Here's why:

* Barkly Tableland: This landform is a vast plateau in northern Australia, characterized by its flat, elevated surface. It's a prominent feature of the landscape, with elevations ranging from around 300 to 500 meters.

* Great Artesian Basin: This is a vast underground aquifer, not a landform visible on the surface. It's a significant source of water, but it doesn't have the same physical characteristics as a plateau.

Let me know if you'd like more information on either landform!