1. Advanced Centre for Queensland University Research Excellence (ACQUIRE), The University of Queensland, St Lucia, Queensland 4072, Australia
2. Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK

Correspondence to: Ronny Schoenberg¹ Correspondence and requests for materials should be addressed to R.S. (e-mail: Email: ronny@earth.uq.edu.au).

Abstract

The 'Late Heavy Bombardment' was a phase in the impact history of the Moon that occurred 3.8–4.0 Gyr ago, when the lunar basins with known dates were formed^{1, 2}. But no record of this event has yet been reported from the few surviving rocks of this age on the Earth. Here we report tungsten isotope anomalies, based on the ¹⁸²Hf–¹⁸²W system (half-life of 9 Myr), in metamorphosed sedimentary rocks from the 3.7–3.8-Gyr-old Isua greenstone belt of West Greenland and closely related rocks from northern Labrador, Canada. As it is difficult to conceive of a mechanism by which tungsten isotope heterogeneities could have been preserved in the Earth's dynamic crust–mantle environment from a time when short-lived ¹⁸²Hf was still present, we conclude that the metamorphosed sediments contain a component derived from meteorites.