The “Mer des Faluns” sea covered a region between the Cotentin and the Val de Loire during three transgressive episods dated from the Miocene, more precisely between 23 and 15 Ma.

The maximal extension of the Shell-marls of the Mer des Faluns at Miocene (from Dollfus and Lecointre)

The Touraine shell-marls are related to the first transgression, and are characterized by limestone and sandstone matrix shell-marls, deposited under a 0 to 50 m deep sea. They contain lots of bryozoaires, corals, shellfishes (including crabs), sea urchins (scutels) and various bivalves :

Bryozoaires and corals

Bivalves and crab’s pincer

But those series are more famous for their shark and crocodile teeths, and osseous remains :

Shark teeth (0.8 to 3 cm)

Shark teeth in shell-marls

Crocodilian tooth (1,2 cm)

Piece of a ray tooth (1 cm)

Fish palatine teeth (2 and 4 mm)

Finally, some terrestrial mammals remains (mainly teeth) can be encountered in estuary zones.