Peering into the Cradle of Life: Drilling the Barberton Greenstone Belt

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In August 2009, the ICDP approved a project to drill the Barberton Greenstone Belt in South Africa. The Barberton is one of the only two places where sedimentary and volcanic rocks are sufficiently well preserved that they retain a reliable record of the conditions on the young Earth, hosting some of the best-preserved successions of mid-Archean (3.5-3.2 Ga) supracrustal rocks in the world. The drilling project deals with what is one of the most intriguing questions in the Earth and biological sciences - where and when did life begin? The sedimentary rocks at Barberton provide a 320 m.y. record of conditions on the land surface and on the floor of earth's ancient oceans. The volcanic rocks have information about the hotter and more dynamic Archean mantle and the setting in which the lavas erupted, giving us an idea of the setting for early life. The surface rocks have been well studied, but the key next step is to obtain fresh enough material to investigate in greater depth the geochemical and biochemical signatures of life using modern analytical techniques. This can only be done by drilling. In addition, the material offers an important opportunity to determine what habitat and energy sources Archean rocks provide to life today and how the characteristics of subsurface habitats alter over billion year time scales. This can only be done by robust microbiological contamination control. The PI led the geomicrobiological study of the ICDP Chesapeake Bay Impact Crater, the first ICDP project to include microbiology. One objective is to apply this expertise to the Barberton project. The project is supported by scientists from 13 countries in five continents and by the mineral exploration industry. In this project proposal we seek to gain support from NERC for a contribution to drilling to secure the UK's involvement in the project. Research groups that will benefit from access to the core material are at the University of Cambridge, Royal Holloway, London, the University of Bristol and the Open University.