PhD: The Geochemistry of Chert Fossils in Deep Time

Chert is a key lithology for the preservation of Precambrian life. These rocks, which are composed primarily of microcrystalline silica, host a myriad of important remains of early life. The lithology is so important due to the high fidelity preservation of fossils and the chemical traces of life that result from its fine grain size and high resistance to weathering and metamorphic alteration. This is coupled with modes of formation that are often found in near surface environments. Cherts host key fossil deposits including: the earliest putative morphological fossils from the Apex Chert (3.46 Ga), Strelley Pool Formation (3.4 Ga), and Farrel Quartzite (3.0 Ga) of the Pilbara craton, Australia; the renowned Gunflint Chert, Ontario (1.88 Ga) which has been suggested as a benchmark for the preservation of early ecosystems; the Bitter Springs Formation, Australia (850 Ma) home to a diverse assemblage of Proterozoic fossils; and the Devonian Rhynie chert, Scotland (400 Ma) which yields key insights into the interactions of early life on land. It is a key rock type for understanding the first three billion years of evolution, but highly variable, as it may result from the silicification of diverse protoliths. This project uses an array of techniques to characterise the petrology of chert and the taphonomy of the associated fossils, to better understand life on Earth in deep time. This project forms part of a thriving cross-disciplinary research area at the University of Manchester. A large group of academic staff and associated researchers are addressing evolutionary and palaeobiology questions through studying ancient life, supported by Manchester’s Interdisciplinary Centre for Ancient Life (http://www.ical.manchester.ac.uk/) and the Computational Biology group in the Evolution, Systems and Genomics Domain (https://www.bmh.manchester.ac.uk/research/domains/evolution-systems-geno...).