Ministère de la Culture et de la Communication
Université Versailles Saint-Quentin


Accueil > News

Yttrium traces out chemical ghosts in fossils

par Bénédicte Charbonnel - publié le , mis à jour le

In fossils, the "devil" is also in the details, such as "chemical ghosts" invisible to the paleontologist eyes but revealed using cutting-edge imaging methods. Among the latter, trace elemental 2D mapping using the highly intense X-ray beams available at synchrotrons recently revealed a series of such previously unseen details of flattened fossils, providing critical new information about their biology, environment and/or preservation. Using this method, palaeontologists usually target elements up to the strontium, particularly interesting in vertebrates as it incorporates into bone. In addition to these elements, researchers from IPANEMA, SOLEIL synchrotron and the Muséum national d’Histoire naturelle also mapped yttrium (the element that follows strontium) in two fossil fishes and a squid, from different ages and depositional environments. While strontium similarly substitutes for calcium in calcium phosphates (incl. apatite, the main component of bone) and in calcium carbonates (the main component of limestone and shells) resulting in the absence of chemical contrast in the case of fossils preserved in limestone, yttrium preferentially substitutes for calcium in calcium phosphates, offering anatomical contrasts for a wider range of fossils. Published on June 12, 2018 in the journal Palaeontology, this method should also allow to pinpoint calcium phosphates in fossils and other geological materials, as well as, thanks to the high sensibility (up to the µg/g range) offered by synchrotrons, to identify traces of bone in the fossil record, particularly in early fossil vertebrates.

Contact researcher

Pierre Gueriau |

Voir en ligne : Show me your yttrium, and I will tell you who you are : implications for fossil imaging, Pierre Gueriau, Clément Jauvion et Cristian Mocuta. DOI : 10.1111/pala.12377