Protection of dinosaur footprints in carbonate deposits: the case of Sezze (Latium, central Italy) ichnosite

More than 200 dinosaur footprints were found on three stratigraphic surfaces in the abandoned quarry “Cava Petrianni”, about 70 km south of Rome, nearby the town of Sezze (Latium, central Italy). The ichnosite is located in the westernmost sector of the Lepini Mts., with an exposed carbonate succession belonging to the Lepini-Ausoni-Aurunci Unit. Three distinct trampled surfaces were recognised in a 250-m-thick succession referred to the “Laziale-Abruzzese-Campano domain” deposited in a persistent shallow carbonate platform setting from the Late Triassic to the Late Cretaceous. The footprints, preserved on carbonate platform limestones, are exposed to natural environment degradation (especially karst processes), that can irreversibly modify track morphology, resulting in the loss of details in a site of unique paleontological and paleobiogeographic value (Antonelli et al., 2023). The aim of the present project is to find an appropriate solution in the long-term preservation of dinosaur footprints produced in carbonate deposits from the environmental degradation naturally occurring in paleoichnological and geological sites. The final purpose is both enhancing this palaeontological heritage and proposing a possible solution applicable to other ichnosites with similar conditions. Several consolidants have been tested on the trampled surfaces to evaluate the better in terms of application, costs and results. In particular, a mineral consolidant based on the sol-gel technology (SIOX-5 RE50), a nano-sized silicon dioxide fixative/consolidant in colloidal aqueous dispersion (Nano ESTEL) and TEOS with chitosan were applied. In addition, a bioconsolidation process was tested, applying several bacterial strains, taking advantage from the natural bacterial ability to induce carbonate precipitation (Nigro et al., 2022). Antonelli M., Romano M., De Sario F., Pignatti J., Sacco E. & Petti F.M. (2023) - Inferred oviraptorosaur footprints in the Apenninic Carbonate Platform: New tools for the identification of trackmakers from the Sezze ichnosite (lower-middle Cenomanian; central Italy). Cretaceous Res., 141, 105362. https://doi.org/10.1016/j.cretres.2022.105362. Nigro L., Mura F., Toti M.P., Cirigliano A. & Rinaldi T. (2022) - Carbonatogenic bacteria on the ‘Motya Charioteer’ sculpture. J. Cult. Herit., 57, 256-264. https://doi.org/10.1016/j.culher.2022.09.009.