The Eramosa Member is a Silurian stratigraphic unit of the Lockport Formation exposed along the Niagara Escarpment in Ontario and western New York State.

No detailed description of the type section has ever been published, and the status of the unit has been subject to many different interpretations.

In a "reference section" in the Niagara River Gorge, the Eramosa was divided into six "units" recognized throughout the Niagara region, but a shaley lower unit previously named for the Hamilton area (the Vinemount Member) was transferred to the Goat Island Formation.

Probably the Eramosa was deposited in several related environments, most likely including shallow, restricted (and poorly oxygenated) marine waters.

The exceptionally preserved biota are present in a stratum of rock about 8 m thick, which extends for around 16 km (9.9 mi) in the South Bruce Peninsula, Ontario.