C. SALE: A Simplified ALE Computer Program For Fluid Flow At All Speeds (US Department of Commerce, National Technical Information Service, 1980).
Carley, T. L. et al. Iceland is not a magmatic analog for the Hadean: evidence from the zircon record. Earth. Planet. Sci. Lett. 405, 85–97 (2014).
Kemp, A. I. S. et al. Hadean crustal evolution revisited: new constraints from Pb–Hf isotope systematics of the Jack Hills zircons. Earth. Planet. Sci. Lett. 296, 45–56 (2010).
Berry, A. J., Danyushevsky, L. V., St C. O’Neill, H., Newville, M. & Sutton, S. R. Oxidation state of iron in komatiitic melt inclusions indicates hot Archaean mantle. Nature 455, 960–963 (2008).
Powell, R. & Holland, T. J. B. An internally consistent dataset with uncertainties and correlations: 3 applications to geobarometry, worked examples and a computer program. J. Metamorph. Geol. 6, 173–204 (1988).
Holland, T. J. B. & Powell, R. An improved and extended internally consistent thermodynamic dataset for phases of petrological interest, involving a new equation of state for solids. J. Metamorph. Geol. 29, 333–383 (2011).
White, R. W., Powell, R., Holland, T. J. B., Johnson, T. E. & Green, E. C. R. New mineral activity–composition relations for thermodynamic calculations in metapelitic systems. J. Metamorph. Geol. 32, 261–286 (2014).
White, R. W., Powell, R. & Clarke, G. L. The interpretation of reaction textures in Fe-rich metapelitic granulites of the Musgrave Block, Central Australia: constraints from mineral equilibria calculations in the system. J. Metamorph. Geol. 20, 41–55 (2002).
White, R., Powell, R., Holland, T. & Worley, B. The effect of TiO2 and Fe2O3 on metapelitic assemblages at greenschist and amphibolite facies conditions: mineral equilibria calculations in the system K2O–FeO–MgO–Al2O3–SiO2–H2O–TiO2–Fe2O3. J. Metamorph. Geol. 18, 497–512 (2000).
Holland, T. & Powell, R. Activity–compositions relations for phases in petrological calculations: an asymetric multicomponent formulation. Contrib. Mineral. Petrol. 145, 492–501 (2003).
Marks, N., Zierenberg, R. A. & Schiffman, P. Strontium and oxygen isotopic profiles through 3 km of hydrothermally altered oceanic crust in the Reykjanes Geothermal System, Iceland. Chem. Geol. 412, 34–47 (2015).
Bédard, J. H. Trace element partitioning in plagioclase feldspar. Geochim. Cosmochim. Acta 70, 3717–3742 (2006).
Xiong, X. et al. Experimental constraints on rutile saturation during partial melting of metabasalt at the amphibolite to eclogite transition, with applications to TTG genesis. Am. Mineral. 94, 1175–1186 (2009).
Collins, G. S., Melosh, H. J. & Ivanov, B. A. Modeling damage and deformation in impact simulations. Meteorit. Planet. Sci. 39, 217–231 (2004).
Wünnemann, K., Collins, G. & Melosh, H. A strain-based porosity model for use in hydrocode simulations of impacts and implications for transient crater growth in porous targets. Icarus 180, 514–527 (2006).
Pierazzo, E. et al. Validation of numerical codes for impact and explosion cratering: impacts on strengthless and metal targets. Meteorit. Planet. Sci. 43, 1917–1938 (2008).
Bottke, W. F. et al. An Archaean heavy bombardment from a destabilized extension of the asteroid belt. Nature 485, 78–81 (2012).
Ivanov, B., Melosh, H. & Pierazzo, E. Basin-forming impacts: reconnaissance modeling. Geol. Soc. Am. Spec. Pap. 465, 29–49 (2010).
Miljković, K. et al. Subsurface morphology and scaling of lunar impact basins. J. Geophys. Res. Planets 121, 1695–1712 (2016).
Pierazzo, E., Artemieva, N. & Ivanov, B. Starting conditions for hydrothermal systems underneath Martian craters: Hydrocode modeling. Geol. Soc. Am. Spec. Pap. 384, 443–457 (2005).
Melosh, H. & Ivanov, B. Impact crater collapse. Annu. Rev. Earth Planet. Sci. 27, 385–415 (1999).
Turtle, E. P., Pierazzo, E. & O’Brien, D. P. Numerical modeling of impact heating and cooling of the Vredefort impact structure. Meteorit. Planet. Sci. 38, 293–303 (2003).
T.E.J. acknowledges financial support from the State Key Lab for Geological Processes and Mineral Resources, China University of Geosciences, Wuhan (Open Fund GPMR210704), and from the Office of Research and Development (ORD) and The Institute of Geoscience Research (TIGeR), Curtin University. K.M. acknowledges Australian Research Council (ARC) funding and the developers of the iSALE hydrocode. H.S. publishes with the permission of the Executive Director, Geoscience and Resource Strategy. P.A.B. acknowledges support from ARC DP170102529.
The authors declare no competing interests.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Figures (1 and 2) and Tables (1–4).
About this article
Cite this article
Johnson, T.E., Gardiner, N.J., Miljković, K. et al. An impact melt origin for Earth’s oldest known evolved rocks. Nature Geosci 11, 795–799 (2018). https://doi.org/10.1038/s41561-018-0206-5
Earth-Science Reviews (2020)
Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland
Chemical Geology (2020)
Annual Review of Earth and Planetary Sciences (2020)
Volatiles in lunar felsite clasts: Impact-related delivery of hydrous material to an ancient dry lunar crust
Geochimica et Cosmochimica Acta (2020)
Detrital zircon evidence for change in geodynamic regime of continental crust formation 3.7–3.6 billion years ago
Earth and Planetary Science Letters (2020)