Archean Drilling Projects
There are several scientific drilling programs that have been carried out in Archean terrains in the past decade and others that are planned in the near future. The aim of most of these drilling projects is to recover relatively well-preserved rock samples from below the present weathering profile and to obtain continuous rock cores that retain soft or friable units that outcrop poorly at the surface. Astrobiology-related studies such as search of pristine morphological or chemical traces of early life form an important part of these projects.
To date, both volcanic and sedimentary sequences have been targeted, and the recovered cores have been analyzed to investigate conditions at the surface of the Archean Earth – the composition, temperature, and redox state of the Archean ocean and atmosphere and the volcanic and sedimentary processes that operated early in Earth history – and, above all, to search for evidence of primitive life. The focus has been the Pilbara...