Abstract
Two recent papers [1, 2] report geological, geochemical, and geochronological data from the early Archaean of West Greenland to suggest that life existed on Earth by ≥3850 Myr ago. The crucial evidence is based on zircon U-Pb age measurements of magmatic rocks (metamorphosed to orthogneisses) regarded to be younger than adjacent metasedimentary rocks containing components with a carbon isotope signature characteristic of a biological origin [1]. This new lower age limit for the existence of life on Earth overlaps the period at which massive, destructive impacts were occurring on the moon’s surface (and presumably on Earth as well), probably terminating close to 3.8 Gyr ago [3].
A critical re-examination and re-interpretation of the relevant geochronological evidence in West Greenland suggests that the rocks of possibly biological significance are some 120–190 Myr younger than claimed in the cited papers. By this time, major cataclysmic impacts would long have been over, and more congenial conditions for earliest life established.
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Mojzsis, S.J., Arrhenius, G., McKeegan, K.D., Harrison, T.M., Nutman, A.P. and Friend, C.R.L.: Evidence for life on Earth before 3800 million years ago. Nature, 384 (1996) 55–59.
Nutman, A.P., Mojzsis, S.J. and Friend, C.R.L.: Recognition of ≥3850 Ma water-lain sediments in West Greenland and their significance for the early Archaean Earth. Geochim. Cosmochim. Acta, 61 (1997) 2475–2484.
Wilhelms, D.E.: The geologic history of the Moon. U.S. Geol. Surv. Prof. Paper, 1348 (1987) 127p.
McGregor, V.R. and Mason, B.: Petrogenesis and geochemistry of metabasaltic and metasedimentary enclaves in the Amîtoq gneisses, West Greenland. Amer. Mineral., 62 (1977) 887–904.
Bennett, V.C., Nutman, A.P. and McCulloch, M.T.: Nd isotopic evidence for transient, highly depleted mantle reservoirs in the early history of the Earth. Earth Planet. Sci. Lett., 119 (1993) 299–317.
Schiøtte, L. and Compston, W.: U-Pb age pattern for single zircon from the early Archaean Akilia association south of Ameralik fjord, southern West Greenland. Chemical Geology, 80 (1990) 147–157.
Moorbath, S., Whitehouse, M.J. and Kamber, B.S.: Extreme Nd-isotope heterogeneity in the early Archaean — fact or fiction? Case histories from northern Canada and West Greenland. Chem. Geol., 135 (1997) 213–231
Moorbath, S. and Whitehouse, M.J.: Age of the Isua supracrastal sequence of West Greenland: a plausible repository for early life, In: J. Chela-Flores and F. Raulin (ed.), Chemical Evolution: Physics of the Origin and Evolution of Life. Kluwer Academic Publishers, Dordrecht, 1996, pp. 87–95.
Hamilton, P.J., O’Nions, R.K., Bridgwater, D. and Nutman, A.: Sm-Nd studies of Archaean metasediments and metavolcanics from West Greenland and their implications for the Earth’s early history. Earth Planet. Sci. Lett., 62 (1983) 263–272.
Moorbath, S., Taylor, P.N. and Jones, N.W.: Dating the oldest terrestrial rocks — fact and fiction. Chem. Geol., 57 (1986) 63–86.
Jacobsen, S.B. and Dymek, R.F.: Nd and Sr isotope systematics of clastic metasediments from Isua, West Greenland: identification of pre-3.8 Ga differentiated crustal components. J. Geophys. Res., 93 (1988) 338–354.
Nutman, A.P., McGregor, V.R., Friend, C.R.L., Bennett, V.C. and Kinny, P.D.: The Itsaq Gneiss Complex of southern West Greenland; the world’s most extensive record of early crustal evolution (3,900–3,600 Ma). Precamb. Res., 78 (1996) 1–39.
Mezger, K. and Krogstad, E.J.: Interpretation of discordant U-Pb zircon ages: An evaluation. J. Metamorphic Geol, 15 (1997) 127–140.
Maher, K.A. and Stevenson, D.J.: Impact frustration of the origin of life. Nature, 331 (1988) 612–614.
Sleep, N.H., Zahnle, K.J., Kasting, J.F. and Morowitz, H.J.: Annihilation of ecosystems by large asteroid impacts on the early Earth. Nature, 342 (1989) 139–142.
Appel, P.W.U., Fedo, C.M., Moorbath, S. and Myers, J.S.: Well-preserved volcanic and sedimentary features from a low-strain domain in the ∼3.7–3.8 Ga Isua greenstone belt, West Greenland. Geology, (submitted for publication).
Dickin, A.P.: Radiogenic Isotope Geology, Cambridge University Press, Cambridge, 1995.
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Moorbath, S., Kamber, B.S. (1998). Re-Appraisal of the Age of the Oldest Water-Lain Sediments, West Greenland. In: Chela-Flores, J., Raulin, F. (eds) Exobiology: Matter, Energy, and Information in the Origin and Evolution of Life in the Universe. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5056-9_7
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DOI: https://doi.org/10.1007/978-94-011-5056-9_7
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