a smaller usage of oceania as a continent includes only australia, tasmania, new guinea, and the islands between them. this part of the world is usually called australasia instead. for these reasons, it is "not" correct to say that australasia is part of oceania, because what is meant by 'oceania' is not clear. australasia has an exact definition in biogeography and geology; australasia includes new zealand, australia (including tasmania), and melanesia, new guinea, and the islands just north and east of australia. all these are south-east of the bali–lombok line, also known as the wallace line.