Allyn River Member

The Allyn River Member is a geologic formation in the New England Orogen in eastern Australia.

Seen in the Hunter River region near Dungog, this stratum is up to 1,000 metres thick, though 740 metres thick at its type locality. Formed in the Visean between 346.7 and 330.9 Ma., it is part of the Flagstaff Formation of sedimentary rocks.

This formation includes green to brown, medium thickly bedded lithic sandstone with turbiditic sedimentary structures and interbeds of brown thinly bedded mudstone.