0000000000364254
AUTHOR
C. Thomazo
showing 4 related works from this author
Tracking microbial signatures in stromatolites at micrometer scale with in situ iron isotopes. M-fed (Microbialites: formation, evolution, diagenesis)
2019
International audience
Iron isotopes in micropyrites from the 2.7Ga Tumbiana Formation (Western Australia)
2019
International audience; Stromatolites are considered to be the major drivers for the oceanic oxygenation during Archean time. However, respective rolesof photosynthetic and chemolithotroph organisms in these Archean rocks is not precisely demonstrated. Primarysub-micrometer pyrites associated with pristine organic matter are widespreadin Archean and modern sediments. Iron isotopes are fractionated by redox processesand biological activitiesand are widely used for tracing paleoredox conditions, diagenetic processes ormetabolic signaturesas iron respiration (DIR). Sub micrometer δ56Fevalues ofmicropyritesassociated with organic matter-laminae and CaCO3-SiO2matrixin stromatolites from the 2.7G…
Early Triassic proliferation of microbial deposit
2019
International audience; In modern examples of well-developed microbial-dominated deposits associated with metazoan organisms can be currently found in various environments including but not restricted to lagoons in Polynesia (Sprachta et al., 2001), the warm water of the Cuba (e.g., Bouton et al., 2016; Pace et al., 2018), the hypersaline lakes of the Great Salt Lake (USA; e.g., Bouton et al., 2016; Vennin et al., 2019; Vanden Berg, 2019), or the alkaline Satonda Crater Lake in Indonesia (Arp et al., 2003; Satuyana et al., 2010). In Early Triassic, several authors indicated that microbial deposits are frequently associated with sponges, bivalves, brachiopods, ostracods and echinoderms and d…
Molecular preservation of organic microfossils in Paleoarchean cherts
2019
International audience; Fossilization processesandthe increase of temperature and pressure conditions associated withburialinevitably alter the original biochemical signatures of organic molecules.At a certain stage, biogenic and abiotic organic structures may become undistinguishable [1].Cherts (i.e.silica-rich rocks)are well known forthe morphologicalpreservationof fossilized microorganisms.Recently,spatially resolvedinvestigations usingsynchrotron-based XANESmicrospectroscopyrevealedthatmolecular information about the organic precursor of3.4 Gamicrofossils, was preservedintheStrelley Pool chert(Pilbara, Western Australia),despite a metamorphichistory so far believed to be incompatible wi…