The Elisabeth Bay Formation, alternatively spelled as Elizabeth Bay Formation, is an Early Miocene geologic formation in the Sperrgebiet, ǁKaras Region of southwestern Namibia, overlying the Blaubok Conglomerate. The freshwater green and red siltstones, sandstones, intercalations of conglomerates and claystones of the formation were deposited in a fluvial environment, infilling a paleovalley incised during the Oligocene low sea stand, which backfilled during the Burdigalian marine transgression. The Elisabeth Bay Formation provides many fossil mammals, snakes and other reptiles.