Impressive concentrations of fossilized bivalves (mollusks with shells) can be found in parts of the coast of the island of Chryssi or Chrissi Island (Gaidouronisi) and mainly at the eastern end of the bay of Belegrina.
Wherever you step, you will see fossilized bivalves, which together with sediments form small solid rocks.
These concentrations, as explained to us by the geologist of the Natural History Museum, Charalambos Fasoulas, are called thanatocenosis.
According to him, for some reason, numerous bivalves that lived there died suddenly. Their shells gathered in piles and over time became fossilized.
We do not know exactly the reason for the death of these bivalves, but it may be due to changes in salinity or water temperature.
Glacial and interglacial periods recorded over the millennia obviously played their role.
However, if these fossils are categorized as Pleistocene, then the geological period they cover takes us back from 2,000,000 to 11,700 years.
49 different types of fossils have been identified on the island, including bivalves, several gastropods, i.e. shells and clams, scaphopods, corals and sea urchins.
Fossils can be seen north, northeast, south and southeast of Chryssi, but the most impressive concentrations are in Belegrina