Ocean of Ooze

The Ocean of Ooze was a body of liquid on Skaro that separated the continents of Davius, the original home of the Thals, and Dalazar, the original home of the humanoid Daleks. (TV21: Genesis of Evil) The Ocean also contained the mist-shrouded, unexplored Forbidden Islands and the Island of Moving Mountains, which constantly changed shape. (DAN:The Dalek Book)

The existence of Davius, Dalazar and the Ocean of Ooze seem to be contradicted by DW: The Daleks and Genesis of the Daleks, in which Thals, Kaleds and Daleks inhabited the same continent.