The Sillakkudi Formation is a Late Cretaceous (Campanian) geological formation located in Tamil Nadu, India it forms part of the Ariyalur Group. It dates to the Campanian of the Late Cretaceous.

Description The formation was deposited in a Shallow Marine setting as it shows signs of a mobile deposition of substrate. The diversity of the Mollusc fauna of the formation also indicates a shallow marine deposition.

Fossil content Lamellibranchs and echinoid fragments have been reported from the Sillakkudi formation.

Molluscs from the Sillakkurdi formation Genus Species Material Notes MemberInoceramusI. sp.Karapadites K. karapadense Foraminiferas from the Sillakkudi formation Genus Species Material Notes MemberGlobotruncanaG. arcaG. ventricosaG. elevata

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