Chicxulub Impact Crater Microbiome

There is considerable interest in the deep biosphere which influences global biogeochemical cycles. In this work, we present data from the IODP-ICDP Expedition 364, which drilled into the peak ring of the Chicxulub crater, Mexico, responsible for the end-Cretaceous extinction, allowing us to investigate the microbial communities within this structure. Enhanced cell biomass was found in the high-porosity impact suevite, which was deposited within the first few hours of the Cenozoic, demonstrating that the impact produced a new lithological horizon that caused a long-term improvement in deep subsurface colonization. We observed enhanced cell abundances at impact-induced geological interfaces, that can be attributed to the nutritionally diverse substrates and/or elevated fluid flow. Molecular analysis revealed taxonomically distinct microbial communities in each crater lithology dominantly influenced by their porosity. Our work shows that the impact caused geological deformation that continues to shape the deep subsurface biosphere at Chicxulub in the present-day. This work is a significant contribution to our understanding of how the deep biosphere is influenced by events in deep time.