Buildings that 'Speak': Ichnological Geoheritage in 1930s Buildings in Piazza della Vittoria (Genova, Italy)

The geoheritage value of sedimentary building stones has mainly focused on physical sedimentary structures and body fossils. By contrast, little attention has been placed on the geoheritage significance of ichnofabrics, which are the sedimentary fabrics that have been reworked by organisms. This study aims to fill this gap by analysing the ichnofabric found on the buildings of Piazza della Vittoria, in Genova (Italy). Here, unusually visible and well-preserved specimens of the fossil burrow Bichordites are observed on the historical buildings designed by Marcello Piacentini, one of the local most prominent architects of the 1930s. The Bichordites of Piazza della Vittoria are winding meniscate burrows with a central string-like structure. Here, we interpret this ichnofabric as the result of the activity of a community of echinoids bioturbating a sand wave system. We have also located the historical quarry that provided material for the studied buildings with the same ichnofossils exposed. Surprisingly, the cuts on display on the buildings are much nicer than those in the outcrops and more taxon specific characteristics can be observed just on the tiles rather than in the field. For all these reasons, the geoheritage value of the Piazza della Vittoria ichnofabric relies in its unique scientific significance, the cultural value, and its potential future applications in research, teaching, urban geotourism and reference site.