Tracing the Origins of Life in Earth's Oldest Sedimentary Rocks

(C. P. Marshall)

Examining remnants of organic material in Earth’s oldest sedimentary rocks is an essential part of tracing the origins of life on our plant and important for developing techniques to search for traces of life on other plants. Accordingly, carbonaceous materials in Early Archaean (3.2-3.5 billion year old) sedimentary rocks are coming under scrutiny to determine whether evidence of biology can be elucidated. The Archaean Pilbara Craton, Australia, is the best place in the world to study the early Earth – it has a geological history from >3.5 through to 2.4 billion years old, preserved at low metamorphic grade with low strain rocks that contain Earth’s oldest hydrothermal systems. The aim of this project is to elucidate the macromolecular structure of the carbonaceous materials in these rocks and hence determine any molecular biomarkers which may provide evidence for either a biologic or and non-biologic origin of these materials.